Re: Wind Power

["Mark Harrison (Groups)" <mph@xxxxxxxxxxxxxxx>]

>If there are any electricians on list could they explain how this could
work... I simply don;t get it ...
>
>
>
Not an electrician, but did work with a team from BP Solar a few years
ago on the installation of Solar energy in petrol stations, so learnt a
fair bit about this.

>The only thing I can think of is a ring main is like a big water pipe -
it has finite capacity so if you add water from somewhere else it gets full
quicker...What I don;t get is that your power co will be already meeting
your capacity so adding more 'water' would achieve nothing...
>
>
That's an OK metaphor, so let's see if I can stretch it far enough :-)

The water pipe (grid) has a FLOW capacity, not a storage capacity - it
doesn't really store any water (electricity)... however, at various
points in the water pipe network are a series of feeder pipes from power
stations. If the distribution pipe looks as if it might run dry, they
start adding water more quickly (by firing up additional power stations,
or bits of power stations).

This isn't instantaneous - turning on and off a traditional power
station is, well, slow. In fact, the way that storage IS provided is
quite clever. The big hydro-electric station(s?) use spare electricity
in the quiet periods to pump water uphill. Then, when the demand for
electricity is high (say, at the end of Eastenders when several million
people turn on a kettle), they run the water back downhill, spinning
turbines, and generating extra power for a while. This is, in absolute
energy terms, wildly inefficient. They use a lot MORE electricity
getting the water up than it generates on the way back down. However, it
effectively manages to use up spare electricity that would otherwise,
literally go to waste (in the form of heat.)

The conceptual trouble with microgeneration, and its impact on the grid
is a quantisation one - the unit of supply to the grid is basically the
power station. So the fact that you, on your own, get a micro-generator
(whether wind, solar, water, or geothermal) won't actually affect the
amount of power generated in the slightest, except for the .0001% of the
time when you tip the difference between an extra power station being on
or not....

... however, if, say, 10,000 people got these, it would make a
difference ...

Consider the way that power is priced - it's a scale efficiency thing.
You pay for what you use, not on the basis of how much it would cost for
you to set up an equivalent generating capability, but on the basis of
everyone sharing in amortising the massive capital costs of large
plants. Likewise, if everyone saves a bit of energy (either by not using
it, or generating locally), the net effect is huge.

M.