Performance and Cost of Energy Transport and Storage Systems for Dish Applications Using Reversible Chemical Reactions.

摘要

The use of reversible chemical reactions for energy transport and storage for parabolic dish networks is considered. Performance and cost characteristics are estimated for systems using three reactions (sulfur-trioxide decomposition, steam reforming of methane, and carbon-dioxide reforming of methane). Systems are considered with and without storage, and in several energy-delivery configurations that give different profiles of energy delivered versus temperature. Cost estimates are derived assuming the use of metal components and of advanced ceramics. (The latter reduces the costs by three- to five-fold.) The process that led to the selection of the three reactions is described, and the effects of varying temperatures, pressures, and heat exchanger sizes are addressed. A state-of-the-art survey was performed as part of this study. As a result of this survey, it appears that formidable technical risks exist for any attempt to implement the systems analyzed in this study, especially in the area of reactor design and performance. The behavior of all components and complete systems under thermal energy transients is very poorly understood. This study indicates that thermochemical storage systems that store reactants as liquids have efficiencies below 60%, which is in agreement with the findings of earlier investigators. The cost estimates for transport systems have been compared with estimates reported elsewhere for steam and molten-salt thermal energy transport. Based on this comparison, it appears unlikely that reversible-reaction transport will have a compelling advantage in the 427 to 510 exp 0 C range. This study includes a reactor/heat-exchanger configuration that may, at increased cost, increase the delivery temperature to 790 exp 0 C or above. In this temperature range, little data exist on thermal (sensible or latent heat) energy transport. (ERA citation 10:018177)