Bright source

There is general agreement that we need to find alternative energy sources to polluting fossil fuels such as coal and oil that are carbon-rich and produce carbon dioxide, carbon monoxide and particulate matter in the air. Among the "green" alternatives are wind power, wave power and solar power. Of these solar power seems the simplest, after all we live from the energy of the sun through plant photosynthesis and animal consumption of plants and other animals.

This idea has been around for at least forty years when Arnold Goldman came from the US and established the company Luz in Israel in the 1970s to harness the sun's rays for energy production. But, the costs were prohibitive then compared to cheap fuel, until the cost of gasoline approached $70 per barrel. Then with various forms of incentives, such as subsidies and tax breaks, alternative enrgy sources began to be competitive. Almost everywhere you go now you see wind farms, vast expanses of huge turbines on windy land. But, solar energy has been slower to take off. Now however, the largest solar farm is being built in California in a place called Ivanpah in the middle of the Mojave desert by a company named BrightSource Energy, with the support of the California and US Governments. At its opening recently Gov. Arnold Schwartznegger said "Some people look out at the desert and see miles and miles of emptiness, but I see miles and miles of a gold mine, a gold mine of great, great opportunities." The company BrightSource is an inheritor of Luz, and although it is working in California, much of the know-how was developed in Israel. It is unfortunately true that the US and California is a more attractive location for this development, but hopefully the Israeli Government will soon realize that it is lagging behind.

All alternative energy sources have drawbacks. Solar power has two, how to focus enough of the sun's rays on a box to boil enough water to produce electricity through a dynamo, and how to keep the mirrors clean. As to the first issue, the Ivanpah power station will start out with ca. 1,000 large curved mirrors to produce 370 Mgw of power. All of the mirrors must be focussed on a single target upon a tower. How to keep them focussed when the sun moves across the sky, well of course the mirrors must move too. But each one must move in a distinct arc, and this must all be controlled by computers, and the program to enable this was developed in Israel. Also, in a desert environment the mirrors quickly become covered in dust/sand, thus reducing their efficacy. So there must be a continuous cleaning of the mirrors. How to do this? Israeli technology developed a vehicle on tracks that automatically travels along the rows of mirrors and washes them clean with a high velocity spray of water. Of course, all this is expensive and complex, but the technical difficulties seem to have been solved and we can hopefully look forward to a bright future of solar power.
(This blog is partly based on an article by Hilary Leila Krieger in the J'sam Post Magazine 3/12/10 at: http://www.jpost.com/Magazine/Features/Article.aspx?id=197653 )