Welcome to European Tribune. It's gone a bit quiet around here these days, but it's still going.
Actually, you have the problem of COP<1 only with the "cheap" (that is 5000 €) heat pumps fitted on the balcony, and which try to exchange heat with the atmosphere like an air conditionner. They practically stop working at 0°C because of frost on the exchangers.
"Real" heat pumps take the heat from 1.5 m underground, where it's 10°C almost all year long, with burried pipes (that's where you need a lawn and big work $$$). You may need additional fuel heating a few days/weeks per winter if you are in a really cold area where the ground freezes in the winter (like: there is 20" of snow on you lawn for 2 months every winter...)
There is still a variant to fix this problem: the heat well heat pump, with a few 50-100m wells which get the heat from the waterbed, which never freezes in any  place that actually has grid power (Siberia is a special case...). And you actually need less lawn area to conceal those wells, but they're even more expensive to drill (expect 20-30k€ for a mid sized house - you may have a tax rebate on this in some countries).

by Pierre on Mon Jul 10th, 2006 at 11:53:24 AM EST
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