| The present research focuses on the study and optimization of a thermal storage system by mass of water in a tank buried in the ground. Connected to solar collectors and coupled to a water / water heat pump, the water tank stores the heat collected in summer and releases it in winter for space heating and domestic hot water. Thermal storage is also carried out at the request of air conditioning. The building under consideration is a single family house located in Granby near Montreal with a heated area of 584 m2. In the basic system, the water tank has a storage volume of 30 m3, the solar collectors have an area of 6m2 and the heat pump has a capacity of 1.5 tons of refrigeration. Heating is provided by underfloor heating and an air handling unit. The heating coil is connected to a hot water tank and the cooling coil is connected to a cold water reservoir connected to the heat pump. The building load profile was achieved with a TRNBUILD modeling. The heating and cooling system has been modeled and simulated on the TRNSYS software. The results show a total load of 36344 kWh for space heating, domestic water and air conditioning.;The basic system allows a total annual saving of 3679 kWh. With a sensitivity study, we have selected two optimized systems. The results demonstrate the importance of the storage volume and tank insulation parameters of the buried tank in the ground. The more storage volume, the greater the annual energy saving is going from 3679 kWh with a storage tank 30 m3 to 11344 kWh for a 100m3 reservoir coupled to 3 instead of 2 collectors in the initial case.;The insulation of the storage tank also plays an important role in the energy balance since changes from 13509 kWh of energy savings for a single system 21973 kWh, for non-isolated system. The results show the technical feasibility of heating and cooling system thermal storage, even in a northern climate like Quebec.;To conclude this brief, a small economic study was carried out. Despite the great amount of energy savings conducted annually, such a project is not profitable from an economic point of view due to the low cost of electricity in Quebec since the period of return on investment of the most economical system 38.6 years. |
