Abstract Results

EXPANDING SMALL WIND TURBINE CERTIFICATION TESTING -

ESTABLISHMENT OF REGIONAL TEST CENTERS

Tony Jimenez, Amy Bowen, Trudy Forsyth, Arlinda Huskey, Karin Sinclair, Jeroen van Dam (NREL),

Joe Smith (Windward Engineering)

The rapid growth of the small wind turbine (SWT) market is attracting numerous entrants. Small wind turbine purchasers now have many options but often lack information (such as third-party certification) to select a quality turbine. Most

SWTs do not have third-party certification due to the expense and difficulty of the certification process. Until recently, the only SWT certification bodies were in Europe. In North America, testing has been limited to U.S. Department of

Energy (DOE) subsidized tests conducted at the National Wind Technology Center (NWTC) under the ongoing Independent Testing Project.

Within the past few years, the DOE, National Renewable Energy Lab (NREL), and some states have worked with the North American SWT industry to create an SWT certification infrastructure. The goal is to increase the number of

certified turbines and gain greater consumer confidence in SWT technology. The American Wind Energy Association (AWEA) released AWEA Small Wind Turbine Performance and Safety Standard (AWEA Standard 9.1 – 2009) in

December 2009. The Small Wind Certification Council (SWCC), a North American certification body, began accepting applications for certification to the AWEA standard in February 2010.

To reduce certification testing costs, DOE/NREL is assisting in establishing a network of Regional Test Centers (RTCs) to conduct SWT third-party certification testing. To jump-start these RTCs, DOE/NREL is providing financial and

technical assistance for an initial round of tests. The goal is to establish a lower-cost U.S. small wind testing capability that will lead to increased SWT certification. This poster describes the project, describes how it fits within broader

SWT certification activities, and provides current status.

• May 2009: RTC Project announced

Project purpose: 

To expand SWT testing capabilities in the United States to allow cost-effective SWT certification testing 

(SWTs are defined as having a rotor-swept area < 200 m2).

Strategy

• Establish RTCs capable of testing small wind turbines to the IEC’s and AWEA’s test standards

• Select RTC partners via competitive solicitation

• DOE/NREL contribute funds and provide technical assistance to RTCs 

• Leverage existing NREL test expertise by assigning an NREL test engineer to each RTC to provide 

i t d t i i t t d i i i l d i d t dt t t

DOE/NREL

• Subcontract 

management

• Technical assistance 

and oversight

RTC

• Set up a test site (facilities, staff, 

equipment)

• Install and commission the SWT

• Conduct the testing

• Write the test reports

• Publish the test report in the public 

domain

Funds

Turbine to be tested

Test and commissioning plans

Test reports

Test and commissioning plans

Regional Test Center Project

Timeline

Conclusions

May 2009: RTC Project announced

• October 2009: RFP released

• December 2009: RFP closed

• February 2010: Offerors selected for 

negotiations

• 2Q 2010: Subcontracts signed

• 3Q-4Q 2010: Turbines commissioned and 

testing initiated

• 2011-2012: Testing completed; test reports 

posted

assistance and mentoring, review test and commissioning plans, and review data and test reports

• Host an annual SWT Certification Testing Workshop

• Support the testing of two turbines per RTC to the standards.

Status

• Four offerors have been selected for negotiations: Intertek (NY), Kansas State University & Colby 

Community College(KS), West Texas A&M (TX), Windward Engineering (UT). Negotiations are underway.

Small Wind Turbine Manufacturer

• Turbine installation 

• Turbine maintenance

Turbine documentation Test reports

Regional Test Center Partners Kansas State University and Colby Community College (Colby, KS) eg o a est Ce te a t e s Intertek (Syracuse, NY)

Windward Engineering (Spanish Fork, UT) West Texas A&M (Canyon, TX)

West Texas A&M University small wind turbine test field. PIX# 17242.

Certification Goals: 

• Provides consumers with objective information about SWT 

performance.

• Provides data needed to objectively determine turbine eligibility 

for state incentive programs.

• Sets a minimum safety level.

Turbine Eligibility Criteria: 

• Rotor-swept area less than 200 m2

• Generates electricity for use while grid-interconnected or for 

SWT Certification Overview

Wind Turbine 

M ft

Turbine to be 

Tested Testing Entity

Duration (IEC 61400-2): 

• Investigates structural integrity and material degradation (corrosion, 

cracks, deformations); quality of environmental protection of the 

wind turbine; and the dynamic behavior of the turbine

• “Turbines must achieve an operational time fraction of at least 90% 

over a minimum of 2,500 operating hours (over a range of wind 

speeds) with no major failures, significant degradation of wind 

turbine components, or “degradation in power production at 

comparable wind speeds.”

SWT Certification Process

Certification Tests

Whisper H40 at the host site, Spanish Fork, Utah. PIX# 10509. 

y

y g

battery charging.

Wind Turbine Manufacturer:

Provides a turbine model to be certified. 

Testing Entity:

Conducts the testing mandated by the test standard. Depending 

on the standard, the testing entity may be an accredited lab, an 

unaccredited lab, or the turbine manufacturer.

Standards Development Body (IEC, AWEA):

Determines how the turbines will be evaluated. Typically 

evaluation consists of a combination of design review and field 

testing The standards are developed and updated using a

Issue 

Certificate

Standards 

Development Body

(IEC, AWEA)

Manufacturer

Certification Body

Test Results

Test 

Standards

Test Results

Design Data

Test 

Standards

IEC 61400-2 Ed.2 Design requirements for small wind turbines, Section 9.4 (Page 99)

Power Performance (IEC 61400-12-1):

• Measures output of the turbine vs. wind speed

• Estimates the turbine’s annual energy production

• Provides an independent check of the manufacturers’ claimed 

performance.

Safety and Function (IEC 61400-2): 

Verifies that the wind turbine displays the behavior predicted in the 

design and that provisions relating to personnel safety are properly 

implemented.

The information contained in this poster is subject to a government license | WINDPOWER 2010 | Dallas, TX | May 23 – 26, 2010 | NREL/PO-7A2-47970

NREL is a national laboratory of the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, operated by the Alliance for Sustainable Energy, LLC.

testing. The standards are developed and updated using a

consensus process by a group representing various stakeholders. 

The base SWT test standards consist of IEC 61400-2, IEC 61400-

11, and IEC 61400-12-1. Most existing country standards are 

based on these IEC standards.

Certification Body (Agency):

• Conducts the design review

• Evaluates the test results and the testing entity

• Grants (or withholds) certification.

(, )

Note: While this diagram shows the certification body conducting its work after

testing, in practice the certification body will often work in parallel with the testing

entity. This ensures issues are resolved in a timely fashion, saving time and

money. Also, in addition to evaluating the turbine design and the test results, the

certification body will evaluate the testing entity and its procedures. Nonaccredited labs and manufacturers testing their own turbines will be subjected to

greater scrutiny than accredited labs.

IEC 61400-2 Ed.2 Design requirements for small wind turbines, Section 9.6 (Page 107)

Acoustic Noise Emissions (IEC 61400-11): 

• Determines the turbine’s noise-emission characteristics

• Is mandatory under the AWEA standard. If not testing to the AWEA 

standard, may or may not be required depending on the certification 

body.