Zero Tolerance wrote:
On Tue, 15 Sep 2009 09:39:13 +0100, "Norman Wells"
wrote:

However, he ignores the fact that he's also losing 45 watts of heat.
To keep his house at exactly the same temperature, an extra 45 watts
of heat need to be pumped out by whatever heating system he has, for
as much of the year as he needs any heating at all. Admittedly,
that may be a bit cheaper if it's gas-fired, but it's still the same
amount of energy, so it's unlikely to have a huge impact on climate
change.

This is an old (and thoroughly discredited) logical error.

Who has 'discredited' it, and where?

Saving 45
watts of energy is not the same as saving 45 watts of heat. For a
start, most of that energy is expended in doing the 'work' - e.g.
lighting lights, spinning discs, and so on. Any excess heat generated
after that (unnecessary) work is done is minimal.

By your logic, if I leave a Sky+ box on standby, then the 20 watts it
spends on spinning the hard disc is converted into 20 watts of heat.

You're following me well so far.

If that were true, it would turn Sky+ into a free energy machine -
which is impossible - breaking every scientific law there is.

Why do you think it takes 20 watts of energy to keep a spinning disc
spinning?


Your 45 watts of wasted energy probably results in (I'm guessing here)
maybe 2 watts of heat.

You never studied any science at school, did you?

If you did, you either never got as far as the law of conservation of
energy, or never understood it if you did.

Whatever heating system you have is going to be
a FAR more efficient way of generating an equivalent amount of heat.
And considerably cheaper too.

It will be somewhat more efficient, and it will be somewhat cheaper as long
as it's not electric. There are some savings to be made therefore, but not
as much as greeny-weenies think.