Study: Wind resource assessments reach 100% mean accuracy


ArcVera Renewables, a leading provider of consulting and technical services for wind and solar projects with more than 30 years of experience, recently developed and published an ambitious benchmark report aimed to deliver a thorough analysis of the performance of its wind-energy resource assessment (WERA) practice across a broad range of operating wind projects.

Based on a dataset composed of 31 projects it worked on in the United States, combining 3.5 GW of installed capacity and 212 years of operation, the report provides a detailed comparison between the pre-construction assessments using ArcVera’s advanced WERA practices and the actual post-construction energy production data.

To improve the accuracy of its energy-yield estimates, ArcVera Renewables has used high resolution mesoscale wind flow modeling in its Wind Energy Resource Assessment (WERA) methodology since 2012. Pictured is a hub-height wind speed map created using a full physics, 200-meter resolution mesoscale model run, down-scaled to 30-meter resolution terrain. The range of wind speeds shown in the image is 4-8 m/s. (Courtesy: ArcVera Renewables)

The results of the study show that ArcVera’s wind-assessment techniques are accurate to within about 1 percent on average of reported project P50 energy production, which becomes near zero mean bias after accounting for grid curtailment. In addition, the benchmark study indicated that ArcVera’s wind assessments have lower individual project performance variation than in the past. With an average project performance bias close to zero, ArcVera’s advanced methodology yields an average project performance of 98.8 percent for the 31 projects. Given that estimates of grid curtailment losses, typically at 1 to 1.5 percent, are not corrected for in most benchmark assessments, ArcVera’s overall project performance is effectively 100 percent in terms of accuracy.

What’s more impressive, the results show the risk of building a wind farm that significantly over- or under-performs is limited by applying ArcVera’s techniques, with an industry-leading 4.7 percent standard deviation of project performance. No firm is currently assessing wind farms with the accuracy achieved by ArcVera.

“For over 30 years, ArcVera Renewables has provided finance-grade consulting and technical services for wind- and solar-energy clients worldwide, including the very first bankable WERA delivered in 1989 in California,” said John Bosche, president and principal engineer at ArcVera Renewables. “Our track record is second to none, and we wanted to make public the data that supports that claim. We have consistently delivered accurate and bankable insights backed by advanced technical expertise and decades of global experience. That kind of highly specialized services is what you need to make sure that confident project development decisions are taken, maximum technically-driven advantage is secured, and performance risk is minimized.”