Air heating does not require drilling or hoses being laid, which makes it a great solution when land is limited and a partial upgrade is being considered – heat pump + current system.
Geothermal energy is a stable heat source, where one or more boreholes are drilled in the ground. This method is unobtrusive for the garden.
A ground source system means that a long looping hose is buried about a meter below your property. A large area of the property will need to be dug up, putting it temporarily out of use.