Clean Edge and Nasdaq's three benchmark clean-tech stock indices experienced mild movement last week with the Nasdaq Clean Edge Green Energy Index (CELS) up 1.39%, the Nasdaq OMX Clean Edge Global Wind Energy Index (QWND) growing 1.95, and the Nasdaq OMX Clean Edge Smart Grid Infrastructure Index (QGRD) essentially unchanged at 0.02% lower from the previous week.The overall market was also slightly positive -- the S&P 500 gained 1.82%, Nasdaq grew 1.50%, and AMEX Oil was 4.27% higher from the previous week. CELS -- up 1.39% for the week and 1.80% 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, 29 experienced gains, 23 experienced losses, and one ended the week unchanged. CELS' best performer for the week was PV manufacturing equipment provider GT Solar ( SOLR), gaining 10.88%. Rounding out the top five CELS performers were vertically integrated PV product maker Solarfun Power Holdings ( SOLF), up 12.68%; solar wafer and module manufacturer LDK Solar ( LDK), higher by 12.56%; solar cell and module product maker Canadian Solar (CSIQ), rising 10.41%; and PV module encapsulant maker STR Holdings ( STRI), up 10.40%. CELS' worst performer last week was electric motor maker UQM Technologies (UQM), declining 11.88%. Other worst performers included solar and LED manufacturing equipment provider Veeco Instruments (VECO), losing 7.83%; utility-scale renewable energy project integrator Satcon Technology (SATC), down 6.72%; demand energy management company Comverge (COMV), retreating 6.55%; and solar manufacturing equipment provider Aixtron (AIXG), 6.47% higher. QWND -- up 1.95% last week but 28.57% 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, seven experienced gains and 14 lost ground. QWND's best pure play performer for the week was Denmark-based renewable energy developer Greentech Energy Systems ( GES), up 10.88%. Other top pure play performers included wind turbine manufacturer Vestas Wind Systems , gaining 7.30%; wind farm developer China Longyuan Power Group (0916), rising 2.70%; Australian wind farm developer Infigen Energy ( IFN), growing 2.56%; and wind turbine gearbox supplier Hansen Transmission International , 1.91% higher. QWND's worst pure play performers were wind power project developer and operator Japan Wind Development Co. (2766), losing 12.14%; carbon fiber material composite developer Gurit Holding (GUR), down 5.66%; wind energy product and service provider Broadwind Energy (BWEN), losing 4.36%; Greece-based renewable energy project developer (TENERGY), declining 4.23%; and renewable energy project developer Gamesa Corporacion Tecnologica (GAM), falling 3.43% from the previous week.