London — Before the end of the year, many farming communities in the remote Orkney Islands, north of Scotland, are to receive electricity from wind power. Farther south, Britain intends to install several hundred aerogenerators offshore in the stormy North SEa. The first -- a unit with 100-foot blades mounted on a 150 -foot tower -- shout generate a megawatt of electricity and may be erected within five years.
This underscores the fact that wind power is breaking through the cost barrier in its competition with conventional energy sources. The big wind machines are to produce power at a price comparable to that of nuclear electricity. The more modest units, already under construction in the Scottish isles, are expected to beat the prices of the existing local diesel oil generators.
According to conservative estimates, commercial wind-generated electric power could supply something like 20 percent of the world's energy requirements by the turn of the century. The implications are enormous, given the crippling effect of rising oil prices, particularly on the fragile economies of the developing regions.
A conference under the auspices of the United Nations Food and Agriculture Organization (FAO) recently agreed on the desirability of establishing farming settlements throughout Europe which would rely entirely on renewable energy supplies. These would be aimed partly to cut costs and partly to create models that could be studied and adapted to the needs of agricultural cooperatives in the developing countries. The global use of renewable energy supplies, including wind power, is to be considered at a world conference in Nairobi next year.
In Britain, the big wind machines are planned by the Central Electricity Generating Board (CEGB). Glyn England, its chairman, cautions: "An aura of romance still surrounds the subject of wind power in the minds of many people, who think in terms of the picturesque windmills of former centuries. But reality is in stark contrast. Consider the design of a 3.7 megawatt wind generator produced for the Department of Energy. It has two blades, slightly longer than the wings of a jumbo jet. Another design resembles a 10-story tower block with a propeller on top. Some designs are very like [electricity] transmission towers, about the same size as our largest."
The big aerogenerators are noisy and unattractive. They also produce electrical interference. Nevertheless, a discussion paper published by a panel of specialists preparing for the Nairobi conference considered their adverse effects on the environment to be minor compared with those of the existing power stations. It recommended rapid deployment of wind-power generators in the developing countries.
The United States is soon to launch development program based on the third-generation of experimental wind machines now under construction. Sweden, West Germany, and Denmark have already launched ambitious wind power programs.
Britain is to overcome the environmental effects of aerogenerators by locating "wind farms," each with dozens of individual machines, at offshore sites.
"There, they would be much less obtrusive," observes the CEGB chief. "Admittedly, it will be mofe difficult and costly to build and maintain the machines offshore than on land. There will be the extra expense of getting the power ashore. And they could be a hazard to fishing vessels. But wind speeds are higher there than over open land although not quite as high as on the best hilltop sites."
Most of the big aerogenerators so far are based on the horizontal axis model (reminiscent of traditional windmills or aircraft propellers). But Britain may well opt for the vertical axis design, copied from windmills used in the Middle East for hundreds of years, because it can utilize winds approaching from any direction.
The drawback of the program is that wind does not blow all the time. Even the new aerogenerators planned for the Orkney, Shetland, and Western Isles -- probably the windiest places in Europe -- will substantially complement, but not entirely replace, conventional power generation which can be relied upon in any weather.
This was recognized by the European Commission on Agriculture at a meeting organized by FAO when the commission noted a need to establish at least 15 model farms or villages self-sufficient in energy. These would rely on an integrated system of renewable power supplies from wind, sunshine, local water falls, hot springs, and biomass. In the long term, the project would lead to food production throughout Europe entirely independent of energy imports.
Small-scale wind energy conversion encompasses the needs of farmers and rural communities, especially for well pumping, cattle watering, irrigation, and domestic electricity supplies. Such systems were widely in use in industrialized countries until the advent of low-cot, mass rural electrification during the past 30-40 years. But the specialist panel preparing for the Nairobi conference comments that the new, small-scale wind machines now are often unpopular in many developing countries because the relatively high cost of the imported units, as well as their generally poor reliability.
These could be no more than the growing pains of the young industry. The direction of the future may well be demonstrated by experience in Kenya and Tunisia where machines of local manufacture have proved their usefulness in the rural areas where they are adequately serviced and promoted. The world conference is likely to magnify the call of the specialist panel for extensive facilities in the industrialized countries to train technologists from the developing regions in order to make the benefits of the industry globally available.