What has been described as the first US solar district heating system, supported with US$1 million in American Recovery and Reinvestment Act funding under the Department of Energy's
Solar America Communities programmme
, has been launched.
District Energy St Paul provided matching funds and now operates the system, which heats water using 144 solar collectors located on top of St Paul, Minnesota's downtown city convention centre.
The water heats the convention centre and neighbouring buildings in North America's largest hot water district heating system, which covers 80% of downtown St Paul.
The rooftop project is designed to peak at 1 MW thermal capacity.
While it will primary supply the city's downtown Saint Paul RiverCenter convention centre with hot water and space heating, any excess solar-heated water will travel to the district's other customers.