Renewable energy dilemma: Ocean could be the solution

Las Vegas: A wind turbine sitting idle on a calm day or spinning swiftly when power demand is already met poses a problem for renewables and is one researchers think can be tackled under the sea.

In one vision, offshore wind farms could use seawater to essentially store energy until it’s needed, helping wean humanity off fossil fuels.

“We came up with a solution that we call the ocean battery,” Frits Bliek, CEO of Dutch startup Ocean Grazer told Agence France-Presse (AFP) while showing off the system at the CES tech fair in Las Vegas.

Amid the growing push away from climate-warming energy sources like coal, stockpiling green energy is key, experts say.

That’s because nature does not always deliver wind – or sun – at the moment when electricity is most in demand.

Bliek’s “ocean battery” relies on massive flexible bladders on the seabed, which are filled up with seawater by the wind farm.

When the power is needed, the pressure of the ocean squeezes the water through the system on the seafloor that includes turbines – and the result is electricity.

A key consideration with energy is cost, and storage systems involving some type of battery are not only very expensive but also at risk of leaks or contamination in an ocean environment.

Systems that rely on pressure are already used in hydroelectric dams that pump water into the reservoir behind the dam when the electricity demand falls, effectively storing it to come back through the facility’s turbines.

The U.S. Department of Energy traces the concept, called “pumped storage hydropower,” to Italy and Switzerland in the 1890s, though facilities can now be found all around the world.

As for the underwater version of this type of storage, Ocean Grazer is not alone in trying to make it work. -Agencies