Despite all the efforts made by delegates to the climate summit in Glasgow, the world continues to spiral toward catastrophic levels of global warming. Some countries and corporations are now turning to new technologies in order to remove carbon from the atmosphere.
The US Department of Energy (DOE), today announced a bold plan to make these technologies, known as carbon dioxide removal (CDR), cost-effective and scalable. It is called the Carbon Negative Shot initiative. The agency hopes to reduce the cost of CDR to less than $100 per ton over the next decade so it can be used on a large enough scale to remove billions, or gigatons of tons of carbon dioxide from our atmosphere.
This is quite a bit of CO2 pollution.
This is quite a bit of CO2 pollution. According to the DOE, removing one gigaton carbon dioxide from the atmosphere would remove the pollution from approximately 250 million light-duty vehicles in the US within a year. The DOE still has a lot of work to do before CDR technologies are fully developed.
CDR refers to a set of strategies that draw down CO2 in order to prevent it from trapping heat inside the atmosphere. Some of this can be done by nature, as plants and trees pull CO2 from the air. Direct air capture technology is also available that mimics this process, but it is not yet widely deployed.
The US will need large-scale, direct air capture plants to draw down heat-trapping pollutants. Iceland's largest direct air capture plant was launched earlier this year. It can only extract 4,000 tons of carbon dioxide each year. This is roughly equivalent to 790 passenger cars emitting carbon dioxide per year. According to the International Energy Agency (IAEA), there are currently only 19 air capture plants in the world. They only have the ability to capture a small fraction of the DOEs goals.
The main reason tech has not advanced further is because of cost. Microsoft and other companies pay around $600 per ton of Iceland's CO2 that it captures. In 2020, the company produced 11,164,000 metric tonnes of carbon dioxide. Microsoft would have to spend almost $6.7 billion to eliminate its pollution for a single year at $600 per tonne.
The main reason tech has not advanced further is because of cost.
However, cost is not the only problem. The CO2 is trapped in direct air capture plants using chemical or filter solutions. The chemical solution or filter must be heated to extremely high temperatures, between 100 and 905 degrees Celsius, to release trapped CO2. This requires a lot of energy. According to Nature Communications' 2019 study, machines that extract carbon from the air could end up using as much of the world's energy supply as 25% by 2100. It could be contributing to the problem it is trying to solve if that energy comes from fossil fuels. It is technically still difficult to use only renewable energy to reach the extreme temperatures needed for direct air capture. The DOE announced today that it intends to account for emissions from the building and operation of the removal technology.
The DOE also wants to ensure that CO2 is stored in places where it can safely be monitored for at most 100 years. To prevent humanity from getting worsened by climate change, it should be kept in a secure location for longer periods of time. The Iceland plant uses CO2 to pump underground. Companies behind the project claim that it can be stored underground for thousands of years. This type of storage is possible because Iceland's volcanic activity has produced basalt rock with a relatively young, porous nature.
New pipelines and carbon storage infrastructure will cost billions of dollars.
The US will need to locate similar locations and transport it via new pipelines. Biden's infrastructure bill, which is getting closer to final voting, includes billions of dollars for new pipes and $3.5 billion for four air capture hubs. Carbon dioxide can be deadly if it is present in high levels.
Leading climate scientists have included carbon removal in their roadmaps to limit the severity of the climate crisis. Some progressive activists have criticized this, claiming that carbon removal is a distraction from the transition from fossil fuels towards renewable energy. Even experts who are optimistic about the future caution that it is not the main course of any plan to combat climate changes.
It's a supplement that can help reduce climate change. This is what David Morrow, the director of research at American University's Institute for Carbon Removal Law and Policy, said to The Verge when the Iceland plant went online in September. It can't replace cutting emissions.
The US, which is the second-largest CO2 emitter in the world, must still focus on alternative fuels to prevent future greenhouse gas emissions.
Similar: How the largest direct-air capture plant will remove CO2 from the atmosphere
