Viability assessment of a combined hybrid electricity and heat system for remote household applications

The purpose of this paper is to address the problem of satisfying the energy needs in electricity and heat of a typical remote household in an integrated autonomous manner, employing environmental friendly and sustainable power systems. A hybrid PV/diesel/battery power system is designed to satisfy reliably the electric needs, using the HOMER simulation software. The present work showed that a PV/diesel/battery power system with 1 kW of PV arrays, 1.8 kW sized diesel generator, 2 battery units each of 1 kW h and 1 kW sized power converter is the optimal system for a representative off-grid remote house located in Metsovo, Greece, with the cost of energy rising to 0.553 €/kW h. The optimal hybrid power system presents a cost-effective alternative to conventional electricity grid-extension. The paper also investigates the installation of a 14.8 kW wood biomass burning thermodynamic fireplace alongside a diesel oil burner to cover space heating and hot water requirements, employing the renewables assessment software tool 'RETScreen'. The proposed heating system is viable with Internal Rate of Return of 24.8%. The initial investment of the combined hybrid electricity and heat autonomous system is about 13,600 €. The mitigation of GHG emissions to be achieved is estimated to 13.5 tons CO2-eq/yr, presenting a major improvement of the environmental footprint of the town.