A heated water service with its distribution system and components must use energy and water efficiently, in a way suited to the service and its use, the building's location, the location of the service and the energy or water source; net energy from renewable sources may count as free energy. Deemed-to-Satisfy B2D2 for a new Class 1 or Class 10 building: a solar or heat pump water heater meeting minimum Small-scale Technology Certificate counts by bedrooms and year (or minimum energy savings of 40 or 60 per cent under AS/NZS 4234), a gas water heater rated at least 5 Stars under AS 4552, an electric resistance heater of 50 litres or less only in limited cases (one-bedroom building, one resistance heater beside a compliant heater, or a low-emission electricity supply), or a wood fired thermosiphon or direct fired heater to AS/NZS 3500.4. It does not apply where the energy provisions of Volume Two are met by house energy rating software. New South Wales and Queensland leave the clause to BASIX or blank.
The graph holds this control, the 0 it maps to, and the evidence behind each claim, over MCP and REST.