A scheduling optimization model of electric water heaters for electricity cost minimization with limited information

Abstract

The present paper defines the equations that govern the optimization model of an electric water heater in order to manage automatically its available flexibility for the user's own benefit. A case study that focuses on the electric water heater flexibility potential is carried out: it is aimed to minimize the total expected electricity cost of a single household that only has an electric water heater as a flexibility source. The temperature inside the hot water tank is an unknown value since the temperature sensor is not sending any information outside. Moreover, real hot water consumption is uncertain and the model takes decisions based on forecasting models. Given the limited information available, the model is developed in a conservative way with the objective of maintaining both, the hot water temperature and the user's comfort. The results show that it is possible to reduce the electricity bill by managing optimally the available flexibility from the electric water heater.