Performance analysis of a near zero CO2 emission solar hybrid power generation system

• A novel solar hybrid power system with near zero CO2 emission has been proposed.
• The system integrates fuel reforming, solar-driven steam generation and CO2 capture.
• Solar heat upgrading and high-efficiency heat-to-power conversion are achieved.
• The system accomplishes near zero CO2 emission with oxy-fuel combustion.
• The system thermodynamic performances have been investigated and compared.

A novel solar hybrid power generation system with near zero CO2 emission (ZE-SOLRGT) has been proposed in the previous work, which is based on a GRAZ-like cycle integrating methane–steam reforming, solar-driven steam generation and CO2 capture. Solar heat assistance increases power output and reduces fossil fuel consumption. Besides near zero CO2 emission with oxy-fuel combustion and cascade recuperation of turbine exhaust heat, the system is featured with indirect upgrading of low-mid temperature solar heat and its high efficiency heat-to-power conversion.A performance analysis of ZE-SOLRGT cycle has been carried out using ASPEN PLUS code to explore the effects of key parameters on system performances. It is concluded that ∼54% exergy efficiency can be attained with ∼100% CO2 capture. The net solar-to-electricity efficiency can reach up to 34.7% in the base case. Steam-to-methane molar ratio of 2–3 is suitable for system performance improvement. High system efficiency can be obtained as the HPT pressure ratio is in the range of 15–18. The system integration achieves the complementary utilization of fossil fuel and solar heat, as well as their high-efficiency conversion into electricity.