A review on life cycle assessment of concentrating solar energy technologies

Solar energy technology is identified as one of the most important contributors to the decarbonization of the energy system and the economy, which requires the further development of these technologies with higher efficiency, and lower environmental impacts. The paper systematically reviews the energy and environmental impacts and costs of concentrating solar technologies, applying the life cycle approach. The concentrating solar technologies are described technically, which is followed by an analysis of life cycle assessment methods being currently applied in this context. The life cycle energy requirement, greenhouse gas emissions, resource consumption, other environmental impacts and costs of the technologies are reviewed by the types of technologies and the choice of assessment methods. The obtained findings show that the lower cumulative energy demand (CED) and global warming potential (GWP) of concentrating solar power (CSP) and high concentrating solar photovoltaics in high solar radiation areas, while higher CED and GWP of CSP and concentrating solar thermal hybridized with fossil fuels. Furthermore, it is indicated through the dominance analysis that construction, material extraction and manufacturing are the largest contributors to the single endpoint impact. For specific midpoint impacts, the hotspot lies in manufacturing (for energy demand, material depletion and ecotoxicity), operation (for GWP) or both of these stages (for water consumption). Disregards of stages, the solar concentrator is the component causing the largest share of several midpoint impacts such as energy demand, GWP, material depletion and ecotoxicity. In term of costs, the levelized cost of energy from CSP system tends to decrease thanks to the reduction in solar concentrator cost, and the combination of CSP and PV brings the lowest cost with reduced GWP.