Surfer's Aren't the Only Thing Riding the Waves: Ocean Absorber Buoys
Marine Energy: It's Closer Than You Think
And it's taking the world by STORM! Really, it seems as if new marine energy ideas are popping up like oysters on a rock. These concepts are especially flourishing in this enlightened age of green and sustainable energy innovation, making their mark as a moderate to top candidate in the running for replacing fossil fuels (at least in some major communities).
There is no disputing already that some of the vast examples of marine energy could replace the power supply needs of the world's coastal communities, but what exactly are these energy saviors and how do they work? Well, they mostly all share the same or similar principles, but they certainly don't replace each other - and some are much better than others.
In this article, we will focus on the one that we believe has strong, strong potential: the Point Absorber Buoy.
What Is It and How Does It Work!?
So, we all know what buoys are. Yeah, like that image above - they are colorful, they float, and they can tell sailors a plethora about where it is they are sailing and where they should avoid. Chances are, if you've been to the beach you've seen these things bobbing like your head while listening to some cloud rap music. How do these buoys compare to the Point Absorber Buoys?
Well, they got the floatation part in common, so there's that. I guess that's enough for them to know each other on a first-name basis... you know, if buoys could talk and network. But aside from that, point absorbers serve a different purpose than those that mark lobster pots, places you shouldn't sail, and buried treasure.
They generate energy!
Typically, the buoy captures the natural energy from the ocean by riding the heave of the wave; or, the amplitude of the wave, representing the increase the wave makes from the nominal ocean surface. As the buoy rides the heave, the tie cable keeps it locked in place so that the climb it makes drives the internal mechanics of a generator attached in series with the buoy's tie cable. Energy is generated in multiple different ways; in some cases, the generator is simply being powered by the motion of the waves using ratcheting mechanics internal to the generator. In other cases, the heave of the wave allows the buoy to rise, compressing some pressurized fluid in a column within the generator which is then forced through a turbine used to generate energy. Both methods are extremely similar in activity.
Pretty nifty invention, right? The concept is simple, yet it opens a vast world of possibilities for power supply to coastal communities, and possibly more. Note that in this example image, the buoy is anchored to a platform on the sea floor; in some models, the buoy does not need to be anchored - instead, they use a heavy weight to keep the buoy in tension while still allowed to ride waves. The benefit to that design would be the reduction in underwater work; you could just toss the buoy system into the water, connect to a mooring line at the bottom, hook up to a shoreside powerbank, and start powering all the important things lie your WiFi, Playstation 5, sodastream etc., you get the idea.
This is certainly one of my favorite methods for harvesting energy from the ocean; it's fairly efficient in comparison to other marine energy sources and it's a design concept that makes me feel enthusiastic about future innovations - 'cause that's what we are all about here, after all.
A marine energy farm in Reedsport, Oregon, also known as the Reedsport Wave Power Station was considered the first wave energy farm of it's kind - it moderated 10 buoys capable of providing 140-160kW each. It's output was measured to be 1.5MW, which is pretty good for renewable energy installations.
The PowerBuoy from Ocean Power Technologies (OPT) is one of the more notable and developmental Point Absorber Buoy projects in the current industry, though they have more than just the one type. The video above (created by OPT) does an excellent job of summarizing the deployment and operation of a modern Point Absorber Buoy. The video showcases their latest model, the PB3, which boasts the ability to output 8 kWh/day.
If you'd like to read more about marine energy generation, we did an article covering some of the best options out there.