New study explains trends in wind turbine prices over past decade

This executive summary is for a cost-of-wind study by Lawrence Berkeley National Laboratory

Since 2008, wind turbine prices in the U.S. have fallen by nearly one-third on average. In conjunction with improvements in turbine design and performance, falling turbine prices enable the latest generation of wind power projects to profitably sell electricity at prices well below what was common several years ago. Although this unfolding development has the makings of an R&D and market success story, the facts are nevertheless a bit more complicated, given that the turbine price decline since 2008 began from elevated levels, after turbine prices had doubled in the period from 2002 through 2008.

These two substantial and opposing trends over the past decade – and particularly the earlier doubling – run counter to the smooth, gradually declining technology-cost trajectories that are often assumed by energy-analysts modeling the diffusion of new technologies, including wind power. Understanding and explaining this notable discrepancy between theory and historical reality is the primary motivation behind a new report released by Lawrence Berkeley National Laboratory titled, “Understanding Trends in Wind Turbine Prices Over the Past Decade.”

The report examines seven drivers of wind-turbine prices in the United States, with the goal of estimating the degree to which each contributed to the doubling in turbine prices from 2002 through 2008, as well as the subsequent decline in prices through 2010. In aggregate, these seven drivers – which include changes in labor costs, warranty provisions, manufacturer profitability, turbine scaling, raw-materials prices, energy prices, and foreign exchange rates – explain from 70% to 90% (depending on the year) of empirically observed wind-turbine price movements through 2010.

Turbine scaling – the rapid increase in average turbine capacity, hub height, and rotor diameter over this period – is found to have been the largest contributor to the turbine price doubling through 2008 and has continued to pressure prices higher to this day (2011). The cost of scaling is not without benefit, however, according to Berkeley Lab research scientist Mark Bolinger, one of the study’s authors. “Although larger and taller turbines do cost more per kilowatt of rated capacity, they are also generally able to access better wind conditions and capture more of the wind’s energy, resulting in higher capacity factors and a lower overall cost of electricity.” Scaling-related turbine cost increases can, therefore, be viewed as a reasoned approach to minimizing the levelized cost of wind energy.

An extended period of U.S. dollar weakness – which likely increased the dollar-denominated price of turbines and components imported into the U.S. – is estimated to have been the second-largest contributor to the turbine price doubling through 2008. The risk of further dollar weakness pressuring turbine prices higher, however, has been somewhat mitigated by greater localization of the supply chain in recent years. “Almost two-thirds of the cost of an average turbine installed in the U.S. today comes from domestically manufactured components, up from roughly one-third just five years ago,” says Berkeley Lab staff scientist and report co-author Ryan Wiser. “This increase in domestic content reduces foreign exchange rate risk and transportation costs.”

Changes in labor costs, warranty provisions, manufacturer profitability, and raw material prices are all found to have had lesser – though not inconsequential – impacts on turbine prices, while changes in energy prices had only a negligible impact.

According to the authors, this work has important implications for the wind industry, policymakers, R&D-program managers, and energy analysts. With the wind industry only recently becoming a serious contributor to the power sector in the U.S. and globally, it must take care to ensure that cost reductions remain the rule, and that unexpected cost inflation does not price wind out of the market, leading to demand destruction. Policymakers who count on wind to provide a growing share of the world’s electricity needs – and who enact policies aimed to achieve that goal – want reassurances that wind can meet this challenge in a cost-effective manner (and perhaps that wind will be able to wean itself off of direct public policy support altogether). R&D managers need to understand past cost trends to target future research most effectively. Finally, energy analysts who have heretofore relied on the simple application of “learning curve theory” to project future technology costs must potentially reevaluate their beliefs and develop a more nuanced understanding of the drivers of wind (and other forms of) power costs.

The report was funded by the Wind & Water Power Program in the U.S. Department of Energy’s Office of Energy Efficiency and Renewable Energy. The full report “Understanding Trends in Wind Turbine Prices Over the Past Decade” and a presentation slide deck that summarizes the report can be downloaded from:

http://eetd.lbl.gov/ea/ems/re-pubs.html

Lawrence Berkeley National Laboratory