TECHNICAL, ECONOMIC AND ENVIRONMENTAL FEASIBILITY OF A REAL HYBRID mCHP SYSTEM BASED ON RESIDUAL BIOMASS GASIFICATION AND SOLAR PV: A TRANSIENT NUMERICAL STUDY

Renewable energy sources exploited for Combined Heat and Power (CHP) generation purposes represent a suitable solution for an efficient energy production in industrial and commercial applications, helping to reduce the consumption of fossil fuels and the related emission of GreenHouse Gases (GHG). The aim of this work is to assess the technical, economic and environmental feasibility of an integrated CHP plant, where an Internal Combustion Engine (ICE) fuelled with syngas deriving from gasification of residual biomass is combined with a PV solar system. The ICE has a rated power of 20 kWel and a thermal capacity of 40 kWth; this last achieved by recovering heat from the cooling circuit and from the exhaust gases; the PV system has a peak power of 20 kWel. A 100-kWh lithium battery is also included in the proposed layout, to manage the electrical energy fluxes to and from the national grid. The overall system is dynamically simulated within the TRNSYS environment, with the scope of assessing the conversion efficiency with respect to an annual dynamic load relevant to the energy consumption of a generical farmhouse where the gasifier feedstock is available. The proposed layout reveals as an efficient solution to totally cover the thermal demand during the whole year, as well as to match the electrical load for most of the period analysed. The implemented solution may lead to a reduction of almost 76 tons of CO2 emitted per year, with a related cost saving of about 393 kEUR in an estimated lifetime of 25 years.