Design of small cogeneration system for public buildings in the town of Matera

The present work is focused on a small-cogeneration system design for three school buildings in the town of Matera on which it was conducted an energy audit in dynamic conditions in order to define energy demand necessary for the small-cogeneration system design. Cogeneration, also known as CHP (Combined Heat and Power), through the joint and the simultaneous production of electricity (or mechanical) and useful heat from a single energy source, aims at more efficient use of primary energy, with savings on production processes, where there is a strong coincidence in time between electrical and thermal extraction. Cogeneration system power is calculated as indicated in standard UNI/TS 11300-4:2016. Remarkable it is also the economic advantage through the access to White Certificates, Italian incentive system. The CHP system is designed on electricity request of the case studies analysed and its power is 90 kWel with a pay-back time between three and four years. In order to satisfy the entire heating energy demand for the entire district, the authors hypothesized interventions on envelope and system plant. In this case the pay-back period increased and it is between 6-7 years considering White certificates and Thermal Bill.2.0 incentives.