Clean Edge and Nasdaq's three benchmark clean-tech stock indexes were mixed last week with the Nasdaq Clean Edge Green Energy Index ( CELS) up 0.75 percent, the Nasdaq OMX Clean Edge Global Wind Energy Index ( QWND) falling 1.96 percent, and the Nasdaq OMX Clean Edge Smart Grid Infrastructure Index ( QGRD) 2.31 percent lower from the previous week.

The overall market saw similar movement. The S&P 500 gained 0.02 percent and Nasdaq was up 1.13 percent - while the AMEX Oil fell 0.69 percent from the previous week.

CELS -- up 0.75 percent for the week and 10.68 percent 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 51 total component securities, 23 gained while 28 lost ground for the week.

CELS' best performer for the week was semiconductor maker Fairchild Semiconductor ( FCS), gaining 6.52 percent.

Rounding out the top five CELS performers were solar manufacturing equipment provider VECO ( VECO), up 6.19 percent; solar wafer and module manufacturer LDK Solar ( LDK), higher by 5.87 percent; energy storage technology developer A123 Systems ( AONE), up 5.77 percent; and electric vehicle manufacturer Tesla Motors ( TSLA), 5.41 percent higher.

CELS' worst performer last week was ethanol producer Green Plains Renewable Energy ( GPRE), declining 9.68 percent.

Other worst performers included utility network infrastructure product provider Echelon Corporation ( ELON), losing 8.06 percent; lithium-ion battery system maker Ener1 ( HEV), down 7.89 percent; renewable energy project integrator SatCon Technology ( SATC), retreating 6.93 percent; and biomaterial developer Metabolix ( MBLX), 5.99 percent lower.

QWND -- down 1.96 percent last week and 34.86 percent 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 18 pure play components, four saw gains, 12 lost ground, and two ended the week unchanged.

QWND's best pure play performer for the week was wind farm owner and operator Infigen Energy ( IFN), up 21.31 percent.

Other top pure play performers included wind turbine gearbox maker Hansen Transmissions International ( HSN), gaining 7.95 percent; composite material developer Gurit Holding ( GUR), rising 4.27 percent; renewable energy power producer EDF Energies Nouvelles ( EEN), growing 3.97 percent; and wind farm developer China Longyuan Power Group (0916), unchanged for the week.

QWND's worst pure play performers were wind power generator Japan Wind Development Co. (2766), losing 18.04 percent; wind turbine maker Vestas Wind Systems ( VWS), down 15.14 percent; wind turbine manufacturer Nordex ( NDX1), losing 4.13 percent; wind gear transmission equipment developer China High Speed Transmission Equipment Group (0658), declining 3.77 percent; and wind project developer China WindPower Group (0182), falling 3.66 percent from the previous week.

QGRD -- 2.31 percent lower from the previous week but 6.26 percent higher than a year ago -- 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.

Of 22 pure play components, nine experienced positive movement while 13 saw losses on the week.

QGRD's best pure play performer was communication equipment maker RuggedCom ( RCM), up 9.05 percent for the week.

Rounding out the top five pure play performers were solar inverter maker SMA Solar Technology (S92), gaining 2.79 percent; transmission grid owner and operator ITC Holdings ( ITC), rising 2.64 percent; utility contractor Pike Electric ( PIKE), 2.02 percent higher; and utility contractor Quanta Services ( PWR), higher by 1.34 percent.

QGRD's worst performers included energy storage technology developer NGK Insulators (53330), losing 20.95 percent; Echelon Corporation, down 8.06 percent; SatCon Technology, down 6.93 percent; energy and utility service provider PowerSecure International ( POWR), lower by 4.18 percent; and demand management service provider Comverge ( COMV), falling 3.77 percent.

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.

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