Floating Solar Makes Energy On The Water

Floating solar comes to Britain, offering the potential to convert water bodies into energy generators.
Published: Thu 10 Dec 2015

Various forms of marine energy, such as wave, tidal and current energy, have been under development for years, but less interest has been shown in inland water bodies such as lakes and reservoirs that don’t have an internal motion that can be exploited.

But that is now changing with new floating solar PV technology being pioneered by companies such as Ciel & Terre in France and Sunengy in Australia. This is opening the way for water body owners, whether private such as farmers or public such as municipalities, to exploit a new resource for power generation, especially in areas where land space is limited for such activities.  

To date the largest floating solar project is believed to be a 1.2MW plant that was commissioned in July 2013 on a reservoir in Okegawa City, Saitama Prefecture in Japan. However, interest and plans are growing for larger systems up to several tens of megawatts in countries including India, Brazil, Singapore and the USA.

Sheeplands Farm floating PV

Interest is growing in Britain too with the first floating PV installation now in operation on a 120ha soft fruit farm near Wargrave, Berkshire. The installation uses Ciel & Terre’s Hydrelio PV system and includes ABB’s TRIO three-phase string inverters and Aurora Vision monitoring system.

The installation of 800 panels covering about 0.4ha is aimed to deliver 200kW of energy. It is expected to pay for itself within six years and deliver profits of at least £620,000 over 20 years.

“To get the returns I expect, reliability is key,” says Mark Bennett, owner of Sheeplands Farm and CEO of Floating Solar UK. “The more downtime you have, the less efficient and less profitable it becomes.”

The Hydrelio technology comprises a series of high density polyethylene floats on to which the PV panels are attached, and which clip together to form a floating pontoon. Once assembled the pontoon is anchored in position with chains to avoid movement with wind or water level variations.

Floating solar in UK

Mr Bennett believes that there is considerable potential for floating solar in Britain. Through an agreement with Ciel & Terre he established Floating Solar UK to distribute its technology and together with ABB, the two companies are targeting “functional reservoirs”, i.e. those used for irrigation or drinking water.

“We see a good market in the UK for utilities and quarries with idle bodies of water to cut their energy costs through energy self-consumption facilitated by innovative floating solar projects,” observes Bradley Morgan, Technical Engineer with ABB’s solar business. “Some may even generate an additional revenue stream by selling unused power back to the grid.”

Floating solar projects in Britain

The second floating solar project in Britain has just been completed – a 55kW installation for a Norfolk landowner. The project was by local renewable company East Green Energy.

Britain is also in the race for what, for a time at least, will be the world’s largest project. A floating solar plant with 12,000 panels of 3MW capacity is being installed in Hyde in Greater Manchester on the town’s Godley reservoir for water utility United Utilities. The project, which is due to be completed before Christmas, is expected to supply 2.7GWh of energy annually.

Floating solar benefits

Given that no earnings from valuable land have to be sacrificed to make space for floating solar installations, the scope for such projects is expected to rise steadily throughout the next decade.

Installations at water utilities and quarries around the UK could be up to 100 times larger than Sheeplands Farm and still be profitable for companies, despite the government’s recent efforts to reign back renewable subsidies. [Engerati-Cutting the Renewables Subsidy Umbilical Cord]

Additional benefits include fast installation – the Sheeplands Farm project was completed within a week  – higher panel efficiency due to the cooling effect of the water, and reduced algal growth and evaporation from the water body itself.