The role of highly energy-efficient dwellings in enabling 100% renewable electricity

One of the key challenges to achieving high-percentages of renewable electricity supply is the temporal mismatch between non-dispatchable renewable supply and peaks in electricity demand. These challenges become more pronounced as the timescale of this mismatch extends to seasons. Standard policies emphasise supply-side solutions that will result in underutilized supply, storage and transmission infrastructure, and significantly increased decarbonisation costs. Less attention has been placed on demand-side solutions and, in particular, the potential role of high-performance buildings in reducing the demand for electrical heating in winter, addressing the seasonal supply-demand mismatch. This paper quantifies the potential future reduction in winter electrical heating that could be achieved through widespread uptake of energy efficient dwellings in New Zealand a country with a high percentage of renewable electricity. The results show that rapid uptake of currently achievable best-practice standards could reduce the winter-summer demand variation by 3/4 from business as usual by 2050. Therefore, New Zealand, and other countries with seasonal peaks in space heating/cooling demand, should urgently adjust policy settings to mandate highly energy-efficient housing for new-builds and retrofits in order to deliver a least cost low-carbon energy transition, which also captures the well-known social and health co-benefits of improved dwelling performance.

Automated summary

This paper discusses the potential future reduction in winter electrical heating that could be achieved through widespread uptake of energy efficient dwellings, using New Zealand as a case study. The results show that rapid adoption of best-practice standards could reduce the winter-summer demand variation by three-quarters by 2025.