Heaven in the Hills takes total responsibility for the production of  its own electricity and is not connected to the electrical grid.  The system is based on renewable energy sourced from solar and wind generation.  Energy is stored in 48 gel cell batteries and converted to 240 volts by an inverter.  This enables the use of conventional appliances throughout the property.  Gas and wood are used for heating.  However, behind the scenes much thought and planning has resulted in efficient usage of power especially in areas such as gravity fed water, low wattage light bulbs and the above design features, maximising light and temperature control.