Solar Powered Steam-methane Reformer Economics☆

Abstract With funding from the U.S. Department of Energy (DOE) and SolarThermoChemical LLC, PNNL is developing a solar-powered steam-methane reformer (SMR). The reformer sits at the focal point of a parabolic dish concentrator, with the concentrated solar energy providing the endothermic heat of reaction. The result is a syngas comprising mostly H2 and CO with a heating value approximately 27% higher than the entering natural gas. On-sun testing completed in 2013 achieved a solar-to-chemical energy conversion efficiency as high as 69%, based on the ratio of incremental chemical energy created to direct normal insolation striking the parabolic dish concentrator. Advanced designs are expected to improve upon this performance. Details regarding the design and performance of the solar reformer are presented elsewhere. This paper describes the projected economics of the parabolic dish SMR system. The key metrics are the levelized cost of electricity for a modified, combined-cycle power plant that operates with natural gas or syngas from the dish SMR, and the levelized cost of chemical energy based on the incremental chemical energy produced in the SMR. The latter can be compared to the levelized cost of natural gas over the life of the solar-powered system. Initial capital and annual maintenance cost estimates for each system component are also presented.