Prospect of Solar-assisted Heat Pump Water Heating Systems for Student Residences

Abstract

Water heating is the major energy user in the residential sector. The hot water contribution in the residential sector of South Africa is up to 60% on an average monthly basis and accounts for more than 50% of the monthly electricity cost. Electric storage tank water waters are the main contributors to the high energy consumption in the residences and most of the heating process takes place during the peak times, when electricity is more expensive than off-peak and normal time. This and the growing population and living standards of the economy has led to the high demand of electricity and energy shortage in the country. Reducing the desired end users’ water temperature has been proposed as a solution to reduce the energy consumption this practice increases chances of diseases like legionella pneumophila. The water heating process could be incorporated with the time-of-use (TOU) tariff to reduce the energy consumption by load shifting from peak demand to off-peak or normal time. Renewable energy source technologies can also be used to reduce the energy consumption; however, the renewable energy systems show a common disadvantage in meeting the energy demand during certain climate conditions. And therefore, the hybrid energy systems can be implemented to promote energy conservation and energy efficiency of the renewable energy system. To further reduce the energy consumption, the TOU tariff can be used for optimal control and energy management of the hybrid system.