“The claim that wind projects in the U.S. are achieving 30% average capacity factors nationally [are] … not meaningful when considering that state RPS mandates are based on local resources. For states like New York and Pennsylvania, where average capacity factors are in the low- to mid- 20% range, many more wind turbines and related infrastructure (transmission) will be needed to meet RPS mandates than originally forecasted, resulting in increased costs and impacts.
Couple this with the fact that wind production in most states is seasonal with summer months producing at half that of winter months and also concentrated during periods of low demand (night time) — much of the energy arrives as excess energy making it less useful.”
This week, the U.S. Department of Energy announced it was revisiting the conclusions of its 2008 report, 20% Wind Energy by 2030.
The study, produced in cooperation with the American Wind Energy Association (AWEA) and other stakeholders, explored a modeled energy scenario in which wind could supply 20% of the nation’s electricity by 2030. DOE made clear in the report that the 20% scenario was neither a prediction nor a goal, but, for wind proponents, the study served as the foundation for ongoing advocacy.
20% wind power by 2030 became a call to action and more. Absent a national renewables standard, AWEA heralded the 20% as a de facto mandate for wind.
The industry insists it’s on track to reach 20% wind (up from 4% today), but such claims are neither realistic nor wise. Despite explosive growth in new wind installations in the last five years alone,  challenges to further development have become more evident and will ultimately limit wind’s expansion.
An Unpopular Wind
Since 2008, thousands of turbines have been sited in communities across the U.S. As more towers were erected, public acceptance of the massive facilities started to drop.
Earlier this year, both New Hampshire and Vermont sought statewide moratoria on wind farm development until the impacts could be better understood. Law suits are now pending against proposed and operating wind facilities in at least six state courts as well as at the federal level.  Ohio , North Carolina, and others are revisiting their renewables mandates after wind has failed to deliver lower energy prices and jobs.
And this week, the reality of big wind splashed across media screens worldwide when AP reported that in Wyoming “a soaring golden eagle slams into a wind farm’s spinning turbine [about once a month] and falls, mangled and lifeless, to the ground.”
The public is increasingly wary of the wind industry’s tactics and so is Congress. The 1-year, $12 billion extension of the wind production tax credit (PTC) secretly added to the Fiscal Cliff bill in January underscored how unpopular wind energy is on Capitol Hill. The PTC would likely not survive a floor vote.
Wind’s Lack of Capacity
According to DOE’s 2008 report, U.S. demand for electricity would reach 5.8 billion megawatt-hours (MWh) by 2030.  In order for wind to satisfy 20% (or 1.16-billion MWh) of this demand , 305,000 MW of installed wind operating at an annual average capacity factor of 43.4% would be needed. Yet, few existing wind plants in the U.S. come close to producing at this level.
The 2011 Wind Technologies Market Report “found that average capacity factors have been largely stagnant among projects built from 2006 through 2010″  at around 30%. In 2011, wind speeds improved raising the average capacity factor to 33%.
We examined 2012 monthly wind production data for 450+ operating wind plants in 34 states representing more than 40,000 MWs of installed capacity. All projects we looked at were in service for the entire year of 2012. The map below (clearer picture here) offers key insight into the effectiveness of wind at meeting demand by state.
Only three states, Nebraska, South Dakota, and Oklahoma achieved average capacity factors over 40%. Most states, including California, produced at under 30%.
Regional variations in production were also pronounced with the lowest average capacity factors found on both the east and west coasts and the highest capacity factors, by state, found in the mountain and plain regions, correlating closely with NREL wind maps.
The claim that wind projects in the U.S. are achieving 30% average capacity factors nationally may be accurate but not meaningful when considering that state RPS mandates are based on local resources. For states like New York and Pennsylvania, where average capacity factors are in the low- to mid- 20% range, many more wind turbines and related infrastructure (transmission) will be needed to meet RPS mandates than originally forecasted. resulting in increased costs and impacts.
Couple this with the fact that wind production in most states is seasonal with summer months producing at half that of winter months and also concentrated during periods of low demand (night time) — much of the energy arrives as excess energy making it less useful.
The Role of Government Subsidies
More than half of the installed wind in the U.S. when measured in megawatts was built under the Section 1603 grant program which imposed no performance criteria on projects. Instead, the program substituted government largess for private investment, but with no accountability. Developers were rewarded for building turbines even in areas with marginal winds. The race to place projects in service before the end of 2012 was more about collecting 1603 grant money than producing quality wind facilities. Wind performance data for 2013 and 2014 will reveal how much this will be a factor in lowering capacity factors.
The DOE is now stating that its revised report on wind energy will study U.S. energy policy as opposed to promoting it. “We want to deal in the realities [of the technology] and we also want to be sensitive to the concerns of the DOE’s sister agencies,” said Jose Zayas, the DOE’s director of the wind and water power technologies office.
Such would be a deviation from DOE’s aggressive promotion of wind energy. It’s essential the Department of Energy provide independent and comprehensive analysis that acknowledges the limitations and risks of relying on largely unpredictable and non-dispatchable energy sources. The public deserves answers and not unrealistic advocacy.
 At the end of 2007, installed wind in the U.S was about 16,500 MW. At the end of 2012, wind installations were at 60,000 MW.
 New York, Nevada, Washington, Michigan, Maine, California.
 Given the precipitous decline in electricity demand since 2008, these figures will likely be throttled back in any revised study by DOE.
 Some of the reduced performance could be tied to transmission curtailment but this information is not publicly available.
The ‘re-study’ by DOE will be welcome. Perhaps it’ll afford the opportunity to discuss a complementary (primary) metric more meaningful to the question of meeting load than capcity factor. As Lisa points out, seasonal variation in wind renders moot the points claimed by wind proponents that “there’s enough wind to [satisfy] x% of domestic electricity…” Until and unless we start using a power-centric metric (like capacity credit, like capacity value, like dependable on-peak capacity) that’s tied to peak load [not some dressed up short time frame average capcity factor] in probabalistic terms, I fear the de-evolution of electricity policy and technology will continue.
Who, with any knowledge of the US electricity grid, could possibly have imagined that an expensive, intermittent, non-dispatchable source of electricity would not be the ideal replacement for low cost, reliable, dispatchable generation? (sarc off)
The environmental community has been complicit in the politicization of climate science, which is at best speculative. However, it appears now that it has also been complicit in the politicization of engineering, which is far less speculative.
To Tom Tanton – isn’t the use of incremental Effective Load Carrying Capacity the most effective and descriptive way to judge wind the same as all other generators? It’s my understanding that it only measures value during highest loads (peak and near-peaks), so it could also give a reasonable approximation of impact on operating reserves. Regulation impact is another story. But by tying wind output to real loads, it at least represents a more realistic grid/system impact.
To the Lisa Linowes – my cynical side taunts me into believing this study will expand on an analysis from NREL and Berkeley Lab early last year which concluded great progress was being made in the amount of land area meeting or exceeding capacity factor and LCOE thresholds. I think the baseline was early 2000s. It also threw in the caveat of onshore projects increasingly shifting towards lower wind regime areas, due to transmission and policy (permitting?) constraints. My point is that it might be too much to expect the follow up analysis of the 20% Wind report to deviate very far from other modern analysis. Maybe we’ll be surprised….
Maine has only one wind site, Mars Hill, that averages over 30%. Even with Mars Hill included, the average for all of 2012 for the wind sites that were greater than 20MW that had to report data to FERC was less than 25%. The statistical table is at this link: http://www.windtaskforce.org/profiles/blogs/maine-wind-sites-production-for-entire-year-2012 It includes the tally of ARRA Sec. 1603 grants as well as reports on substantially higher earnings for sites with a PPA compared to earnings as a merchant generator. We in Maine predicted this miserable production when the wind industry was touting 35%
There is no question that some engineering firms have succumbed to politics with a little monetary lubrication, but, the infestation doesn’t stop there.
[…] http://www.masterresource.org/2013/05/wind-performing-badly/#more-25620 […]
Thank you for presenting the CF data. Especially, I like the US CF map. What an eye opener. Even legislators will understand it, if they made and effort.
There is little to be gained by explaining to lay people how larger quantities of variable, intermittent wind energy create havoc on various US grids; eyes glaze over. Some grids are better capable of dealing with it than others.
It is much better to approach it from the CF angle; dismal CFs means dismal economics, i.e., high energy prices.
Here is an article with CFs from around the world: http://theenergycollective.com/willem-post/169521/wind-turbine-energy-capacity-less-estimated
@JohninMA: ELCC is one good approach and is essentially same as the ‘dependable on peak capacity’ I began using circa 1987, provided it is calculataed based on several years of operating data, not on predictions…
@Tom Tanton – I guess I see the generic reference to ‘capacity factor’ as too decoupled from actual costs (operating to meet demand). After all, if a PV installation’s and a wind farm’s capacity factors are in the same range, it is entirely likely the PV farm has a better ELCC given how its output tends to match peaks.
In a somewhat similar vein, we’ve seen the output portion of coal plants rise versus nat gas, in the last year or less. While fuel costs, base demand levels, etc., are big factors, my point is the usage doesn’t correlate well to CF even in the case of dispatchable facilities. CF is a good, anecdotal way to explain a drawback for wind systems. But it really doesn’t do a very good job of explaining network impacts it seems.