Breaking The Grid, Part 2B: Mitigating Pollution That Has Already Occurred
Part 2B: Carbon capture, reforestation, etc.
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The previous articles in this series show where we stand today, both in terms of how we generate electricity, and the pollution generated by various economic sectors. There are 4 main ways to change this picture:
Generate and store energy more cleanly (Part 2A, previously published)
Mitigate pollution that IS generated (This article, Part 2B)
Use energy more cleanly
Improve energy efficiency, ideally in all sectors, so less energy is needed.
A future article, Part 2C, will address the last two.
Technologies for Mitigation
Carbon Capture, Utilization, and Storage (CCUS):
The definition of CCUS from the International Energy Agency is:
CCUS involves the capture of CO2 from large point sources, such as power generation or industrial facilities that use either fossil fuels or biomass as fuel. The CO2 can also be captured directly from the atmosphere. If not being used on-site, the captured CO2 is compressed and transported by pipeline, ship, rail or truck to be used in a range of applications, or injected into deep geological formations (including depleted oil and gas reservoirs or saline aquifers), which can trap the CO2 for permanent storage.
CCUS technologies also provide the foundation for carbon removal or "negative emissions" when the CO2 comes from bio-based processes or directly from the atmosphere. …
Various efforts are underway, but you can see from the following quote and figure (Reference 1) that it is not nearly enough for net-zero emissions (NZE):
There are around 35 commercial facilities applying CCUS to industrial processes, fuel transformation and power generation, with a total annual capture capacity of almost 45 Mt CO2. CCUS deployment has been behind expectations in the past but momentum has grown substantially in recent years, with around 300 projects in various stages of development across the CCUS value chain.
Project developers have announced ambitions for over 200 new capture facilities to be operating by 2030, capturing over 220 Mt CO2 per year.
Where Will CCUS Processes Be Used?
Power and industrial plants in a post-combustion process to prevent released CO2 from entering the atmosphere
Production of hydrogen and CO2 in chemical processes, in a pre-combustion process. As noted in Wikipedia (Reference 7):
The technology for pre-combustion is widely applied in fertilizer, chemical, gaseous fuel (H2, CH4), and power production… The H2 can be used as fuel; the CO2 is removed before combustion.
Use in heavy industry (iron/steel/cement production) where there are few other options. Specific solutions might be needed for specific industries. In particular, Carbon Clean, a company selling CCUS for cement notes (Reference 8):
Cement is the world’s leading construction material — but it’s also one of the key drivers of climate change, responsible for around 8% of global CO2 emissions. Carbon capture is a vital technology to decarbonise cement manufacture, as up to 70% of CO2 emissions come from the chemical process of calcining calcium carbonate—which can’t be achieved with other methods.
The chemical process in “calcining” is for calcium carbonate, CaCO3, to be converted under high heat to calcium oxide, CaO, which is needed to make cement, with the release of CO2.
General removal from the atmosphere due to non-specific causes
What Will Be Done With The Captured Carbon?
Captured carbon can be used or disposed of in a variety of ways (Reference 2)
Today around 230 Mt of CO2 are used globally each year, primarily to produce fertilisers (around 125 Mt/year) and for enhanced oil recovery (around 70-80 Mt/year). Other commercial uses of CO2 include food and beverage production, cooling, water treatment and greenhouses. New CO2 use pathways include: fuels (using carbon in CO2 to convert hydrogen into a synthetic hydrocarbon fuel); chemicals (using carbon in CO2 as an alternative to fossil fuels in the production of some chemicals); and building materials (using CO2 in the production of building materials to replace water in concrete or as a raw material in its constituents.)
Most of these uses of CO2 add to global warming and pollution.
Capture Method 1: Direct Air Capture (DAC):
Direct Air Capture is a method for capturing CO2 from the air, instead of from a large point source like a power plant.
Pros & Cons:
DAC is more energy intensive than capturing CO2 from point sources because CO2 is more dilute in the general atmosphere. Therefore, access to renewable energy sources is extremely important.
DAC requires a site where the CO2 can be permanently stored underground. Alternatively, it could be transported to a facility that can use the CO2, in one of the applications described above.
Some of the operating conditions are still not completely understood – there are still investigations concerning how well capture works in drier or more humid or polluted air. According to the IEA in Reference 3, DAC is not on track for net-zero emissions:
Eighteen DAC plants are currently operational in Europe, the United States and Canada. All of these plants are small scale, and the large majority of them capture CO2 for utilisation – for drinks carbonation, for instance – with only two plants storing the captured CO2 in geological formations for removal. Only a few commercial agreements are in place to sell or store the captured CO2, while the remaining plants are operated for testing and demonstration purposes.
Elon Musk has offered a $100M prize for the best carbon removal strategies (Reference 6) through the XPrize foundation. According to IEEE Spectrum (Reference 5), a respected electrical engineering news magazine, $1M has been awarded to each of 15 different companies, using different types of technologies, who are finalists for the X Prize. The XPrize winner will be awarded $50M on Earth Day 2025:
The $50 million grand prize, to be awarded in 2025, is up for grabs for any team that can prove its technique will work at a scale of at least 1,000 tonnes/year.
That immense scale, as well as what happens to the CO2, will decide whether an approach can make a dent in the world’s nearly 36 billion tonnes of annual carbon emissions, says Gaurav Sant, director of UCLA’s Institute for Carbon Management
As you can see, the amount that might be pulled out of the atmosphere is a tiny fraction of the annual global carbon emissions.
Capture Method 2: Capture from Large Point Sources:
CCUS from large point sources, like power plants or chemical processing plants, comprises the major current use for CCUS. According to IEA in Reference 2:
Technologies to separate or capture CO2 from flue gas streams have been commercially available for many decades. The most advanced and widely adopted capture technologies are chemical absorption and physical separation; other technologies include membranes and looping cycles such as chemical looping or calcium looping.
The same reference also has a detailed summary of the various technologies that can be used, and their state of development/deployment, if you are curious.
Pros & Cons:
In addition to the processing requirements for capturing the carbon, there is additional infrastructure required to transport and store the carbon, as shown in the diagram above. Currently, the transportation alone might nullify much of any benefit of carbon capture.
Prior to researching this article, I had assumed that this technology would enable us to make substantial inroads quickly into reducing the carbon pollution from existing infrastructure. Surprisingly, I found out that the track record for CCUS projects is pretty terrible, according to the GAO as quoted in Utility Dive, an industry magazine (Reference 4):
The Government Accountability Office came out with a report last year where they particularly noted that CCS in the electric power sector has been a complete failure.
That report noted that DOE had provided almost $700 million to eight coal projects, “resulting in one operational facility.” NRG Energy’s Petra Nova facility in Texas received almost $200 million, according to the DOE report. The project, a partnership with JX Nippon, shut down in 2020 and, according to Reuters, missed its carbon capture goals by roughly 17% over the course of a three-year run.
Reforestation
Let us change the subject completely at this point, and discuss Reforestation, or the planting/nurturing of plant life in places where it had been previously destroyed. This is of course not new. But we need to list it as a major method that should be aggressively pursued for mitigation of pollution that has already been generated.
Trees and plants have been the ultimate carbon capture technology, and wetlands are also now recognized as well. (Reference 12)
Silliman and van der Heide conducted the new study with scientists from the Netherlands’ Royal Institute for Sea Research, Utrecht University, Radboud University, the University of Groningen, the University of Florida, Duke University, and Greifswald University.
By synthesizing data on carbon capture from recent scientific studies, they found that oceans and forests hold the most CO2 globally, followed by wetlands.
“But when we looked at the amount of CO2 stored per square meter, it turned out that wetlands store about five times more CO2 than forests and as much as 500 times more than oceans,” says Ralph Temmink, a researcher at Utrecht University, who was first author on the study.
There is an organization dedicated to planting 1 trillion trees by 2030 (Reference 9). As their website states:
We are part of the World Economic Forum’s work to accelerate nature-based solutions in support of the UN Decade on Ecosystem Restoration (2021-2030), supported by funding from Marc and Lynne Benioff.
Preventing Deforestation
And of course, we should be PREVENTING deforestation before it occurs.
Please watch for our upcoming article about using wood products in a sustainable way, to help curtail the demand that fuels poor logging techniques. One recommendation it will make is to pledge to buy only FSC-certified paper products.
There are also efforts to protect the Amazon rainforest, such as the one directed by the World Wildlife Fund (Reference 10).
According to the Rain Forest Alliance (Reference 11):
A swath of rainforest the size of 40 football fields disappears each minute. According to Global Forest Watch, our planet loses tropical forestland equivalent to the size of Bangladesh every year.
Acting locally as well as globally is extremely important. Right here in NJ, there is the NJ Conservation’s Franklin Parker Preserve which comprises 16 square miles of a former cranberry farm that is being returned to native plantings.
Also in NJ, as of the date of this publication, there is a controversy concerning Overpeck Park’s Area IV in Leonia, about whether to restore this former landfill with native trees and hiking paths, or with a great lawn. Contact the Northern NJ chapter of the Sierra Club to become involved.
In your local area, stay informed about development that threatens to tear down forests, or wooded lots.
Summary
Mitigation technology using carbon capture has been largely ineffective, despite being around for a long time. Many of the uses of captured carbon will perpetuate, rather than mitigate, global warming and environmental pollution. There might be some situations in which CCUS can serve a useful function, but better criteria must be used in selecting those demonstration projects, in order not to waste investment on plants that will be shut down, and diverting that investment away from more effective uses.
Certainly, reforestation and wetlands preservation are wholly good and should be aggressively pursued, but they won’t be enough.
Preventing deforestation in the first place is even more important. Using wood products in a sustainable way, both commercially and in our private lives, is one way to do that.
Pay attention to state and local deforestation issues, as well as global issues.
Given the gravity of global warming, however, we may need to take all possible routes to decarbonize to meet the net-zero timetables.
References
1. International Energy Agency information on CCUS
2. International Energy Agency general information
3. International Energy Agency information on Direct Air Capture
4. Utility Dive, Robert Walton, Oct 24, 2022, “There is a place for natural gas on a zero-carbon grid: EPRI”.
5. IEEE Spectrum, Carbon-Removal Tech Grabs Elon Musk’s Check, 28 May 2022, Prachi Patel.
7. Wikipedia entry on Carbon Capture and Storage, section on Pre-Combustion,
8. Carbon Clean
12. SciTech Daily, 7 May 2022, Earth’s Most Efficient Natural Storage System: Land-Building Marsh Plants Are Champions of Carbon Capture
Last updated: 11 July 2023
Here's a Bloomberg story that updates the progress/lack of progress from COP28: https://www.bloomberg.com/news/articles/2023-12-11/cop28-boosts-carbon-capture-a-long-shot-fix-for-the-climate?cmpid=BBD121123_GREENDAILY&utm_medium=email&utm_source=newsletter&utm_term=231211&utm_campaign=greendaily