A wind turbine sitting idle on a calm day and spinning swiftly when power demand has a problem for renewables. Scientists think this problem can be sorted under the sea. Offshore wind farms can use seawater to essentially store energy. This helps us in fossil fuels.
As climate-warming energy sources like coal is reducing, stockpiling green energy is becoming important.
Nature will always deliver us with wind and sun when we will need energy most.
Scientists made “ocean battery” which relies on massive flexible bladders on the seabed. These batteries are filled up with seawater by the wind farm.
When we need power, the pressure of the ocean squeezes the water through the system on the seafloor. This also includes turbines and electricity comes out.
But this comes costly. The storage system of the energy includes some type of battery that are expensive and have the risks of leaks or contamination in an ocean environment.
Systems that use pressure are already used in hydroelectric dams. This system pump water into the reservoir behind the dam. This happens when electricity demand falls.
The US Department of Energy called this concept “pumped storage hydropower”. This system was first developed in Italy and Switzerland in the 1890s. This system is now found all around the world.
For the underwater version of this system, scientists are trying to make it work.
Get rid of fossil fuels
University of Malta have developed a system that uses renewably made electricity to pump water into a chamber. This chamber contains under-pressure air. Then it turns a hydraulic turbine to generate power.
Another system named StEnSea (Stored energy in the sea) have hollow concrete spheres under the pressure of the deep ocean. This system was tested in Germany in 2016.
Undersea systems have advantage of the pressure below the ocean that is free. This can create a system that is about 80 percent efficient in storing energy.
Scientists think storage systems is a key for renewables. This has developed as the price to produce such energy has dropped. This has also made it a steadily growing part of the energy mix worldwide.
In the United States, renewables are the fastest-growing source. It has increased by 42 percent from 2010 to 2020.
But for “ocean battery” to work as part of an electricity grid still needs time. Scientists aim to have an offshore system in place by 2025. But by 2023, one will be deployed onshore in the northern Netherlands.