The Influence of a Rooftop Photovoltaic System on the Electricity Consumption of a Plastic Moulding Plant: A Carbon Footprint Assessment

Industries are adopting measures to mitigate their carbon footprint, including generating renewable energy for internal use. This study evaluates the carbon footprint of electricity consumption in a plastic moulding plant, focusing on the influence of a rooftop photovoltaic (PV) system installed for self-consumption. Employing a life cycle "cradle-to-grave" model, we assess the PV system's impact on the energy consumption of the plant, considering varying electricity demands over different years, aiming to quantify the avoided Greenhouse Gas (GHG) emissions and GHG payback period. Two electricity consumption profiles are devised to measure emissions: (a) Combined (PV + grid) and (b) Grid-only. The findings indicate a substantial influence of the displaced electricity mix on the PV system's emissions payback. For 2020-2022, the carbon footprint payback of the PV system is achieved in under half of the expected panel lifetime, avoiding around 25 tonnes CO
2
eq per year. However, under an electricity mix with 85% renewables, the payback extends to two lifetimes (57 years), avoiding around 5 tonnes CO
2
eq per year. Thus, the study anticipates scenarios where GHG emissions payback could significantly escalate with the increase of renewables in the electricity grid. Consequently, aligning with policies promoting PV panel installation, a comprehensive life cycle analysis of these systems is recommended to avoid contributing to increasing global emissions.