Profitability Analysis and Capital Cost Estimation of a Thermochemical Energy Storage System Utilizing Fluidized Bed Reactors and the Reaction System MgO/Mg(OH)2

Abstract

The storage of industrial waste heat through thermochemical energy storage (TCES) shows high potential to reduce the dependency on fossil fuels. In this paper the capital cost investment of a TCES system utilizing fluidized bed reactors and the reaction system MgO/Mg(OH)2 is estimated and a profitability analysis is performed. The study estimate is based on a simulation study that considers the mass and energy balance of the proposed preliminary heat storage and release processes utilizing fluidized bed reactors. Furthermore, transport, operation and maintenance as well as utility costs were estimated in order to evaluate the profitability of the system. It is concluded that for the selected boundary conditions, the specific investment costs per kW stored heat are approximately 900 e/kW and that the systems should not be installed at sites where less than around 5 MW of waste heat are available. Finally, a sensitivity analysis was conducted, to identify the key process and economic parameters critical for a positive net present value.