wrote in message
oups.com...


Alan wrote:
"John Rumm" wrote in message
...
Grunff wrote:

24.5p a few weeks ago.

Oil is much, much cheaper than electricity. Don't even consider
electric
heating if you have oil.

About the only way to get a sensible price using leccky is with a heat
pump aircon unit. That way you can dump 4kW of heat into the room for
1kW worth of electricity.


Why is this? I had assumed they'd be less efficent at heating than a
traditional heating element.

Because the 1KW is used to pump 3kw of heat from elsewhere that's
already there(like outside air). The 1 kw heat from the compressor is
added to this so you get 4kw.
It's a refrigerator back to front, with a fan. You could say it's
cooling the outside air and transferring the heat to inside. I gather
some heat pumps are even more efficient than just 300%.
In some places they have pipes under their garden which collect heat
from the ground instead of the air, but britain is a bit ecologically
backward, so most people haven't even heard of "ground source heating"
and the efficiency of heat pumps(1,800,000 gooogle hits) :


http://www.google.com/search?hl=en&q...oogle+S earch

M.K.


Alan.


Thanks, I often wondered about the efficiency of running A/C heat pump
systems all year to heat and cool a building as required.
I guess by the same token, the cooling process is reasonably energy
efficient also.

Alan.