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.