US Goes Bonkers Over Floating Solar Power Plants

First it was a trickle, now it’s a flood. US energy planners are finally catching up with the floating solar trend, in which solar panels rest on the waters of lakes, reservoirs, and other bodies of water. Among other benefits, the technology could provide solar developers with another pathway for introducing more solar energy into rural areas, without impinging on farmland or disrupting native habitats.

Floating Solar To The Rescue

The allure of a large, flat, shade-free, unoccupied space is a tempting one for solar developers. Bodies of water can offer that, though there are challenges. Unlike a typical ground-mounted array, waterborne arrays need to be moored to something, and the moorings need to take any changes in the water level into account. Depending on the location, developers also have to account for ice, snow, choppy water, and other harsh conditions, along with the potential for corrosion, complications involving repair and maintenance, and issues involving shoreline access.

Apparently engineers have met those challenges, because the global floating solar industry is already off to the races. Last year, for example, the International Energy Agency took note of Indonesia, where West Java is hosting a new 145 megawatt floating solar power plant, with plans for another 60 floating arrays in the works.

Last year the online journal iScience posted a state-of-affairs rundown of the global floating solar industry, in which the authors listed several key benefits.

Floating arrays “do not occupy habitable and productive areas and can be deployed in degraded environments and reduce land-use conflicts,” the authors explained.

“Saving water through mitigating evaporation and improving water security in arid regions combined with the flexibility for deployment on different water bodies including drinking water reservoirs are other advantages,” they added.

The authors also highlighted the use of solar panels on existing hydropower reservoirs, which could help alleviate the need to build new hydropower dams in the future (see the CleanTechnica take here).

Floating Solar For The USA

The National Renewable Energy Laboratory has been trying to get floatable solar arrays off ground here in the US for years, to no avail. A winery in California installed the world’s first floating PV panels back in 2008, but nobody else was inclined to make an attempt at any significant scale until 2016, when the Township of Sayreville, New Jersey, laid plans to install a floating solar array on a retention pond at its water treatment plant.

The Sayreville system went online in 2019, billed as the largest solar array of its kind in North America at 4.4 megawatts in capacity.

This time around, the spark caught fire. In 2020, the US Department of Defense let slip a plan for putting solar panels on Big Muddy Lake at Fort Bragg in North Carolina. The installation was completed last year.

Also in 2020, the town of Cohoes in upstate New York unveiled plans for a solar installation at the municipal water supply. As the first publicly owned, utility scale floating solar power plant, the array could serve as a model for financing and building floating arrays for other public water systems.

Another First For Floating Solar In New Jersey

The Cohoes project is weaving through the review process and it appears to be closing in on the finish line. Meanwhile, the energy firm New Jersey Resources was not to be caught napping. Though better known as the parent company of New Jersey Gas, NJR is also transitioning into renewables through its NJR Clean Energy Ventures subsidiary, which spotted another floating solar opportunity in New Jersey. In May of 2022, the company began construction on a floating array at a water supply reservoir owned by the New Jersey American Water company in Short Hills.

NJR Ventures and its partners announced completion of the array last week, upstaging Sayreville with a capacity of 8.9 megawatts.

“The clean power generated is enough to power 1,400 homes annually and will provide approximately 95% of the power needs for New Jersey American Water’s Canoe Brook Water Treatment Plant,” NJR Ventures explained in a press release. They also anticipate that the 16,510 solar panels in the array will help conserve water by reducing evaporation.

Everybody Into The Pool

Activity east of the Mississippi is also starting to bubble up. In 2021, the Township of Plainfield, Michigan, reached an agreement with solar installer White Pines Renewables to install a floating solar array on its water treatment plant. At the time, the township anticipated saving up to $2 million in electricity costs over the life of the array.

“The Water Plant is the highest electricity user of all Township buildings,” Township officials noted in a press release. “Once fully operational, nearly 37% of the Water Plant’s electricity is projected to come from the solar panel system.”

While that project is working through the approval process, a ringing endorsement of the reservoir-to-solar trend has come from US Representatives Paul D. Tonko (D-NY) and Jared Huffman (D-CA), along with US Senator Angus King (I-ME). Last year the three legislators introduced a bill in support of a national floating solar policy called the POWER our Reservoirs Act, short for Protect our Waters and Expand Renewables on our Reservoirs Act.

“Floating solar offers tremendous opportunities to build a more sustainable clean energy future and protect our threatened water systems, including by reducing evaporation and preventing harmful algal blooms,” said Representative Tonko in a press statement earlier this year.

One aim of the POWER Act has already become law, with the authorization of $10 million for a US Army Corps of Engineers study of the potential for floating solar to alleviate drought as well as supply clean energy.

The other provisions add more muscle to the study of floating solar. The Act would also fund pilot programs at both the Army Corps of Engineers and the Bureau of Reclamation.

Socialism!

The Bureau of Reclamation is a public water supply agency that does not often grab the media spotlight, but it soon may start attracting more interest.

“Established in 1902, the Bureau of Reclamation is best known for the dams, powerplants, and canals it constructed in the 17 western states,” the agency explains. “These water projects led to homesteading and promoted the economic development of the West. Reclamation has constructed more than 600 dams and reservoirs including Hoover Dam on the Colorado River and Grand Coulee on the Columbia River.”

“Today, we are the largest wholesaler of water in the country. We bring water to more than 31 million people, and provide one out of five Western farmers (140,000) with irrigation water for 10 million acres of farmland that produce 60% of the nation’s vegetables and 25% of its fruits and nuts.” they add.

If that’s beginning to sound familiar, you may be thinking of the nation’s sprawling system of member-owned rural electric cooperatives. The REC system is a Depression-era program aimed at filling huge gaps in rural electricity access when private sector developers dropped the ball. REC’s exist to benefit their ratepayers and communities, not to profit investors.

RECs have been deploying their public benefit mission to push the rural solar envelope, including support for the emerging agrivoltaic industry. If all goes according to plan, the floating solar trend will hit high gear with the one-two punch of RECs and the 600 reservoirs of the Bureau of Reclamation.

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Photo: Solar array on a reservoir in Millburn, New Jersey courtesy of businesswire.com.