I pay 8.6p/kW on electric and a 15kg butane Calor gas refill is around £20.

I don’t have central heating.

I’ve heard 15kg of gas is good for 200kW but that puts the cost at 10p/kW + the hassle of refilling the thing. Any one got figures on how many kW a kg of gas is good for?
Guys, just blurting out gas is cheaper doesn’t help. From what I’ve heard 1kW of Butane Gas ends up costing 10p while 1kW of electric costs 8.6p. So going by that electric is cheaper. Can anyone substantiate that?
I appreciate the answers guys, but they don’t quite address my question. 1kW of heat energy is the same whatever you’re using. Just like 1kg of concrete weights the same as 1kg of cotton.

So it doesn’t matter if a gas heater on 1 or 3kW, the bottle has a finite amount of kW it can provide. Obviously 3kW 24/7 is going to last a third of 1kW 24/7.

The question is, can a gas heater be cheaper to run than electric by providing enough total heat energy (kW) per 15kg butane cylinder?

It depends a lot on how powerful your electric heater is – is it a 1kw, 3kw etc. If its more than a 1kw heater and you have to run it on a high setting to provided sufficient heat then you will have to multiply your electric costs.

I find that a Calor Gas heater throws heat out quicker, therefore can be turned down sooner. The biggest disadvantage is the moisture they produce and as you say the need to get refills, although this does mean you pay as you use so no bills running up. It is also more portable, you dont have to have a handy socket or wires running over the floor.

I would not consider using Calor for whole house heating (due to the moisture problem)

Could you use a combination – Calor to give a quick blast and get the room warm and then electric to keep it ticking over.

If you do use Calor – get a second bottle and have it filled and ready. Nothing worse than running out of Calor at 9pm on a Saturday night and occassionally suppliers run out of supplys.