Floating Solar Panels: World’s Largest Installation to Set Sail This Year

The Netherlands is set to play host to the world’s largest collection of solar panel islands, capable of withstanding high wind speeds and repositioning itself to track the sun in the sky. The installation will cover around half the surface area of North Holland’s Andijk reservoir, used by water firm PWN to purify and supply 25 million cubic meters of drinking water.

“There is a lot of pressure from pressure environmental groups about wind turbines, so the alternative to land is water. But what does it do to the water quality?” Arnoud van Druten, managing director of Floating Solar, told The Guardian in a Sunday story. “Our design has the least impact on the ecosystem as possible so the water quality remains almost the same. At the same time, because the island is moving, we don’t have a fixed shadow shape.”

Floating photovoltaic panels — dubbed “floatovoltaics” by some — could offer a promising solution for helping to transition the world onto sustainable energy. The technology has boomed from the first demonstration 10 years ago in California, reaching over 100 sites at the end of 2017.

The Netherlands project is set to cover 15 islands with a total of 73,500 panels. The initial phase, covering three islands measuring around 460 feet in diameter each, is set to hit the water in November. While the company could have moved faster, it needed to ensure the birds had finished their migration season, giving them a three-month window to deploy the islands. The project will combine with another site involving static panels in nearby Hoofddorp to provide energy for 10,000 homes.

The panels use a sun-tracking algorithm to boost efficiency. Three buoys automatically turn to the light, using a computer-powered algorithm to gradually adjust the position. The developers argue that the position of the sun changes little over the course of a year, making it ripe for automation.

The system also moves in the case of severe weather, ensuring the waves can glide smoothly through the islands. Even without these changes, the islands can still withstand wind speeds of up to 60 mph. While it seems like it could pose more challenges versus a land-based installation, Van Druten claims the water has the advantage of cooling the cables during use.

If successful, it could help inspire similar projects. The National Renewable Energy Laboratory claims they could supply 10 percent of the United States’ energy, saving 2.1 million hectares of land. The team describes this as a “very conservative” estimate. Despite these figures, there are only seven such projects in the United States. Other countries have shown more interest, with Japan already hosting 56 of the 70 biggest installations and Thailand planning a combined 2.7 gigawatts of floating solar by 2037.

Similar projects could benefit the local ecosystem, reducing water evaporation and encouraging algae growth. These environmental benefits have been found in land-based facilities, like India’s Cochin International Airport which used the land underneath panels to grow 60 tons of vegetables in one year. Germany’s University of Hohenheim found that such “agrophotovoltaics” can boost land use efficiency by 60 percent.

The open ocean could prove a great resource for keeping global temperatures two degrees below pre-industrial levels. Carnegie Mellon University found in 2017 that open ocean wind farms could meet current global energy demand thanks to high speeds. In 2018, offshore wind grew by a staggering 20 percent. Beyond wind and solar, the United Nations is exploring an idea to build self-sustaining cities at sea, starting from scratch and possibly offering lessons for land-based living.

With 2018 the fourth-hottest year on record, these sort of ideas may be necessary now more than ever.