PORTLAND, Ore. (Clean Edge) -- Clean Edge and Nasdaq's three benchmark clean-tech stock indexes all experienced losses last week with the Nasdaq Clean Edge Green Energy Index (CELS) down 6.55%, the Nasdaq OMX Clean Edge Global Wind Energy Index (QWND) losing 4.89%, and the Nasdaq OMX Clean Edge Smart Grid Infrastructure Index (QGRD) 6.08% lower from the previous week.

The overall market saw similar movement -- the S&P 500 lost 4.23%, Nasdaq retracted 5.02%, and AMEX Oil was 4.26% lower from the previous week.

CELS -- down 6.55% for the week but still 8.49% higher than a year ago -- tracks U.S.-listed clean-energy companies and is divided into four categories: advanced materials; energy intelligence; energy storage and conversion; and renewable electricity generation and renewable fuels. Of the 53 total component securities, two experienced gains and 51 lost ground from the previous week's close.

CELS' best performer for the week was solar manufacturing equipment provider GT Solar International ( SOLR), gaining 2.76%. Rounding out the top five CELS performers were semiconductor maker Fairchild Semiconductor ( FCS), up 0.82%; power management integrated circuit maker National Semiconductor ( NSM), lower by 0.71%; integrated circuit maker O2Micro International ( OIIM), falling 1.7%; and integrated circuit manufacturer Linear Technology ( LTC), down 1.92%.

CELS' worst performer last week was energy storage product maker A123 Systems (AONE), declining 20.68%. Other poor performers included Chinese solar cell manufacturer JA Solar Holdings (JASO), falling 17.24%; stationary fuel cell developer FuelCell Energy (FCEL), losing 14.29%; vertically integrated solar product and service company SunPower Corporation (SPRWRA), down 14.02%; and PV laminate maker Energy Conversion Devices (ENER), losing 13.17%.

QWND -- down 4.89% last week and 25.11% lower in the last 12 months -- includes companies that are primarily manufacturers, developers, distributors, installers and users of energy derived from wind sources. Of QWND's 21 pure-play components, four experienced gains and 17 saw losses last week.

QWND's best pure-play performer for the week was wind farm owner and operator Terna Energy ( TENERGY ), up 5.06%. Other top pure-play performers included wind farm developer Greentech Energy Systems ( GES), gaining 2.67%; wind turbine manufacturer Nordex, rising 1.41%; composite material developer Gurit Holding ( GUR), growing 0.26%; and renewable energy developer Gamesa Corporacion Tecnologica ( GAM), down 0.86% for the week.

QWND's worst pure-play performers were wind-power producer China Longyuan Power Group , declining 12.33%; wind-turbine part supplier China High Speed Transmission Equipment Group (0658), down 11.97%; wind energy product and service provider Broadwind Energy ( BWEN - Get Report), losing 11.90%; wind power generator Japan Wind Development (2766), declining 11.67%; and wind project owner and operator China Windpower Group (0182), down 9.76% from the previous week.

QGRD -- down 6.08% from the previous week -- is composed of companies that are primarily involved in the electric grid; electric meters, devices and networks; energy storage and management; and enabling software used by the smart grid and electric infrastructure sector. Last week, two of the 21 pure-play QGRD components saw gains while the remaining 19 lost ground.

QGRD's best pure-play performer was Italy-based utility cable provider Prysmian (PRY), gaining 4.83%. Rounding out the top five pure-play performers were communication network equipment provider RuggedCom (RCM), up 0.10%; energy management service provider EnerNOC (ENOC), down 3.50%; solar inverter maker SMA Solar Technology (S92), 3.58% lower; and electricity distribution and automation management company Schneider Electric (SU), losing 5.07%.

QGRD's worst performers included electrical infrastructure specialty contractor MYR Group (MYRG), losing 12.53%; energy management service provider PowerSecure International (POWR), down 12.24%; large-scale power conversion technology provider Satcon Technology (SATC), retreating 11.52%; Chinese distribution transformer maker Jinpan International (JST), down 11.46%; and demand energy management company Comverge (COMV), lower by 11.40%.

This information is not intended to be used as a guide to investing, and the authors make no guarantees that any investments based on the information contained herein will benefit you in specific applications, owing to the risk that is involved in investing of almost any kind. For more on Clean Edge's stock indexes, including methodology, components, historical performance, financial products and licensing information, please visit www.cleanedge.com/ceindex.

Clean Edge, Inc., founded in 2000, is the world's first research and publishing firm devoted to the clean-tech sector. The company, via its publications, events, and online services, helps companies, investors, and governments understand and profit from clean technologies. Clean Edge, with offices in the San Francisco Bay Area and Portland Oregon, offers insight and intelligence on emerging clean-tech trends, opportunities, and challenges. The company publishes a range of reports including the annual Clean Energy Trends and Clean Tech Job Trends report series; hosts the annual Clean-Tech Investor Summit (along with IBF); maintains a number of benchmark clean-tech stock indices with NASDAQ OMX including CELS, QGRD, and QWND; and produces Clean Edge Jobs, a leading online jobs board for clean-tech job seekers, employers, and recruiters. To keep abreast of the latest clean-tech news; access industry reports; learn more about our services; or sign up for our free e-newsletters; visit CleanEdge.com.