A Heuristic Approach to Control the Ecovat System

The Ecovat system is a seasonal thermal storage technology developed to supply the heat demand of a neighbourhood of houses throughout the entire year. It consists of a large subterranean water tank which is divided into a number of virtual segments which can be charged or discharged independently from each other. In this work, we present a fast heuristic approach to model and control the charging (store heat) and discharging (withdraw heat) of the Ecovat system. We compare the results obtained with this approach to results obtained with a previously developed integer linear programming model (ILP) of the Ecovat system, which is too slow to be used in practice. The heuristic is found to reduce the computational time from 12+ hours for the ILP model to one second and is thereby suitable to be used in practice. The price for this reduction is an average decrease in performance of 5.2% and a maximum observed decrease of 12.5%.