Energy-efficient technology retrofit investment behaviors of households in lower and higher income regions

Urban regions consume approximately 65% of all energy produced and emit 70% of the CO2 to the environment. Buildings, specifically, consume approximately 40% of energy in developed countries and emit nearly 40% of CO2. Most of this energy is used for heating, cooling, and lighting end uses. Since approximately half of building energy use is attributed to residential buildings in the U.S., improving their energy efficiency will help to reduce energy use substantially, as well as benefit households through reduced energy costs. However, little effort has focused on understanding how energy efficiency investments are made, particularly across different socioeconomic groups. Using data for residential buildings in Cedar Falls, Iowa, including energy efficiency investment data for a utility rebate program, assessors data, and U.S. Census data, residential energy efficiency investments are studied in three stages using different subdivisions of the datasets through multistage sampling analysis. Frequency analysis, correlation analysis, and principal component analysis are used to study household investment behavior in (Stage 1) the overall dataset for the city, (Stage 2) the lowest and highest income census tracts, and (Stage 3) a subset of similar housing units in the lowest and highest income census tracts. Specifically, energy efficiency investments in efficient lighting, air conditioners, furnaces, and insulation are studied. Overall, for residential buildings in this region, efficient lighting was the most invested in technology, followed by air conditioners and furnaces, and finally, insulation. If grouping air conditioners and furnaces together, HVAC systems are the most common investment. Interestingly, air conditioners and furnaces are, by far, the most expensive technology to invest in, compared to most other energy efficient technologies used in homes, yet they are among the most common types of investments. They also appear to be an entry point to investing in energy