3 ms·
Yes, but if the electricity is made from gas, then 300% efficiency of heat pump is better than 98% efficient heat furnace only if generation efficiency is at le
by xyzzyz 4y ago
Yes, but if the electricity is made from gas, then 300% efficiency of heat pump is better than 98% efficient heat furnace only if generation efficiency is at least 33%.
Heat pumps are pretty great, but as of today, they are by no means necessarily more efficient than burning gas directly for heat, at least when it comes to GHG emissions. In fact, in very cold climates where air temperature is below freezing most of the time, air-source heat pumps are highly unlikely to be more efficient than just burning gas, unless we move wholesale to nuclear for electricity (solar won’t help you during winter, and wind is too fickle to solely depend on).
- bryanlarsen 4y ago> only if generation efficiency is at least 33%. the efficiency of a combined cycle gas generator is usually 50-60%.
- xyzzyz 4y agoThen it depends on what portion of the electricity mix is CCG instead of simple gas turbines or coal, what’s the actual efficiency of heat pump (you won’t get 300% when it’s subzero temperature) etc. Point is, air source heat pumps are really not much, or even necessarily at all more efficient than just burning gas directly at home, it all depends.
- bryanlarsen 4y agoat >50% efficiency, the heat pump heat factor has to drop below 2. On a modern heat pump that's about -25C or so. I don't think it gets that cold in Germany.