The Electric Power Research Institute, Inc. (EPRI) is an organisation that carries out research and development relating to the generation, delivery and use of electricity for the benefit of the public.
The institute has looked into several technologies available (or are currently being developed) that have the potential to enable coal-fired power plants to significantly reduce CO2 emissions through more efficient combustion and use of heat, compared to the use of carbon capture and storage (CCS).
While CCS is considered be the leading option to reduce carbon dioxide emissions from coal-fired power plants. There are many technological, policy and cost challenges that hinder its deployment.
The EPRI's paper analyses current and anticipated US and global CO2 emission standards for coal-fired power plants, identifies major challenges associated with CCS deployment and provides detailed descriptions of coal-only technologies that are not ready for commercial deployment but that present significant opportunities to reduce CO2 emissions.
The results of the study have been published in a new white paper: Can Future Coal Power Plants Meet CO2 Emission Standards Without Carbon Capture and Storage?
Currently, the most efficient coal-fired power plants are the ultra-supercritical coal plants, which produce steam at high temperature (above 593°C or 1100°F) and emit approximately 800 kg (1760 lb) CO2/MWh. The EPRI focused on several technology options for increasing the thermal efficiency of the processes for generating electricity with coal, including:
- Rankine cycles (used by most of today's coal plants) with higher steam temperatures.
- Combined heat and power applications (also known as cogeneration).
- Coal gasification integrated with one of four systems – combined cycles (gas turbine plants), supercritical CO2 Brayton cycles (which use the CO2 instead of water or steam as the working fluid), solid oxide fuel cells (SOFCs), and "triple cycles" (a combination of combined cycles and SOFCs).
None of the options considered in the EPRI's analysis are currently commercially available, economically viable and suitable for broad deployment. Therefore more development needs to be made to progress these technologies.
National R&D programs in the US and elsewhere are making progress, but additional public-private R&D investment is needed to accelerate the deployment of many of these technologies.
"It's critically important for the electric power industry to have as many generation technology and fuel options as possible," commented EPRI Vice President of Generation, Tom Alley. "Reducing emissions will be one of the key drivers as the industry makes decisions about existing assets and about the designs and fuels used in the next generation of power plants. EPRI research like this can be invaluable in informing those decisions."
Edited from press release by Harleigh Hobbs
Read the article online at: https://www.worldcoal.com/coal/12112015/attaining-co2-emissions-limits-without-carbon-capture-storage-3147/