It is a bit misleading. Insulation is the main cause of lower energy bills. Then, once your losses are at a minimum you just need a bit of a kick to keep the wa

It is a bit misleading. Insulation is the main cause of lower energy bills. Then, once your losses are at a minimum you just need a bit of a kick to keep the warmth. Any system will do once your energy losses are miniscule, e.g. think of the passive homes.