ECONOMIC AND ENVIRONMENTAL ASSESSMENT OF RENEWABLE ENERGY AND ENERGY STORAGE INTEGRATION IN STANDALONE POLYGENERATION SYSTEMS FOR RESIDENTIAL BUILDINGS

Energy consumption and CO2 emissions in residential sector plays an important role to face the climate change. Technologies and strategies which allow the reduction of fuel consumption and CO2 emissions in energy supply systems for residential buildings are required. This work analyses the integration of different renewable energy and energy storage technologies for a residential building located in Zaragoza, Spain. It is selected a standalone energy system in order to study in a systematic way how different technologies interact and affect the optimal design, from conventional to polygeneration systems. A Mixed Integer Linear Programming (MILP) model was developed to optimize the system from the economic point of view whereas CO2 emissions are calculated simultaneously. Results show that photovoltaic technology provides a remarkable reduction of costs and along with cogeneration allow a significant CO2 emissions reduction as well. In addition, it was determined the synergies of different technologies, e.g. batteries capacity is reduced when cogeneration and thermal energy storage are considered. Furthermore, a sensitivity analysis of the number of cycles of the Ion Lithium batteries was carried out to show its competitiveness with respect to lead acid batteries.