On Tue, 08 Nov 2005 14:31:08 GMT, Adrian wrote:

David Bradley ) gurgled happily, sounding much
like they were saying :

Please explain further. In my book a trolleybus IS zero polluting.

Your book is - at best - skimpy.

Where does the electricity come from?

As a former CEGB / NGC employer I can answer that question in
exceptional detail. In can see where you are coming from by
suggesting that the production of electricity is sometimes less than
enviromental friendly but equally can be derived from renewable
sources such as wind power or hydro sources.

And what percentage of UK grid electricity is?

http://www.dti.gov.uk/energy/inform/...ity/dukes05_5_
6.xls

2004 -
Coal - 36.9%
Oil - 1.34%
Gas - 34.24%
Nuclear - 21.49%
Renewable Thermals - 3.34% (Burning biofuels and non-biodegradable
waste)
Other Thermals - 1.83% (Coke oven gas, Blast furnace gas, Waste products
from chemical processes)
Hydro - Natural Flow - 0.5%
Hydro - Pumped Storage - 0.27%
Other Non-Thermal - 0.2% (Wind, Wave, Solar)

So somewhere in the region of sod all. Or, to put a number on it,
renewables make 4.31% of the UK's electricity.

A lot better than I expected, I will admit. But still not much.
Especially as any ramp-up in demand will be met by the non-renewables,
as the renewables are stretched to provide the current amount.

The power might even have been provided from another country but
however it was produced, and where ever it originated from, the
product does not come with any kind of labelling for your average user
to be able to determine its source.

Indeed. So it's not quite right to say it's "zero-polluting", is it?

The right combination of circumstances can therefore have a trolleybus
operating on a fuel that can be considered to be entirely zero
polluting and to suggest that can't happen is bunkum.

Indeed.

However, to suggest that it's *likely* to happen is equally bunkum.

In any event I would certainly prefer a trolleybus service running
past my front, especially at night, rather than the cleanest of
diesel buses.

Ah, the "I don't live next door to a powerstation, so they don't
matter" NIMBY line.

Obviously I have preferences were I wish to live [who doesn't?], but then you
are suggesting that the air is less pure around a power station than at the
kerb side in west London. Catch up on the facts and you will find this not so,
and indeed the air quality is at dangerous levels over in east London,
especially around the Ilford area!

Yet again I have to wearily point out the difference between the gross
pollution, the point of delivery from diesel buses (in addition to the wider
global pollution from the oil industry) and the admitted element of global
pollution from power stations. However, I would, however, draw your attention
to url http://www.tfwl.org.uk/media/drax.jpg where I have posted a media
cutting from the Financial Mail regarding the base load coal fired power
station (or rather two stations, with space for a future third, grouped around
a single 3-flue chimney) at Drax, This is said to be one of the cleanest coal
fired power stations in the UK. It didn't start out that way until the
Scandinavians blamed British power station gases, particularly the main
generating area in the Humber basin (including Drax) for acid rain carried on
prevailing SW winds denuding their forests and killing their river fish.

Considerable sums have been spent in cleaning up the flue gases from all power
stations in recent years, and while pollution levels are not at zero, the
small amount of damage done to the environment it is at least a considerable
distance away from areas where population congregates.

Trolleybus services passing my front door would be quiet and using a power
source that could be entirely zero polluting or at the very worst much kinder
to the environment than a diesel bus ever could be. If that makes me a NIMBY
then so be it. Trolleybuses are the least polluting transit vehicle there is;
maybe not exactly at zero but close enough to say so.

David Bradley