Investigating the hybridisation of micro-scale concentrated solar trigeneration systems and wind turbines for residential applications using a dynamic model

Solar and wind energy sources are envisioned to play a key role in the transition towards fully renewable energy systems but both suffer from their intermittent nature, which can be relieved by hybridisation. Hence, the benefits of the complementarity of these sources are investigated hereunder by considering a small-scale hybrid trigenerative system consisting of a Linear Fresnel Reflector solar field with a 440 m2 collector area, a 20 kWe/100 kWt organic Rankine cycle unit combined with a latent heat thermal energy storage system, an absorption chiller, and a 20 kWe wind turbine for the provision of electricity, heating and cooling to 10 residential apartments. To this end, a dynamic model and suitable control logic are developed to assess and compare the performances of the proposed hybrid system concerning the solar plant and wind turbine separately. The results show that hybridisation can extend the annual thermal coverage by renewables by 3.7–6.1% for the investigated locations by increasing the operation of the organic Rankine cycle unit, especially in winter. In particular, the surplus electrical energy from the wind turbine is used to satisfy 6% and 4% more than the separate configuration of the annual thermal and electrical demands for Ancona. As a result of hybridisation, the annual thermal energy consumption of the boiler reduces by 8.3%, 9.9%, and 37.6% for Perugia, Ancona, and Messina respectively, which shows the impact of the profile of the energy sources. At the same time, hybridisation improves grid stability by reducing the excess electricity production 18.2%, 19.2%, and 26.3% for Perugia, Ancona, and Messina respectively. A sensitivity analysis for Ancona has revealed that the size of the water thermal energy storage tank does not have a significant impact on the electrical and thermal coverage of the hybrid system, while electrical and thermal coverages improve 11.1% and 6.7% respectively by doubling the wind turbine capacity along with a 14.8% drop in the thermal energy consumption by the boiler. In brief, the analysis has shown the complementarity of these energy sources and the benefits of hybridisation for trigenerative systems for residential buildings.