Effects of tariffs and energy saving schemes on domestic households energy consumption

Domestic households´ energy consumption makes up a large portion of the total energy usage in South Africa. The use of many inefficient appliances such as incandescent lighting and element-geysers in households is one of the reasons for the large consumption of electricity. The current tariff structures and a lack of knowledge in energy saving schemes by the users could account for inefficient use of energy. To reduce the high energy consumption in commercial and residential buildings, heating appliances based on renewable energy such as solar water geysers can be used. In this paper, energy consumption data from households using electric water heaters were collected and analysed. Simulations were performed to see how much energy could be saved should the households switch to solar geysers, taking into account the present and future tariff structures. It is demonstrated that element-geysers can consume up to 40% of the total energy consumption in a household. It is further shown that the use of heat pumps, solar geysers or other energy efficient appliances to reduce energy consumption by 30% during peak times can lead to an average saving of about 35% of the total electricity bill; whereas a two-hour load shift outside peak times will lead to an average saving of up to about 26% of the total electricity bill.