Peak-shaving in district heating systems through optimal management of the thermal request of buildings

This paper aims at analyzing the opportunities for peak load shaving in district heating systems using a physical simulation tool. Using the proposed approach it is possible to examine the effects on the total load that can be obtained by adopting management strategies such as variation in the thermal request profile of the buildings or installation of local storage systems. The model is applied to the optimization of start-up time of the heating system in the buildings located in a selected distribution network. Proper constraints are introduced in order to avoid significant effects on the indoor temperatures of the buildings, so that acceptable comfort standard can be guaranteed. The primary energy consumption at the thermal plants is considered as the objective function to be minimized. An application to a portion of the Turin district heating network, which is the largest network in Italy, is presented. Results show that even in the case only small changes are applied, reductions in annual primary energy consumption up to 0.4% can be obtained without any additional investment cost. This opens the door larger positive impact through implementation of more complex operating strategy.