Warmer Kiwis Study: Interim Report an Impact Evaluation of the Warmer Kiwi Homes Programme

Abstract

Over a fifth of New Zealanders find their homes to be too cold and damp. EECA’s Warmer Kiwi Homes (WKH) programme aims to make New Zealand homes warmer, drier, and healthier, while improving their energy efficiency. The programme includes provision of clean heating devices (primarily heat pumps) to household living areas that do not have such heating. We examine impacts that WKH heat pump provision has on household outcomes including comfort and wellbeing, indoor environmental outcomes and electricity use. The evaluation covers 127 households in Auckland/Waikato, Wellington and Christchurch who applied for a heat pump through WKH in 2021. Evaluation methods include two qualitative household surveys, a house survey, indoor environmental quality readings from a monitor in the living area, and electricity use measured using smart meter data. Timing of heat pump installation was effectively randomised by the onset of COVID-19, so enhancing the study’s statistical precision. The qualitative and quantitative data show that houses became more comfortable, warmer and less damp following heat pump installation relative to a house without a heat pump yet installed; CO2 levels also fell. These gains were achieved despite a likely fall in energy use.

Keywords: Heat pumps; indoor temperature; electricity use; wellbeing; Warmer Kiwi Homes

JEL Classification: I18, I31, I38, Q48