A load shedding controller for management of residential loads during peak demand periods

South Africa is experiencing an unprecedented increase in electricity consumption. A direct consequence of this increased demand is the enormous load burden that has been imposed on the nation's national electricity grid, especially during peak demand periods. One solution to this problem would be the construction of additional power generating facilities, at a great cost to the economy and more importantly the environment. A more viable solution would be to shift loads off the electricity grid's peak consumption demand periods. To this end we will propose a controller that will reduce the residential load demand burden on the electricity supply grid, plus improve the load factor. The proposed controller allows the user to adjust the threshold setpoint at which the controller must operate. The controller performs the necessary load shedding operations when the setpoint is exceeded. The efficacy of the proposed controller was assessed by managing the load demands of residential consumers. A comparison was made between residential peak period consumption, under controlled and uncontrolled conditions. These comparisons were based on the following aspects: total consumption, maximum demand and load factor. The cost of consumption for each customer was calculated by using a flat rate tariff. The tests demonstrated the following: increases in consumer savings, a significant reduction in maximum demand on the electricity grid during peak consumption periods and improvements in load factor.