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The BRANZ HEEP Energy and Temperature Data Information tool has retired.

If you have any queries with regards to HEEP or the HEEP Energy and Temperature Data Information Tool, please contact us



The Household Energy End-Use Project (HEEP) was a long-term study with the objective to measure and model the way energy is used in New Zealand households.

The project was funded continuously by the Building Research Levy and at various times in various ratios by FRST, EECA and others and was the most thorough investigation of the way that energy is used in New Zealand homes since the 1970s.

The envisaged model of residential energy use used physical building and appliance characteristics as well as socio-demographic factors to describe the energy consumption patterns and some of the energy services, in particular, the achieved indoor temperatures. The model was used to understand current and future national household energy requirements and as a tool to evaluate the implications of building and appliance performance changes.

The project commenced in 1995 with a pilot study and progressed to detailed data collection in 400 houses from throughout New Zealand. The sample included households from large and small cities, urban and rural areas and both the North and South Islands from Kaikohe to Invercargill. Each house were monitored for about 11 months.

HEEP monitoring activities included a detailed occupant survey as well as a detailed house energy examination. The monitoring covered all fuel types (electricity, natural gas, LPG, solid fuel, solar water heaters) as well as temperatures in at least three locations.

Data collection was completed in 2005, and from Year 9, the reports provided regional and national statistics.