Replacing night storage with Air Source / Ground Source / Other - Brain frazzled!

Abblybee

Hi everyone, 
Hoping here for a bit of guidance. We're just about to move into a new average size 3 bed home. It's a 1850s stone cottage with a 1960s extension making up about 40% of the property. Currently it's heated with old night storage heaters and they use an immersion tank for hot water. 
As you can imagine the efficiency isn't great (particularly in the old parts of the house). I'm planning to line the external walls, but my main concern is to change the heating system into something more efficient. It would be great if I can use the RHI to do this. One of the considerations I also have is that I work from home so the house needs to be heated during the day.
The options I've seen are the following (+ my current thoughts): 
1) Replace with newer electric rads (eg Fischer): I've seen elsewhere on this forum that these are more efficient when working, but ultimately this almost like for like alternative may not be best as they'll be in use during the day. 
2) Air source to water: My understanding is that this will be pretty efficient in terms of providing all day heat. Downside would be that I'd need to have the water distribution system installed as well which would add to cost. Can get help with the RHI. 
3) Air to air: My understanding is that this basically acts like an aircon and can provide constant heat. Seems RHI can't help me with this + it doesn't provide a hot water solution. 
4) Ground source: I'd consider this as an alternative to Air to Water although the upfront cost seems to be more. Not sure what the benefits would be; I currently understand less noise, maintenance but not sure about running costs. 

I'm somewhat befuddled with these various options so it'd be great if anyone has any comments or advice on the above (or anything else I'm missing). I have spoken to a few companies but they obviously have a vested interest in selling their own solution. 
Thanks in advance!

Gerry1

Abblybee said:

1) Replace with newer electric rads (eg Fischer): I've seen elsewhere on this forum that these are more efficient when working

Noooooooo  ! 71 pages worth can't be wrong.  Why on earth would you want to pay 15p per kWh at day rates rather than 8p or whatever your E7 night rate is?

Gerry1

Assuming it's impossible to get mains gas, oil would probably be your best bet. But predicting the future is always risky.

matelodave

You need to do your own homework. to decide what the heatlosses in your house will be, and then see ho to improve them to the point where you can evaluate heating systems.
Dunno where you've read about Fischer or any other heater of that type being a good idea, they are only marginally better than physically burning £20 notes in the fireplace.

Putting in a new heating system, especially into an old place needs a lot of investigation which means you need a lot of quotations from different suppliers of different technologies. All have advantages and disadvantages and there is not a one size fits all solution so you need to be able to evaluate how any type of heating will suit your life style, pocket and will also be determined by how long you expect to stay there.
There's no point in spending £20k and then selling up in five years time unless you can recover a fair proportion of the outlay, either in reduced fuel costs or added value when you come to sell. Running costs are a consideration, mains gas is cheapest, oil is next, a properly designed heatpump system is probably next, then LPG, then storage heaters - dont even consider panel heaters/radiator like Fischer, Rointe etc or an electric boiler with radiators

Consider RHI as a bonus rather than a reason for doing it because it will still take 7 years or so before you get it all.

We all have our opinions about what is best.

I fitted an air-water heat pump but I would have gone for mains gas had it been available (and I'd probably still swap it if gas did become available) Our alternatives were then for oil, lpg or biomass or even replace the rusty festering storage heaters. I didn't want either a gas or oil tank in the garden, nor did we have space to store a couple of tons of wood pellets and as we had the advantage of doing a complete refurb, we also installed underfloor heating as well.
We.ve had it over ten years, we got £5k over 7 years towards the cost and I reckon it's paid for itself in reasonable energy bills over that period. However it suits our lifestyle as we are at home all day everyday, it would not be as suitable if we only wanted to heat the house for an hour or so on the mornings and evenings as it takes far to long to reheat the place.

The cheapest and least disruptive to install is storage heaters, anything else will involve plumbing, either radiators, underfloor or even refrigerant piping for an air-air system so that's got to be taken into account.

The size of rads and plumbing will depend on the sort of heat source. Heatpumps (either air source or ground source) need larger rads than either oil or lpg boilers. Oil & LPG is more responsive than a heatpump and therefore are more suited to an on/off regime, but need a big tank outside. Ground source needs a big plot of land or extremely (100m) deep bore holes to install the ground loops.

Abblybee

Thanks matelodave, that's great advice. 

Putting in a new heating system, especially into an old place needs a lot of investigation which means you need a lot of quotations from different suppliers of different technologies. All have advantages and disadvantages and there is not a one size fits all solution so you need to be able to evaluate how any type of heating will suit your life style, pocket and will also be determined by how long you expect to stay there.
There's no point in spending £20k and then selling up in five years time unless you can recover a fair proportion of the outlay, either in reduced fuel costs or added value when you come to sell. Running costs are a consideration, mains gas is cheapest, oil is next, a properly designed heatpump system is probably next, then LPG, then storage heaters - dont even consider panel heaters/radiator like Fischer, Rointe etc or an electric boiler with radiators

We're in a similar position to what you had because we cannot access mains gas. Also, like you, we're planning to stay for a long time so the RHI seems attractive if we can recoup some, although I understand it shouldn't be the primary reason. 

Because the main part of the house is stone I'll be drylining and insulating the lower walls and will improve insulation where possible, although I imagine there'll always be some limitations due to the original materials. Air to Water seems attractive as it'll solve hot water too, although there is the disruption of fitting the pipework. That said, we do need to do a lot of work internally anyway.