The U.S. Department of Energy has just unveiled a floating off-shore wind platform that it thinks could make a big splash. But it has already been working hard to commercialize “tidal energy” that uses underwater turbines to create electricity, which must then be wired into the grid.
Smaller tidal facilities are being tested. One such project has begun off the shores of Newport, Ore., where underwater turbines using 10 buoys will generate 1.5 megawatts of power. Impediments to further growth are wide ranging and cover such issues as the preservation of aquatic resources, water quality and the maintenance of marine life. In the end, regulators — who are trying to diversify the nation’s energy mix with green fuels — have concluded that wave energy is a valued part of the plan and that it is more predictable than wind or solar.
The Pacific Marine Energy Center is examining the potential and sending the data to scientists and engineers for further analysis. The Energy Department has chipped in $4 million to see the project through, which says that tidal power has the potential of providing 15 percent of electricity by 2030 that this nation produces.
The Oregon endeavor, which is being deployed by Ocean Power Technologies, is the biggest so far. But that project is not the only one: Ocean Renewable Power Co. has an undertaking at Cobscook Bay in Maine, and it has been working with the local utility, Bangor Hydro-Electric, to deliver power. It will eventually produce 300 kilowatts. And, Verdant Power just finished demonstrating a phase of its Roosevelt Tidal Energy Project in New York City’s East River. That would ultimately consist of 30 35-kilowatt tidal energy turbines — a project that is expected to get officially underway by 2015.
All of this has preceded the latest Energy Department announcement, which is the floating wind turbine off of Maine’s coast. The agency says that Maine’s waters are too deep for conventional wind turbines, which makes it a necessity to find other options if new renewable energy opportunities are to expand. Altogether, the agency wants to have 10,000 megawatts off-shore wind energygenerated by 2020.
Such sustainable energy, along with tidal energy, are the next big wave. A joint analysis done by the Energy Department and Georgia Tech say that the West Coast, which includes Alaska and Hawaii, are excellent prospects. It says that Maine has the best odds of success on the East Coast. What does tidal energy have that wind and solar do not? A continuous flow of water that won’t disrupt reliability.
The Electric Power Research Institute performed feasibility studies in this area. The Palo Alto, Calif.-based research arm of the electric utility sector said that unlike hydropower, tidal energy does not require the permanent impediment of water flow and the subsequent harm to aquatic life. Existing tidal plants, it adds, impound the water before releasing it into generators. And newer tools are even more progressive and use underwater turbines that ultimately connect to cables to transport the power.
Scientists and engineers must still show that their work can be done on a large-scale basis. And rough waters lay ahead. Environmentally, tidal power plants can impede sea life migration and can affect local ecosystems. The optimal solution, says the Energy Department, is to carefully select sites that preserve scenic shorelines.
Economically, barriers also exist. Operational costs are reasonable. But building and maintaining those plants is expensive. Therefore, the return on investment takes a long time. It is furthermore problematic when it comes to getting the power to shore. While generally predictable, tidal energy is still not as dependable as fossil-fired or nuclear generation.
But if the existing commercial and pilot projects prove out, then it would encourage other developers to get on board. With more experience and with the mass production of the essential technologies, prices would come down. At the same time, newer technologies that are around today are less problematic and don’t block migratory paths.
While wind and solar power are the most technologically advanced forms of green energy, tidal energy is also generating excitement. Using underwater turbines will start out by making ripples. But if the demos prove successful, tidal power’s reach could expand.