Increasing awareness of the need for green living has prompted considerable research activity in every walk of life in the US. The vigorous effort to identify sustainable sources for generation of clean energy is a case in point. For quite some time, , ideas of a "bridging fuel' have diverted attention to ethanol and, lately, to liquefied natural gas. The clamour for a lasting alternative to fossil fuels has, indeed, helped kick-start intensive research pro grammes. Resolution passed As if to provide the drive to emerge from the present "bridging fuel' syndrome, a far-reaching resolution has been passed by a federal legislation, mandating that 15 per cent of electricity be generated through renewable sources. Tax incentives, too, are included in the Bill, to incentivise private utility companies. The focus now seems to be shifting to the elements. The sun, the winds and the ocean are likely to become the most reliable sources for green power. Solar power, though acknowledged for long as the most acceptable among the renewable sources, still has severe limitations impeding wide-scale adoption. Hence, the strong contenders for the ultimate coveted spot in the clean energy race could, perhaps, be the wind and the waves. Towering wind turbines Already, several landscapes, particularly in Washington and Oregon, have become homes to clusters of tubular columns towering high, with wind turbines perched on top. Advanced technology in the latest versions of wind turbines allows generation even at wind-speeds of as low as 8 mph. These huge generators form a panorama of impressive structures, standing tall at nearly 400 feet with wide sweeping blades and capable of yielding of 3-5 MW. Leading power generation companies are investing in a wind farms in Washington, which alone has the potential to produce enough energy to meet the needs of over 100,000 homes. Turning to the waves In looking to the elements for the right solutions, thoughts are now converging also on ocean waves. A Bill is likely to provide a federal grant of $250 million towards research in this unexplored area. The long Oregon coast, it is estimated, may carry in its waves the capacity to generate more than 14,000 MW, far in excess of the State's present requirements, thereby, permitting a fair contribution to the national grid. At present, Oregon State University (OSU) is involved in vigorous research and has built a prototype on a floating buoy off Portland. This unit incorporates a set of moving coils around a fixed magnetised shaft anchored to the sea floor. As these coils move up and down, forced by the roiling waves, electricity is produced. As soon as technological barriers are overcome, the ocean's waves would surely prove to be the final answer in the long quest for a clean energy source. Sources of concern However, while winds and waves present amazing prospects for extraction of green power, one cannot ignore the concerns of environmentalists and lawmakers. Ornithologists, bird-lovers and prominent members of the Audubon Society, who had worked hard to bring back some avian species from the brink of oblivion, are naturally alarmed at the proliferation of these monstrous machines with whirling blades at great heights. They could draw thousands from the migrating flocks on to a deathly collision course Likewise, to what extent the ocean-based electrical generators would damage marine ecology is yet to be seen. It is a sad feature that in the attempt to harness nature in the name of development what may appear useful or acceptable to one may mean death or destruction to another. (The author is a Chennai-based freelance writer.)