[ExI] pentagon wants orbiting solar power stations

[BillK]

On 10/13/07, Eugen Leitl <eugen at leitl.org> wrote:
>
> Spike, you took his numbers at face value. The numbers are complete bogus.
>


The numbers are issued by the Royal Institute of Chartered Surveyors.
Every house that is bought and sold in the UK is surveyed and reported
on by their members. I doubt that they intend to ruin their reputation
by producing rubbish figures.

Their spreadsheet says a typical price for a home solar water heater,
Thermal Panels, (flat plate type), professionally installed, would be
£5,000. A quick Google of UK prices indicates that this is not a
ridiculous figure.

They estimate an energy saving of £24 per year. This is where the
finger in the air assumptions enter. Water heating is estimated at 25%
to 30% of the total home energy bill. Solar panels may save up to 50%
of this, depending on latitude, shade, building alignment, etc. And a
solar system uses mains electricity to drive the pumps. There are
actually about a dozen variables, with assumptions, that should be
included, so really it is anybody's guess. (And fuel prices in the UK
are probably different to Germany).

But so far, in the UK, it is not at all obvious that everyone should
rush out and get solar water heating installed. Wait and see is safer
at present.

BillK