Northwest Ohio community saves land space by siting solar project on reservoir

Lima, Ohio just finished building a 2-megawatt solar array that floats on the Twin Lake Reservoir, the city's main source of drinking water. Instead of putting solar panels on land, the project uses over 3,100 panels mounted on floating systems anchored to the reservoir's banks and bottom, with power sent to inverters on shore. Rising or falling water levels don't affect the system, since the mooring lines adjust automatically. The setup takes up just four acres of water, compared to the 10 or more acres a similarly sized project would need on land.

The solar power will help run the water treatment plant next door, which processes 14 million gallons of water a day and is the city's biggest energy user. Officials expect the array to save $10 million in electricity costs over its lifetime. The $5 million project got $2.4 million in federal grants from the U.S. Department of Energy and will also use close to $1 million in direct-pay tax credits, a way governments and nonprofits can get cash back for clean energy projects instead of a tax deduction.

This isn't a story about upgrades homeowners can make themselves, but it points to a broader trend: communities finding creative places to put solar panels, including reservoirs and water bodies they already own, without using up farmland or open space. It's the third floating solar project built in Ohio by the same companies, with another larger one set to come online later this year.