NRG Energy is one of the largest utilities in the US with around 22 GW of Installed Capacity.However like Exelon,the share of Renewables is relatively low at just 2% of its overall Energy Capacity.Though the US Administration has all but given up on an Energy and Climate Legislation,Big Utilities recognize the need to generate low carbon electricity.Some sort of Carbon Emissions Restraint will be imposed on Utilities sometime in the future with EPA itching for action in restricting CO2 Emissions.Green Sector Stocks have fallen like a rock in 2010 due to the Copenhagen Disaster and lack of movement on a Climate Bill by the US government.Therefore it makes sense for US utilities to buy Renewable Energy Assets on the Cheap.Exelon bought Deere Energy Wind Farms at a dirt cheap price.NRG Energy which has around 550 MW of Wind and Solar Capacity bought Reliant Energy last year for $300 mm.It has augmented its Renewable Energy Portfolio with another $350mm buy of Green Mountain Energy.