Technical-Economic Feasibility Study of Hybrid CSP Plants With Gas in Chile

Abstract

The Chilean government has presented an accelerated decarbonization plan, proposing the closure of coal-fired power plants by 2025, to combat climate change. Therefore, it is important to migrate to new forms of cleaner generation that are also safe for the electricity system. It is in this context that the motivation arises to study the hybridization of two technologies usually opposed, such as CSP and Gas, to enhance the benefits of each one. The plant to be evaluated has a HYSOL configuration, which consists of a Solar Tower with thermal storage of salt to which is incorporated a gas cycle whose exhaust gases are used to heat the salt when necessary. For this study, SAM was used to model the solar field and EES was used to simulate the thermodynamic components of the Brayton and Rankine cycles. The study is carried out at 3 locations in the Antofagasta Region. Capacity factors close to 90% are obtained, which is higher than most of the Non-Conventional Renewable Energies. Similar CO₂ emission factors are obtained in the 3 locations and around 0,12 Ton CO₂/ MWh, which is substantially lower than other generators based on conventional fuels. The lowest LCOE occurs in L2 and has a value of 82,9 USD/MWh, being more cost effective than Open Cycle Gas and Nuclear technologies and could become competitive in the future with other technologies if the costs associated with the solar field are reduced as expected. It’s concluded that the proposed solution is technically and economically feasible.