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Can small wind certification buoy U.S. consumer confidence?

Larry Sherwood

Spurred by eligibility criteria to access a growing number of financial incentives the small wind industry is making solid headway toward consistent ratings, reliable performance estimates, and demonstrated compliance with safety standards.

With record applications in New York for on-site wind turbine rebates prompting a funding increase in May, combined with recent suspensions of similar programs in California and New Jersey addressing performance and safety concerns, the pressure is mounting on small wind manufacturers to hasten their efforts to complete independent testing and secure certification labels.

First limited certifications

The Small Wind Certification Council (SWCC) has taken recent actions to advance the transition of the market and allow ‘apples to apples’ comparison for consumers and funding agencies, including granting Conditional Temporary Certification to threewind  turbine models.

This SWCC status indicates the turbine has been tested and certified under the UK’s Microgeneration Certification Scheme, but certain requirements of the American Wind Energy Association (AWEA) Small Wind Turbine Performance and Safety Standard have not been met. The Applicant may also need to satisfy additional requirements within the 18-month Conditional Certification period to be eligible for full SWCC Certification and consumer labels with ratings.

In addition, field testing is complete or nearly complete for several wind turbine models. SWCC expects to certify up to 9 wind turbines, representing a significant share of the North American small wind market by December 31, 2011.

To increase transparency and public disclosure of key milestones in the process, SWCC is now revealing when its pending applicants are ‘Under Test’ and have submitted test and analysis reports for review. SWCC’s website reports the dates that 7 wind turbine models, in addition to the two with Conditional Temporary Certification, achieved ‘Under Test’ status. An additional 16 wind turbine models are currently ‘Under Contract’ with an executed agreement pursuing certification by SWCC.

Recognizing that small wind incentives are often based on power performance ratings and estimates, SWCC’s Board of Directors approved offering a new optional service to applicants of Limited Power Performance Certification for small wind turbine models that have completed power performance testing in accordance with SWCC and AWEA Standard requirements.

While power performance field testing can be completed relatively quickly, the time required for duration testing can result in a lengthy process. If full SWCC certification is not granted within an 18-month period, the limited certification of the turbine’s power curve and annual estimated production terminates.

Shifting policy

Certification Despite the economic slowdown and fluctuating commercial wind market, small wind turbine sales have continued to show impressive growth in recent years. While the U.S. Federal investment tax credit (ITC) expanded under the 2009 American Recovery and Reinvestment Act has aided the domestic market, improved state incentives and interconnection policies have also played a role in building consumer demand.

However, the continued expansion of the industry hinges on improved performance and safety records. The growth of small wind is often tied to incentives, and agencies and utilities providing funding for small wind systems are asking for greater assurance of safety and functionality to justify their investments.

The New York State Energy Research and Development Authority (NYSERDA), which has led the way in setting strict eligibility criteria, has added US$1.4 million for the next 6 months to its wind incentive program that has already paid out US$3.6m in rebates to 92 homeowners, farmers, businesses and municipalities. The current version of NYSERDA’s ‘on-site’ wind program is on track to be the most popular ever, with 33 applications received since October 2010.

The California Energy Commission (CEC) also saw a big surge of interest in small wind and received 314 applications in the past year, about 6 times the state’s previous annual small wind installation rate. However, about 85% of the requests totaling US$6.7m were for rebate amounts close or equal to the total installed cost of the systems.

The pressure is mounting on small wind manufacturers to hasten their efforts to complete independent testing and secure certification labels.

Realising that consumers and installers had little interest in verifying whether systems would generate enough electricity to provide benefit, the CEC announced a ‘time out’ to get the program back on track.

Unfortunately, the suspension of the nation’s longest-running small wind incentive has penalised the entire industry. Basing incentive levels on certified power performance ratings – and setting a cap on the portion of system costs that rebates off set – can avert such problems and prevent ‘free’ turbine sales. SWCC is actively working with the CEC as well as the US Department of Agriculture, Massachusetts, and other state programs to incorporate certification requirements into small wind turbine funding programs to establish consistency in turbine ratings.

NYSERDA now requires certification either by SWCC or other independent certifying agencies, an EN45011 accredited international organization, or a Nationally Recognised Testing Laboratory for turbines not already on their approved list to qualify for rebates. Numerous other state and utility programs rely on the NYSERDA list to qualify small wind turbines for incentives.

Recent equipment failures and malfunctions in New Jersey led to a temporary freeze of its rebates for small wind turbines, although the state’s Board of Public Utilities has now lifted the hold on 9 models after collecting substantial additional documentation on each manufacturer’s field experience.

Still, few of the small wind turbine models on the market have been field-tested or independently valuated, leaving early customers to serve as beta testers. The inevitable breakdowns and disappointed customers have hindered the expansion of the small wind industry.

Market transition underway

Small wind incentive programs in states have disbursed more than US$28m during the past decade, funding more than 12 MW across more than 1300 installations.

Despite the economic slowdown and fluctuating commercial wind market, small wind turbine sales have continued to show impressive growth in recent years.

Programs in Oregon and Wisconsin have set a deadline of January 1, 2012 for wind turbines to be certified to be eligible for incentives. The Massachusetts Clean Energy Center now requires either SWCC certification or NYSERDA qualification. Programs in California, Colorado, Iowa, Maine, Maryland, Minnesota, Nevada, and Vermont have indicated their intention to follow suit.

SWCC’s Incentives webpage provides further background about eligibility criteria and direct links to several programs requiring or expecting to require certification. SWCC has developed options for agencies and utilities to consider for incorporating certification requirements and structuring incentives, including suggestions for wind turbines with a swept area of more than 200 m2 and therefore outside the scope of the AWEA Standard.

A US Department of Energy (DoE) funded project led by eFormative Options is also developing ‘best practice’ recommendations for small wind policies based on a web-based comparison tool of financial impacts on a variety of leading small wind turbine models. The project is designed to aid DoE reach its goal to expand the number of distributed wind turbines deployed domestically fivefold by 2015, and highlight attractive markets and policy targets that offer the quickest return on investment.

The project’s web-based policy comparison tool allows users to examine policies that have the most (and least) impact on improving the bottom line of small wind turbines providing power for on-site use. The tool and accompanying guidebook, to be released in mid-2011, demonstrate how various policy combinations impact project economics to aid policymakers and utilities in determining the cost-effectiveness of incentive programs. For example, impacts on small wind economics for various feed-in tariff levels can be examined.

An increasing number of small wind manufacturers affected by the adverse consequences of fl awed and inconsistent performance reports are recognizing the urgent need for certification, backing SWCC’s efforts to create a robust certification and consumer labeling program.

Incentive managers have indicated certification could help expand their programs for small wind by providing greater assurance of safety, functionality and durability of the projects they fund. Certification can also help inform consumers about their choices.

SWCC issues certified turbines easy-to-understand labels with power performance and sound ratings, confirming that the turbine meets durability and safety requirements. As turbines are certified, SWCC’s web directory will include power curves and other technical information for each model granted certification.

SWCC does not conduct tests, but verifies and certifies test results submitted by testing organizations. Eligible turbines are electricity-producing wind turbines with a swept area up to 200 m2 (2150 ft2), or a rotor diameter of about 16 m (52 ft). Depending on the turbine design, this maximum size is a turbine producing about 50-65 kW. Both horizontal and vertical axis turbines are eligible to apply for certification.

Testing a small wind turbine to the requirements of the AWEA Standard can take at least 6 months. Depending on the wind regime at the test facility, testing and reporting may take as much as two years to complete.

The small wind industry’s rapid growth in recent years is on a trajectory to surpass DoE’s goal of 12,000 wind turbines installed annually by 2015.

Incentives have played a major part in this growth, as has consumer acceptance. Certified power ratings are poised to help sustain public and ratepayer funding and continue building consumer confidence to ensure the future of the small wind market.


Larry Sherwood is President of renewable energy consulting firm Sherwood Associates, and has over 30 years of experience in the field. He is also Executive Director of the Small Wind Certification Council and the Editor of the Interstate Renewable Energy Council’s Small Wind Newsletter. Sherwood is furthermore the Project Administrator for the Solar America Board for Codes and Standards.

Published originally in Renewable Energy Focus U.S. (no longer published), May/June 2011

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renelaserna said

04 March 2012
Your article is very helpful especially to me who is looking for a reliable small wind power supplier for home application. Please send me some of your approved manufacturers here in the U.S.

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