The Environmental Protection Agency is working on a new rule that would set stringent limits on carbon dioxide (CO2) emissions from US power plants. Utilities would be required to retrofit existing plants with carbon capture and storage (CCS) technology or to switch to hydrogen fuel. Others call for the use of CCS to decarbonize heavy industry. But the cost of capture and the amount of CO2 that proponents say needs to be captured crush any ideas about feasibility.
Carbon capture and storage is the process of capturing carbon dioxide from an industrial plant before it enters the atmosphere, transporting it, and storing it for centuries to millennia. Capture may be accomplished by filtering it from combustion exhaust streams. Pipelines are proposed to transport the captured CO2. Underground reservoirs could be used for storage. For the last two decades, advocates have proposed CCS to reduce emissions from coal plants and steel, chemical, and other hard-to-decarbonize industries in order to fight human-caused climate change.
CCS has been slow to take off due to the cost of capture and the limited salability of carbon dioxide as a product. Thirty-nine CCS facilities capture CO2 around the world today, totaling 45 million tons per year, or about 0.1 percent of industrial emissions produced globally. Of these, 20 reside in the US or Canada, six in Europe, and five in China. Twenty-four of these facilities use captured CO2 for enhanced oil recovery. Captured CO2 is injected into oil wells to boost oil output,
The news from these facilities is mixed. Many are not meeting their carbon-capture goals or are incurring costs well over budget. Nevertheless, Australia, Canada, China, Japan, the US, and nations of Europe now offer billions in direct subsidies or tax breaks to firms for capture of CO2 emissions and to build pipelines and storage. Over 300 large and small capture projects are in planning around the world which, after completion, may be able to boost capture to 0.5 percent of man-made emissions.
Illinois, Iowa, and other states are struggling with issues involving plans for CO2 pipelines. Ethanol plants and other facilities propose to capture CO2 and need a new network of pipelines to transport the gas to underground storage sites. These pipelines face strong opposition from local communities over farmland use and safety concerns in the case of a pipeline rupture.
Carbon capture and storage is very expensive. An example concerns plans for CCS in Wyoming, the leading US coal state. Wyoming mined 41 percent of US coal in 2020 and coal-fired plants produced about 85 percent of the state’s electricity. With abundant coal resources and good opportunities to store CO2 underground, Wyoming appeared to be an excellent candidate to use CCS. The state passed House Bill 200 in March 2020, directing utilities to produce 20 percent of electricity from coal plants fitted with CCS by 2030.
In response to the statute, Rocky Mountain Power and Black Hills Energy, Wyoming’s two major power companies, analyzed alternatives for their operations and provided comments to the Wyoming Public Service Commission in March 2022. But the comments were not favorable for CCS. Black Hills Energy determined that adding CCS to two existing coal plants would cost an estimated $980 million, or three times the capital cost expended to build the plants. Rocky Mountain Power stated that adding CCS to its existing plants was “not economically feasible at this time.”
Beyond cost, the amount of carbon dioxide that advocates say must be captured is vast. The amount of CO2 produced by industry is small in global terms, only about five percent of what nature releases into and absorbs from the atmosphere every day. But the amount of industrial CO2 produced is still huge in human terms.
For example, an empty Boeing 747 jumbo jet weighs 412,300 pounds (187,000 kg). Its maximum fuel weight is 433,195 pounds (196,494 kg), more than the empty weight of the aircraft. During fuel combustion, two oxygen atoms are taken from the atmosphere and combined with each carbon atom. For each kilogram of jet fuel burned, 3.16 kilograms of carbon dioxide are created.
Consider the Drax Power Station in North Yorkshire, England, the third-largest power plant in Europe, which has been converted to using two-thirds biomass fuel. The plant is experimenting with CCS to reduce emissions. Each day, the plant uses about 20,000 tons of wood pellets delivered by 475 railroad cars. Picture the volume that these railroad cars would carry and then more than double it to get an idea of the amount of CO2 to be captured and stored each day.
The world’s heavy industries use vast amounts of coal, natural gas, and petroleum. Ammonia, cement, plastics, steel, and other industries produce billions of tons of materials each year for agriculture, construction, health care, industry, and transportation. Capturing, transporting, and storing CO2 from these processes would involve trillions of dollars and many decades of investment.
The International Energy Agency calls for 9 percent of the world’s CO2 emissions to be captured and stored by 2050. Today we have a mix of 39 major and minor capture facilities in operation. The IEA estimates that 70 to 100 major capture facilities will need to come online each year until 2050 to achieve this goal. It’s unlikely that even 20 percent of the goal will be achieved, despite hundreds of billions of dollars in spending.
This article originally appeared at Master Resource
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