Representative hot water draw profiles at high temporal resolution for simulating the performance of solar thermal systems

The heating of domestic hot water (DHW) to supply bathing, cleaning, and appliance needs contributes significantly to energy demands in housing. Despite the demonstrated significance of DHW draw profiles on performance, it is common practice when analyzing solar DHW and solar combisystems to conduct long-term simulations (e.g. annual) using repeating daily profiles. New DHW profiles that can be used for such analyses have been developed based upon measurements that were taken in 73 houses in Québec (Canada). Annual DHW draw profiles at a time-resolution of 5 min have been created for 4 consumption levels and 3 temporal consumption patterns (sparing consumers who tend to use DHW in the mornings, average consumers who tend to use DHW in the evenings, etc.). Simulations of a solar DHW system conducted with these new profiles revealed that both temporal and annually integrated predictions can be significantly affected by timing of DHW draws.