Alternatives’ new wave

The ocean has huge potential to produce renewable energy – and there's now a way to overcome some of the problems traditionally associated with wave power.

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In the race to generate renewable energy, one source has been largely overlooked – the ocean. That’s a shame, as its waves have the potential to provide twice as much electricity as the world produces now, according to the World Energy Council.

Thanks to two Israeli entrepreneurs we may now be one step closer to fulfilling that potential. They have developed technology for extracting energy from waves and converting it into electricity.

“It’s a very simple system, with 90 per cent of the equipment on land and just 10 per cent in the water,” says Inna Braverman, who co-founded Eco Wave Power together with David Leb.

Keeping the bulk of the equipment on land helps reduce some of the challenges traditionally associated with wave power, such as high deployment and maintenance costs, risk of corrosion and the potentially negative impact on marine life.

“It requires no ships or divers and there’s easy access for maintenance, unlike competing marine generation technologies, which operate mainly offshore. And it can generate power at night or in polluted atmospheres, unlike solar power.”

The EWP system is based on simple floaters attached to structures on the shore such as breakwaters. They rise and fall with the waves, creating hydraulic pressure that can be piped to buildings on dry land to turn motors and generate electricity. Smart automation controls the process to smooth power generation and feeds it into the grid: if the waves become too rough, it can raise or lower the floaters to protect them from damage.

Ten floaters make up a module for power generation, which is capable of generating one megawatt of power – enough to supply around 1,000 households. They can be attached to any man-made structure, including jetties, piers and platforms as well as breakwaters, and can be adapted in size and arrangement to suit the space and climate.

A pilot project is already in operation in Gibraltar, where the equipment has proved its capacity for withstanding storms. With an initial capacity of 100KW, it is the first commercial wave energy array in Europe, selling its electricity to the grid.

power of waves

Braverman and Leb are optimistic about the prospects, aiming to install 130MW of capacity over the next five years in including increasing Gibraltar’s capacity to supply 15 per cent of the territory’s electricity needs, as well as projects in Israel, Mexico and China. Most of the installations can be made from locally manufactured steel with only the smart operating system imported from Israel. And local people can be trained to maintain the plant once installed.

Crucially for viability of the project, their wave energy can already compete on price with solar power and can become cheaper still through economies of scale. Since the density of water is 800 times greater than the density of air, much greater amounts of electricity can be generated with much smaller devices. In Israel, for example, the 3.5 kilometres of breakwaters along its coasts could accommodate wave power generators of 50MW – enough to supply 50,000 people.

Eventually, with just over half the world’s population living within 200km of the sea, wave power has the potential of becoming one of the major sources of power, says Leb: “It will be part of the renewable big picture, with solar, wind, biofuels and others – there won’t be just one power source like fossil fuels.”