Clean Edge and Nasdaq's three benchmark clean-tech stock indexes each fell last week with the Nasdaq Clean Edge Green Energy Index ( CELS) down 2.83 percent, the Nasdaq OMX Clean Edge Global Wind Energy Index ( QWND) 4.93 percent lower, and the Nasdaq OMX Clean Edge Smart Grid Infrastructure Index ( QGRD) retreating 5.55 percent higher from the previous week. The overall market also moved lower. The S&P 500 lost 1.79 percent and Nasdaq fell 2.29 percent, while AMEX Oil was 0.63 percent lower from the previous week. CELS - down 2.83 percent for the week but 13.27 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, five experienced gains, 45 lost ground, and one remained unchanged for the week. CELS' best performer for the week was electric vehicle manufacturer Tesla Motors ( TSLA), gaining 22.209 percent. Rounding out the top five CELS performers were solar energy product maker Energy Conversion Devices ( ENER), up 14.57 percent; semiconductor manufacturer Microsemi ( MSCC) , higher by 6.94 percent; utility network provider ESCO Technologies ( ESE), up 3.57 percent; and wafer manufacturer MEMC Electronic Materials ( WFR), 2.12 percent higher for the week. CELS' worst performer last week was biomaterials developer Metabolix ( MBLX) , declining 25.14 percent. Other poor performers included solar module encapsulant maker STR Holdings ( STRI), losing 21.45 percent; demand management service provider Comverge ( COMV), down 20.67percent; Chinese solar produce manufacturer Solarfun Power Holdings ( SOLF), retreating 17.86 percent; and demand management firm EnerNOC ( ENOC), 17.77 percent lower. QWND - 4.93 percent lower last week and 36.51 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, three saw gains while 15 experienced losses. QWND's best pure play performer for the week was wind power generator Japan Wind Development Co. (2766), up 9.65 percent. Other top pure play performers included renewable power developer Gamesa Corporacion Tecnologica ( GAM), gaining 4.99 percent; wind turbine gearbox maker Hansen Transmissions International ( HSN), rising 1.58 percent; wind turbine manufacturer Vestas Wind Systems ( VWS), losing 1.15 percent; and wind project developer China WindPower Group (0182), down 1.23 percent for the week.