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Offshore Alternate Energy Moves Forward Despite all the controversy over the past years about Cape Wind's proposal to build a wind farm in Nantucket Sound, the project is moving forward. A couple of weeks ago, the lead federal permitting agency, the Minerals Management Service (MMS), completed the draft environmental impact statement. From now through March 20, 2008, MMS will accept written comments on the project and during March 2008 it will hold public hearings. Of more nationwide concern, last December the Department of Interior published a final decision regarding the Programmatic Environmental Impact Statement on the establishment of the Alternative Energy and Alternate Use Program for the Outer Continental Shelf. The shelf is an offshore area under federal jurisdiction, typically extending from 3 miles to about 200 miles out to sea. A Programmatic Environmental Impact Statement (PEIS) evaluates the environmental impacts of broad agency actions. Establishment of the Alternative Energy and Alternate Use Program is such an action; it involves implementing a program that sets the stage for site-specific actions to follow. In other words, the assessment is conducted in anticipation of environmental impacts that will results from an expected course of action—in this case, the permitting of offshore alternative energy facilities. The Secretary has adopted all but two of the 54 best management policies proposed based on the findings of the PEIS. So the final word is "GO", initiating the establishment of a federal seabed leasing program for alternative energy similar to what currently exists for oil and gas development. On the one hand, this is welcome news. It means that it will be easier to gain approvals for such facilities; the program will provide some bureaucratic certainty and systematic environmental review. However, it also means that more ocean development will occur and at a faster pace.  Attenuator Wave Energy Device Such development projects include: offshore wind energy, wave energy, ocean current energy, offshore solar energy, and hydrogen generation. MMS, the administrating agency, will also have jurisdiction over projects that make alternate use of existing offshore oil and natural gas platforms in federal waters. Alternate uses of platforms may include alternative energy production, aquaculture, and research and monitoring. While the design of offshore wind turbines is familiar, other offshore technologies are less known. For example, wave energy systems are situated in deep water, typically of more than 40 meters (131 feet). Various wave energy systems differ in their orientation to the waves and in the manner they convert energy. Wave technologies recently targeted for development are: terminator devices that capture or reflect the power of the wave, point absorbers that are floating structure with components that move relative to each other due to wave action and attenuators which are long multi-segment floating structures oriented parallel to the direction of the waves. Attenuators use the differing heights of waves to cause flexing, which occurs where the segments connect. Energy from the flexing is then captured by hydraulic pumps. Although farther behind in development as a usable resource, ocean currents carry a great deal of energy because of the density of water. For the same surface area, water moving 12 miles per hour exerts about the same force as a constant 110 mph wind. Under the most likely scenario, energy would be extracted from ocean currents using submerged water turbines similar to wind turbines. Solar technologies potentially suitable for offshore ocean environments include concentrating solar power technology and photonic technology. Hydrogen is an energy carrier, not an energy source. Offshore wind, solar, and wave energy do not always produce energy at the time at which it is needed. Hydrogen could be produced offshore at the point of energy generation in a co-located facility, or at an onshore location, utilizing the energy generated at the offshore power generation facility. Hydrogen could be delivered to onshore facilities as a gas, in liquefied form, or in a hydrogen carrier. All of the alternative forms of energy generation are good in that they reduce our dependence on burning of fossil fuels, thus reducing carbon dioxide emission and global warming. But at the same time, some environmental perturbation can be expected from each of them. As usual, trade-offs must be made wisely and in a timely manner. Michelle Portman PhD is a postdoctoral fellow in the Marine Policy Center at Woods Hole Oceanographic Institution. |
