On Thu, 10 Apr 2008 18:51:24 +0100, The Natural Philosopher wrote:

Cut one out of a scrapper car, along with mounts, and hook up to a
generator..you will need to run it at 3000 RPM, which is not a bad rev
range for a diesel.

3000 rpm on my diesel car engine is thrashing it a bit it's happier at
around 2250... The 3000rpm also assume direct drive and two(?) pole
alternator. You can get 4 pole which run at 1500rpm. I think the Lister
sets run at 1500rpm. You can also gear it with a box or pullys and belt.

The biggest snag with a scrapper engine will be keeping the rpm constant
(or at least within a few percent) with step changes in load.

2) how easy is it to get hold of, and run, a generator fuelled by
SOLID FUEL, e.g. coal or wood or both?

Almost impossible: you need blown boiler steam type plant.

You could use a conventional steam engine, there is a sequence of
development pictures and text of just that on the web somewhere. Generates
a reasonable amount of power as well. I suspect I may have followed a link
recently posted in uk.rec.engines.stationary. Even relatively low pressure
boilers have some hefty safety regulations to comply with though. Boilers
going bang is not good, bye bye building sort of not good...

3) how easy is it to run a generator fuelled by DIESEL? And surely if
you do, you don't have to pay petrol-station prices? Is there a legal
way to avoid paying the excise?

Buy heating oil.

Or Red diesel. Heating oil for domestic heating attract 5% VAT, I suspect
other uses should have VAT applied at 17.5%.

4) what about running an oil-fuelled generator on cheapo COOKING OIL?
Is this practicable? Is it legal?

Dunno about legal, but those sorts of oils do bad things to diesel
injectors.

Legal in a stationary engine and legal up to 2500l/rolling year in a road
vehicle without telling HMR&C. You do need to keep records though. Bear in
mind that even cheapo cooking oil is still about 80p/l. Red diesel is less
than that I think somewhere around 60p/l, might be a bit more.

It's not so much the injectors as the pump seals. Some are OK with VO
others fail in short order.

In any case whatever you use, pump any coolant or exhaust stuff into a
heat exchanger for hot water and CH usage.

I'd agree with that, dump the "waste" heat into a heat bank/store of some
sort. But look at those fuel prices, a litre of 28sec oil burnt in an hour
produces just over 10kW. So even at 100% effciency you are looking at 6 to
8p/unit. If you can get 50% you'd be doing well, 12 to 16p/unit...

--
Cheers
Dave.