“Float-ovoltaics”: How solar panels suspended in reservoirs could transform the world’s energy supply

They have been attached to farms, garbage dumps, and parking lots through creative schemes. Researchers are now pleading with governments to fund floating solar projects.

The 115,000 reservoirs in the world could produce 9,434 terawatt hours of power annually if 30% of their surface were covered with solar panels, according to research published in the journal Nature.

That is more than three times the EU’s energy output, which in 2021 totalled 2,785.44 terawatt hours.

How do they work?

Countries must invest in renewable energy if they want to achieve net zero.

A 2021 study found that for nations to completely decarbonize, solar panels might need to occupy between 0.5 and 5% of their land area. Solar energy may be significantly more environmentally friendly than natural gas, but it requires about 70 times more land per energy unit.

Planning professionals may clash with farmers, local authorities, and conservationists when space is at a premium. A solution might come from floating solar.

They produce electricity from sunlight just like regular ‘photovoltaic’ cells. The only distinction is that they are called “floatovoltaics” because they float on pontoons.

An irrigation canal, quarry lake, or reservoir are the ideal locations for solar because they have stable, unobscured water surfaces.

In 2008, the first floatovoltaic system was put in place. The largest installation in the world, the Dezhou Dingzhuang Floating Solar Farm in China spans nearly 600 hectares.

What potential does floating solar have?

A study published in Nature claims that floating solar installations, which currently make up less than 1% of all solar installations worldwide, have “huge potential there.”

The authors claim that local FPV (floating photovoltaic) plants could make 6,256 communities and/or cities in 124 countries, including 154 major cities, self-sufficient. This is so that specialised local power systems could potentially be developed, as most reservoirs are situated close to significant population centres.

Additionally, floating solar could prevent water evaporation from deteriorating. According to the study, installing this many solar panels would save 300 million people’s worth of water each year.

What are Solar’s advantages for the environment?

Keeping fossil fuels underground becomes more crucial as the world warms.

We still have 380 billion tonnes of CO2 in the global carbon budget, according to the Global Carbon Project.

This is the maximum amount of CO2 we can emit while still having a 50% chance of limiting global warming to 1.5 degrees Celsius.

Carbon emissions reached an all-time high of 36.8 billion tonnes in 2022. But it’s not all terrible news. Countries are also substantially investing in renewables. In 2022, wind and solar produced one-fifth of the EU’s electricity, the first time that clean energy sources produced more electricity than fossil fuels.