Harnessing the tides
Imagine powering Cape Town using the waves on the west coast. Or surfing the internet on the power of the surf. The ideas are not pie in the sky and, with South Africa's abundance of powerful waves, a definite probability to power our economy in the future.
Ilham Rawoot, Johannesburg, South Africa, Mail & Guardian Online, Jun 07 2009 06:00
Natural energy heavy storm surf pounding the KwaZulu-Natal coast at Umdloti, north of Durban (above) and an artist’s impression of a wave farm (left) Photo: Netcare 911/Sapa and Pelamis Wave Power
"Wave power seems like the perfect idea," says Peet du Plooy of the World Wildlife Fund (WWF). He believes wave power's greatest benefit is that it is continuous, providing baseload, or 24/7, renewable electricity. It will mean that coastal cities can receive power without having to use the expensive transmission lines that are needed to send electricity cross-country, and which often cause losses of electricity along the way.
According to Professor Wikus van Niekerk, director of the Centre for Renewable and Sustainable Energy Studies at the University of Stellenbosch, another benefit to South Africa of using wave power is that it diversifies the mix in renewable energy.
"In summer we have large amounts of wind," says Van Niekerk, "and in winter we have big waves. The two complement each other. We can't power South Africa solely from wind or wave. We need to diversify."
Investec, which is working with British energy company Ocean Power to review the feasibility of wave power in South Africa, calls the energy source "a viable and commercial source of commercial and renewable power". Investec's Australian counterpart recently signed an agreement with Carnegie, to "assist them with the funding of future projects over the coming years".
While some people fear that collecting wave power will interfere with the natural order, ultimately creating tsunamis and killing marine life, the experts say it has no negative effect on the environment. "The ocean is huge," says Du Plooy. "Wave power is benign with respect to the local ocean environment."
But even though wave power seems like an environmental dream come true, it's taking a while to get off the ground. First, it's too expensive right now for the South African consumer. "It will probably cost 10 times more than coal-based electricity, if not more," says Van Niekerk.
Du Plooy says that coal-based electricity can be generated for between 20c/kWh to about 55c/kWh, depending on the age of the station. The initial price of wave power would be approximately R3/kWh. This would, however, decrease substantially with time, by about 75%, as innovation and scale increases. He says there also appears to be little government incentive for investing in wave energy. "Nersa's [National Energy Regulator of South Africa] announcement on feed in tariffs mentions four technologies, but not wave power."
Van Niekerk says that we probably won't see any commercial wave power plants in South Africa for at least the next five years, but they may spring up internationally within two years.
Norman Ndaba, director and sector leader of Ernst & Young's Utilities sector, says that there are still large amounts of research to be done before wave power will come into play. "Solar, wind and hydro are more plausible right now," he says. When asked how long it will take before we use wave power, he replies: "How long is a piece of string?"
Wave power alone cannot power South Africa. We have sufficient resources only along the south and west coasts, which end at East London and the Orange River, says Van Niekerk.
Ndaba says, "We can't wait for a storm to create electricity". He believes it is a great idea for wave power to be harnessed for use along the coast, but we should look at different, more suitable options for areas inland. But it took solar power 15 years to be commercially viable, he says, so we must not give up on wave power. Plus, as Van Niekerk says, a major reason we care about wave power, is because "it's fun!"
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