The photo is sourced from iea.org
The IEA data include only thermal power plants (TPPs) where CCUS systems can cut emissions from coal and gas combustion. The median estimate of the Intergovernmental Panel on Climate Change (IPCC) says that average greenhouse gas emissions total 820 grams of CO2 equivalent per kilowatt-hour (kWh) of electricity for coal-fired power plants, and 490 grams of CO2-equivalent for gas-fired power generation, which is multiple higher than the same indicator for nuclear reactors (12 grams of CO2 equivalent). Emissions can be reduced by using monoethanolamine, colourless liquid with a mild ammonia odour, well absorbing carbon dioxide then extracted from the liquid by drying. An alternative is the use of metal-organic frameworks (MOFs) – crystalline porous materials consisting of metal ions bound together by organic molecules. MOF pores can absorb external substances and release them when the temperature and the pressure change.
CCUS technologies are highly capital intensive. If the average cost of commissioning combined-cycle gas power plants (the most common type of gas-fired TPPs) in the US is not more than $1,330 per kW, then when using CCS systems (without carbon dioxide utilisation) capable of absorbing up to 90% of carbon dioxide emissions, this increases to more than $3,000 per kW. A similar increase in costs is typical for coal-fired generation. The Energy Information Administration (EIA) estimates that the unit capex of ultra-supercritical coal-fired TPPs having the highest coal combustion efficiency is just over $4,500 per kW of capacity, with CCS systems this figure exceeds $7,100 per kW, which is comparable to the average capex of nuclear reactors.
High capex constrains commercialisation of CCUS technologies. According to IEA estimates, carbon capture, utilisation and storage accounted for only 0.02% of global investments in global energy development in 2023. Limited markets also still remain a problem. The most effective method of carbon dioxide utilisation is reinjection into a reservoir, allowing to increase oil recovery. This method is generally used by oil companies that do not purchase for this purpose carbon dioxide from third-party suppliers. Alternatives include production of carbonated beverages and use of CO2 for reactor cooling. However, the market for these technological solutions remains quite narrow.
