Over 80% of the energy used to heat the water in our homes & businesses goes down the drain! Starting this month, Drexel University will begin researching how we can recover some of that heat from our wastewater. Funded by the Water Environment Research Foundation (WERF) and the New York State Energy Research and Development Authority (NYSERDA), the research will be led by principal investigator, Dr. Charles Haas of Drexel University and Paul Kohl, Energy Program Manager at PWD and a Drexel PhD candidate. Underground, the temperature of our wastewater remains stable year round as it is insulated from the air temperature above it. This means we can use energy from our sewage to warm buildings in the winter and cool them in the summer. Drexel’s “Sewage Geothermal” research will build on existing work at the Water Department to recover energy from our waste water. In fact, PWD installed sewage geothermal technology at our Southeast Water Pollution Control Plant in February 2012. The installation uses thermal energy to heat the plant’s compressor building and pipe gallery space, saving PWD $18,000 annually.