Waitakere NOW Home performance monitoring: Year two report

Andrew Pollard, Lisa French, Matthias Heinrich, Roman Jaques, John Zhao.

Reports on the second year of monitoring the Waitakere NOW Home.

Overall, the second year of occupation of the Waitakere NOW Home has seen a 15% increase in reticulated energy consumption, while the overall water use has decreased by 8%. Average temperatures in the living space remained at or above 18°C, and bedroom temperatures remained above 16°C throughout summer and winter in both years. Humidities have improved and the CO2 concentrations have decreased, due to increased ventilation.

The solar water heater converted 1880 kWh of heat from the sun into water heating in the second year of operation, contributing 45% of the energy used for water heating over the year. This reflects a cost saving of $300 per year. The Waitakere NOW Home used 82 litres per person per day (L/p/d) of reticulated water due to utilisation of a rain tank. This represents a 50% reduction in reticulated water use compared with other households in Waitakere.