The Methodology of Thermal Energy Management for Nearly Zero Energy Buildings

Distributed generation causes an unbalanced power grid, which leads to a problem with unpredicted energy surplus balancing. In this vast problem, active cooperation with individual consumers on the energy market is crucial to ensure stability of the power system. Therefore, basing on analysis of power demand for the power system, the control algorithm of Thermal Energy Management System for the net Zero Energy Buildings was developed. One of the possibility of shifting peak power demand is using a building structure as a thermal energy storage. The potential of energy management was confirmed by numerical analysis of two nearly zero energy building models (a heavy and a light construction). A heavy construction building consumes less energy than a light construction but possibilities of obtaining measurable cost savings for user are higher in a case of light construction building. The objective of this study is to show that it is possible to save about 17–28% of the yearly cost of electricity by using the proposed control algorithm. On the contrary, lack of active and conscious usage will result in yearly increase of energy costs at the level of 5–8%. At the same time functioning of the HVAC system according to the proposed algorithm does not significantly effects on thermal comfort.