It’s too good to be true isn’t it? Energy from the ground? Either that, or it’s not something you’d even consider if you didn’t live somewhere like Iceland, with an active volcanic system that can easily be tapped for energy.
But, believe it or not, energy can be drawn from the ground, even in cold climates like the UK, and it’s very effective as well.
So as part of our energy series, we are going to investigate this fascinating subject.
OK, so what do we mean by getting energy ‘from the ground’. Well, the answer is quite simple.
You see, on the surface, we live in a world of varying temperatures. Each day is a different temperature and as the seasons change, so does the temperature.
But underground, things are not quite the same. You don’t need to go far down before you find that the temperature stabilises, and becomes quite steady. This is something that we can take advantage of.
By arranging a system of pipes under the ground, fluid can be pumped through them and heat extracted simply by the heating effect that the sub soil has on this fluid.
The principle is exactly the same as what’s happening in your kitchen refrigerator. Heat is taken from one place and moved to another.
This is the basis of what’s called heat pump.
Ground Source Heat Pumps Basics
These devices are called Ground Source Heat Pumps, or GSHPs. By pumping a mixture of water and anti-freeze through a system of pipes laid in your garden.
This loop of pipe in the ground is called a ground loop. The size of the pipe depends on the size of your home and your heating requirements.
The water and antifreeze mixture is pumped through this and absorbs heat from the ground.
Once the mixture has travelled through the loop and has heated up, it is passed through a compressor and can then be used to heat water for your home.
There are some basic requirements that a ground source heat pump needs.
The first of these requirements is space for the ground loop. You’ll need to have a garden big enough to install a long, winding loop of pipe several feet beneath the surface.
The size of the loop is going to depend on your heating requirements, but even the smallest loops are of considerable size.
An alternative is digging a borehole. This is a more expensive option, but requires a lot less space on the surface. It can also extract more heat from lower down in the ground, so you do gain some benefit from the increased initial cost of installation.
You are also going to have some additional equipment above ground to cope with the heat exchange. A compressor and heat exchanger will need to be installed in your home, and these will also take up some space.
GSHPs come with a variety of benefits.
First off, they are very efficient, and will reduce your energy bill considerably. It will take a little time to offset the initial cost of installation however.
GSHPs can be used to heat your home and your hot water, so one system can be used for all your heating requirements. In addition, you’ll never need fuel deliveries.
You may find that in winter, you’ll have your heating on constantly, but radiators will feel cooler to the touch. The system is very low maintenance.