Hi Richard – that is a good question. So in the first instance, if you have a south facing roof then solar PV is a great idea provided your roof is in good shape and can support the panels. A 3.5kw system will produce an annual return of about £800 when you take into account the energy savings and the feed in tariff. The best thing here is to get someone to assess the roof (size and strength) and see how many panels you could fit on it first.
Once you are producing electricity you can start considering a heating system. So biomass are great EXCEPT you need to feed them fuel. This becomes a pain if you go on holiday during the winter since you will need someone to come in and fire up the heating. However if you can get over this, they produce nice hot water and obviously you get paid the RHI which depending on the size of the property can be rather generous.
If capital is not an issue and you are going to be in the property for 10 years or so, the best way to heat the home would be a ground source heat pump. Despite using electricity, they produce heat efficiently, producing 4.5 units of useful heat for every one unit of electricity consumed (so 450% efficient if you will compared to a brand new gas boiler that is only 90% efficient). These are fantastic, and the efficiency doesn’t drop during the winter which is important seeing as this is when heat demand is at its highest. If you are producing electricity from solar too – then obviously this will help cover some of the running costs too, hence we are strong advocates of setting them up together. It is worth pointing out though that heat pumps produce hot water at lower temperatures than conventional boilers so they need to be installed on really well insulated homes.
Hopefully that is a decent starter for 10, but i am sure other community members will jump in and have their say!