- A new economic analysis of carbon capture and sequestration (CCS) concludes it is more expensive and less efficient than estimated in a landmark 1991 Electric Power Research Institute (EPRI) study.
- University of Michigan researchers say the 1991 EPRI pilot study put the increased annual cost of a CCS-equipped plant over a conventional plant at $29 million but, because capturing the emissions would require increased burning of coal, the actual additional cost is closer to $126 million annually.
- At this cost — more than four times the original estimate — a solar power plant with comparable generation capacity would be cost-competitive with CCS, according to analysis co-author Sarang Supekar. Wind, he added, is already less expensive than a new coal plant.
CCS infrastructure added to plants that burn coal to generate electricity enable them to capture and bury their tons of climate change-inducing greenhouse gas emissions (GHGs).
“Depending on the source of heat used to meet the steam requirements in the capture unit, retrofitting a PC power plant that maintains its gross power output (compared to a PC power plant without a capture unit) can cause a drop in plant thermal efficiency of 11.3–22.9%-points," according to the report abstract. "This estimate for efficiency penalty is significantly higher than literature values and corresponds to an increase of about 5.3–7.7 US¢/kWh in the levelized cost of electricity (COE) over the 8.4 US¢/kWh COE value for PC plants without CO2 capture."
“PC power plants with CO2 capture are likely to remain less competitive than natural gas combined cycle (without CO2 capture) and on-shore wind power plants, both from a levelized and marginal COE point of view,” it adds.
“The one-line conclusion is that coal should stay in the ground,” Supekar said, though CCS-enabled natural gas plants might mitigate the variability of solar and wind.