An efficient design of a data acquisition system to monitor the operating performance of a hybrid solar assisted air source heat pump water heater

Sanitary hot water heating in the residential sector, especially in South Africa is achieved primarily by the conventional electric geyser. This hot water device is inefficient and operates with an energy factor less than 1. The inefficiency of the electric geyser is not only responsible for huge energy consumption, but also associated with significant environmental impact. The implementation of energy efficiency on an existing geyser by retrofitting with a hybrid solar assisted air source heat pump system can go a long way to enhance the operating efficiency well above that which would have been achieved by simple retrofitting with either a standalone air source heat pump unit or a solar water collector. The study focuses on the design of a data acquisition system to monitor the operating performance of an installed hybrid solar assisted air source heat pump water heater. The data acquisition system comprised of ambient weather parameters, thermal and electrical parameters in a bid to ascertain the operating performance of the hybrid solar assisted air source heat pump water heater. The results depicted that the average energy factor of the hybrid system was 3.45 and was higher than the average solar fraction of the standalone solar water heater (0.72) or the average COP of the air source heat pump water heater (2.72). The data acquisition system will assist homeowners, policymakers and energy service company to justify the energy efficiency improvement and the techno-economic viability of retrofitting existing geyser with a hybrid solar assisted air source heat pump system.