CorPower Ocean’s point absorber technology is simple and self contained.
Stockholm, Sweden-based Corpower Ocean has developed a standalone generation source the company calls a Wave Energy Converter, a floating generator unit tethered to a seabed anchor. The converter is essentially a floating buoy, resembling a giant sport fishing float or “bobber,” containing a novel mechanism. As the converter rises and falls relative to its seabed anchor, the vertical motion is converted by a rack and pinion mechanism into rotation, driving generators. The technology has been tested in real-world conditions since 2018 and has little environmental impact on marine life. Ocean wave power resources globally are approximately 500 GW, enough to potentially supply 10% of the world’s electricity needs.
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Episode Transcript:
The recent COP 28 climate conference in Dubai was centered on possible timelines for a phase-out of fossil fuel use globally. It’s a highly contentious issue, with the oil industry strongly represented for the first time at a major climate change event. Solutions to rising CO2 levels in an energy-hungry world are, of course, engineering solutions. And at COP 28, two approaches were discussed: carbon sequestration and alternate energy sources.
Solar photovoltaic and wind, along with nuclear power, are the most popular forms of alternate energy in use worldwide, but there are others that have outstanding output potential with sensible economics. One that gets relatively little attention is wave power.
Stockholm, Sweden-based CorPower Ocean has developed a standalone generation source the company calls a Wave Energy Converter, a floating generator unit tethered to a seabed anchor. The converter is essentially a floating buoy, resembling a giant sport fishing float or “bobber,” containing a novel mechanism. As the converter rises and falls relative to its seabed anchor, the vertical motion is converted by a rack and pinion mechanism into rotation, driving generators. The device uses a pneumatic pretension linkage which addresses the inevitable resonance problems encountered in any wave harnessing technology. The system allows the floating mass to be tuned in or out of phase with the incident waves, both optimizing electrical output and damping the unit’s motion as necessary in rough seas. Sealing rotating elements such as turbines against seawater ingress has always been a challenge for ocean power systems, but the Corpower device oscillates vertically, simplifying the sealing problem with slower, purely linear motion in the moving element.
Unit hulls are produced as fiber-wound composite monolithic structures, which are built on site using a mobile factory. Wave Energy Converters weigh 70 tons, in a 9 x 18 m footprint, producing 300 kW. According to the company, this represents an energy harvest using 1/10 of the volume of conventional wave energy conversion technology.
In development since 2012, and initially tested in 2018, the CorPower system will be deployed in numbers to form local networks for grid scale power production, with full commercial rollout in 2025. The total addressable market is considerable. Current estimates of commercially feasible wave energy resources are about 500 GW, of which just over 330 GW are expected to be in use globally by 2050. Wave energy could deliver 10% or more of the world’s electricity needs if deployed fully. Plus there is an additional environmental bonus: the Wave Energy Converters have minimal impact on marine life.