Analysis of the energy index as a benchmarking indicator of potential energy savings in the San Antonio, Texas single-family residential sector

Energy consumption baselines are essential in promoting energy efficiency programs in an effort to mitigate the environmental impacts of increasing consumption and increasing home sizes. This study calculates baselines, using site and source energy index (EI), of approximately 348,000 detached single-family homes in San Antonio, Texas to facilitate energy efficiency programs. The data analysis pairs building characteristics of individual houses with their energy consumption, allowing researchers to categorically study houses based on EI, vintage (year built), conditioned space (size), and type of fuel and energy utilized. This study found that the size of single-family detached houses has increased over time, while average site and source energy index values have decreased. The majority of single-family detached houses (45.8 % of total or 159,147 houses) have an energy index of 25–50 kBtu/sf/year (78.8–157.7 kWh/m²/year). The majority of all-electric single-family detached houses have been built since 1980, resulting in better performance than anticipated when compared with houses having access to natural gas. Most homes built after 1990 are distributed in the lower (more efficient) energy index categories, indicating that energy efficiency programs for newer, larger houses should be behavioral or educational in nature while programs for older houses should improve the infrastructure.