Will Wave Power Ever Make a Big Splash?

Wind and solar tend to capture most of the attention in renewable energy, but what about waves? They’re predictable, accessible, and loaded with energy, and because the machinery is mostly below the surface nobody can complain about the aesthetics. Also, the majority of human population lives near a coast, so power wouldn’t have to be transmitted long distances. It seems too easy, and yet wave energy remains a small player in the industry.

Well, there are several reasons that wave power hasn’t made a big splash, not the least of which is that salt water is a pretty harsh environment. But another reason is that there’s no “tried and true” design for a generator that converts wave power into electricity. Many competing designs exist, but nothing has emerged as the industry standard like the horizontal axis turbine is to wind power. A group of wave energy developers is attempting to remedy that situation by forming a consortium and consolidating their efforts to create a standard type of wave energy converter.

Two Methods

Existing wave power generators have many distinct ways of harnessing that motion. From there, you have two options: convert it to electricity underwater and run wiring to the shore, or use hydraulic pumps to send pressurized water to the shore where it can then be converted to electricity. OPT’s PowerBuoy is an example of the former; it produces electricity only.

Image courtesy of Ocean Power Technologies


On the other hand, pumping water to shore, as done by Carnegie Wave’s CETO, allows the system to not only generate electricity, but to also desalinate salt water.

Image courtesy of Carnegie Wave Energy

What I like about the CETO design, besides the fact that it desalinates water as well, is that it uses standard generators; a new design for underwater generators isn’t needed.


WavePOD: A Standard Generator Design

It appears as though the consortium, which includes Carnegie Wave Energy, is ignoring my opinion and designing an off-shore generator that sends electricity, not pressurized water, to the shore. (Who am I to argue with the experts?)  The WavePOD (Wave Power Offtake Device) will sit on the seafloor, converting linear wave motion into rotational motion, which is then converted to electricity.

Image courtesy of Aquamarine Power


Competition drives innovation, but there’s also a time when consolidation of effort is appropriate. Although these companies are working on a common design for the generator, the remaining components of the system can still be unique to each manufacturer. According to Aquamarine Power's Chief Executive Officer Martin McAdam, "The global wave energy market has an estimated value worth hundreds of billions of pounds and the WavePOD addresses the sector's challenges of improving reliability, developing standard components, fostering collaboration and driving down costs." This consortium may be the boost that wave power needs to become a bigger player in the renewable energy industry.

There’s an old saying: “You can’t stop the waves, but you can learn to surf.” Maybe someday they’ll say, “You can’t stop the waves, but you can turn them into electricity.”