The first post

We've teetered on the brink of installing a new heating system almost since we moved into the house but hadn't taken the plunge until now. We inherited a 30+ year old oil boiler with the house. It's been pretty reliable but with the cost of oil having gone up so much (I think it was about 45p per litre last time we bought some) and the boiler probably being pretty inefficient we needed to do something about it.

Our old boiler

The challenge is that the house is quite big, stone built and short of ripping the plaster of the walls, very difficult to insulate. It also has loft-rooms, so insulating the roof is a bit tricky too. We've had all sorts of advice over the years, from those who say that retro-fitting a heat-pump to a house like this will never work because the heat-losses will be too great, to those who say it will work fine.

We currently don't heat the house particularly well, largely because I'm a stingy miser and don't like paying for the oil but, even so, our oil bills were probably somewhere around £1,500 to £2,000 last year. As well as the existing boilder we have two wood-burning stoves, one in the kitchen and one in the living room. We fuel these entirely from wood from trees that conveniently fall down from time-to-time in the garden when there's a strong wind.
In the past year, we've started looking more seriously at replacing our heating system. We've looked at both heat pumps and wood pellet boilers. The wood pellets had some major advantages -

• very low carbon emissions
• a similar kind of heat output to an oil boiler so very much a straight replacement

The downsides with the wood-pellets were largely to do with space: the unit itself is big and we couldn't work out how to fit it into the space the current boiler occupies plus we would have to find space for storage of wood pellets. There was also the issue of having to get the wood pellets from the storage to the hopper of the boiler. Either this would have to be done by hand or an auger would have to be fitted which would have significnatly to the cost.
The other factor in our thinking is that we have the wood-burning stoves and we don't actually like our house to be very warm (probably no more than 15-18 degrees).
For these reasons, we have eventually gone for a 17kW ground-source heat pump. We're aware that this is a bit of a risk given the type of house we live in.
The aim is to get the heat pump in over the next month - hopefully before Winter really sets in. The heat-pump is a NIBE, supplied by EcoLiving. The first step of the installation is going to be drilling two 150m boreholes which should be starting early next week.