Techno-Economic Assessment of a Combined Heat and Power Plant Integrated with Carbon Dioxide Removal Technology: A Case Study for Central Poland

• Main Authors: Paweł Gładysz, Anna Sowiżdżał, Maciej Miecznik, Maciej Hacaga, Leszek Pająk
• Format: Article
• Language: English
• Published: MDPI AG 2020-06-01
• Series: Energies
• Subjects: CO2 capture; utilization and storage; combined heat and power; CO2 enhanced geothermal systems; supercritical CO2 power cycles; biomass
• Online Access: https://www.mdpi.com/1996-1073/13/11/2841
• ISSN: 1996-1073

The objective of this study is to assess the techno-economic potential of the proposed novel energy system, which allows for negative emissions of carbon dioxide (CO₂). The analyzed system comprises four main subsystems: a biomass-fired combined heat and power plant integrated with a CO₂ capture and compression unit, a CO₂ transport pipeline, a CO₂-enhanced geothermal system, and a supercritical CO₂ Brayton power cycle. For the purpose of the comprehensive techno-economic assessment, the results for the reference biomass-fired combined heat and power plant without CO₂ capture are also presented. Based on the proposed framework for energy and economic assessment, the energy efficiencies, the specific primary energy consumption of CO₂ avoidance, the cost of CO₂ avoidance, and negative CO₂ emissions are evaluated based on the results of process simulations. In addition, an overview of the relevant elements of the whole system is provided, taking into account technological progress and technology readiness levels. The specific primary energy consumption per unit of CO₂ avoided in the analyzed system is equal to 2.17 MJ_LHV/kg CO₂ for biomass only (and 6.22 MJ_LHV/kg CO₂ when geothermal energy is included) and 3.41 MJ_LHV/kg CO₂ excluding the CO₂ utilization in the enhanced geothermal system. Regarding the economic performance of the analyzed system, the levelized cost of electricity and heat are almost two times higher than those of the reference system (239.0 to 127.5 EUR/MWh and 9.4 to 5.0 EUR/GJ), which leads to negative values of the Net Present Value in all analyzed scenarios. The CO₂ avoided cost and CO₂ negative cost in the business as usual economic scenario are equal to 63.0 and 48.2 EUR/t CO₂, respectively, and drop to 27.3 and 20 EUR/t CO₂ in the technological development scenario. The analysis proves the economic feasibility of the proposed CO₂ utilization and storage option in the enhanced geothermal system integrated with the sCO₂ cycle when the cost of CO₂ transport and storage is above 10 EUR/t CO₂ (at a transport distance of 50 km). The technology readiness level of the proposed technology was assessed as TRL4 (technological development), mainly due to the early stage of the CO₂-enhanced geothermal systems development.