COLUMBUS — The Sierra Club is urging Duke Energy Ohio to put more effort into energy efficiency and developing wind and solar power facilities, rather than build a nuclear power plant in southern Ohio.

A Public Utilities Commission of Ohio attorney-examiner heard testimony Monday about Duke Energy’s long-term energy forecast plan, a required filing for Ohio utilities to predict future energy demands and suggest how the companies will meet those needs.

Duke said in June that it had joined an alliance “to explore potential nuclear options in Ohio” and is doing studies to assess whether Piketon, in Pike County, would be a suitable site for a nuclear generating plant. The assessment is still being done and no decision has been made, company spokeswoman Sally Thelen said Tuesday.

Energy efficiency programs would be cheaper than building and operating a nuclear plant, said Jen Miller, of the Sierra Club’s Ohio chapter.

“We absolutely support energy efficiency, and work very hard at finding new opportunities for our customers to save money,” Duke’s Thelen said.

Some who testified at the PUCO hearing urged the agency to schedule at least one hearing in the Cincinnati area, the heart of Duke’s Ohio service territory, to hear testimony on whether the company should be allowed to build a nuclear power plant in Ohio.

If Duke decides to build an Ohio nuclear plant, there will be opportunities for public comment and meetings during that process, Thelen said.