Ohio’s Twin Lake Reservoir is no longer just a spot for fishers to cast for largemouth bass on summer evenings. The four-acre stretch of water in Lima now hosts more than 3,400 solar arrays, connected to floating docks by a team of 12 engineers and construction workers. Once complete, the floating photovoltaic farm will supply electricity to the adjacent water treatment plant — a facility whose pumps run 24 hours a day, 365 days a year.
Floating solar on Twin Lake Reservoir
“The water treatment plant is one of the city’s biggest energy costs; it only made sense to put the floating solar site here,” said Sara Weekley, deputy director of Lima’s utilities department. “It also helps keep water rates stable by lowering energy costs.” The project is expected to save the city and its taxpayers roughly $10 million over its lifetime, with an estimated $200,000 in savings during the first year alone.
The developer is D3Energy, a Florida-headquartered company that has built more floating solar arrays in the United States than any other firm, with more than 25 projects currently underway. D3Energy partners with French manufacturer Ciel & Terre, which holds the patents for the Hydrelio system — an industrialised, water-based photovoltaic technology. The Lima array will generate up to two megawatts of power, enough to run the treatment works.
Funding came partly from the federal government: $2.4 million in grant money from the U.S. Department of Energy and nearly $900,000 in tax credits through the Inflation Reduction Act’s direct pay programme, covering about half the total cost. The remainder was met by the city.
Beyond electricity generation, the floating panels deliver environmental benefits. By shading the water surface, they can reduce evaporation by up to 70 per cent and limit algae growth. “It keeps the water cooler; we’re not using any additional land,” Weekley noted. The water, in turn, provides a natural cooling effect on the panels, boosting their efficiency by between 5 and 15 per cent compared with ground-mounted systems.
In winter, when temperatures drop below freezing, water from neighbouring reservoirs is pumped into the lake to prevent ice forming, allowing the arrays to continue producing electricity without interruption.
How floating arrays stack up against land-based solar
Floating solar occupies a significantly smaller footprint than conventional ground-mounted installations. “A typical one megawatt floating solar system can fit on roughly two acres of water, compared to approximately five acres of land for a comparable ground-mounted system,” said Stetson Tchividjian, D3Energy’s managing director. This compactness matters acutely in the Midwest, where agricultural land is the backbone of the local economy. “You don’t want renewable energy and food production fighting each other for the same acres,” Tchividjian added. “Floating solar resolves that equation.”
There is a higher upfront cost: floating systems typically run 10 to 25 per cent more expensive than land-based equivalents because of specialised floating platforms, marine-grade anchoring and waterproof components. But those costs can be recouped over a project’s lifespan through avoided land acquisition, higher energy yields and water conservation benefits. D3Energy’s track record suggests the technology is already proving itself at scale. Ninety miles north-west of Lima, the company has just finished a floating solar installation three times larger — a six-megawatt project in Monroeville, Ohio, which is due to become operational in early 2026. The Monroeville array is owned and operated by Gardner Capital, with local contractor ARP Solar involved in construction.
D3Energy also completed Ohio’s first floating photovoltaic array for Del-Co Water, which began operation in 2024, and the company’s installations in Florida weathered Hurricane Milton in 2024 with no damage — unlike many ground-mounted and rooftop systems — demonstrating the resilience of the technology. Modern panels are engineered to withstand winds of up to 180 miles per hour, and tracking systems can be placed in a “stow” mode that tilts panels to steep angles, reducing hail and wind damage.
A regional shift to clean energy
The Lima project is part of a broader evolution in the industrial Midwest from heavy manufacturing to clean energy. Electricity has become one of the region’s most important commodities, with utility rates rising sharply in recent years because of demand from data centres, higher transmission charges and the war in Iran, which pushed local petrol prices to $5 a gallon. Consumers have been searching for alternatives, and while floating solar is only available to those with access to waterways, states such as Michigan and Minnesota boast some of the highest numbers of lakes in the country — not counting the Great Lakes system that borders Ohio and seven other states.
According to the Solar Energy Industries Association, the midwestern states of Illinois, Indiana and Ohio now rank 10th, 11th and 12th nationally for solar capacity. Michigan, in particular, is poised for strong growth, with more than 3,600 new megawatts planned by 2028 — the largest pipeline in the Midwest Independent System Operator region. Despite a reputation for persistent cloud, Ohio receives more sun than Oregon and almost as much as Alabama, according to the Centers for Disease Control and Prevention, making the region viable for solar generation.
An hour’s drive north of Lima, in Perrysburg, Ohio, First Solar has become one of the largest solar module manufacturers in the western hemisphere. Two years ago it opened the country’s biggest solar research and development facility, where it has spent $2.4 billion manufacturing perovskite semiconductor-built solar technology expected to usher in higher-efficiency applications. The war in Iran — which has blocked about 20 per cent of the world’s oil consumption through the Strait of Hormuz — has underscored the value of domestic energy generation. “Domestic generation that isn’t exposed to a single geopolitical event is more valuable, not less, in this kind of environment,” Tchividjian said. “Solar is a key cog in that wheel.”
Challenges and trade-offs
Despite the momentum, solar energy faces deep-seated resistance in rural America. The idea of covering land that has fed millions with glass and metal does not sit easily with everyone. Fossil fuel companies have spent millions of dollars on scare and disinformation campaigns, which have led city and county authorities across the region to ban large-scale solar farms on agricultural land. In Ohio, a 2021 law added further hurdles by allowing counties to block wind and solar projects before they reach the state siting board.
For landowners and farmers, solar leases have become a route to guaranteed income at a time when the Trump administration’s tariffs are destroying demand for U.S. agricultural products such as soybeans in China. Farmers across the eastern corn belt are struggling to make a profit from growing crops. Yet some rural residents oppose solar because of what they see as its role in inflating agricultural land prices, making it harder for crop growers to access land.
Doug Goyings and his family, who farm about 5,000 acres of barley, soybeans and corn in Paulding county — an hour’s drive north-west of Lima — have direct experience of the downsides. Their two-acre solar array, producing 130 kilowatts, has eliminated their electricity generation bill, but not their transmission and distribution charges. “I don’t have to pay an electric bill at all, on the generation side,” Goyings said. “But the transmission and distribution [charges], it’s outrageous. They’re saving us all this money, but the electric company is not going to take a loss. They got these fees that they put on there.” In March, he produced 2,160 kilowatt-hours of surplus power that went back to American Electric Power’s grid. The resulting transmission and distribution fees came to $918. “I used no electricity from them,” he said.
American Electric Power, the major utility in the region, generated about 3.5 times as much electricity from coal and natural gas as from renewables in 2024, according to company figures.
In March, a tornado 180 miles west in neighbouring Indiana tore through one of the largest solar arrays east of the Mississippi River, causing damage that could cost hundreds of millions of dollars to repair. The incident illustrated, for some observers, the inherent vulnerability of the technology. But Jeff Risley, executive director of Renewable Energy Farmers of America, a farmer-led non-profit trade association, dismissed the idea that localised weather events point to systemic fragility. “The industry has developed technology specifically to protect against severe weather,” he said. “They now have tracking systems with ‘stow’ modes that position panels at steep angles to reduce hail and wind damage.”
Risley argued that the opposition to solar is often about more than the hardware. “The tension around solar is often less about the technology and more about change to communities. Many landowners feel caught in the middle: developers want their signature; neighbours may be hostile and there is limited independent guidance to help them evaluate whether a project makes sense for their situation.” REFA was formed to provide exactly that sort of unbiased resource for farmers navigating solar leases and development.
In Lima — a city better known for refining oil and building military tanks — the floating solar project on a reservoir that supplies thousands of residents with drinking water represents a major shift. When it is finished this summer, it is expected to save the city $10 million over its lifetime while cutting evaporation and algae growth. “People like the idea that it’s not taking up any land and of us trying to save money,” Weekley said.
