Do the panels work in tandem with existing central heating systems? How does it work with things like an AGA?
To be rid of fossil fuel boilers we have to focus on an all-electric solution.
We moved in with an AGA, and although it’s ok for certain things, we are not massively keen on the fact that it’s on in the summer, burning fuel and overheating the kitchen.
Assuming the central heating and AGA is oil-fueled, and the aim is to ditch oil and go electric. With solar PV we are producing electric power, not heat, so any use of pumps etc. can be powered by PV – and of course lighting, computers, chargers, washing machines etc.
Firstly regarding the AGA. We have a number of customers who have either converted the oil AGA to electric, ditched it completely or bought a brand new electric version – and there are other makes out there. Originally these type of cooking devices were great for windy, leaky homes and when oil was cheap, and no-one realised the full ramifications of burning oil. Today when homes have great insulation, double-glazing and better draught-proofing kitchens can overheat. With an electric version, it's easy to control so can be easily switched on and off by electronics. If one has an electric AGA, the consumption can be offset by PV.
Anything oil-powered cannot so easily be offset by solar except in the role of hot water heating. Solar tubes can pre-heat hot water. In fact, in some cases, the same solar thermal system that is heating a pool can heat the hot water. In some cases, solar thermal can contribute to heating. Next, enter heat pumps which come in two main varieties, air and ground source. You are probably aware of the role of air-conditioning units, which take the heat from in a warm building and exit it to the outside with air and fan heat exchangers. Air Source Heat Pumps do the same, but extract heat from the air and put it inside the home heating radiators or underfloor heating or both. They can also heat the hot water. So, in this case, solar PV can help power central heating heat pumps directly, and make particular inroads in those shoulder months.