As Douglas County leaders are exploring options to save on energy costs, they are looking at the building that uses the most hot water — the Douglas County Jail.

County commissioners Wednesday will consider a proposal to place a thermal solar panel on the roof of the jail, 3601 E. 25th St., to harness energy and offset natural gas costs.

“Just as far as buildings go it was an attractive location because of the use and size,” said Gabriel Engeland, a Douglas County administrative intern.

Engeland estimates a 200-square-foot system would cost the county $10,000 after applicable tax rebates and eventually pay for itself. It would also be maintenance free, but the jail uses so much hot water, the solar thermal system would only account for part of its natural gas use.

The jail incurred in $99,200 natural gas costs in 2008, and Engeland projects a 200-square-foot solar thermal system would save an average of $1,230 a year and $18,750 in 15 years.

Engeland said recent incentives from the federal government have made looking at solar panels more attractive.

“It’s cost-effective right now, whereas a couple of years ago it wasn’t,” he said.

Commissioners would also have the option to install a smaller 100-square-foot system, he said.

The commission will meet at 4 p.m. at the Douglas County Courthouse, 1100 Mass.

They also have a session scheduled for 6:35 p.m. to consider approval of a cooperative agreement with the city to purchase the former Oread Labs building near Bob Billings Parkway and Wakarusa Drive.

The nearly 18,000-square-foot building would be leased out to bioscience companies — including CritiTech, a Lawrence-based pharmaceutical company looking for room to grow.