Duke Halves Its US $100M Solar Energy Plan

Duke's revised proposal calls for US $50 million in spending over two years to generate 8 MW from up to 425 solar sites. Consumer advocates for the state Utilities Commission called the proposal too aggressive and expensive, the newspaper reported.

Under a 2007 state law, Duke has to use renewable energy sources to generate 12.5 percent of its retail sales by 2021. Solar power has to be a small but growing part of that mix, beginning in 2010.

Under Duke's original proposal, the utility would generate 16 MW of electricity by installing solar-photovoltaic panels on up to 850 roof and ground sites, most of them at commercial or institutional buildings. The power would feed into the larger power grid.

The Utilities Commission staff objected, saying that Duke doesn't need the full rooftop plan to meet its solar-power obligations through 2014. Duke has already contracted to buy 16 MW from a SunEdison solar farm to be built in Davidson County.

The size of the original proposal could also have handicapped development of cheaper forms of renewable energy, the staff said. Duke could "bank" excess solar credits for future years, it said, but miss the chance to generate power more cheaply if solar costs come down as expected.

According to the newspaper, under a 2007 state law, Duke has to use renewable energy sources to generate 12.5 percent of its retail sales by 2021. Solar power has to be a small but growing part of that mix, beginning in 2010.

Under Duke's original proposal, the utility would generate 16 megawatts of electricity by installing solar photovoltaic panels on up to 850 roof and ground sites, most of them at commercial or institutional buildings. The power, enough to supply about 2,600 homes, would feed into the larger power grid.

The Utilities Commission's Public Staff, which represents consumers, objected, the Charlotte newspaper reported.

Duke doesn't need the full rooftop plan to meet its solar-power obligations through 2014, the staff said. Duke has already contracted to buy 16 MW from a SunEdison solar farm to be built in Davidson County.

The size of the original proposal could also have handicapped development of cheaper forms of renewable energy, the staff said.

Duke could "bank" excess solar credits for future years, it said, but miss the chance to generate power more cheaply if solar costs come down as expected.

Industrial electricity customers, and retailer Wal-Mart and grocery chain Kroger, also objected to Duke's plan, saying it would raise their electric rates.

Solar advocacy groups complained that it left out non-utility solar power producers, although Duke says it has asked for proposals from solar producers.

This story was originally reported in Power Engineering International and was reprinted with permission.