In this paper, an interdisciplinary team of economists and anthropologists study the perplexing case of Norwegian households’ heat pump ownership. The heat pump is a technology that has the potential to reduce electricity consumption by up to 25% compared to conventional electric heating, but, as we demonstrate in this study, when taken into use it results in little or no change in electricity consumption. To explain this large rebound effect, we use a quantitative economic analysis combined with qualitative interviews attuned towards examining the effect of heat pumps on people’s everyday practices. We find that, on average, households with and without a heat pump use approximately the same amount of electricity. The main sources of rebound identified was higher indoor temperature and heated living space, less firewood and fuel oil use and less use of night-set-backs or reduced temperature while away from the home.