Efficiency retrofits of 236 properties showed a combined water and energy savings of $4.3 million over a one-year period, according to research by Bright Power and the Stewards of Affordable Housing.
The research focused on two programs – HUD’s nationwide Green Retrofit Program and the Energy Savers program offered by Illinois’ Elevate Energy and the Community Investment Corporation. One year of pre- and post-retrofit utility bills were collected for 236 properties and analyzed.
Both programs showed significant water, energy and cost savings.
Properties in the Green Retrofit Program had reduced water consumption of 26 percent or $95 per unit, per year. This equaled an annual savings of approximately $1.2 million.
Energy consumption of properties surveyed in the Green Retrofit Program was reduced by 18 percent, which achieved estimated savings of $213 per unit, per year, or $3.1 million annual savings, including both electricity and gas.
In the Energy Savers program, gas consumption was reduced by 26 percent on average, with an estimated savings of $381,000 for the 57 properties analyzed. In the most energy-intensive properties, Energy Savers reduced excess waste by an average of 47 percent.
The study noted that properties with higher pre-retrofit water use intensity showed a positive correlation with post-retrofit water savings. Similarly, higher pre-retrofit energy use intensity achieved higher post-retrofit savings in both the Green Retrofit Program and Energy Savers data sets.
Additional observations included:
- Water saving measures in the Green Retrofit Program suggest a simple payback period of one year and a savings-to-investment ratio of nine using the marginal cost of measures.
- The energy savings measures in the Green Retrofit Program resulted in an estimated simple payback period of 15 years and a savings-to-investment ratio of 1.2 using the marginal cost of measures.
- The gas saving measures in the Energy Savers group showed a simple payback period of 7.3 years and a savings-to-investment ratio of 2.8 based on the full cost of measures.
For all three sets of measures, the lifecycle cost of saved energy or water was less than the projected cost of buying energy or water.