Life cycle assessment (LCA) - from analysing methodology development to introducing an LCA framework for marine photovoltaic (PV) systems

Previously, life cycle assessment (LCA) focussing on principles or applications has been considerably reviewed. Still, an up-to-date review on LCA methodology development (rather than application) in a chronological order which embraces all life-cycle phases is lacking. The objectives of this article include scrutinising methodology development of conventional LCA phase by phase, providing clarification on goal and scope definition and life cycle inventory (LCI) analysis, discussing recent substantial development on life cycle impact assessment (LCIA) methodology and interpretation, and introducing an LCA framework for marine photovoltaic (PV) systems. For the study presented here, literature on LCA methodology development was categorised into Sample Groups A, B and C, comprising 15 review articles published in the last decade, 95 pieces of other literature types (with 83% journal articles), and 38 additional materials necessary for complementing an in-depth discussion respectively. A threefold analysis was performed to scrutinise and compare the literature in these sample groups. The analysis shows that for Sample Group A, the focus has steered from overarching LCA of all-embracing life cycle phases to single phase and then sole engagement with a specific topic; and for Sample Group B, 44% has reported the scientific endeavour on LCIA compared to other life cycle phases. Following clarification on system boundary, cut-off and existing LCI approaches including attributional, consequential, process based, input-output (IO) based etc., the methodology development of impact categories (covering impacts of water use, noise and working environment), uncertainty and sensitivity analyses are discussed. In addition, classification involving series and parallel mechanisms, LCIA development for space use, odour, non-ionising radiation and thermal pollution, rebound effects, renewability of resources, dynamic of environment and future scenario modelling in LCA context are identified as research needs and areas for future development. In compliance with ISO Standards and based on the findings, an LCA framework for marine PV systems (which exemplify the state-of-the-art development of renewable and sustainable energy in marine industry) is introduced to enhance the practical applicability and usefulness of the findings to LCA researchers.