Warmer Kiwi Homes Research and Evaluation

Publication date: January 2022


EECA has delivered over 365,000 insulation retrofits and 60,000 heating retrofits through its retrofit programmes since 2009.

Warmer Kiwi Homes is EECA’s current programme aimed at making homes warmer, drier and healthier through improved energy efficiency.

EECA is committed to ongoing research and evaluation to support programme design and delivery improvements. This page provides an overview of research into current and previous retrofit programmes.

Warmer Kiwi Homes Impact Evaluation

Phase 2: Warmer Kiwis Study (2021 - ongoing)

The Warmer Kiwis Study is being led by Motu Economic & Public Policy Research. This study specifically focuses on the heat pump component of the Warmer Kiwi Homes programme, and works directly with a group of about 160 homeowners, who have received, or will receive a grant for an efficient heater. Motu is collecting new data on health and wellbeing, the indoor environment in homes (including temperature and humidity), and electricity consumption to investigate the actual improvements achieved through EECA’s programme.

The study began in 2021, with results to be published in December 2022.

Interim results from the first winter of the study were published in January 2022.

View the webinar: The Warmer Kiwis Study - An impact evaluation of the Warmer Kiwi Homes programme(external link)

To find out more visit Motu's website(external link)

Read the media release announcing Phase 2 Media release May 2021

Phase 1: Review and scoping (2020)

In 2020, EECA commissioned Motu Economic & Public Policy Research and Allen & Clarke to review current evidence supporting the Warmer Kiwi Homes programme and estimate its current impact. This work also suggested areas for further study, which informed the scope of the subsequent Phase 2 Warmer Kiwis Study (described above).

Smart meter data analysis by Vector (2022)

Vector has modelled the impact of EECA’s retrofit programmes on household electricity consumption by combining smart meter data with data supplied by EECA on insulation and clean heater retrofits. The analysis draws on data from the Warmer Kiwi Homes and predecessor Warm Up New Zealand programmes and covers owner-occupied and rental properties. It is complimentary to the Warmer Kiwi Homes impact evaluation in that it spans a number of EECA programmes and hence target groups, but explicitly excludes any demographic information on households.

These results inform future demand projections, which Vector uses for network planning and management, and may be used to further analysis of emission reduction opportunities. For EECA, this analysis helps us to design high-impact retrofit programmes in the future.

To find out more visit the Vector website(external link)

Warm Up New Zealand cost benefit analysis (2012)

A comprehensive cost benefit analysis of the Warm Up New Zealand: Heat Smart programme was completed by Motu Economic & Public Policy Research, Covec, The University of Otago and Victoria University of Wellington in 2012. This report was the first of its kind worldwide to prove the significant health benefits of a large-scale insulation programme, and the favourable benefit-cost ratio resulting from this.

To find out more visit the Motu website(external link)