Large breaking waves in offshore winds

Wave Energy

Wave Energy

Wave energy refers to the kinetic energy harnessed from the movement of swells in the ocean to produce electricity. Surfers have been utilising the power of waves for centuries and now it is one of the most promising renewable energy sources currently available.

1. How it works

2. Advantages

3. Disadvantages

4. The Future

5. Watch: Harness The Waves

Wave energy refers to the kinetic energy harnessed from the movement of swells in the ocean to produce electricity. Surfers have been utilising the power of waves for centuries and now it is one of the most promising renewable energy sources currently available.

1. How it works

2. Advantages

3. Disadvantages

4. The Future

5. Watch: Harness The Waves

How it works

The energy contained within the vertical motion of the waves is captured by Wave Energy Converters. Technologies can be split into shoreline, near-shore and offshore devices. Wave Energy Converters include buoy systems, water columns and tapered channel systems. These converters turn generators to produce electricity which can then be sent to the national grid as well as being used to desalinate water and pump water into reservoirs.

There is so much power contained within ocean waves; roughly 1000 times more kinetic energy than wind, with a 10ft high by 3ft length wave carrying enough energy to light 1000 bulbs.

The first patent of wave power technology belongs to Frenchman Monsieur Girard from 1799, however, fluctuating oil prices have always meant wave energy took a backseat within the area of renewable research until the first commercial wave power plant emerged in 2000 in the Isle of Inlay, Scotland. The LIMPET (Land Installed Marine Powered Energy Transformer) system was said to last for sixty years, requiring minimal maintenance and having high level of reliability; however, it was decommissioned completely by 2018.  

Wave energy converter

How it works

The energy contained within the vertical motion of the waves is captured by Wave Energy Converters. Technologies can be split into shoreline, near-shore and offshore devices. Wave Energy Converters include buoy systems, water columns and tapered channel systems. These converters turn generators to produce electricity which can then be sent to the national grid as well as being used to desalinate water and pump water into reservoirs.

There is so much power contained within ocean waves; roughly 1000 times more kinetic energy than wind, with a 10ft high by 3ft length wave carrying enough energy to light 1000 bulbs.

Wave energy converter

The first patent of wave power technology belongs to Frenchman Monsieur Girard from 1799, however, fluctuating oil prices have always meant wave energy took a backseat within the area of renewable research until the first commercial wave power plant emerged in 2000 in the Isle of Inlay, Scotland.  The LIMPET (Land Installed Marine Powered Energy Transformer) system was said to last for sixty years, requiring minimal maintenance and having high level of reliability; however, it was decommissioned completely by 2018.  

Advantages

The most encouraging aspect of wave energy is that it is a renewable source. Fossil fuels are finite, with danger of running out, but so long as the sun shines, the wind blows and the ocean currents continue to flow, we will have waves.

Energy generated from waves doesn't involve polluting the Earth's atmosphere either, as unlike burning fossil fuels, this energy is completely clean, with no harmful byproducts. Burning fossil fuels is said to provide 85% of the energy we consume, so by switching to renewable energy sources like wave power we will be able to cut our carbon emissions, which are largely responsible for our current climate crisis.

A surfer riding a wave
A surfer riding a wave

Advantages

The most encouraging aspect of wave energy is that it is a renewable source. Fossil fuels are finite, with danger of running out, but so long as the sun shines, the wind blows and the ocean currents continue to flow, we will have waves.

Energy generated from waves doesn't involve polluting the Earth's atmosphere either, as unlike burning fossil fuels, this energy is completely clean, with no harmful byproducts. Burning fossil fuels is said to provide 85% of the energy we consume, so by switching to renewable energy sources like wave power we will be able to cut our carbon emissions, which are largely responsible for our current climate crisis.

As the oceans cover 70% of the Earth’s surface, wave energy is abundant and widely available; there are many ways to tap into this source (with new technologies readily emerging) and it is considered more consistent and predictable than other renewables such as solar or wind. Not only that, it is noted as the most concentrated form of renewable energy. The energy density is typically around 30-40 kW for every meter (2.2 feet) of wave along the shore, this being the highest power density to be found amongst all the renewables.

Unlike other sources of energy, there is no damage to land when capturing wave power plus it only requires 1/200 of the land area of wind power. Without any roads needed to be built infrastructure, costs are much less.

Disadvantages

Unfortunately wave power is renowned for being susceptible to damage from rough seas. Of course utilising the kinetic energy of waves means projects being placed in locations that have access to them, but with that comes the danger of being exposed to extreme weather.

The financial implications of switching to wave power are not clean cut either. The waves may be free but production and installation costs of technologies teamed with complex maintenance and repair logistics mean the overall valuation of wave farms is likely to exceed wind and solar.

There are concerns about the effects of wave energy converters and wave farms on the local ecosystems. It could be extremely disturbing to delicate habitats and marine life that depend upon the coastline for their food and shelter. However, research from Streamlining of Ocean Wave Forms Impact Assessment states wave energy devices will most likely act as fish aggregating devices (FADs) and create an artificial reef effect with the potential to increase species and biomass abundance. Noise pollution produced from wave energy converters will inevitably affect the underwater world they appear in, yet studies in Denmark have shown they're unlikely to affect marine mammals, with more research underway.

It seems there has yet to be any evidence for significant negative impact on the environment, but experts agree great care must be exercised when scaling up to larger scale projects.

A coral reef surrounded by marine life

The Future

Wave energy has great potential in the renewable energy industry and there are still a number of innovations and trends taking place within the sector.   Expect to see more shifts happening, as the Europe 2020 strategy which includes a target of reaching 20% of gross final energy consumption from renewables by 2020 - means the heat is on to harness much more from our energy from natural sources.

The ocean is one of the most vast and powerful sources of energy on this planet; developing reliable, resilient, environmentally friendly and cost effective ways to harness its power is surely one panacea to our dependence on fossil fuels and a crucial step towards using clean energy.

As the oceans cover 70% of the Earth’s surface, wave energy is abundant and widely available; there are many ways to tap into this source (with new technologies readily emerging) and it is considered more consistent and predictable than other renewables such as solar or wind. Not only that, it is noted as the most concentrated form of renewable energy. The energy density is typically around 30-40 kW for every meter (2.2 feet) of wave along the shore, this being the highest power density to be found amongst all the renewables.

Unlike other sources of energy, there is no damage to land when capturing wave power plus it only requires 1/200 of the land area of wind power. Without any roads needed to be built infrastructure, costs are much less.

Disadvantages

Unfortunately wave power is renowned for being susceptible to damage from rough seas. Of course utilising the kinetic energy of waves means projects being placed in locations that have access to them, but with that comes the danger of being exposed to extreme weather.

The financial implications of switching to wave power are not clean cut either. The waves may be free but production and installation costs of technologies teamed with complex maintenance and repair logistics mean the overall valuation of wave farms is likely to exceed wind and solar.

A coral reef surrounded by marine life

There are concerns about the effects of wave energy converters and wave farms on the local ecosystems. It could be extremely disturbing to delicate habitats and marine life that depend upon the coastline for their food and shelter. However, research from Streamlining of Ocean Wave Forms Impact Assessment states wave energy devices will most likely act as fish aggregating devices (FADs) and create an artificial reef effect with the potential to increase species and biomass abundance. Noise pollution produced from wave energy converters will inevitably affect the underwater world they appear in, yet studies in Denmark have shown they're unlikely to affect marine mammals, with more research underway.

It seems there has yet to be any evidence for significant negative impact on the environment, but experts agree great care must be exercised when scaling up to larger scale projects.

The Future

Wave energy has great potential in the renewable energy industry and there are still a number of innovations and trends taking place within the sector.   Expect to see more shifts happening, as the Europe 2020 strategy which includes a target of reaching 20% of gross final energy consumption from renewables by 2020 - means the heat is on to harness much more from our energy from natural sources.

The ocean is one of the most vast and powerful sources of energy on this planet; developing reliable, resilient, environmentally friendly and cost effective ways to harness its power is surely one panacea to our dependence on fossil fuels and a crucial step towards using clean energy.

A photo of a wave from under the water

The theoretical annual energy potential of waves off the coasts of the United States is estimated to be as much as 2.64 trillion kilowatt hours, or the equivalent of about 64% of U.S. electricity generation in 2018.

A photo of a wave from under the water

The theoretical annual energy potential of waves off the coasts of the United States is estimated to be as much as 2.64 trillion kilowatt hours, or the equivalent of about 64% of U.S. electricity generation in 2018.