An interdisciplinary approach towards a detailed assessment of energy consumption in urban space-heating and cooling is presented in terms of measurement and modeling results. Modeling efforts concentrated on the city of Minneapolis, MN, using data from the winter seasons 1977/78 and 1978/79. Further developments of a reference model also fall back on data from Cheyenne, WY, and Greeley, CO. Mean absolute daily errors of gas consumption estimated by the physical model applied to Minneapolis are 6.26% when compared to actual energy usage for the period 12/1/77 to 2/28/78. The mean daily absolute errors for the statistical reference model for the same time period were 5.54%. Modeling of the energy consumption required detailed input of meteorological parameters from a special network of stations. As a spin-off an assessment was obtained of the effects of anthropogenic heat on urban heat-island generation under various synoptic conditions. A detailed building census, comprised of 105.722 heated structures, was obtained. A field survey in Greeley indicated that investment returns from insulating houses might not be as high as hoped for; possibly a considerable amount of insulating material is applied wastefully. Misinformation seems to be the primary cause of misguided energy conservation. Progress in conservation could be …