The District of Columbia has signed a 20-year power purchase agreement (PPA) with Iberdrola Renewables' 46 MW South Chestnut wind farm, located in Pennsylvania.
Under the PPA, the Department of General Services (DGS), which manages the D.C.'s portfolio of government buildings, will purchase the entire output of the wind farm. This will annually supply Washington with approximately 125,000 MW hours of electricity.
According to the release, the PPA is the largest wind power deal of its kind ever entered by a U.S. city and is projected to save local taxpayers $45 million over the next 20 years.
‘Directly sourcing renewable power costs 30 percent less than fossil fuel-based sources, reduces greenhouse-gas emissions by 100,000 tons and protects our city from volatile energy price increases,’ explains Mark Chambers, sustainability and energy management director at DGS. ‘Put another way, over its 20-year span, this deal removes the same amount of carbon from our atmosphere as planting 44 million trees or removing 18,000 cars from the road every year.’
Since 2012, the D.C. government has purchased 100% green power via renewable energy certificates (RECs). Under the new wind PPA, however, D.C. will directly receive wind power for 35% of its electricity demand.
Nonetheless, the D.C. government will continue to use RECs for the remainder of its electricity needs, ensuring that 100% of the city's electricity consumption remains emission-free.