Life Cycle Assessment of Greenhouse Gas Emissions, Water and Land Use for Concentrated Solar Power Plants with Different Energy Backup Systems; by Sharon J.W. Klein and Edward S. Rubin
Concentrated solar power (CSP) is unique among intermittent renewable energy options because for the past four years, utility-scale plants have been using an energy storage technology that could allow CSP plants to operate as a base-load energy generator . No study has directly compared the environmental implications of this technology with more conventional CSP backup energy options. We compare the life cycle greenhouse gas (GHG) emissions, water consumption, and direct, onsite land use associated with electricity production from CSP plants with wet and dry cooling and with three energy backup systems: 1) minimal backup (MB), 2) molten salt thermal energy storage (TES), and 3) a natural gas-fired heat transfer fluid heater (NG). Plants with NG had 4-9 times more GHG emissions than TES plants, and TES plants had twice as many GHG emissions as MB plants. Dry cooling reduced water consumption by 71-78% compared to wet cooling. Larger backup capacities had greater water consumption while NG plants had lower land use impacts.