Implications of integrating electricity supply dynamics into life cycle assessment: A case study of renewable distributed generation

Electricity supply is frequently cited as a significant hot spot in life cycle assessment (LCA) results. Despite its importance, however, LCA research continues to overuse simplified methodologies regarding electricity supply modeling. This work aims to demonstrate the usefulness of electricity trade analysis (proposed model) for integrating the short-term dynamics of electricity supply and refining LCA results. Distributed generation using renewable energy is applied as a case study to demonstrate how electricity trade analysis provides more refined estimates when environmental impact abatements are assessed compared with the conventional (simplified) approaches in LCA. Grid-connected photovoltaic panel (3 kWp mono- and poly-crystalline) and micro-wind turbine (1, 10 and 30 kW) environmental impact abatements are investigated by determining the displaced marginal electricity production on an hourly basis. The results indicate that environmental impact abatements calculated using the developed short-term time horizon approach can be significantly different (up to 200% difference) from those obtained using a simplified approach. Recommendations are provided to LCA practitioners to address this issue of differing results.