"RJH" wrote in message
...
When you do teh sums ist pretty celar waht is genuine energu savings
(insulation, heat pumps, running the house a bit cooler) and what is
utter ******** virtue signalling designed to sell product (kettles and
hoovers, diesel cars etc etc).


How can you expect anybody to take you seriously with that type of
reasoning? Any energy saving is a saving. Wasting energy is wasting
energy. Not difficult.

Yes, but you concentrate most effort on appliances that use most energy.
Better insulation etc is going to save more energy per household than
heating less water in the kettle or using energy-saving bulbs in a house. In
an office where there are lots of lights which are left on all the working
day, the savings of using fluorescent (or LED) over tungsten are more
significant, but in a house where lights are usually only on for a few hours
in the evening and early morning, it's less signifiant.

But I agree, every little helps - a little!

I bought my diesel car as much for the extra torque and therefore less need
to change down as far for every little gradient or junction, as for the
saving on fuel consumption. Ironically, my wife's diesel Honda is much more
like a petrol: I forever forget that it needs one or maybe two gears lower
than my Pug when going round a junction or as a downhill road starts to rise
again. Heavier vehicle, engine probably depends more on its turbo - it's
only a 1.6 but a much bigger car than mine. I reckon the turbo sometimes
runs out of puff as you slow down for a junction and then can't get enough
air in the cylinders as you start to call for power.

My present 1.6 HDi Peugeot 308 has averaged about 54 mpg since I got it at
18,000 miles (it's now done 180,000) and the last petrol car that I had was
a 1993 1.8 Golf which averaged 37 mpg. OK, so that was old technology:
better to compare the Golf with the 1.9 HDi Peugeot 306 that I bought
immediately after the Golf (in 1997) which averaged 47 mpg.

So a significant saving: 37 compared with 47. However you have to take into
account that diesel is now *more* expensive than petrol, so cost per mile is
a better indicator. I can remember in the mid 70s, when the only diesel cars
were taxis with tractor-like engines, diesel was about half the cost of
petrol, partly because it was taxed at a lower rate. Then the tax rate
became the same, and diesel rose to about 90% of petrol price, and now the
cost of the raw diesel is actually more than for petrol, despite the much
greater demand nowadays than in the 70s when only lorries and taxis used it.