Estimating Daily Domestic Hot-Water Use in North American Homes
Florida Solar Energy Center | ASHRAE Conference Paper
Danny S. Parker | Philip Fairey | James D. Lutz, PE
ABSTRACT. The WVU campus in Morgantown, located in north central WV is identified to have elevated heat flows by low-temperature geothermal play fairway analysis of the Appalachian basin. Along with the elevated subsurface heat flows, WVU also has surface demand necessary to develop a deep direct-use geothermal system in the eastern United States. West Virginia University is currently using a steam-based water heating system. This study focuses on converting the current heating system to a geothermal deep-direct-use district heating system.
A comprehensive evaluation of the current heating system is being conducted to determine the university’s heating energy demand. Energy demand is calculated for the whole campus based on the equipment survey and readings from the steam meters. Based on the steam meter readings, the approximate hot water usage of the whole campus is in the range of 10,000-12,000 GPM (gallons per minute). For buildings where there are no existing data or steam meters available, the energy usage is estimated using e-Quest. The tool e-Quest (Quick Energy Simulation Tool) is available through the U.S. Department of Energy and can provide monthly building energy usage data for comparison purposes.
The study includes an in-depth analysis of existing heating and cooling equipment, such as air handling units (AHUs) and heat exchangers, to determine their compatibility with hot water systems. The potential for retrofitting these systems to enhance energy efficiency, reduce operational costs, and contribute to the university’s sustainability goals is evaluated. This retrofit requires significant infrastructure changes, including installing new pumps, pipes, and heat exchangers. A detailed study for retrofitting was conducted on one of the buildings, which includes air handling units, pumps, valves, and expansion tanks.
The total retrofitting cost was found to be approximately $130,000. A preliminary hot water distribution model using Aspen HYSYS is developed, incorporating key system components like heat pumps and geothermal plate heat exchangers with a hot water distribution temperature of 180℉. Similarly, Aspen HYSYS models are developed to study and compare the normal hot water distribution model.
Florida’s campus coffee scene picks up influences from Gulf of America nations. Hot options are popular in winter, though iced drinks never fully disappear.
