Clean Edge and Nasdaq's three benchmark clean-tech stock indexes ended the week higher with the Nasdaq Clean Edge Green Energy Index ( CELS) up 8.07 percent, the Nasdaq OMX Clean Edge Global Wind Energy Index ( QWND) growing 3.53 percent, and the Nasdaq OMX Clean Edge Smart Grid Infrastructure Index ( QGRD) 6.24 percent higher from the previous week. The overall market saw similar movement. The S&P 500 gained 3.55 percent, Nasdaq grew 4.15 percent, and AMEX Oil was 2.59 percent higher from the previous week. CELS --- up 8.07 percent for the week and 4.99 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 53 total component securities, 49 saw gains and four, losses. CELS' best performer for the week was utility network provider ESCO Technologies ( ESE), gaining 21.12 percent. Rounding out the top five CELS performers were carbon fiber composite material developer Zoltek Companies ( ZOLT), up 20.29 percent; power management device maker Power-One ( PWER), higher by 20 percent; PV product maker Solarfun Power ( SOLF), rising 18.02 percent; and LED and solar manufacturing equipment provider Veeco Instruments ( VECO), up 16.46 percent. CELS' worst performer last week was smart meter manufacturer Itron ( ITRI), declining 3.77 percent. Other poor performers included stationary fuel cell developer FuelCell Energy ( FCEL) , losing 2.44 percent; electric motor maker UQM Technologies ( UQM), down 1.67 percent; vertically integrated solar product manufacturer SunPower Corporation ( SPWRA), retreating 0.07 percent; and integrated semiconductor maker IXYS ( IXYS) , 0.81 percent higher. QWND -- up 3.53 percent last week but 28.68 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 21 pure play components, 13 experienced gains, 7 lost ground, and one ended the week unchanged. QWND's best pure play performer for the week was wind power project developer and operator Japan Wind Development ( 2766), up 50.78 percent. Other top pure play performers included Zoltek Companies, gaining 20.29 percent; energy delivery technology developer American Superconductor ( AMSC), rising 11.57 percent; wind turbine parts maker China High Speed Transmission Equipment Group ( 0658), growing 11.47 percent; and wind farm developer China Longyuan Power Group ( 0916), 10.07 percent higher. QWND's worst pure play performers were Greece-based renewable energy project developer TENERGY, losing 3.88 percent; wind turbine gearbox maker Hansen Transmission International ( HSN), down 3 percent; Spain-based renewable energy developer Iberdrola Renovables ( IBR) , losing 1.11 percent; wind turbine manufacturer Clipper Windpower ( CWP), declining 1.05 percent; and Spain-based renewable energy producer EDP Renovaveis ( EDPR), falling 0.62 percent from the previous week.