Friday, December 13, 2024
Facebook Linkedin RSS Twitter
Home February 2019

February 2019

Protecting Wind-Turbine Bearings

Dayananda Raju
-
0
Protecting Wind-Turbine Bearings

While wind-turbine functionality relies upon fully operational rolling bearings, these precision components typically will be buffeted by a wide variety of adverse — sometimes extreme — operating conditions and environments. As a result, damage modes can develop, potentially jeopardizing bearing performance and service life and, in turn, a turbine’s reliability and productivity.

Fully understanding common failure modes in turbine bearings can be a challenge, especially since every premature bearing failure will be unique due to the many possible causes in the context of particular operating conditions. Despite the challenges, there are ways to reduce the likelihood of premature bearing failures, minimize maintenance and operating costs, promote extended bearing service life, and, ultimately, help keep turbines up-and-running as intended.

The role of condition monitoring is expanding with a capability to detect a turbine’s power output. (Courtesy: SKF USA Inc.)

Bearing types and applications

In general, bearings in rotating equipment serve to support shaft loads, reduce friction with rolling elements, and provide shaft location and system flexibility/rigidity. For wind turbines, distinctly designed bearing types have been engineered to meet application demands. Among the types:

Spherical roller bearings: Typically have two rows of rollers running in two raceways. This design enables them to withstand high radial and axial loads and reduce friction and heat, while being forgiving to misalignment and flexible system conditions. They are most commonly used to support the main shaft of a wind turbine.

Cylindrical roller bearings: Are most commonly used in gearboxes and generators. They can also be used as main shaft bearings. Their design can range from single roller row versions (which can withstand slightly lower radial loads at higher speeds) to designs with up to four roller rows (supporting very high radial loads at moderate speeds).

Tapered roller bearings: Incorporate conically shaped rollers in up to four rows and tapered inner and outer raceways. The intricate design typically suits positions requiring rigidity and high running accuracy, while reducing vibration. Due to their durability, these bearings will be used in a turbine’s main shaft and in gearbox applications where high thrust load to radial load ratios exist and high system rigidity is required.

Deep groove ball bearings: Facilitate radial and axial loads in both directions. A deeper groove enables them to deal with higher speeds ideally suiting electric motors and generators in turbines.

Slewing bearings: (with large standard diameters of 3 to 6 meters and gear teeth on inner/outer rings) Feature multiple rows of balls/rollers and are especially robust to withstand slow-speed/oscillating conditions and harsh weather conditions. These types of bearings allow for the turbine blades to pitch back-and-forth at a controlled pace for controlled energy output. In addition, this type of bearing will be used in yaw position to control a nacelle’s direction during operation.

Signs of failure

The reliability of equipment always stands tall as a central challenge for wind-farm operators, and the reliability of bearings at all points in a wind turbine is a critical part of the mix. Failure modes can occur — due to various root causes — and threaten bearing performance and reliability at every turn. Among the most commonly encountered failure modes:

Cracks with white etching (often called WECs, or white etching cracks) can develop in bearings at multiple wind turbine gearbox locations — especially prevalent in larger megawatt and multi-megawatt class wind turbines. Such cracks (occurring at the end of the failure chain) develop within the microstructure of bearing steel and appear white when acid-etched. This can be detected microscopically on a bearing’s subsurface.

Their origin, based on bearing failure analyses, often can be traced to a bearing’s rolling contact fatigue and to physical parameters that can accelerate rolling contact fatigue. The fatigue may be caused by higher stresses than anticipated (driven by heavy moment loads, friction and heat, and/or misalignment and other physical factors) or by diminished material strength (due to environmental factors, including water contamination, corrosion, and/or stray electrical currents).

Pre-emptive recommendations: Bearings manufactured from premium steel and with compressive residual stresses induced by previous loading can help counteract the imposed higher stresses contributing to fatigue. Protections to reinforce the strength of a bearing’s material, depending on the conditions, include specialized protective surface treatments and coatings, hybrid bearings integrating extremely hard and durable ceramic rolling elements, and high-strength stainless steel for corrosion resistance.

Adhesive wear (also known as smearing or scuffing) occurs when two inadequately lubricated surfaces slide against each other, causing material to be transferred from one surface to the other. In addition, the resulting friction can heat the material to temperatures that cause re-hardening. Both these effects alter the microstructure of a bearing’s rollers and raceways, creating increased stress, excess friction, and unwanted heat leading to degeneration. Over time, these factors will wear a bearing to a point where it is no longer functional.

Pre-emptive recommendations: A specialty black oxidation treatment applied (by the bearing manufacturer) to a bearing’s inner and outer rings and rolling elements can provide resilience and protection against adhesive wear (as well as for several other failure modes). Bearings with such surface treatments can be deployed as replacements and upgrades in existing turbine installations, since dimensions will be unchanged from originally installed bearings.

Micropitting (or surface distress) presents as incredibly small cracks that gradually increase in size and interrupt the smooth running of a bearing. This degradation is usually caused by inadequate lubrication and commonly occurs in main shaft bearings and wind-turbine gearboxes — affecting not only the bearings, but also the gear teeth. The resulting damages impair a bearing’s function and cause concentrated stresses and high frictional heat. Once initiated, the damage progresses very quickly, leading to loss of bearing function, spalling (the flaking of bearing material), and failure.

Spherical roller bearings commonly used in a turbine’s main shaft can withstand high radial and axial loads while reducing friction and heat. (Courtesy: SKF USA Inc.)

Pre-emptive recommendations: Proper lubrication management and daily practices can help prevent these conditions. Maintenance staff should guard against over-greasing or under-greasing, using the wrong lubricant, and/or mixing incompatible lubricants, while properly lubricating when the time is right and keeping watch for deteriorating grease or oil, water contamination, and particulate contamination. Proper sealing design to maintain appropriate levels of lubricant availability goes a long way in mitigating lubrication starvation.

Moisture corrosion forms when water or corrosive agents reach the inside of a bearing. When lubricant is not providing sufficient protection for a bearing’s steel surface, rust can begin to develop, damaging the bearing. Free water presents a high risk to a bearing and it takes only a small amount of water to significantly shorten service life.

Pre-emptive recommendations: Corrosion can be avoided by correctly sealing the areas where bearings are located. Implementing a humidity control system and proper component design against occurrence of condensation within a system may be appropriate as proactive options.

Emerging trends

Several encouraging trends demonstrate that progress is being made toward helping wind-farm operators reduce maintenance costs and extend the lifecycle of components, including bearings.

Improved testing: While components in turbines undergo thorough testing before being placed into operation, parts historically have been evaluated individually instead of how they will work together with other components in a system. This approach is changing with more detailed testing involving all interacting components and the use of advanced simulation of conditions to mirror real-world turbine applications.

Automatic lubricant delivery systems: One of the most important steps on the road toward proper lubrication is deciding how to deliver lubricant effectively to all the lubrication points in a nacelle. Traditional manual-lubrication tools have been augmented with automatic lubrication systems for various locations in a wind turbine. These single-point or centralized multi-line lubrication systems have been engineered to dispense exact and clean quantities of the appropriate amount of lubricant where and when required — lifting a heavy burden from the shoulders of maintenance staff.

A combination of bearing arrangements on a turbine’s main shaft can improve reliability. (Courtesy: SKF USA Inc.)

Extended roles for condition monitoring: Condition monitoring technologies have increasingly served to enable early detection of operating abnormalities in rotating equipment, including wind turbines. Abnormalities are identified based on measurements of various physical operating parameters, including vibration, temperature, displacements, and others. The measurements make it possible to pinpoint problems with bearings and other components before they can escalate to failure and to make pre-emptive remedial fixes.

The role of condition monitoring is expanding with a capability to detect a turbine’s power output, which may be placing components under too much strain. By monitoring power output, operators can adjust the power output as necessary to potentially extend the operational life of main shaft and gearbox bearings by up to five years.

Turbine failure is not an option for wind-farm operators, and a first line of defense is to protect bearings against common failure modes and, in the process, minimize operation and maintenance costs. Partnering with a knowledgeable bearings specialist can help in implementing the best practices to sustain any installation.

Maintaining a maintenance plan

michele-admin
-
0
Maintaining a maintenance plan

Even though predictive maintenance has proven its ability to avoid unscheduled stoppages and faults in critical components, there are still many companies that fail to consider new monitoring technologies in their maintenance plans and strategies. Often, predictive maintenance is considered as a cost and not as an investment with return, which is far from the experience of any industry that has opted for this technique and is seeing the investment quickly repaid.

In the case of wind-energy generation, where the already high costs to repair faults in the critical machinery in wind turbines combine with the logistical costs required to be able to perform the repairs, the absence of a predictive maintenance system featuring various additional technologies entails a succession of substantial costs.

Faults that can be repaired where the wind turbine is located are generally linked to the bearings and the shaft. (Courtesy: Shutterstock)

As an example, below are a series of average costs that can affect any wind farm that does not use an adequate maintenance strategy. A study by Atten2, a Spanish company specializing in the development of on-line optical sensors for the monitoring of lubricating oils, shows the investment in predictive maintenance technologies represents a strategic investment with a high ROI. The data has been taken from a study analyzing incidences registered in a year at a wind farm with 44 wind turbines.

Down-tower repairs

Down-tower repairs result from a serious fault that cannot be resolved in-situ and, therefore, involve dismantling the wind turbine and lowering it to the ground. The expenses from this type of fault start in the logistics: Renting the crane needed for this operation represents an estimated cost of 15,000 euros.

In the case of this wind farm, with 44 turbines, the historical rate of faults related to the gearbox that involved dismantling the wind turbine represents 6.41 percent of the total number of incidences registered each year. The figure in this particular case is in line with the overall percentages in the sector, where the average rate for this type of fault is 6.5 percent.

The consequences of these faults, which could be minimized by implementing a complete condition monitoring system, are classified in the wind farm under study as minor, severe, and irreparable.

On average, minor faults require an average investment of 30,000 euros per repair, an amount that rises to 45,000 euros in severe incidences and that reaches 77,000 euros for faults that cannot be repaired, for cases where the gearbox has to be replaced. In the specific case of the wind farm under study, the costs associated with the types of faults are 17,400, 59,400, and 70,480 euros respectively, which pushes up costs to 147,600 euros per year. This figure is in addition to the cost of renting the crane as previously mentioned.

A study by Atten2, a Spanish company specializing in the development of on-line optical sensors for the monitoring of lubricating oils, shows the investment in predictive maintenance technologies represents a strategic investment with a high ROI. (Courtesy: Atten2)

Up-tower repairs

These are repairs that can be carried out in the same location as the gearbox, without having to dismantle or lower the machinery. Faults that can be repaired where the wind turbine is located are generally linked to the bearings and the shaft, low risk faults that do not require large investments to fix them.

Additionally, these incidences that can be resolved without dismantling can incur fewer costs as there is no need for the logistics inherent in up-tower repairs. These repairs also occur less often. In the wind farm under study, this type of fault represents 2.3 percent of the total percentage, of which 80 percent is due to the bearings and 20 percent due to the shaft. The investment required for repair is 5,712 euros a year.

This amount may seem modest, especially in comparison with down-tower faults, but in both cases, it should be noted that the estimated lifespan of a wind farm is 20 years, and currently, wind turbines are expected to operate for up to an additional 10 years. Therefore, a precise calculation of the overall costs of not using a correct predictive maintenance strategy yields astronomical figures: 4.6 million euros over the useful life of the 44-turbine wind farm under study.

Keeping an Eye on Bats

Kenneth Carter
-
0
Keeping an Eye on Bats

Whenever big mechanical systems are constructed, there’s always a risk that it might interfere with wildlife. That is often the nature of progress.

Massive wind turbines sometimes conflict with birds, but they also can conflict with bats as well.

A recent study by the Canadian Wind Energy Association, DNV GL and Natural Resource Solutions, Inc. has put together a comprehensive resource with respect to wind energy and bat conservation. The study, Wind Energy and Bat Conservation – A Review by the Canadian Wind Energy Association, took three years to compile and draws upon an expansive treatment of subjects that include the effectiveness of bat-impact avoidance and minimization measures, wind facility siting considerations, post-construction monitoring, emerging technologies, and potential mitigation options.

A hoary bat roosts in a Douglas fir tree. The Wind Energy and Bat Conservation Review contains information on the 20 bat species in Canada and how the wind industry is working to minimize potential impacts to them. (Courtesy: CanWEA)

And although various aspects of a wind farm have the potential to affect bats, the operational phase receives the most attention in the report, according to Dr. Kimberly Peters, senior biologist for environmental and permitting services with DNV GL.

“I think in terms of potential negative effects on bats, operational fatality rates are the main concern, and so even during the siting phase, what developers will be looking for are to make smart siting decisions and to minimize any attractants,” she said. “Bats, for instance, are attracted to water, so the aim is to not create any unnecessary water sources. Also, not to place turbines near structures like hibernacula where bats congregate, but the real potential effects are going to occur during the operational phase — while turbines are actually spinning. That is when we tend to see fatalities, particularly during migrations, so we primarily focused on migratory bats.”

The review also highlights the positive role that the wind industry can play when it comes to bat conservation, and how, through participating in bat research and large-scale bat conservation efforts, for instance, the industry can help sustain bat populations over the long term in Canada. At the same time, wind energy represents a renewable energy source that will ultimately reduce the country’s reliance on fossil fuels and stem expected climate-change impacts to bats, humans, and other wildlife.

Communication tool

The point of the study is to use it as a communication tool between developers, regulators, conservation organizations, and other stakeholders in the public in order to add transparency and come up with the best, science-based solutions, according to Peters.

“For every decision that’s made, the decision makers can say, ‘OK, here was the set of facts we were working from. These are the predictions we made. There’s always going to be uncertainty, but based on those predictions, this is why we made that decision,’” she said. “For anybody who may disagree with a particular approach, the science will be right there for them. They may say, ‘well, we would have made a different decision,’ but at least everybody’s working from the same set of facts. I think one of the most helpful things to come out of this three-year effort was the science-based decision framework that we developed, which can be used by developers, conservationists, and regulators alike.”
Looking at siting issues is important, but Peters added that the science about siting and bats is still limited.

“We tend to recommend that micro-siting decisions be made with bats in mind, but I’m going to caveat that with there’s not a lot of definitive science that shows what kinds of micro-siting decisions have a real effect on what happens during the operational phase,” she said.

General decisions based on what’s known about bat biology can be used, but there are few studies that have actually examined the location of turbines in relation to where bats hibernate and what that specific outcome on bat populations may be, according to Peters.

Accounting for dynamics

But the extensive study takes into account many different dynamics that are happening.
“There are hypotheses that bats may actually be attracted to wind turbines, and so there’s been some concern,” she said. “If they are attracted, are they attracted by the turbine surface itself? Are insects attracted by the lighting, which in turn could attract bats? There’s still a lot of uncertainty there, but what we do know is that many species of bats in North America are experiencing very steep declines, primarily from things like disease and potentially things like pesticides that are taking away their prey base. They have also, as you know, been found as fatalities at wind farms. The industry is really interested in getting a better understanding of where they fall in terms of pressures on the bats and where they can help. That was where we were coming from in initiating this.”

Different species of bats behave differently, and this study has taken various bat species into account as the researchers gathered their data, according to Peters. The study tends to focus on migratory tree bats.

“Those are bats that don’t tend to congregate in big groups in caves, the way most people envision them,” she said. “They tend to breed and roost in treed areas, then they migrate. They’re going from Canada down into their wintering grounds, which are mainly in the U.S. and Mexico. Those are the ones that we find most often when we’re doing fatality searches under turbines, but the good news is those are not the bats that are getting hit really bad by disease. There’s a highly fatal disease known as white-nose syndrome that has really knocked back many of Canada’s and the U.S.’s species of cave-roosting bats. Those are the species that fortunately are not often found as fatalities at wind farms.”

Different frequencies

Another way the experts group bats is by their frequencies, according to Peters.
“Some species of bats are more likely to respond to something like an acoustic deterrent, whereas others that communicate and hunt and navigate at different frequencies may not respond as much,” she said. “I think as we move forward and we’re thinking about different kinds of technology and emerging technologies in particular, we need to understand that some are going to be more effective for one species than another. That’s why it’s really important for developers to understand what the potential bat species at their particular project are going to be, so they can think about adopting the correct kinds of technology or other measures that are going to be more effective.”

The way the industry currently assesses what the effects of a turbine or mitigating technology are is to determine how many bats are killed, according to Peters.

“The main way that you determine what your potential impacts are is by counting dead things, or lack thereof, under turbines,” she said. “That’s the question most want to get to. You can do other kinds of studies to see if there are any behavioral differences or if fewer bats are in the area, but primarily when you’re looking at the project itself, you want to know if you’re causing any bat fatalities and what species they are. There’s a burgeoning science behind the various methodologies for estimating how many bats were actually killed. You have searchers going out once every three days or once every week or month, and they’re obviously not going to find everything. There are different models that will adjust for what are known as detection biases, so you look at things like observer detection rate. How well are they seeing the bats? Are they passing by some that they’re missing?”
In addition, most models take into consideration scavenger removal, according to Peters, which essentially means that some dead bats may end up as dinner before they can be counted.

“It gets really complex because things can change over time, for instance some carcasses become less palatable if they sit out there longer, and so these models are quite sophisticated and take many factors into account,” she said.

Additional search parameters that can vary include the search duration, the size of the area searched, and the difficulty of the terrain around the turbines, according to Peters. Other considerations are carcass distributions around the turbines and where they end up after the initial impact with a turbine.

“All those things are taken into account through modeling, so it’s really quite interesting,” she said. “You can get a better understanding of seasonal differences and spatial differences and all kinds of neat things.”

Wind energy in context

As far as where turbines fall regarding their danger to bats, it is really minimal comparatively for most species, according to Peters.

“We think it’s much lower than several other pressures; I’m an ecologist, and we speak in things in terms of pressures,” she said. “What pressures are these species facing, at a population level? For several species, No. 1, no question, is going to be white-nose syndrome.”

But there is more information coming out in terms of environmental contaminants such as pesticides, according to Peters. Those environmental factors may not affect bats directly, but they could have an indirect impact.

“They certainly affect their prey base,” she said. “There have been some severe drops in flying insect populations, all over the world really, that we’ve seen recently. They’re just sort of disappearing, and the main culprit appears to be pesticides, compounded with things like deforestation and other kinds of human developments that take away their habitats.”

Climate change

Climate change is also likely to have a much bigger impact on bats than turbines ever could, according to Peters.

“There are going to be definite impacts from climate change,” she said. “It’s on target to be one of the main pressures on bats. It’s going to do things like increase the spread of disease. It’s going to heat up their hibernacula. I’ll get technical here for a second: Bats need to hibernate. Several species of bats need to hibernate through the winter, and so they’re all clustered in these caves, and they slow down their systems, so they’re not wasting energy, but if it warms up in those hibernacula, they’ll wake up, and they start burning calories and may starve to death depending on how many times they do wake up.”
And when the bats do emerge from hibernation, they may not have enough food to eat, according to Peters.

“We call it decoupling, which means that when a species like a bat most needs its prey, it’s not available because the triggers on the timing are not lined up anymore,” she said. “Insects tend to emerge based on ambient temperatures, so if insects are emerging too early, they won’t be available when bats most need them, like when they have pups and are nursing; these things take extra energy. Again, that’s going to cause population decline. I would call several things out as more impactful than wind turbines, including disease, contaminants, habitat loss, and climate change. But collisions with wind turbines are also a pressure, and that’s why the industry understood they needed a resource like this document so that they can be playing their part.”

Peters also notes that the industry is also providing an energy source that will reduce the need for burning fossil fuels – the main driver of global climate change.

“It’s a matter of responsibly growing wind capacity while minimizing any potential negative effects,” she said. “On the whole, the positives outweigh the negatives.”

Thermal video cameras and acoustic detectors to record bat activity and behavior are installed at a wind turbine. (Courtesy: CanWEA)

Avoiding turbines

An obvious question many may ask is how a bat could collide with a turbine in the first place since they have echolocation abilities. The short answer is the experts don’t know exactly why bats are active around turbines, according to Peters.

“First of all, it’s important to note that when you see a turbine on the horizon, it looks like it’s moving really slow, but those blades are moving fast, especially at the tips,” she said. “As soon as a bat moves into what we call the rotor swept zone, it’s in danger. They’re not going to be able to detect a blade before they get hit. Unfortunately, they tend to come in, and many sort of hang around the nacelle. They’re in and out and putting themselves in danger multiple times. There are some hypotheses out there that they perceive the towers as a water or foraging source, and they come in, and they’re trying to drink or glean insects off the side of the turbine. That’s why one of the technologies that’s being tested is different kinds of texturized turbine coatings. As you know, bats find their way around and they find drinking and eating opportunities by sonar. The signal that they’re getting back from the turbine monopole may be similar to that of water.”

Some studies with different kinds of texturized coatings have been done by Texas Christian University, according to Peters, but are still in the early stages of development and testing.
“The coatings are designed so that the signal coming back to the bats does not make them think that they’re coming to a water source,” she said. “They actually have video of bats on untreated turbines making contact with the paint, purportedly because they either think it’s water or they think it’s a smooth leaf surface and they’re trying to pull insects off it. When you get into biology and behavior, things get really complex really fast.”

Another area that’s been considered is the lighting on turbines, but it appears that the lights don’t affect bats as much as one might think, according to Peters.

“It would seem to make sense; you would think the lighting attracts insects and then insects attract bats, but it’s mostly red lighting now on top of turbines, and they have not found any relationship between either bat activity or bat fatalities around those lights,” she said. “That’s a good thing.”

Another hypothesis is that bats may be mistaking turbine monopoles for natural structures, according to Peters.

“Bats don’t see very well, but they can see a little bit,” she said. “If they’re looking for trees, which are their habitat, they may misperceive a turbine as a tree because it’s this sort of long tall structure on the horizon. One technology that is being tested by the University of Hawaii and the USGS and others is installing low-level lighting around turbines so that it differentiates it just enough for the bats so that they don’t perceive it as a tree anymore. It may potentially not be as attractive.”

Canada, the U.S., and beyond

Although the study was done for Canada, Peters said much in the document is relevant to the U.S. as well.

“There are things like species maps that are targeted toward Canada, but most of the species we’re talking about, most of the potential effects that we’re talking about, the different kinds of models that are used, those are prevalent in the U.S. as well,” she said. “I think that if we were to create a similar source, a resource for the U.S., there would be changes, and we would focus it more on the regulatory climate, conservation goals, and what regions are going to be expecting different things.”

But Peters said the study also addresses emerging technologies that are being used not just in Canada, but globally.

“A lot of these technologies, things like bat detection systems and automated detection minimization systems or detection deterrent systems, many of these are being developed in the U.S. and Europe but used globally,” she said. “I know that Europe has a lot of concerns about their bats as well, so there’s been research done there, and we’ve incorporated some of that research into the report.”

And that the review has drawn upon so many resources is what makes this study unique, according to Peters.

“There’s so much being done with respect to bats and wind right now, but it’s published all over the place,” she said. “Some of it is published or even unpublished — what we would call the gray literature. What we were able to do is pull pertinent information from all these resources together into one document. We were also able to draw upon DNV GL’s experience. We have over 2,300 renewable energy experts around the world. We have an incredible team of renewables engineers, policy experts, biologists, wind-energy analysts, so we were able to draw upon that. We pulled it all into one place and summarized it in a way that is usable by anyone.”

FOR A COPY OF THE REPORT  tinyurl.com/batsandwind

Tillman introduces glove choices for cold weather

Wind Systems staff
-
0
Tillman introduces glove choices for cold weather

Keep Jack Frost from nipping at your fingers with the Tillman 1772 and 1773 high-visibility cold weather gloves. Both the 1772 and 1773 feature a 13-gauge polyester with ANSI A2 Cut Resistance with a choice of either a sandy nitrile grip (1772) or a sandy latex grip (1773).

Tillman’s 1772 and 1773 offer three levels of protection for your hands:
• Keeping hands safe with an ANSI A2 Cut Resistance.
• Keeping hands dry with either a 3/4 dip nitrile coating, 1772, or a full dip latex coating, 1773.
• Keeping hands warm with a soft acrylic terry for warmth that won’t chafe the user’s hands or wrists for all-day comfort.

The Tillman 1772 and 1773 cold weather gloves. (Courtesy: Tillman)

About the 1772
• High-Vis 13-gauge polyester with ANSI A2 Cut Resistance with a 10-gauge High-Viz yellow acrylic terry for warmth.
• Smooth blue coated 3/4 nitrile helps keep hands dry.
• Sandy nitrile coating provides superior grip in dry, wet and oily applications.
• Knit wrist helps prevent dirt and debris from entering the glove.

About the 1773
• High-Vis 13-gauge polyester with ANSI A2 Cut Resistance with a 10-gauge High-Viz yellow acrylic terry for warmth.
• Smooth orange coated 3/4 latex helps keep hands dry.
• Sandy latex coating provides superior grip in dry, wet, and oily applications.
• Knit wrist helps prevent dirt and debris from entering the glove.

Both the 1772 and 1773 can be laundered, extending the life of the glove, lowering replacement costs, and offer a color binding on the cuff that indicates the glove size.

The Tillman 1772 and 1773 can be used in many industries, including manufacturing, construction, maintenance, and municipal services. The Tillman 1772 and 1773 is available in five sizes, S- 2XL.

More info www.JTillman.com

Training course to explain new corrosion protection for turbines

Wind Systems staff
-
0
Training course to explain new corrosion protection for turbines

The new corrosion protection coating, “SikaCor® SW-1000 RepaCor,” developed in a research association, promises a significantly simplified, faster, and more cost-effective on-site repair of wind turbines. Following the successful start in February 2018, a free product training course this year in Rostock provides an insight into the possible applications on wind turbines and technical information. The event will again be organized by WindSourcing.com GmbH together with Sika Deutschland GmbH on February 12, 2019 (German) and February 13, 2019 (English) in Rostock.

The four- to five-hour event is aimed at all service companies involved in the maintenance and repair of wind turbines. It consists of a theoretical part and practical exercises.
“The aim is for the participants to be able to reliably use the product themselves after the training and pass on the knowledge to their employees,” said Stefan Weber of WindSourcing.com, managing director of the Hamburg-based trading company. “Various practical applications in recent months have confirmed this: The product is a revolution in the repair of corrosion damage to onshore and offshore wind turbines.”

The use of wind power, especially on the open sea, demands the highest standards of corrosion protection — and thus maintenance — due to the mechanical and climatic conditions.

“A long and thus profitable service life of the turbines can only be achieved with conscientious maintenance,” Weber said. “The systems cannot simply be transported away, especially on the high seas. All work has to be carried out on site in wind and weather — often by industrial climbers who can only handle heavy tools and material to a limited extent.”

The use of wind power, especially on the open sea, demands the highest standards of corrosion protection — and thus maintenance — due to the mechanical and climatic conditions. (Courtesy: WINDSOURCING.COM)

In addition, protective coatings have to dry and harden quickly due to the weather, Weber saod. This is exactly where SikaCor® SW-1000 RepaCor comes into play.

The solvent-free 2-component coating material is the result of the three-year research project RepaKorr, which sought — and found — solutions to the problems mentioned above. The Fraunhofer Institute for Manufacturing Technology and Applied Materials Research (IFAM), among others, was involved in the joint project funded by the Federal Ministry of Education and Research.

Between 2013 and 2016 Sika Deutschland GmbH was in charge of the material requirements and launched SikaCor SW-1000 RepaCor on the market in summer 2017.
“The coating dries four hours faster than conventional systems,” Weber said. “The practical packaging in the form of mixed cartridges facilitates processing and thus guarantees absolute process reliability with minimum waste at the same time. Industrial climbers are thus loaded with low weight.”

Other properties include single-layer performance (corrosion protection as with multi-layer systems), UV and colour stability and Norsok M501 approval with ISO 20340 testing.

On February 21, 2018, WindSourcing.com, together with Sika Deutschland GmbH, welcomed, for the first time, customers from the service sector for wind turbines in Hamburg to present the new corrosion protection SikaCor SW-1000 RepaCor in a product training course. Besides other participants, the team of Christian Schulte, managing director of Windspektrum GmbH, also took part in the training.

“The product training with WindSourcing.com and Sika appealed to my team and me very much,” he said. “The product ‘SikaCor® SW-1000 RepaCor’ was professionally presented. In addition, all participants were able to test the product extensively and direct their questions to the two trainers. The networking on the evening before the training was not neglected either.”

More info deu.sika.com/de/SikaAkademie/Verarbeiter/Windenergie/Windenergy.html

Lidar lights up wind opportunities for Tilt in Australia

Wind Systems staff
-
0
Lidar lights up wind opportunities for Tilt in Australia

Tilt Renewables, a leading developer, owner, and manager of renewable energy generation assets in Australia and New Zealand, has confirmed the use of wind Lidar technology from ZX Lidars to remotely measure wind conditions above ground without the need for a traditional met mast. Initial deployment has been to a remote site in complex terrain primarily for the purpose of confirming the quality of the wind resource.

With more than 1.6 GW of approved wind projects in Australia and New Zealand, Tilt Renewables required a flexible solution to wind-resource assessment that could also be used to bolster existing anemometry and with an eye on operational sites emerging. New Zealand-based wind engineering consultancy Energy3 provided expert advice and support on how to achieve this.

ZX Lidars provides vertical and horizontal profiling wind Lidar to accurately measure wind conditions remotely and ahead of their installed position. (Courtesy: ZX Lidars)

“A key advantage of Lidar is that it can be easily mobilized and rotated to a number of sites within the Tilt Renewables’ portfolio and can be used so flexibly for a range of purposes including feasibility assessments at potential new sites and improving the coverage of site measurements at existing sites,” said Sherrin Yeo, engineering manager at Tilt Renewables.

ZX Lidars provides vertical and horizontal profiling wind Lidar to accurately measure wind conditions remotely and ahead of their installed position. These accurate, independent wind measurements are a cornerstone in the development, construction, and operation of wind farms globally.

More info www.zxlidars.com

Field measurement campaign begins on wind turbine

Wind Systems staff
-
0
Field measurement campaign begins on wind turbine

Three innovative 20-meter-long rotor blades developed within the context of the SmartBlades2 project will be assessed under natural weather and wind conditions in Boulder, Colorado, over four months. For this purpose, the rotor blades, which were designed by the Fraunhofer Institute for Wind Energy Systems (IWES) and built by the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR), have been successfully installed in the United States at the Department of Energy’s National Wind Technology Center (NWTC) of the National Renewable Energy Laboratory (NREL).

Among others, the field campaign aims to clarify how well the rotor blades — designed with bend-twist coupling — are able to effectively dampen peak loads during strongly variable wind speeds. The results will serve as a basis for the further development of smart rotor blades. The SmartBlades2 project is funded by the German Federal Ministry for Economic Affairs and Energy (BMWi) and is being carried out by the Research Alliance Wind Energy, with its partners DLR, Fraunhofer IWES, and ForWind, in collaboration with industry partners from GE, Henkel, Nordex Acciona, SSB Wind Systems, Suzlon, Senvion, and WRD Wobben Research and Development.

Longer service life, greater yield

Rotor blades equipped with bend-twist coupling are able to adapt to variating wind conditions by themselves — at higher wind speeds the rotor blades can bend or twist, thus offering the wind a smaller impact surface. This reduces the overall load on the system, increasing the service life of the wind turbine as well as its power yield. In order to be able to fully capture the structural and aerodynamic behavior of the newly developed blades during the field experiment, the project partners integrated specially developed measurement systems into the blades’ structure already during production at the DLR Center for Lightweight-Production-Technology (ZLP) in Stade, Germany.

First analysis under real weather conditions

“We are very excited to observe and find out how our rotor blades behave during these field assessments. This measurement campaign represents the first practical trial for our blade technology,” said SmartBlades2 Project Manager Zhuzhell Montano Rejas of the DLR Institute of Composite Structures and Adaptive Systems. “The findings will also be used to improve simulation models for next-generation wind turbines.”

Fraunhofer IWES is leading the measurement campaign.

“We are using several measurement systems that will allow us to monitor the entire length of the blades in order to capture the deformations, accelerations, and loads they are subjected to,” said Dr. Christian Kress of Fraunhofer IWES, who is responsible for the campaign. “In addition, the air flow around the rotor blades will be recorded at the surface using an aerodynamic measurement system.”

Inside the rotor blades, various systems designed by DLR, IWES, and SSB Wind Systems will continuously control how the blades behave under the diverse wind loading conditions the turbine will experiment. Furthermore, the turbine’s tower and the nacelle made available by NREL is also equipped with extensive measuring technology, enabling the team to measure the whole system’s behavior in detail.

The resulting measurements will be correlated with data on wind conditions, which will be recorded by the NREL data acquisition systems present on the NWTC’s field and a SpinnerLIDAR (Light Detection And Ranging) measurement device from the Center for Wind Energy Research (ForWind) at the University of Oldenburg. This Lidar is normally installed in the spinner of a wind turbine, but in this case it is set up on top of the nacelle to be able to analyze the wind field both in front and behind the turbine.

With a laser system, the SpinnerLIDAR scans an area of wind field in front of or behind the turbine.

“In this section, the SpinnerLIDAR can measure at over 300 points every second,” said ForWind scientist Prof. Dr. Martin Kühn. “This enables us to measure wind speeds, wind directions, vertical wind shear components, as well as local turbulences with a spatial resolution that cannot be matched with conventional Lidar devices.”

The comparison of the structural behavior measured by the sensors with the wind data will show whether the developed rotor blades achieve the desired behavior. At the beginning of the measurement campaign, the SpinnerLIDAR will measure the incoming wind field while at the end it will also measure the wake flow behind the wind turbine to better understand the influence of the blades on the surrounding environment.

The measurements in the three-bladed Controls Advanced Research Turbine (CART3) provided by NREL, unlike systems used for commercial power generation, will allow the scientists to conduct various validation scenarios, such as an abrupt deceleration of the rotor. On site — on the edge of the Rocky Mountains — the wind conditions can range from very low speeds to powerful gusts in winter and early spring. This will make it possible for the researchers to assess the SmartBlades2 rotor blades under a variety of environmental conditions.

“We are delighted to be able to validate the new rotor blades at our research turbine at the NWTC,” said Andrew Scholbrock, who is responsible for the measurement campaign with the CART3 turbine at NREL. “We are also eager to find out how these rotor blades, designed with bend-twist coupling, perform in practice under real world conditions.”

The partners of the BMWi-funded SmartBlades2 project are hoping that the measurement campaign will yield meaningful findings on the behavior of the new rotor blades. The validation process will start with data analysis while the measurements are still being conducted and will continue until the end of the project, during the autumn of 2019. The project will help to support the wind-energy industry in the further development of rotor blades with bend-twist coupling and is set to pave the way for the implementation of this technology.

More info www.iwes.fraunhofer.de

Enercon using world’s longest semitrailers from Goldhofer

Wind Systems staff
-
0
Enercon using world’s longest semitrailers from Goldhofer

Enercon, Germany’s leading manufacturer of wind-power plants, has added six Goldhofer “VENTUM” flatbed semitrailers with pendular axles to its heavy-duty vehicle fleet. This innovative solution for transporting extremely long rotor blades has a unique five-fold telescopic deck for a total extension length of 72 meters (including gooseneck).

That means the North German wind-power specialists can make use of road transport for the fast and safe delivery of rotor blades in excess of 70 meters. In addition to the lift-and-lowerable, loadable gooseneck, Enercon’s decision was also influenced by Goldhofer’s mature pendular axle technology and the option to add a rail-mounted “BLADEX” blade tip lift.

Transporting such long and large rotor blades reliably and delivering them just in time is an enormously challenging undertaking that Enercon can now handle on an intelligent and flexible basis, according to Hans-Dieter Kettwig and Simon-Hermann Wobben, managing directors of Enercon GmbH. The new Goldhofer “VENTUM” flatbed semitrailers enable Enercon to master all the challenges of long-distance journeys with these exceptional loads.

The »VENTUM« at work. (Courtesy: Enercon)

As the first five-fold extendible semi-trailer on the market, the “VENTUM” permits wind-turbine manufacturers and heavy haulage companies to transport extra-long rotor blades well over 70 meters in length on roads, tracks and construction sites. In combination with Goldhofer’s mature pendular axle technology, the “VENTUM” is the key to fast and safe passage over bridges and round tight bends and roundabouts as well as easy maneuvering on confined construction sites. The hydraulically lift-and-lowerable gooseneck ensures rotor blades with very large hub diameters can safely negotiate tunnels and underpasses. Pendular axles with a stroke of ±300 mm give the vehicle full maneuverability and compensate uneven ground in the longitudinal and transverse directions. Loading height is 1,250 mm. Where required for the route to be taken, ground clearance can be increased over and above the suspension stoke. Two support legs facilitate extension and retraction of the telescopic tubes, which permit the deck behind the gooseneck to be extended from a basic length of 13.5 meters for empty running to more than 68 meters. The steering is adjustable, so the vehicle can be driven in its basic length without a second man in the cab, while optimum cornering performance is available with the deck extended.

“With a steering angle of up to 60 degrees and the user-friendly »SmartControl« remote control system, Goldhofer provides outstanding support for drivers in their task of safely transporting loads of this enormous size to their final destination,” said member of the Goldhofer Board and Head of Transport Technology Rainer Auerbacher.

The gigantic rotor blades are used above all for sites with low wind speeds and also, where there is sufficient hub height, for refurbishing and upgrading existing wind power plants.

More info www.goldhofer.de

RES completes 80 MW Copenhagen wind project in New York

Wind Systems staff
-
0
RES completes 80 MW Copenhagen wind project in New York

RES (Renewable Energy Systems), a leader in the development, engineering, and construction of wind, solar, transmission, and energy storage projects in the Americas recently announced it has completed construction of the Copenhagen wind project, developed and owned by EDF Renewables. The 80-MW wind project in Jefferson and Lewis counties in upstate New York was completed on December 21, 2018.

The Copenhagen Wind Farm is the first wind project that RES has self-performed in the State of New York and consists of 40 Vestas V110 2.0 MW turbines. The construction, which began in 2017, employed more than 300 workers at its peak with 300,000 man-hours of labor completed safely with no lost time injuries in an area that receives one of the highest levels of snowfall in the United States.

The Copenhagen Wind project is the first wind project that RES has self-performed in the State of New York and consists of 40 Vestas V110 2.0 MW turbines. (Courtesy: RES)

Capitalizing on New York’s ambitions for clean-energy development, the project provides an economic investment opportunity as well as an increase in the green jobs quota and is financed through a 15-year Power Purchase Agreement with Narragansett Electric Company, a wholly-owned subsidiary of National Grid.

“RES has met the challenge to deliver clean energy to New York head on,” said Rick Ortiz, RES senior vice president of Wind Construction. “We are proud of working alongside EDF Renewables to make clean energy a reality in New York and are particularly grateful to our team that engaged with the local community.”

By partnering with the local groups in Lewis and Jefferson counties, the project secured a significant level of community involvement. RES employees engaged in various community support initiatives throughout the construction period, including raising more than $2,000 for a shelf stable food drive for senior citizens during the winter months, a donation to build a new playground at a local school, and donating 42 units of blood for the local American Red Cross.

More info www.res-group.com

Vestas receives 122-MW order for project in Iowa

Wind Systems staff
-
0
Vestas receives 122-MW order for project in Iowa

With reference to Vestas Wind Systems A/S’ company announcement No. 22/2016 of June 17, 2016, Vestas has received a 122-MW order from MidAmerican Energy Company, a subsidiary of Berkshire Hathaway Energy, for the Wind XI project in Iowa.

The order includes supply and commissioning of V110-2.0 MW turbines as well as a ten-year Active Output Management 5000 (AOM 5000) service agreement. Deliveries are expected to begin in the third quarter of 2019 while commissioning is planned for fourth quarter of 2019.

More info www.vestas.com

Terra-Gen chooses DEIF for controller upgrades on Pacific Crest farm

Wind Systems staff
-
0
Terra-Gen chooses DEIF for controller upgrades on Pacific Crest farm

The independent power producer Terra-Gen is upgrading 20 Vestas V47 wind turbines on its Pacific Crest wind farm in Tehachapi, California, with a control retrofit solution from the Danish company, DEIF.

The increased demand for competitive power production and the rapid development in the wind industry necessitates that older turbine models such as the Vestas V47 are equipped to meet today’s performance standards.

DEIF’s control retrofit solution extends the turbine lifetime and optimizes the turbine performance in terms of variable speed concepts, extended cut-out and adaptive power setpoint. So far, 20 Vestas V47s on the Pacific Crest Wind Farm will be retrofitted.

DEIF’s control retrofit solution extends the turbine lifetime and optimizes the turbine performance in terms of variable speed concepts, extended cut-out and adaptive power setpoint. (Courtesy: DEIF)

“We strive to run our turbines efficiently — at the lowest cost,” said Ward Scobee, chief operating officer at Terra-Gen. “The Pacific Crest Wind Farm is a high-wind site, and the cost of downtime is critical. So, with the controller upgrade and thus performance optimizations, I am convinced that we will extend turbine lifetime, reduce our downtime, and increase the revenue of the total wind farm.”

With a DEIF retrofit control solution for Vestas V47, the turbines can operate without the VRCC and at the same time run above 600 kW and as close to the rated power level as possible. For Terra-Gen, the retrofit solution from DEIF means they have no VRCC-related costs such as spare parts, lost production due to downtime, and derating, and they aim to reach a three-year ROI.

“The upgrade of the turbines on the Pacific Crest Wind Farm sets new standards for lifetime extension, performance optimization, and secures availability without the VRCC,” said Jean Felber, sales and business development manager at DEIF.

More info www.deif.com

Vestas first company to install 100 GW of wind turbines

Wind Systems staff
-
0
Vestas first company to install 100 GW of wind turbines

Vestas has been a pioneer in wind-energy solutions and a cornerstone in making the world’s energy mix sustainable. In late 2018, a new milestone was reached in that 40-year journey, as Vestas achieved 100 GW of installed wind turbines with the installation of a V110-2.0 MW turbine at MidAmerican Energy’s Wind XI project in Iowa.

Since the inaugural installation of a V10-30 kW turbine in Denmark in 1979, Vestas has installed more than 66,000 turbines in about 80 countries across six continents and has been a key part of taking wind energy from niche to mainstream. Today, Vestas’ largest onshore wind turbine is the V150-4.2 MW turbine, and the 100-GW milestone has thus been made possible by the continuous evolution of the company’s wind-energy technology and solutions, which have seen output and efficiency increase to a level that has made wind energy the cheapest form of electricity in many markets.

Today, Vestas’ largest onshore wind turbine is the V150-4.2 MW turbine. (Courtesy: Vestas)

“We have pioneered wind energy across the globe for 40 years, and to install 100 GW together with our customers and partners is something we are extremely proud of as it underlines how far Vestas and wind energy have come,” said Anders Runevad, Vestas president and CEO. “It’s also a pleasure to celebrate this milestone with a key customer like MidAmerican Energy. Reaching this milestone has required continuous innovation, strong commitment and great execution from all Vestas’ employees, and the 100 GW therefore represents a key part of the foundation that enables us to develop the sustainable energy solutions of the future.”

During the journey to 100 GW, Vestas has helped remove more than 100 million metric tons of CO2 from the atmosphere by providing sustainable and cost-effective solutions to meet the world’s energy demand. By crossing this 100 GW threshold, Vestas has installed approximately 10 percent of the world’s total 1 TW of installed wind- and solar-energy capacity.

The capacity of the Wind XI project will grow to up to 2,000 MW and consist of multiple sites in Iowa placed into service between 2017 and 2019. Powered by V110-2.0 MW turbines built at Vestas’ factories in Colorado, Wind XI will deliver clean, low-cost wind energy to MidAmerican Energy’s customers and communities. Vestas will provide operations and maintenance for Wind XI project sites via long-term AOM 5000 service agreements.

Based on global average electricity, 100 GW of wind energy saves around 129 million metric tons of CO2 annually, equaling CO2 emissions from:
• 141 billion pounds of burned coal.
• 298 million barrels of oil.
• 22.54 million U.S. homes yearly electricity use.
• 33 coal-fired power plants.
• Carbon sequestered from 152 million acres of forest.

More info www.vestas.com

Siemens Gamesa launches 10 MW offshore wind turbine

michele-admin
-
0
Siemens Gamesa launches 10 MW offshore wind turbine

Siemens Gamesa Renewable Energy (SGRE), a world leader in the offshore industry, recently launched the SG 10.0-193 DD, the company’s first 10-plus MW offshore wind turbine. Based on the experience of its previous generations, the newest wind turbine in the SGRE offshore product portfolio builds on proven technology for maximum energy yield at all wind speeds. It offers the same reliability while improving profitability and reducing risk for customers.

“The new SG 10.0-193 DD combines experiences and knowledge from five generations of proven direct drive technology in one 10 MW turbine. A showcase of strong performance, swift time-to-market, and low risk in the offshore wind energy market,” said Markus Tacke, CEO of SGRE.

The 10-MW rating is made possible through a larger generator diameter, building on the proven SGRE Direct Drive generator technology.

By increasing the rotor diameter to 193 meters, this new wind turbine offers up to 30 percent more AEP than its predecessor, the SG 8.0-167 DD. Its 94-meter-long blades provide a swept area of 29,300 square meters.

By increasing the rotor diameter to 193 meters, the SG 10.0-193 DD new wind turbine offers up to 30 percent more AEP than its predecessor, the SG 8.0-167 DD. (Courtesy: Siemens Gamesa)

Each blade is almost the same length as one soccer field.

The technology on the offshore direct drive platform allows for the re-use of most components from previous generations, providing a short time to market. The prototype is expected to be installed in 2019 with commercial market deployment expected in 2022.
“Siemens Gamesa has been applying its knowledge and experience directly into offshore wind turbines for decades,” said Andreas Nauen, CEO of the SGRE Offshore Business Unit. “Utilizing proven components and concepts provides us with a strong, established value chain, with clear processes and skilled employees ready to go, leveraging on a fully- developed and industrialized supply chain.”

The nacelles of this new offshore wind turbine will be initially manufactured at the SGRE factory in Cuxhaven, Germany, the world’s largest plant for offshore wind turbine nacelles.
The annual energy production of one SG 10.0-193 DD is sufficient to supply about 10,000 European households with electricity. This means that an offshore wind park composed of 20 of these turbines would cover the annual electricity consumption of a city the size of Liverpool.

“The Levelized Cost of Energy from offshore wind continues to decrease as industry scale and performance grow,” Nauen said. “New markets are developing across the globe, all of which require cost-efficient, reliable, and clean power for generations. The SG 10.0-193 DD enables us as market leaders to meet these needs in close cooperation with our customers, stakeholders, and society-at-large.”

SGRE has the largest track record in the sector among offshore turbine manufacturers. With a capacity of more than 12.5 GW installed and more than 3,100 offshore wind turbines in operation globally, the company has established itself as the leader in the offshore market. Siemens Gamesa’s experiences reaches back as far as 1991, when it established the world’s first offshore wind park. Through a strong focus on safety and innovation, SGRE constantly strives to reduce the Levelized Cost of Energy from offshore wind power.

More info www.siemensgamesa.com

APAC to lead gearbox, direct-drive markets, says GlobalData

Wind Systems staff
-
0
APAC to lead gearbox, direct-drive markets, says GlobalData

Asia-Pacific (APAC) is expected to lead the global wind gearbox and direct drive equipment markets with a share of 46 percent and 53.5 percent, respectively over the forecast period of 2018 to 2022, said GlobalData, a leading data and analytics company.

The company’s latest report, Wind Gearbox and Direct Drive, Update 2018, reveals the global trends of wind power are creating business opportunities for new and refurbishment markets. It states that prominent markets such as China, the U.S., and E.U., which had made significant strides in the wind market, are creating a significant market for gearbox refurbishments.

Installation of wind gearboxes and direct drive equipment are estimated to aggregate 209.6 GW and 81.3 GW, respectively, over the forecast period.

The total installation of wind gearboxes stood at 37.8 GW in 2017 as compared to 14.4 GW for direct drive, and will continue leading the market over the forecast period. However, due to their improved mechanical design, superior operation, and maintenance aspects, direct drives are likely to experience a higher growth rate over the forecast period. The direct drives market is expected to witness 17.6 GW of installations, i.e., 29.9 percent of the total installation in 2022.

“Within APAC, major countries such as China, India, Australia, and South Korea are likely to boost the growth of the drive-train markets,” said Nirushan Rajasekaram, power analyst at GlobalData. “The market for wind gearboxes in APAC is expected to reach to $1.58 billion in 2022.”

China accounted for 27.3 percent of the global gearbox market value in 2017. The country is committed toward developing its renewable portfolio to sustain development activities and growing electricity demand from the transport sector industries and rural regions to improve standards of living, while reducing power sector emissions. However, the market is projected to decline till 2022, due to change in awarding wind projects from a feed-in tariff model to auctioning model.

“The historical installations of wind turbines in China will see the gearbox refurbishment market value grow significantly over the forecast period,” Rajasekaram said. “India is estimated to be the fastest growing market for gearbox, growing at a CAGR of 15.9 percent over the forecast period. Similar to China, the government proposed ambitious renewable energy targets, which are expected to drive the wind-equipment market. It is likely that direct drives will also see higher rates of deployment in India, during the forecast period.”

However, despite strong projections for wind gearbox and direct drive markets, certain market uncertainties exist. Major countries such as China, the U.S., and Germany are experiencing slowdown in wind-turbine installations, which would directly impact the drive-train market, although opportunities for refurbishment are plenty, owing to their legacy wind turbine installations.

“Evolving power and smart technologies could result in wind power becoming uncompetitive and thereby impact its growth in the future,” Rajasekaram said. “Emerging markets will require the construction of sufficient grid infrastructure to support new generation capacity addition, which could slow market deployment of wind power.”

More info GlobalData.com

Apex Clean Energy sells Sugar Creek Wind farm in Illinois

Wind Systems staff
-
0
Apex Clean Energy sells Sugar Creek Wind farm in Illinois

Apex Clean Energy recently announced the sale of Sugar Creek Wind to a wholly owned subsidiary of Algonquin Power & Utilities Corp.

Sugar Creek Wind is an advanced-stage 202 MW project. (Courtesy: Apex Clean Energy)

The advanced-stage 202 MW project is in Logan County in central Illinois. In fall 2018, Apex secured a long-term contract with the Illinois Power Agency to provide renewable energy certificates to utilities in the state.

“Sugar Creek Wind demonstrates the Apex team’s proven ability to identify and advance projects with strong fundamentals, including access to transmission, exceptional resources, strong community support, and financeable offtake,” said Mark Goodwin, president and CEO of Apex.

More info www.apexcleanenergy.com

Aerox strengthens its global presence in the U.S.

Wind Systems staff
-
0
Aerox strengthens its global presence in the U.S.

Aerox, a Spanish start-up specialized in the design of polymers for the wind-power industry, closed 2018 taking a step further in its ambitious business plan: the opening of its North American branch, Aerox North America LLC.

“The North American wind-power sector is a very dynamic market, highly demanding in terms of quality and service level. It is therefore virtually essential to have a local presence in order to be competitive,” said Raúl Cortés, the company’s CEO. The operation was coordinated by Aktion Legal Partners, a regular adviser to Aerox, and Garrigues through its office in New York.

Aerox’s technology solves some of the greatest challenges faced by the industry today, such as the protection of the leading edge of blades, due to the progressive increase in the size of wind turbines. Aerox has been marketing its products in the U.S. since 2018, and, following the recent opening of its branch, it plans to carry out the strategic implementation of a production unit in the U.S. in 2019. The company has undergone rapid international expansion, with a presence in Europe, Asia (where it already has a logistics center in China) and, finally, North America.

After an initial capital increase in 2015, investors from Tech Transfer UPV, a fund promoted by the Social Council of the Universitat Politècnica de València and the asset manager Clave Mayor, completed the second financing round of the company between 2017 and 2018, with the aim of meeting the needs arising from international expansion. (Courtesy: Aerox)

“Our business plan was to strengthen our supply chain in North America to ensure sustainable growth in this major strategic area for the sector in the coming years,” Cortés said.

The company has raised more than 1.7 million euros between public and private financing since 2017. After an initial capital increase in 2015, investors from Tech Transfer UPV, a fund promoted by the Social Council of the Universitat Politècnica de València and the asset manager Clave Mayor, completed the second financing round of the company between 2017 and 2018, with the aim of meeting the needs arising from international expansion.

In addition to the exponential growth in its turnover, 2018 was a successful year for Aerox’s new developments. Aerox received 1 million euros of financing in the first half of the year by the European Union’s SME Instrument H2020 for its LEP4BLADES project, which focuses on the industrial scaling of Aerox’s most disruptive innovation: A patented technology to protect the leading edge of wind turbine blades working under extreme operating conditions. This helps extend the wind turbine blade service life up to three times, compared to other solutions on the market.

More info www.aerox.es

620 MW of new wind from Enel Green Power now online in U.S.

Wind Systems staff
-
0
620 MW of new wind from Enel Green Power now online in U.S.

Enel, through its U.S. renewable company Enel Green Power North America, Inc., has started operations of the 320 MW Rattlesnake Creek wind farm, its first wind facility in the state of Nebraska, and the Diamond Vista wind farm of about 300 MW in Kansas. Combined, the two new wind farms will generate about 2,600 GWh annually. With these two wind farms, the total renewable capacity that Enel Green Power has connected to grids around the world this year amounts to approximately 2.6 GW, of which more than 830 MW is in North America.

“With the completion of Rattlesnake Creek and Diamond Vista, we have now added more than 800 MW of new wind capacity in 2018 in the U.S., strengthening our growth in the country and confirming our position as partner of choice for commercial and industrial customers,” said Antonio Cammisecra, head of Enel Green Power. “These projects further demonstrate our ability to develop customized solutions that best meet the renewable energy needs of our customers.”

The Rattlesnake Creek wind farm in Dixon County, Nebraska, is fully contracted with long-term power purchase agreements, under which Adobe will purchase the energy from a 10 MW portion through 2028, and Facebook will gradually buy the wind farm’s full output by 2029. The agreement enables Facebook to power its data center in Papillion, Nebraska, with 100 percent renewable energy. The investment in the construction of Rattlesnake Creek, which is expected to generate about 1,300 GWh annually, amounts to approximately $430 million.

EGPNA, part of Enel Green Power, is a leading owner and operator of renewable energy plants in North America with projects operating and under development in 24 states and two Canadian provinces. (Courtesy: Enel Green Power)

The Diamond Vista wind farm in Marion and Dickinson counties, Kansas, is supported by three separate long-term power purchase agreements. The electricity and renewable energy credits from a 100 MW portion of the wind farm will be sold to global manufacturing company Kohler Co. to supply 100 percent of the annual electricity needed to power the company’s U.S. and Canadian operations, including its 85 manufacturing facilities, offices, and warehouses, while reducing Kohler’s global greenhouse gas emissions by more than 25 percent. Additionally, the output and renewable energy credits from another 100 MW portion of the facility will be sold to City Utilities of Springfield, and those from an 84 MW portion to Tri-County Electric Cooperative of Oklahoma. The investment in the construction of Diamond Vista, which is also expected to generate about 1,300 GWh annually, amounts to about $400 million.

In addition, EGPNA signed tax equity agreements with Bank of America Merrill Lynch and J.P. Morgan for the Rattlesnake Creek and Diamond Vista wind farms. The two investment banks will purchase 100 percent of the “Class B” equity interests of the 320 MW Rattlesnake Creek wind project in Nebraska for about $334 million. Under a separate agreement, Bank of America Merrill Lynch and J.P. Morgan will also purchase 100 percent of the “Class B” equity interests of the 300 MW Diamond Vista wind project in Kansas for about $317 million. Enel retains 100 percent ownership of the “Class A” interests, as well as control over the management and operation of both wind farms.

Over the past year, Enel signed about 570 MW of commercial and industrial (C&I) PPAs in the U.S. To date, Enel has signed, directly or indirectly, more than 1.2 GW of power supply contracts in the U.S. with C&I customers. Through these agreements, Enel is able to create tailor-made solutions for its corporate customers, with the aim to provide them with long-term access to an affordable, sustainable and reliable source of power.

EGPNA, part of Enel Green Power, is a leading owner and operator of renewable energy plants in North America with projects operating and under development in 24 states and two Canadian provinces. EGPNA operates about 100 plants with a managed capacity of about 5 GW powered by renewable hydropower, wind, geothermal, and solar energy. In 2017, the company was the fastest-growing renewable energy company in the U.S., bringing approximately 1.2 GW of capacity online. The company is the largest wind operator in Kansas and Oklahoma.

Enel Green Power is the Enel Group’s business line dedicated to the development and operation of renewables across the world, with a presence in Europe, the Americas, Asia, Africa, and Oceania. Enel Green Power is a global leader in the green energy sector with a managed capacity of about 43 GW across a generation mix that includes wind, solar, geothermal, and hydropower, and is at the forefront of integrating innovative technologies into renewable power plants.

More info www.enel.com

Conversation with Gordon Randall

Wind Systems staff
-
0
Conversation with Gordon Randall

What’s a typical day like for you at ArcVera?
It varies a lot, depending on the project in question that’s going on at the time. But, in a typical day, it’s a mixture of project work, typically analysis, either data analysis or other information analysis for clients, and then internal work, trying to apply what we’ve learned to make our internal processes better, and offer new things that our clients want.

We’re always trying to learn from the industry and learn some information and see what’s new that people haven’t thought of that may be relevant either now or a few years in the future, and try to improve what we can offer to fit that.

What does ArcVera offer the wind industry?
As we’re primarily a consulting organization, and a small but full-service consulting organization, we’re mostly focused on developer and investor clients, helping them understand projects so they can make good decisions. We help them understand how new projects are likely to operate and how to operate their existing ones better.

What drew you to ArcVera?
A lot of it was a combination of the size of the organization, the flexibility of the organization, and the level of experience of the other members of the organization. I’d been in large, bureaucratic, inflexible companies in the past, and it’s often hard to do things, and in some cases hard to give good products to clients when you’re in an organization that’s too large and too slow to move. ArcVera is small, but everyone involved has been in the industry for quite a while, and we’re able to provide our clients with results that sometimes large organizations would have a lot of trouble doing.

How did your previous experience help prepare you for this position at ArcVera?
I’ve been in the wind industry for quite a while now. I started in 2000 at a small consulting organization that became a very large one. So, I’ve been in a similar spot in a small but growing company. Also, more recently, I’ve been on the other side of the business working for a large owner-operator. I’m returning to where I started and have seen it from a couple of different sides now. I have the experience of being with a small organization that’s gone through growing pains and can help ensure the organization stays on track as it grows.

ArcVera Renewables provides high-quality technical services for wind and solar energy.

What do you hope to accomplish for the wind industry through your new position with ArcVera?
I think the one thing that has been a consistent theme throughout my time in the industry is that there are always lessons to learn. There’s a tendency for people to focus on what the industry looked like a few years ago. In the amount of time it takes to learn what the wind is on site or how a specific turbine model operates or how best to operate a project, a lot of those things are based on information that’s from projects that are several years old, and a lot of the time people don’t think of how that’s going to change over time.

We’re seeing a big change now with higher hub heights and larger turbines. I think what we want to do, and what ArcVera focuses on, is not apply lessons to what we know from projects five years ago, but what they’re going to be like five years from now. Industry should be looking at how the meteorology is different at higher heights, how turbines will operate in different climates, and applying that also on a worldwide scale. We should be figuring out what we can learn and take away from what we’ve seen in the U.S. and apply it to wind projects in other developing countries.

Any particular challenges that you’ve already tackled at ArcVera in the wind industry?
This goes to my comment about industry focusing on the past. I think that there are so many projects that the industry hasn’t solved, just because, by the time they’ve been solved, they will have changed for the next set of projects.

So, I think the challenges that are most interesting — and that will continue to change — are things like wake effects and turbine power performance. They’re interesting because I don’t think they’re ever fully solved. As turbines change and they’re put in different locations, different wind regimes, there’ll always be something else to learn. The trick is figuring out what it is that we don’t know. Those are the types of issues I’ve always been most intrigued by and spent the most time studying.

How do you look into that crystal ball, if you will, and see what to expect on a project, and not rely on older data that may be obsolete?
A lot of it is that sometimes there’s a focus on, for example, looking at meteorological data, of looking just at a single project data set. But what we’re beginning to learn now is, there are so many projects, and so many different sources of data, that we see things that present larger patterns. We’re getting more data from devices like Lidar that measures 200 meters up into the atmosphere. They’re starting to tell a story that we can extrapolate and start using to inform our judgments about an entire region, if it’s the Great Plains, or Texas, or wherever.

We’re making interpretations from those, and changing how we do things, like flow modeling or wake modeling. In some cases, it is a bit of a guess or a look into a crystal ball, but I’d like to think it is more of an interpretation of a large body of data and educated guesses.

Moving beyond that, where do you see wind in the next 10 to 20 years, and ArcVera’s place in that future?
There’s not going to be any slowdown when you look over a long period. There’ll be different countries, different individuals, and there’ll be pushbacks, obviously with the end of the PTC coming up in the U.S. that will slow things down. There’s a consensus worldwide that renewables are the way to go, not just because of issues like climate change, but because they are the cheapest way to produce electricity.

It’s more that we’re going to expand into new places, to have new challenges, whether it’s in other countries that may not have the same infrastructure, or may not have the same types of information available, meteorological data or performance information, things like that. There will be all of those issues that we’ve figured out in the U.S., that we’ll then have coming up again in other parts of the world. ArcVera has a strong presence around the world, so we’re well suited to help with the growth of renewable energy as it continues to expand on all of the continents.

But, here in the U.S., I think it’ll just be continued growth in certain areas, and in some cases there’ll be new challenges, as projects go into more densely populated areas, and different concerns from landowners and nearby residences, or just into areas that people haven’t looked at for wind. Because up until recently, it hasn’t been economically viable in the Southeast, for example. We’ll start going into places like Arkansas and the Carolinas where there will continue to be interesting new challenges, and it will just be from continued growth.

Do you consider U.S. offshore the next big thing here?
Looking out 20 years, I can’t see that the U.S. will have the same density of offshore as, say, offshore in the U.K. or in the North Sea. But it’s a thing that’s coming.

More info: www.arcvera.com

CloudVisit Energy

Kenneth Carter
-
0
CloudVisit Energy

Wind farms are often in remote areas that aren’t always easily accessible. And once at a site, wind technicians still have to fight the elements at heights upward of 300 feet.

Bottom line: inspecting a wind turbine is hard work. CloudVisit Energy, however, is working to make some of that labor a little easier and more efficient.

As renewable energy becomes more economical, it continues to grow by leaps and bounds. But as it grows, the machinery becomes more intricate, and the need to inspect and maintain that equipment becomes even more essential.

With CloudVisit Energy’s remote inspection software, a technician is able to have a virtual staff at his fingertips.

Daniel Gilbert, president, CEO, and founder of CloudVisit Energy, was able to parlay his experience in the telecommunication field to the inspection and maintenance of wind turbines.

“In 2016, we were contacted by a major publicly traded telecommunications company, Ericsson,” he said. “The system that we developed for them is used for the remote inspection of mobile communication systems. Ericsson is a world leader in developing and manufacturing all the radios and the infrastructure that runs mobile phone systems.”
Wind, Gilbert discovered, was no different.

With CloudVisit Energy’s remote inspection software, a technician is able to have a virtual staff at his fingertips. (Photos courtesy: CloudVisit Energy)

Industry similarities

“There are a lot of similarities between that industry and the wind industry. You’re dealing with generally inaccessible locations, and the installation and maintenance projects are similar, too,” he said. “This type of work is very skilled and requires multiple skillsets.”

CloudVisit Energy’s software enables a division of labor. Using this software, the technician doing the installation of the equipment does the work, and the inspector with the expertise in inspecting the construction and completion of projects is at a central office connected to the technician in the tower, according to Gilbert.

“Our system enables the inspector to connect directly with the technician doing the work,” he said. “It can be very hard to find a technician who also has the equivalent skills as an inspector. That’s the similarity that we saw in the industries, and with my interests in wind and renewable energy, it was a natural progression.”

And Gilbert said his company’s software can be used in many industries, as well as the spectrum of wind-based energy: onshore and offshore.

Customizable

“Our system is a customizable cloud-based software solution that optimizes the efficiency and safety of these projects,” Gilbert said. “Our system ensures that the industry continues to expand efficiently, safely, and cost-effectively by using this tool. But we have worked on major infrastructure projects for so long, we understand how the work can be delegated and separated between remote inspectors and people on site.”

CloudVisit Energy developed a customizable workflow for wind energy based on the company’s experience with the telecommunications industry, according to Gilbert.
“The emphasis is on collaboration, and our system is really a tool, and the collaboration between the inspector at the main office and the technician is what drives efficiencies and gets the work done correctly,” he said.

Part of the collaboration is a video conferencing link between the operator and the technician that works with low bandwidths, which is crucial for remote sites, according to Gilbert.

With CloudVisit Energy’s software, a technician doing equipment installation does the work, and the experienced inspector is at a central office connected to the technician in the tower.

Software backbone

“Collaboration is a huge aspect, and it’s the backbone of the software,” said Genevieve Pfeiffer, content marketing manager with CloudVisit Energy.

Industry-specific functionalities exist to ensure everyone stays focused and keeps records, according to Pfeiffer.

“We have the video conferencing aspect, but there’s a lot more,” she said. “We also have different functionalities, such as a multipurpose checklist. This allows the experts, who are remotely working, to create a checklist, which serves as a punch-list for on-site technicians. The inspection can’t be verified until everything’s done and signed off on.”

Along with the video conferencing, the software allows high-definition images to be taken as well, according to Pfeiffer.

“Inspectors can annotate those pictures,” she said. “They can draw on them to make specific points on the picture stand out and make notes on those as well. Those are just a few of those functionalities. There are a lot more, but we think that those combined with the video conferencing are what really makes the software stand out.”
Gilbert agreed.

“Having those kinds of records are essential,” he said. “If there are issues found at a later time, you have a detailed record of the project from the beginning. It’s the combination of the collaboration and the functionality and the workflow, which again reflects our deep understanding of large infrastructure projects.”

Pfeiffer added that this combination is essential with large projects made up of massive labor and heavy machinery.

Software training

CloudVisit Energy’s software is a first important step, but it doesn’t end there. Training and working with clients on the software is also key, according to Gilbert.

“Our software is a tool, and the tool is only as good as the people that use it,” he said. “So, we really focus on working directly with a client on training, on adopting and ensuring that the tool is being embraced and used correctly. Because, ultimately, the utilization and the correct use of the system is what’s going to drive efficiencies, improve outcomes, lower costs, and improve safety. We really focus on understanding the client’s requirements, their priorities, and developing a phased implementation. We offer the full spectrum of support, which includes training and ongoing updates to the workflow of the system. So, we really become part of the team.”

A video conferencing link between the operator and the technician works with low bandwidths.

15-year mark

CloudVisit Energy recently marked its 15th year in the business in January, and Gilbert noted that he’s found it interesting that many industries share the same challenges.
“I see there are a lot of industries that think the problems they have are unique to them, but really there are a lot of similarities in a lot of the issues,” he said. “That really was the genesis of our software.”

And it all grew from CloudVisit Energy’s relationship with Ericsson.

“Our work in the telecom industry is really over the top,” Gilbert said. “I think it’s very significant, the work that we’ve done with Ericsson. It’s been significant working with one of the global leaders in telecommunications. They’re using our system, which is really the foundation for their global sales and services. It’s very transformative to be part of that. Our system is being used now for current installations, but it’s going to play a major role in 5G rollout.”

Gilbert said he has a close affinity with the wind industry, and he sees it as a renaissance of sorts on the horizon of the U.S.’s energy future.

“For the time being, fossil fuels and natural gas are going to play a part, but I would hope that as wind technology becomes more common, the cost will come down, and the benefits will become greater. In terms of a company, our product map is very focused on the technology adoption with the first version of our system that involves human operators,” he said. “Then the next iteration would be combining augmented reality with drones.”

Nurturing wind

Gilbert has a passion for the wind industry, and he and his company are working hard to ensure this form of renewable energy flourishes and continues to grow.

“It’s obviously beneficial to the environment; it’s good for the economy; there have been a lot of studies that show investments in renewable energy and wind have a much higher multiplier than similar investments in petroleum, oil exploration, and mining,” he said. “In terms of the macro picture, we need more of these projects, because ultimately, they drive innovation; they create jobs; they’re good for the environment, and they’re good for the country, and they’re good for our security. Overall, the result is in the creation of better-paying jobs. It’s just a win-win outcome for everyone, and that’s one reason why we’re so interested to really see these projects become more ubiquitous.”

And CloudVisit Energy’s software can help drive that future, according to Gilbert.

“We’re at the crossroads of really great opportunities, and we have developed a tool that can drive innovation and the utilization of wind energy,” he said. “It’s really just a great time.”

The state of the art of gearboxes

michele-admin
-
0
The state of the art of gearboxes

Much has been written about the global growth in the wind turbine industry. Today, more than 341,320 wind turbines are operating worldwide. In particular, the number of offshore installations has exploded in the past seven years (Figures 1-2).

Production of gearboxes for wind turbines. Today’s gearbox normally requires a major scheduled maintenance only after seven to 10 years, typically for bearing replacement. (Courtesy: Shutterstock)

The continuous reliability gains in the industry have caused the cost of wind-turbine electricity to drop significantly, so much so that some current offshore projects are underway without any government subsidy, with full understanding of the unique maintenance issues and costs associated with offshore installations. This momentum is proof of how far wind turbines have come in terms of reliability and cost effectiveness.

 

 

Figure 1: Installed global wind capacity in megawatts (Global Wind Energy Council).

Time Between Maintenance: Lubricant

In regard to the wind-turbine gearbox, gone are the epidemic failure rates of less than three years seen in the early 2000s. Rather, today’s gearbox normally requires a major scheduled maintenance only after seven to 10 years, typically for bearing replacement. And remember, this is a scheduled maintenance, not a replacement of a failed gearbox.

Figure 2: Cumulative offshore capacity in megawatts (Global Wind Energy Council).

Unfortunately, the wind-turbine gearbox lubricant and filtration system has not achieved a similar increase in durability. A maximum of three to five years is the typical life expectancy for the lubricant and even less for the lubricant filters. As a result, major efforts are under way to increase the life expectancy of the lubricant. Approaches such as improved filtration, lower lubricant operating temperatures, and newer formulations have all been and continue to be studied in this effort. The goal is to increase the time between maintenance for the lubricant to match or exceed that for the gearbox.

In particular, lubricant debris generated from the gear teeth during start up and operation is a major cause of lubricant deterioration. Despite all the improvements in gear design and manufacturing, wind-turbine gear teeth continue to rub (i.e. operated in mixed EHL) and release hard iron metal particles into the lubricant. These metal particles rapidly clog the filters if they are large enough to be captured. Unfortunately, many are too small to be filtered out. These unfilterable small particles, typically 1-5 microns in size, create numerous lubricant problems. For instance, very large pressure peaks are produced when a small hard metal particle passes through the contact zone of a gear or bearing, as represented in Figures 3-4.

Figure 3: Schematic of a contact zone containing a hard metal particle and its resulting pressure peak.

Along with denting or abrading the tribological surface of the given component, which leads to a further increase in mixed EHL, the particles result in high pressure peaks that accelerate the surface fatigue of the gear or bearing. In fact, some experts believe the high pressure peaks from metal particles in bearing contacts lead to or contribute to the problem of axial fatigue cracking in today’s wind-turbine industry (T. Stalin; Vattenfall; NREL/GRC presentation February 2018).

Further problems develop when small iron particles combine with other lubricant materials to form large, soft conglomerates. These conglomerates accelerate the clogging of the filters. And remember, once the filter is clogged, the filter bypass automatically opens, and all filtration is lost until the filters can be changed.

Figure 4: Image of the pressure peak caused by a hard particle in a contact zone.

Also, small metal particles in the presence of the high lubricant operating temperatures are catalysts for numerous deteriorating side chemical reactions. In particular, water in the high temperature lubricant, down to even 100 ppm, is an excellent ingredient to react with iron particles and some of the special lubricant additives. Many wind turbines are operating with 1-2 percent water content in their lubricant along with >1,000 ppm of small iron particles. This is an excellent incubator for deteriorating chemical side reactions.

A New Approach

It is understandable that wind-turbine lubricant filtration, lowering operating temperatures, and new formulations have gotten the initial industry focus to increase the time between lubricant maintenance. Much has already been accomplished in these areas, but there are limits that these approaches can accomplish and most improvements have already been achieved.

A different approach has been proposed, and its study has begun. Rather than accepting the problems associated with the teeth generating hard iron particle debris, the goal is to eliminate the tooth debris altogether. This approach is using the ISF® process to superfinish all the gears throughout the gearbox.

Figure 5: Three multi-megawatt class isotropic superfinished planets removed after seven years of operation.

Historically, isotropic superfinishing has been applied only to the input stage of a wind-turbine gearbox such as the annulus, sun pinion, and planets. These are the slowest moving and highest loaded gears and experience the most amount of surface distress. Commercial experience since 2003 has proved that isotropic superfinished wind-turbine gears do not develop surface distress, even after many years of operation. So it is expected that fully isotropic superfinished wind-turbine gearboxes will achieve the same result.

Figures 5-6 depict a set of multi-mega wind turbine planets that were originally isotropic superfinished by the manufacturer. The “galvanized” tooth surface appearance is the normal burnished appearance. These planets had been removed after seven years of operation for bearing maintenance and were returned to operation without any repair. Note there is no metal-to-metal contact pattern on the tooth flanks. This is proof that these isotropic superfinished planets were, and are continuing to operate, in full EHL. In other words, the planet teeth are not rubbing against the sun pinion or annulus teeth and no iron particle debris is being generated.

Figure 6: Closeup of the top planet after seven years showing no metal-to-metal contact pattern.

Summary

The new study will use a series of gearboxes where all the gears are isotropic superfinished. These gearboxes will be placed in operation and carefully monitored for particle debris generation. After a period of time, if all goes well, the original filters will be upgraded with finer particle filters to remove even the smallest of debris. (Remember, even 1-micron particle debris can damage the bearings in a wind turbine gearbox.) Then the wind turbines will be allowed to continue operating indefinitely, and the condition of the lubricant will be monitored.

Hopefully, the lubricant will remain fully operational for seven or more years, and the time between maintenance for the gearbox, its lubricant and filter will be extended and balanced. This study will take many years to complete. Periodically, progress reports will be published to the wind-turbine industry on this effort.

EDITOR PICKS

POPULAR POSTS

POPULAR CATEGORY

Popular Columns

© 2018 Media Solutions inc. All rights reserved