Systems analysis of major consumer energy decisions

Abstract

American consumers make a number of decisions that significantly impact their energy use. Some of the most important of these decisions were identified and analyzed for the purpose of including them in a Consumer Energy Decisions Model (CEDM). These decisions included housing choices that affect space heating, water heating, solar photovoltaic and transportation. The CEDM was used to calculate values of recurring and capital cost for all permutations of all the decision components for New York City, Minneapolis and Seattle. These results were analyzed using Pareto plots of recurring versus capital cost. There was a wide range of costs associated with the different solutions, indicating that there is tremendous value in making good energy decisions. The type of vehicle showed the most notable effect on return on investment. Four vehicles were analyzed, a Toyota Camry, Camry Hybrid, Jetta Turbo Diesel (TDI) and an electric Nissan Leaf. The hybrid showed the worst return on investment relative to the Camry with a payback rate of about 9 years, while the TDI and Leaf had payback rates of 1-2 and 6-10 years relative to the Camry, with the added benefits of using less energy and emitting less CO₂. Housing choices were the next most favorable investments, with payback rates around 10 years for the most economical choices. They showed good returns at some points but showed diminishing returns as continued improvements were made. Finally, the solar PV and solar hot water options are bad investments for the sites analyzed, which receive much less sunlight than other parts of the country. The effects of incentives and tax credits were not analyzed in this study.