QWND's worst pure play performers were wind farm owner and operator Terna Energy (TENERGY), declining 14.22%; Spain-based renewable energy developer Iberdrola Renovables (IBR), down 3.35%; wind turbine manufacturer Clipper Windpower (CWP), losing 1.20%; wind power producer China Longyuan Power Group (0916), declining 0.38%; and wind farm developer Greentech Energy Systems (GES), unchanged for the week. QGRD -- up 5.92% from the previous week - 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. Last week, 16 of the 21 pure play QGRD components saw gains while the remaining five lost ground. QGRD's best pure play performer was American Superconductor, gaining 23.59%. Rounding out the top five pure play performers were energy management service provider PowerSecure International ( POWR), up 14.33%; utility industry contractor Quanta Services (PWR), up 14.03%; electrical infrastructure specialty contractor MYR Group ( MYRG), 13.44% higher; and demand energy management company EnerNOC ( ENOC), gaining 11.89%. QGRD's worst performers included solar inverter maker SMA Solar Technology (S92), losing 8.19%; Comverge, down 2.71%; communication network equipment provider RuggedCom ( RCM), retreating 2.65%; Italy-based utility cable provider Prysmian ( PRY) , down 1.86%; and utility network provider ESCO Technologies ( ESE), lower by 0.10%.