Wave power has yet to be as successful as solar or wind power, even though the potential energy that could be harvested is huge. Mike wrote about the things that hold it back, one of which is that the sea can be really hard on the equipment built to harvest the wave energy. Wave power buoys and other designs have all had a mix of success and failure thanks to the rough and corrosive nature of the ocean.
For investors that are looking for a safe venture, wave power can be too risky.
A new project in Norway by Kvernevik Engineering AS is side stepping that issue by converting old boats and other water vessels into wave power machines. The vessels were built to withstand the rigors of the ocean and now they'll have a new life creating clean energy instead of ending up in the junkyard.
The project has converted one old fishing trawler so far using based on an idea that Geir Arne Solheim, the founder of Havkraft AS, came up with. The vessel uses a "fluctuating water column" system to generate electricity from the waves. The boat has four chambers installed in its bow that the ocean water flows in and out of. When waves hit the boat, the water flows into the chambers, which increases the air pressure at the top. That pressure drives the turbines located at the top.
The reverse flow of the water back out causes the air to be sucked back down, which turns the turbine again. The bobbing action of the boat in the waves adds to the power being generated. The boat is safely anchored facing into the waves for maximum power output.
“All we have to do is to let the vessel swing at anchor in a part of the ocean with sufficient wave energy. Everything is designed to be remotely-controlled from onshore”, said Project Manager Edgar Kvernevik.
Computer models estimate that the vessel can produce 320,000 kWh per year. Kvernevik plans to build a hydrogen production plant onboard the trawler to store the energy that is being produced so that it could be used in hydrogen fuel cell cars.
The project is hoping to build similar systems on either a larger ship or a barge and they'd also like to retrofit a semi-submersible craft with a 4MW wave power plant coupled with wind power production above the water.