S'pore testing waters with tidal energy

Singapore is dipping its toes into a new source of clean energy besides solar power - the ebb and flow of tides.

The country's first tidal turbine system - also the first to be installed in the tropics - has been set up just off Sentosa.

A one kilowatt testbed generator was launched on Wednesday beside the Sentosa boardwalk. Using the movement of tides as energy, the power produced may only be enough to light up a nearby exhibit, but it is a start as researchers investigate optimum turbine designs and viability.

Tidal energy has conventionally only been generated in temperate regions such as Britain and the US. Tidal ranges are higher there, meaning more energy produced.

The test turbine is designed and constructed by Nanyang Technological University's Energy Research Institute (Eri@n), and partly funded by the Ministry of Trade and Industry and Sentosa Development Corp. Funding details were not revealed.

To accommodate slower tidal flows here of up to 2.5m per second, the turbine blades are just 60cm long, compared to about 9m in, say, Scotland - which makes them smaller and cheaper.

Eri@n plans to test more tidal turbines in Singapore's southern waters within the next three to five years, including off St John's Island and Pulau Sebarok. The mapping it has done shows that tidal flows in these areas are among the fastest here, said research fellow Michael Abundo. Installing more such energy-producing turbines could compensate for the weaker tides, he added.

Based on the institute's assessments, the southern waters could have, within 15 years, up to 200 tidal turbine systems generating 200MW-peak of energy - the maximum power generated under optimum conditions - which is enough to power 5,000 HDB flats. These would have to be located in areas with little maritime traffic.

Dampening the enthusiasm for tidal energy, however, the Energy Market Authority has said that for Singapore, marine renewable energy is limited as a lot of sea space is used for ports, anchorage and shipping lanes.

Still, Eri@n's executive director Subodh Mhaisalkar, said: "Tides are extremely predictable because they are completely defined by the phases of the moon, unlike solar or wind. (Tidal power) makes perfect sense, given that there's plenty of water around Singapore."

About 80 per cent of Singapore's energy needs are met by natural gas. The country is also ramping up its use of solar energy, the only renewable energy source currently connected to the national grid.

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