UK company ShipEco Marine Limited says old oil tankers can be repurposed to generate energy, amongst other renewable energy, natural gas and desalination solutions.
According to the company, around a hundred oil tankers are retired each year, and in most cases, they find a new home on the shores of Bangladesh, where they feed the parts salvage industry and scrap market.
The repurposed oil tankers would have circular holes cut into the bottom of the hull, and a watertight silo created within each.
Energy is generated by air pressure, generated by the motion created by waves and the current inside each of these silos. The increased air pressure would drive a turbine mounted horizontally on the top of each shaft, to run a generator and produce energy.
According to the company, laboratory tests have shown the concept to be feasible, and may even be more effective that other marine energy technologies as the ships could be based further out to sea, where wind speeds and wave conditions are significantly stronger.
“It works like a giant piston,” says Florent Trarieux, a renewable energy engineer who tested the concept in scale models at Cranfield University. “We would put a turbine at the top of the chamber that is driven by the air as it is pulled back and forth by the water. We could put these in columns all down the length of a ship like an oil tanker.”
ShipEco Marine also suggest that technologies such as waste-to-fuel, alongside the “EnviroShips” can be used in water desalination, renewable natural gas, hydrogen and nitrogen production, and even offset energy demand generated by data centres.
Andrew J. Deaner, developer of the original design said: “WaveShips will use the world’s natural ocean energy to create major public utilities in a clean efficient way, for everyone to live, in a sustainable world for ALL future generations – true global sustainability.”
Here's the company’s YouTube video on the concept: