The impact of housing energy efficiency improvements on reduced exposure to cold — the ‘temperature take back factor’

Energy used in dwellings is an important target for actions aimed at averting climate change. It is increasingly recognised that these actions may also have near-term effects on health arising from changes to the indoor environment. As part of a major study of such health effects, we modelled hypothetical household energy interventions for the UK of the type and scale needed to meet near-term (nominally 2030) abatement targets. Here, we provide details of the elements of our model that address the relationships between the fabric and ventilation improvements and changes in indoor temperature during the heating season — the ‘temperature take back factor’. We demonstrate that the scale of these interventions is consistent with the emission reductions proposed by the UK Climate Change Committee, and estimate that, in the UK, the consequent reduction in exposure to indoor cold may result in around 4400 fewer disability-adjusted life-years each year. The inclusion of the temperature take back factor for the fabric and ventilation interventions reduces the relevant expected CO2 reductions by ~6%. Practical application: Improvements to the UK housing stock aimed at reducing greenhouse gas emissions will result in changes in internal temperatures. Such changes in temperature have implications for both public health and the prediction of emissions reductions. We present here an approach for quantifying the ‘temperature take back factor’, which is of relevance to environmental and energy modelling.