On 03/11/2011 10:17, The Natural Philosopher wrote:
Roger Chapman wrote:
On 31/10/2011 19:46, John Rumm wrote:
On 31/10/2011 19:24, harry wrote:

Mind you, £0.21/Kwh would still give a better return than money in the
bank these days.
I wonder what percentage of the national load it provides on a sunny
day?
I have done 2747Kwh to date.

It hardly matters, it will need a proper power station sat there in hot
reserve anyway, so its real contribution is of little value.

Nonsense.

Unlike windmills the major contribution of PV panels is reducing
demand on the grid and with a multitude of individual houses any
variation in demand/output will be statistically easy to determine and
any variability will be small in relation to the other factors that
the grid has to take into account.

You really haven't a clue have you

Projecting your own failings on others again as usual.

The major contribution of *any* power station is reducing demand on the
grid to exactly zero, overall.

Its about time you took the trouble to formulate your sentences so they
mean what you think they mean. The only way to reduce the demand on the
grid to zero is to turn absolutely everything off.

PV panels are just a massively expensive and inefficient and
uncontrollable way to do it.

I don't know what the exact proportion is but even windmills don't
need 100% of hot reserve. PV panels shouldn't need very much (or even
any) even if every house in the land was so equipped.


At night PV panels need 100% reserve. They produce nothing. On a grey
day in winter they produce so near nothing as to be irrelevant,

They have in fact a worse variability than windmills. which seldom got
to nothing everywhere. PV does it every might,.

The output of a multitude of small PV arrays is predictable to a very
large degree and relatively consistent as well. It reduces domestic
demand at a time when total demand is high and requires no hot reserve.
That PV panels produce nothing during the hours of darkness is of little
consequence because of the consistency of the output. Windmills OTOH are
as likely as not to be generating at times of lowest demand and failing
to produce even as much as PV arrays when demand is at its strongest.

--
Roger Chapman