Room Heating - Gas or Electric

Hi all,

so, my garage is a bit of an everything room.

I've insulated it so it's more comfortable and spend a fair amount of time out there playing darts/making homebrew/playing piano.

My office is indoors in one of our downstairs rooms. It's ok, but noisy and feel like i'm in the middle of the house all the time so makes concentrating an issue at times.

The wife is also after a craft room so i'm thinking of moving out to the garage, let her take the office and i'll sit out there.

Only issue I have is that I haven't added heat as yet.

based on some energy calcs, I need about 2.5kW of heat, which on an electric heater is likely to be about 25p/hour. Which being as i'm going to be there all week, 8 hours a day, that's a tenner a week - PRICEY!

I'm considering
https://www.machinemart.co.uk/p/cla...6FPHoYHyr60o5qCBCFbrLUNQZVvwIcqBoCBaQQAvD_BwE

and wondering if this would be a cheaper option?
plus I could expense the gas bottles as a business expense I assume - that being said I still don't want to spend a tenner a week on heating.

I can't connect it to the central heating as the rooms don't really allow for that, and whilst it's insulated, it's probably not up to the standard required to be absolutely efficient.

 

You could fit an air con system that also heats? It would take about 800 watts to make 2.5 kw heat with the added bonus of being cool in the summer...

 

I always thoughts AC for heating was really inefficient.

learn something new!

 

I'm getting around £800 a year in grants for air source heating and my system is reported as being over 300 % efficient. You could not get grants for a single room but could still use a heat pump in the form of an aircon unit that is designed to heat without an element. Just an example, the one linked produces 2.6 KW of heat for around 750watts input power..
https://www.aircondirect.co.uk/p/87...r-with-5-meters-pipe-kit-and-5-years-warranty

There will be better and more expensive systems but I have just picked a cheap one to give you an idea. If you want a specific air to air heat pump then Panasonic, for example do a range..

https://www.aircon.panasonic.eu/GB_en/ranges/domestic/single/

 

£450 isn't too bad, and doesn't need professional installation either.... hmm that one is definitely food for thought.

 

That'.s why I picked that initially. The Panasonic units in the lower link will be slightly more efficient, especially if it is really cold but would involve a much higher initial cost

 

all things to be balanced really. I mean they suggest 11p/hr, that's already less than half the cost of an equivalent electric radiator.

11p/hr would be fine.

 

Electric heating is literally a short circuit to create heat whereas a heat pump extracts heat form outside your house and releases it inside so it is moving heat rather than making it. The outside bit gets very cold so you do need to think about certain plants etc when siting it.

 

ah this wouldn't be an issue really.
it's flat roof so could either go up there or on the external wall, which is where we keep the bins anyway so no bother there

 

There is a problem with air source heat pumps in cold weather when the outside unit can become coated in frost or ice,.

Read about it HERE

 

Mine is a Hitachi Freedom heat pump and it does the defrost cycle in literally 2 or 3 minutes. It only seems to do it if it is a little foggy though, when it is a crisp but clear night it does not frost at all. I think things have moved on with heat pumps even over the last 2 or 3 years with many manufacturers now quoting a useful heat output down to well below minus 20 degrees C and some well below minus 30!

 

A layer of ice on the evaporator (the heat exchanger in the outside unit) acts as a layer of thermal insulation and prevents any more heat being collected from the ambient air. If the ambient ( outside ) air is dry and thus no ice can form then operation at minus 20°C would be possible but at a lower COP

Two people I know have Air sourced heat pumps, both have installed alternative heating for winters when their heat pump cannot keep the house warm.

 

I think some of the earlier units did not even have a defrost function. Air source heating is very common where I live because it is rural with no mains gas and the only person in my village that had a frosting issue had a gutter downpipe dripping on the outside unit. As far as heat output goes mine has an outside temperature curve (OTC) set by its controller that is adjustable in engineers settings. I have had to reduce the output at colder temperatures because the radiators get too hot, mine is a Hitachi Yutaki S80. The mother-in-laws system (Samsung) which is a lower output still gets the rads uncomfortably hot to hold for long. I'm sure most of the mainstream manufacturers have it pretty much buttoned up with sub zero running these days.

 

11 or 12p/hr compared to 7p/hr gas which does not have to be firing the central heating of course.

 

true but would cost substantially more for me to run a radiator out there to save 4p/hr - so saves £1.80 - £2 a week.

if we said £800 to do the complete job rather than £450 of the AC, I'd have an additional cost of £350, meaning 3.5 years before it pays for itself and that's if I ran it every week (well 50 weeks)

The AC over the electric heater though is £450 instead of £100 (for the one I was looking at) so again, £350 difference but going from 22p/h - 11p/h, saving £5 a week. Meaning my £350 investment is paid for in 70 weeks which is a much more realistic timespan.