Harnessing the energy in the waves is full of opportunities to current energy systems. Wave energy is a concentrated and highly available energy source. It is close to dense populated areas and is well distributed around the globe. The visual impact is minor, the environmental impact is significantly low and it comprises an energy supply present in our planet in a continuous way. Moreover, wave energy can be predicted with good accuracy and is more constant than wind energy.
Nevertheless, the way ahead for wave realisation is beset with difficulties, particularly related to testing in real seas, due to the characteristics of ocean waves and to the costs (WEC, 2010).
In contrary to many other technologies’ advancements, WECs have to be tested in real seas from a certain prototype scale onwards (this scale depends on the WEC´s and on the laboratory dimensions). Sea trials are generally more complicated and expensive than laboratory testing. Permits often have to be applied for as if a conventional power plant was being installed, and the public usually has also a say. The deployment also requires suitable weather windows and specialist vessels (usually hired by the oil and gas industries). More importantly, the prototype has to be designed to survive to extreme events and operate in harsh environments, despite being a test plant.
All these strongly affect the project’s costs, which is characterised by capital intensive technologies. The infrequent extreme conditions at the deployment location dictate the structural design of the WEC, which is directly related to the capital costs of the WEC. However, the return of investment is given by the frequent low and medium wave states. And this also applies to early stage small scale sea prototypes.
In addition, the wave energy sector requires the development of new manufacturing systems, with novel product lines and expertise. Nevertheless, whereas most of the industries start nationally and expand later, wave energy has already reached the international dimension.
Reserves of oil, coal, gas and uranium are undoubtedly getting to an end, and new discovered non-renewable energy fields such as shale gas and oil sand can have irreversible environmental negative impacts. It seems the change from current conventional energy supplies to renewable energy systems is imperative.
At this point, the continuous potential of wave energy should not be underestimated. Above all, wave energy is a promising exploitable energy source that could provide enormous advantages to energy systems.
Continue reading: Recommended bibliography for wave energy
WEC. (2010). Survey of Energy Resources. World Energy Council (WEC).