Fraunhofer USA Looks Beyond Traditional Wave Harvesting Technology

Fraunhofer USA Looks Beyond Traditional Wave Energy Harvesting Technology
Fraunhofer USA Looks Beyond Traditional Wave Energy Harvesting Technology

Traditional Wave Harvesting Technology Challenged.

The Fraunhofer Center for Manufacting Innovation or CMI conducts applied research and development leading to the deployment of technological solutions that enhance the productivity and competitive position. CMI is also an very well respected engineering school. 

Overcoming The Drawbacks of Traditional Wave Energy Harvesting Technology.

Conventional approaches to harvesting energy from ocean waves and currents suffer from at least three major drawbacks:

1) expensive underwater power transmission cables,

2) storm damage susceptibility, and

3) energy output cannot be scheduled according to demand.

These factors translate into more expensive electricity (cost/KWH). Consequently, market economics hinder deployment and use of ocean energy, and the technology is only moving forward due to government incentives.

Mobile wave energy harvesting boats could bring cheaper clean electricity

CMI is pursuing an economically viable, alternative method of harvesting ocean wave energy, comprised of a boat with an on-board wave energy harvesting system, and on-board energy storage capacity. A typical system consists of 50 meter boat with 1 MW capacity wave energy harvesting equipment and 20 MWH of energy storage capability.

alternative method of harvesting ocean wave energy

Alternative method of ocean wave energy harvesting.

Operationally, the boat cruises to a favorable location off-shore, harvests energy for approximately 20 hours, cruises back to shore, connects to the electricity grid, and releases the stored energy during high demand periods. Preliminary calculations promise initial electricity cost of 15 cents per KWh.

The proposed concept is a modular, distributed energy system in which numerous such small boats harvest wave energy off the entire coast-line. This means that the energy is produced near the point of use, eliminating the need for new infrastructure, like high power transmission lines typically needed for wind energy, or special docking facilities, as conventional marinas suffice.

Wave Energy Harvesting Project Highlights:

  • Harvests wave energy with daily trips to offshore locations and returns back to port for delivery to the grid
  • Energy is stored locally on the vessel during harvesting phase
  • Energy is placed on the grid during periods of high demand (normally mid-day),
  • Eliminates expensive undersea power cables needed for other wave energy technologies,
  • Can be moved safely to port during severe storms,
  • Overcomes regulatory hurdles by not being a permanent structure.

The video is animated and at first glance seems a bit simplistic. For example it assumes that sonehow we can store the energy on the boat in an efficient manor. I suppose it could be batteries to store electricity after it is generated or it could be high pressure gas, stored from the kinetic energy of the waves. For the later, this stored kinetic ( potential energy) would be transferred onshore where it would be used to generate electricity.

This method would allow for easier maintenance and avoidance of adverse weather conditions. A permanent wave generator installation is hard to move around especially when it is scaled up.

So, for the arm chair clean energy experts out there, what do you think of this design for mobile wave energy harvesting?

About Gordon Smith
Gordon's expertise in the area of industrial energy efficiency and alternative energy. He is an experienced electrical engineer with a Masters degree in Alternative Energy technology. He is the co-founder of several renewable energy media sites including Solar Thermal Magazine.

Leave a Reply

Your email address will not be published.