Ground Sourced Heat Pumps

Did you know you can you use your garden to heat your home?

Many of us use reverse cycle air conditioners to heat and cool their homes.

These unit are are ‘Air Sourced’ heat pump that:

  • Extracts heat from the air and uses it to heat your home; or
  • Extracts heat from the air in your house and disposes of the heat outside.

When the outside air gets very cold the air sourced heat pump becomes less efficient.

An Alternative – Ground Sourced

These are sometimes incorrectly called geothermal heat pumps but they don’t use energy from hot deep rock strata.

They take advantage of the fact that the soil at a depth of around 1m is generally at a temperature around 15 degrees all the year round.

By pumping water around a network of pipes under your garden they extract this heat.

In cold conditions this water being warmer can give up more heat than the air for use in the home.

Are ground sourced heat pumps worth it?

Ground source heat pumps can be a bit more efficient than air source, but not by a whole lot in most Australian locations.

The problem is they are very expensive to install as they involve burying long pipelines deep below your garden.

The units being less common are also more expensive than the standard units you may be familiar with.

In my opinion the additional expense is just not worth it for the few days when the temperature drops below zero.

You would be better to put some additional solar panels on the roof to cover any additional power needed for an air sourced unit.