The Structure and Intensity of Energy Use: Trends in Five OECD Nations*

This paper examines trends in the structure and intensity of final energy demand in five OECD nations between 1973 and 1988. Our focus is on primary energy use, which weights fuels by their thermal content and multiplies district heat and electricity by factors of 1.15 and 3.24 to approximate the losses that occur in the conversion and distribution of these energy carriers. Growth in the level of energy-using activities, given 1973 energy intensities (energy use per unit of activity), would have raised primary energy use by 46% in the U.S., 42% in Norway, 33% in Denmark, 37% in West Germany, and 53% in Japan. Reductions in end-use energy intensities, given 1973 activity levels, would have reduced primary energy use by 19% in the U.S., 3% in Norway, 20% in Denmark, 15% in West Germany, and 14% in Japan. Growth in national income parallelled increases in a weighted index of energy-using activities in the U. S., West Germany, and Denmark but substantially outstripped activity growth in Norway and Japan. We conclude that changes in the structure of a nation’s economy may lead to substantial changes in its energy/GDP ratio that are unrelated to changes in the technical efficiency of energy utilization. Similarly, changes in energy intensities may be greater or less than the aggregate change in the energy/GDP ratio of a given country, a further warning that this ratio may be an unreliable indicator of technical efficiency.