Energy and Economic Investigation of a Biodiesel-Fired Engine for Micro-Scale Cogeneration

The work aims at investigating the techno-economic performance of a biodiesel micro combined heat and power (CHP) system for residential applications. CHP unit is based on direct-injection compression ignition engine providing 6.7 kWel 11.3 kWth. A 0D model developed validated to characterise behaviour biodiesel-fired full partial load in terms efficiency, fuel consumption, emissions. Furthermore, non-dimensional polynomial correlations are proposed foresee biodiesel-fuelled engines micro-CHP applications loads. Afterwards, adopted satisfy electric thermal demand domestic users Southern Italy. To this purpose, parametric analysis performed considering different number apartments operating strategies (electric-driven thermal-driven). bi-variable optimisation primary energy saving (PES) index payback period (PBT) permits selecting thermal-driven strategy five as most suitable solution. optimal PBT PES equal 5.3 years 22.4%, respectively. corresponding annual self-consumption reaches 81.3% request, surplus lower than 8%. Finally, sensitivity define influence costs vectors cogeneration economic feasibility system. highlights that investigated apparatus represents an attractive option requests micro-scale applications, valuable advantages compared traditional production.