How Much Energy Does CCS Equipment Use?

Written By Teacher: Elizabeth Ward

My name is Elizabeth Ward. I am a former Early Childhood, Elementary, and English as a Foreign Language educator. I have taught third grade Science and Social Studies as well as Kindergarten in both urban and rural Oklahoma public schools. I taught online EFL to students of all ages in China for four years. I also have experience in curriculum development and content design for teachers in the physical and digital classroom. As a former teacher I have a passion for supporting teachers and making their jobs easier. I currently live in the greater Houston area with my husband and four dogs. 

Carbon capture and storage (CCS) can help reduce emissions from fossil fuel power plants, but it also consumes energy, reducing the plant’s overall efficiency. Understanding how much energy is lost in the process allows students to critically evaluate the benefits and limitations of CCS as a climate solution. This topic encourages discussions on energy trade-offs, technological advancements, and the role of CCS in decarbonization efforts. Invite your students to explore energy efficiency with this video for older students or this lesson plan for younger students. 

Written By: MIT Environmental Solutions Initiative

The MIT Climate Change Engagement Program, a part of MIT Climate HQ, provides the public with nonpartisan, easy-to-understand, and scientifically-grounded information on climate change and its solutions.

Fossil fuels are warming the planet because when they’re burned, they release heat-trapping gases like carbon dioxide (CO2). Carbon dioxide is found in the “flue gas” that billows out of power plants’ smokestacks, as part of a mix with nitrogen, water, and small amounts of soot and other chemicals.

But it’s possible to remove the climate-warming CO2 from flue gas before it’s vented, using a technology called carbon capture and storage (CCS).

Most capture systems use chemicals called “amines" to separate CO2 from the gas. The captured CO2 is then compressed, so it can be shipped off for use or to be stored underground. This process is quite energy-intensive. The flue gas must be pumped to different parts of the plant; the CO2 must be separated, cooled down, and pumped to its destination; and the amines need to be “recharged” at the end of the process so the whole operation can begin again. About five percent of the equipment’s total energy use goes to pumping various liquids and gases around the plant, while roughly one-third is used to compress the CO2, according to Howard Herzog, a Senior Research Engineer at the MIT Energy Initiative. The most energy-intensive part of the process is recharging the amines, he says.