Environmental Leader

More details have come out about Duke Energy’s $100 million investment in commercial-scale rooftop solar panels, which we reported on last month. Duke plans to install approximately 20 megawatts of distributed solar generation at up to 850 sites in its North Carolina service area, including homes, schools, stores and factories.

If the program is approved by regulators, the $100-million plan would be complete in about two years, the company says. Duke says it plans to recover its $100 million investment through North Carolina’s new REPS cost recovery mechanism.

Once the conversion of the solar power from direct to alternating current is complete, Duke says its customers will benefit from more than 16 megawatts of power. Over the life of the program, the company estimates the average customer’s bill will increase no more than 25 cents a month.

Duke Energy said last month that it will purchase the entire electricity output of the nation’s largest photovoltaic solar farm — 16 MW. The third largest emitter of CO2 in the U.S., Duke Energy’s 2007/2008 sustainability report (PDF) outlines a scenario that would enable it to cut its 2006 CO2 emissions in half — by approximately 50 million tons — by 2030.

Cox Communications is testing a tradeoff in which customers allow the communications company to install solar panels on their roofs.

Xcel, and Southern California Edison that have also enlisted roofs for solar installations.