Ground Source Heat Pumps
Ground source heat pumps are another form of extracting natural free energy that can be used to warm your home and reduce your energy costs. Pipes buried a few feet under your garden or lawn can draw the heat from the ground. A few feet below the surface the ground temperature is more stable than on the surface, so while you may have a layer of snow on your lawn, underneath the ground temperature is fairly constant. That ground heat can be extracted easily for your home use.
Ideally installation should be done with a new build as excavation work is required and may require some form of machinery heavier than a garden spade. Coiled pipes are laid in trenches under you garden covering as much area as possible to maximize the heat transfer, smaller gardens may require laying the piping vertically to gain as much contact area as possible, this would involve deeper digging than a larger lawn where the coils can be laid flat.
Once that is complete the trenches are refilled and your garden is restored back to its normal appearance. Water, with some antifreeze, is then circulated around the pipes returning warmer than when it entered full of free heat.
Now what can you do with this heat? Underfloor heating, where another layer of piping is laid under your floor to provide warmth all year round as well keeping your energy costs down.
A small amount of electricity is needed to run the heat pumps and economically this could be acquired from solar power via your rooftop solar panels.
Costs and savings.
These will ultimately depend on your current heating system and energy use. For the greenies a reduction of 1.5 to 2 tonnes of CO2 emissions per year is possible and none of us really like that stuff hanging around in the air. Installation could cost between $5000 to $10000 with annual savings of $1000 or more on your heating bills possible. Like solar heating, the actual amount of costs and savings depends on your current forms of heating and locality of your home. For new builds the installation costs can be much lower as the cost can be absorbed by the construction process itself.
Further energy savings which you should already have implemented, like insulation your home and draught proofing, can further reduce your energy dependence and costs. As ultimately in the future the price of supplied energy will rise and the time to start saving is now. Ground source hear pumps can be a worthwhile investment in both your pocked and the environment. You can be a little bit greener without eating lentils and sleeping in a tent.