Ocean/Tidal/Stream Power: The Road to Commercialization

Ocean, tidal and stream energy are renewable resources that we should seriously consider as an addition to our global portfolio of energy supply alternatives. Here's why:

– The wave and tidal/stream hydrokinetic energy resource available to be converted to electricity is significant;
– The technology to convert those resources to electricity is emerging and is ready for testing in natural waters;
– Wave and tidal/stream hydrokinetic energy can be cost competitive with other renewable technologies; and
– We can overcome the significant challenges that remain to finding the pathway to commercialization of wave and tidal/stream energy technologies. 

The conversion of ocean wave energy, in-stream tidal, open-ocean and river currents into electricity will be the subject of much discussion at HydroVision International 2010, July 27-30, in Charlotte, N.C. It should not be confused with conventional hydro using a dam, impoundment or diversionary structure.

A robust electricity system of the future will be a balanced and diversified portfolio of energy supply alternatives. Our oceans are a public resource held in trust and accommodating multiple users. Fishermen make their living from the ocean and commercial ships navigate the oceans to deliver goods. Recreational boaters, surfers and those who just walk on the beach enjoy the ocean, while whales and other aquatic life make the ocean their home. Ocean energy could be one of those users working in harmony with other users and providing renewable energy for the overall good of our society.

The advantages of ocean energy are numerous. Studies have indicated that the high power density (kW/m2 for currents and kW/m of wave crest length for wave) of the resource results in smaller energy conversion machines lower in capital cost than other renewable technologies. The remoteness and hostility of the ocean environment, however, can result in higher deployment, operation and maintenance costs. But on balance, the cost of electricity can be comparable or lower than power produced by other renewable technologies.

Other benefits include: Providing a new, relatively environmentally benign, renewable source for meeting load growth and renewable portfolio goals; easy assimilation into the grid (because of the predictability of the resource); easing transmission constraints (since a large percentage of the world's population lives near a coast) with minimal, if any, aesthetic concerns; reducing dependence on imported energy supplies and increasing energy security; lowering the risk of future fossil fuel price volatility; reducing emissions of greenhouse gases compared with fossil fuel-based generation; and stimulating job creation and economic development by using an indigenous resource.