Sir, - James Kenny was surely mistaken (June 22nd) when he said: "By that time [2010], solar [energy], in all its forms, will be `mainstream'." Don't get me wrong. I approve of using solar power. I'm an environmentalist, and have some degree of familiarity with alternative energy sources.
Space and some forms of power generation are of interest to me. Photoelectric (solar) cells are criticised for not generating enough energy, especially in climes such as Ireland's. Yet there are currently a few hundred satellites orbiting Earth, powered by sunlight. It is realistic to design and manufacture satellites which would "beam down" energy to ground stations. But hardly any one is aware of this sort of utilisation of sunlight and such a system won't be powering Ireland in 2010.
In the past there have been people who worried that birds in flight would be fried and, if something goes wrong, that aeroplanes and cities could be destroyed. However, in reality, such a system would consist of spacecraft beaming down microwaves of a controlled strength, which would be set to approximately the same as sunlight's strength when it reaches Earth.
You may well ask, if this is possible, why isn't it being done? Unfortunately in (at least the space) industry, good, realisable proposals don't necessarily get enough backing in the short term to ensure that useful practical experiments are carried out . The idea of a reuseable launcher was around long before the US Shuttle. Though the Shuttle hasn't lived up to its early claims of very cheap launches, it is several orders of magnitude better than previous manned launchers. Admittedly the Earth-based rectifying antennas would have to be huge, perhaps 10km x 10km each, if the energy is to be transmitted at a similar power density to that of sunlight. There would be vast "sheets" of netting wire at the tops of poles (a bit like telephone wires and electricity wires today). Sunlight and rain would still get through, only slightly affected. If such antennas were aesthetically unacceptable, just as windmills are to James Kenny, they could be placed on wastelands etc.
Dr Peter Glaser, who is usually credited with developing the idea, is quoted as saying: "[Nuclear] fusion is a challenge to physicists. Power from space is a challenge to engineers, and there's a world of difference." - Yours, etc., Colin Paul Gloster,
Ashbourne,
Co Meath.