Lake County Lands 252 kWh Floating Solar Array

Consisting of 720 panels, the Kelseyville facility floats on a man-made wastewater treatment pond. This is California's first public solar power system.

By Anca Gagiuc


Ciel & Terre USA has completed a 252 kWh floating photovoltaic power system for the Lake County Special Districts on behalf of Kelseyville County Waterworks District #3. The project has been coordinated in collaboration with local contractor North Coast Solar and is part of four projects in the U.S. totaling 5.4 megawatts. 

The Ciel & Terre Hydrelio facility, the first public solar power system installed in California, has been financed by a municipal lease. This gives the county positive cash flow starting the first year, so no cash investment was required to pay for the system. Once the Kelseyville solar installation proves successful, the Lake County Special District takes into account installing additional floating solar power systems around the county.

No real estate required

The system, which consists of 720 floating solar panels mounted together, floats on a man-made wastewater treatment pond in Kelseyville and is expected to produce up to 1,650 kWh in its first year. To safely deliver the electrical power it produces and to maximize inverter output, it uses solar optimizers provided by SolarEdge.

“We didn’t have available land or rooftop space suitable for this project, but our wastewater treatment pond had enough surface area to accommodate a sizable solar system. Floating is a great way to control algae growth in the pond at the same time we generate virtually free energy. All costs to provide utilities continue to increase, which forces Special Districts to seek out and implement any means possible to reduce future costs. This floating solar system will result in significant savings in future years,” Jan Coppinger, special districts administrator for Lake County, said in a prepared statement.

Floating solar systems are seen as a solution for any utility district as it couples clean energy generation with water conservation benefits. Floating a solar array on man-made bodies of water improves energy production by keeping the solar system cooler, while reducing evaporation. In addition, it controls algae growth and reduces water movement to minimize bank erosion. It also makes optimal use of pond surfaces, providing energy without involving real estate or requiring rooftop installations.

“Municipal water districts, wineries, farms, and others want to adopt solar but they don’t want to commit land that could be used for other purposes,” added Eva Pauly-Bowles, representative director for Ciel & Terre USA. “Installing floating solar systems gives them ready access to green energy while helping them manage their water resources. We expect we will see more demand for floating solar systems, especially in light of California’s commitment to produce only carbon-free electricity by 2045.”

Video courtesy of Ciel & Terre International