Heatpumps are less efficient when it's very cold out. It's only really the ground sourced ones which are very efficient.
But 1kw is still 1kw
Last edited:
Heater for the car.
- Thread starter DEL 707
- Start date
Heatpumps are less efficient when it's very cold out. It's only really the ground sourced ones which are very efficient.
But 1kw is still 1kw
Commissario
or some of those wheatgerm/rice thingies you bung in the microwave for a minute.
That's basically what I used to do when my dad had eye appointments at the hospital, as I never knew how long they'd be* it wasn't worth going home (30+ minutes each way), so I'd wrap up warm in the winter with some gloves, hat and a travel blanket and if need be run the engine with the heater on full for about 10-15 minutes every now and then.This. If your lunch is an hour long then 15 minutes running should keep you going. Just don't watch your average MPG drain away as you look at it
*He was in for less than 45 minutes one time and came out having had an unplanned minor eye op with a laser, another time it was a routine appointment and about halfway between him doing the basic checks and the consultant there was an emergency that pulled the the consultants away to do a major emergency operation, that time was about 6 hours, with snow.
Well 1kW heater making 1kW of heat is different to a heat pump turning 1kW into 1.5 - 2.5kW of heat...Heatpumps are less efficient when it's very cold out. It's only really the ground sourced ones which are very efficient.
But 1kw is still 1kw
Soldato
Heatpumps are less efficient when it's very cold out. It's only really the ground sourced ones which are very efficient.
But 1kw is still 1kw
The whole point of a heatpump is that 1kw is not 1kw, even on the coldest UK day you'll still be getting around 2.5kw of heat out for the 1kw you put in.
An EV might only be taking a few hundred watts to keep the cabin 'topped up' with heat, they really are very efficient now.
Associate
We have a canteen at work, it has a radiator.
Which is lucky, because we'll need a lot of heat to unfreeze hell the day Nasher says anything positive about an EV
You'll need at least 300 watt to make a difference, 600-900 watt to make it comfortable - the ones you plug into 12V outlet are usually 150 watt max and usually 80-100 watt if they actually work without constantly blowing the fuse and little use for anything other than warming your hands up or aiding a little with defogging.
It isn't good to deep cycle car batteries so assuming your car battery is in a decent state of health and charge you won't want to be running something in the 100s of watts to a kilowatt for more than about 30 minutes if you are doing it regularly and you care about battery health and likely won't get more than 1-2 hours before you risk depleting the battery and can't start the engine, worse if the battery has seen a few years of use.
Not a big fan of them but heated seats are usually in the 40-60 watt range and probably more effective in this situation - if your car doesn't have them you can get plug in ones you can put over the existing seat (just don't leave them running when you get out the car and come back to a dead battery).
It isn't good to deep cycle car batteries so assuming your car battery is in a decent state of health and charge you won't want to be running something in the 100s of watts to a kilowatt for more than about 30 minutes if you are doing it regularly and you care about battery health and likely won't get more than 1-2 hours before you risk depleting the battery and can't start the engine, worse if the battery has seen a few years of use.
Not a big fan of them but heated seats are usually in the 40-60 watt range and probably more effective in this situation - if your car doesn't have them you can get plug in ones you can put over the existing seat (just don't leave them running when you get out the car and come back to a dead battery).
Last edited:
Soldato
I don't think running the engine is particularly environmentally friendly.
Underboss
just turn on the engine, how hard is that? 
Makita make heated jackets which use their batteries; that's gotta be worth a look. The general idea is to heat the person not the space; and with a separate battery you can be sure you'll not be running your car battery down on the heater (of course you might still be using the stereo / etc)
Underboss
you could always get a power station and plug the heater into that