Why pursue Wave Energy?

SIGNIFICANT POTENTIAL SUPPLY

Ocean waves represent our planet's last untapped large-scale renewable energy resource. Over 70 per cent of the earth's surface is covered with water. The energy contained within waves has the potential to produce up to 80,000TWh of electricity per year - sufficient to meet our global energy demand five times over.

GREATER PREDICTABILITY

Ocean waves are generated by wind passing over the surface of the sea - a process which often begins many hundreds or thousands of miles from shore. Because waves originate a long way from shore, computer models of wave propagation allow us to accurately forecast incoming waves up to five days in advance.

In comparison with wind or solar energy, it's easier to accurately predict how much and when energy can be generated. Because the peaks and troughs of wave energy are not in synch with those from wind or solar, combining the power from these sources acts to even out their combined output, leading a more predictable and steady renewable energy mix.

A diverse renewable energy portfolio will lead to a more stable energy system, reduced variability and lower cost. In addition, a strong renewable energy mix means we become less reliant on traditional power sources such as oil and gas. This will lead to greater energy security.

LOW IMPACT

Wave energy is, by its nature, a clean energy resource. Aside from the energy expended in manufacture and installation of wave energy devices, it produces no carbon emissions. While environmental impacts for large-scale power plants of any type need to be studied at a local level and will might differ from one technology to another, our engagement with experts at the DOE’s Pacific Northwest National Laboratory suggest confirm that Triton should have a negligible impact on the aquatic environment.

WORLD WAVE ENERGY RESOURCE MAP

The world's most energetic waves are found on the US West Coast, Northern Europe, Chile, Australia and New Zealand, but there are many areas around the world where wave energy could prove cost competitive.

OCEAN ENERGY STILL AN UNTAPPED RESOURCE

Despite its massive potential as a source for renewable energy, the ocean is unlikely to contribute meaningfully to electricity supplies without dramatic, innovation-driven improvements in average energy production, installed capital cost and reliability that deliver cost-competitive electricity to the grid. Traditional system concepts, using traditional and/or complex drivetrain solutions, have been unable to deliver the wide-band response required for high energy production or the reliability required for low maintenance costs.

“Wave energy is generally considered to be the most concentrated and least variable form of renewable energy. It is the high power density of wave energy that suggests it has the capacity to become the lowest cost renewable energy source. The World Energy Council has estimated that approximately 2 terawatts (2 million megawatts), about double current world electricity production, could be produced from the oceans via wave power.”

– Center for Wave Energy

UNDERSTANDING WAVE POWER

POWER FROM WAVES?

Ocean waves are energy being transferred across the ocean surface and are described by a wave height and a wave period.

The red dots in the image below represent water particles which go around in circles and do not travel with the wave.

Real seas comprise waves with many different heights and periods which is why the ocean surface appears so irregular.

The power available in each sea state is calculated per meter of wave crest. This means that the numbers in the chart above should be multiplied by the device width to provide the incident power. The power in the wave varies with the square of the wave height so there is a large variation in the available power.

RESONANT POWER TRANSFER

We can describe a wave energy system as a simple oscillator. The natural period of oscillation is determined by its mass and spring constant. Maximum power is captured when the wave period matches the natural period.

VIABILITY - ENERGY CAPTURE

This chart shows the probability of each sea state for a northern Oregon location. The majority of wave periods are between 5-10s. The larger systems have longer natural periods and increase energy capture.

WELL MATCHED WITH ELECTRICITY DEMAND

In the US, and in many countries around the world, population and electricity demand in coastal areas is growing faster compared to national averages. In many locations around the world the variability of waves can be seen to match daily and seasonal electricity demand. The net effect is that electricity from wave energy can be used when produced with only minimal requirement to store the energy. In fact, the consistency of energy from waves and the better alignment with grid demand means that much less storage is required compared to an equivalent solar or wind project in most locations. Furthermore, in locations such as the US West Coast, wave energy tends to peak when solar energy is low, and thus wave and solar can actually complement each other to improve power flows within utility grids.