Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Predicting Wave Power Could Double Marine-Based Energy

11.09.2012
Forecasting wave height one second in advance optimizes energy collection, says a TAU researcher
In the search for alternative energy, scientists have focused on the sun and the wind. There is also tremendous potential in harnessing the power of the ocean's waves, but marine energy presents specific challenges that have made it a less promising resource.

It's a challenge to tune Wave Energy Converters (WECs) so that they are able to harvest the maximum energy from waves, which differ in terms of their size and force. This unpredictability leads to intermittent energy collection. WECs also need to withstand the harsh winds and storms to which they are subjected in the open sea — storms which can destroy the devices.

Now, working with a team at the University of Exeter in the UK, Prof. George Weiss of Tel Aviv University's School of Electrical Engineering and Center for Renewable Energy has developed a control algorithm that, when used in conjunction with previously-developed wave prediction technology, helps WECs calculate the correct amount of force needed to collect the maximum energy possible, allowing the device to respond to each wave individually. The system, which was recently published in the journal Renewable Energy, doubles the energy previously collected by WECs.

Calculating force

WECs, Prof. Weiss explains, have two parts — a fixed or weighted lower part, possibly attached to the ocean floor, and an upper section that moves up and down based on the motion of the water. The device collects energy generated by the resistance force between the parts. Unlike wind turbines or solar panels, which collect as much or as little energy as comes their way, WECs need to adjust themselves to each oncoming wave to function properly, which requires knowledge of the characteristics of the incoming wave.

If there is zero resistance between the two parts of the WEC, the upper part moves freely with the waves, and no electricity is generated, Prof. Weiss explains. On the other hand, where there is so much resistance that it suppresses movement, the device turns rigid. At both of these extremes, no energy is produced. The ideal is a happy medium based on measurements of the incoming wave.

Prof. Weiss and his fellow researchers developed a control algorithm that is responsible for setting the correct resistance force for the WEC based on the predicted wave information. A processor attached to the WEC runs the algorithm five times per second in order to determine and then implement an optimal mechanical response to the coming waves.

In the lab, the researchers have run simulations using wave data gathered from the ocean. Combining prediction technology with their new algorithm, energy collection was improved by 100 percent —double the amount of energy that WECs had collected previously.

One second warning

The most important piece of information is the height of the wave, says Prof. Weiss, which the WEC needs to know in advance in order to prepare. "You would think that the longer the WEC knows the wave height in advance, the better, but in a surprising finding, it turns out that a one-second prediction horizon is enough," he says, noting that a longer prediction time does not actually improve the energy harvest.

Their findings could not only help to improve the functioning of the WECs that are already in use in places such as the East Coast of the US and the Atlantic Coast of Spain, but could help the technology become more competitive. Currently, marine energy is fifty times more expensive to collect than the market price for the energy itself — as solar and wind energy were in their infancy, says Prof. Weiss. But with the improvement of WEC structure, performance, and mass production, it could become commercially viable. "There is a lot of untapped energy in the ocean," he adds.

George Hunka | EurekAlert!
Further information:
http://www.aftau.org

More articles from Power and Electrical Engineering:

nachricht Scientists create biodegradable, paper-based biobatteries
08.08.2018 | Binghamton University

nachricht Ricocheting radio waves monitor the tiniest movements in a room
07.08.2018 | Duke University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: New interactive machine learning tool makes car designs more aerodynamic

Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.

When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...

Im Focus: Robots as 'pump attendants': TU Graz develops robot-controlled rapid charging system for e-vehicles

Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.

Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....

Im Focus: The “TRiC” to folding actin

Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.

Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...

Im Focus: Lining up surprising behaviors of superconductor with one of the world's strongest magnets

Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur

What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...

Im Focus: World record: Fastest 3-D tomographic images at BESSY II

The quality of materials often depends on the manufacturing process. In casting and welding, for example, the rate at which melts solidify and the resulting microstructure of the alloy is important. With metallic foams as well, it depends on exactly how the foaming process takes place. To understand these processes fully requires fast sensing capability. The fastest 3D tomographic images to date have now been achieved at the BESSY II X-ray source operated by the Helmholtz-Zentrum Berlin.

Dr. Francisco Garcia-Moreno and his team have designed a turntable that rotates ultra-stably about its axis at a constant rotational speed. This really depends...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Within reach of the Universe

08.08.2018 | Event News

A journey through the history of microscopy – new exhibition opens at the MDC

27.07.2018 | Event News

2018 Work Research Conference

25.07.2018 | Event News

 
Latest News

'Building up' stretchable electronics to be as multipurpose as your smartphone

14.08.2018 | Information Technology

During HIV infection, antibody can block B cells from fighting pathogens

14.08.2018 | Life Sciences

First study on physical properties of giant cancer cells may inform new treatments

14.08.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>