Two centuries of Carbon dioxide, a powerful greenhouse gas, has been released into the atmosphere by burning fossil fuels.
As that CO2 builds up it can be used to create more. Heat traps near Earth’s surface, causing global warming. The atmosphere is so rich in CO2 that many scenarios do not show it. Ending emissions alone won’t be enough to stabilize the climate — humanity will also have to Reduce CO2From The air.
The U.S. Department of Energy recently launched a new GoalTo scale up direct air captureThis technology uses chemical reactions. Capture CO2From the air. Federal funding for carbon capture is often criticized because some see it as an excuse to continue using fossil fuels. However, carbon removal in some way will likely occur. It is still necessaryIPCC reports confirm this.
Technology to remove carbon by mechanical means is in development and operational at A very small scaleThis is partly because current methods are too expensive and time-consuming. But new techniquesThis year, they are being tested to see if they can lower energy demand and costs.
We reached out to an Arizona State University professor Klaus Lackner, a pioneer in direct air capture and carbon storage, about the state of the technology and where it’s headed.
What is direct carbon removal and why is this important?
My interest in carbon management began in the early 1990s. I was struck by the fact that carbon builds up in the environment. It takes nature Many thousands of Years to remove that CO2, and we’re on a trajectory toward Much higher CO2Concentrations that are far beyond what humans have ever experienced.
Humanity can’t afford to have increasing amounts of excess carbon floating around in the environment, so we have to get it back out.
Not all emissions come from large sources. Power plants or factoriesThis is where we can capture CO2 in its natural form. So we need to deal with the other half of emissions — from cars, planes, taking a hot shower while your gas furnace is putting out CO2. This is the process of taking CO2 out from the atmosphere.
How direct air capture works.
Since CO2 mixes quickly in the air, it doesn’t matter where in the world the CO2 is removed — the removal has the same impact. Direct air capture technology can then be used to store or use the CO2.
It is also important to consider the method of storage. Storing CO2 for just 60 years or 100 years isn’t good enough. If all that carbon is gone 100 years from now, then all we did was take care ourselves. Our grandkids will have to do it again. In the meantime, the world’s energy consumption is growing at about Two percent per year.
One of the complaints about direct air capture, in addition to the cost, is that it’s energy-intensive. Can this energy consumption be reduced?
Running fans to draw in air, and heating the CO2 to extract it are two of the largest energy-consuming activities in direct air capture. Both can be reduced in energy consumption.
For example, we stumbled into a material that attracts CO2 when it’s dry and releases it when wet. It was easy to expose it to wind and it would fill up with CO2. We could then make it moist and it would Let the CO2 go!This system uses far less energy that other systems. The CO2 pressure rises even more when heat is added from renewable energy. This creates a CO2 gas that has water vapor mixed with it, from which we can extract pure CO2.
We can save even more energy if the capture is passive — it isn’t necessary to have fans blowing the air around; the air moves on its own.
My lab is working on a method that will do this. Mechanical trees. They’re tall vertical columns of discs coated with a chemical resin, about five feet in diameter, with the discs about two inches apart, like a stack of records.
The discs’ surfaces absorb CO2 as the air passes through them. After about 20 minutes, the discs become full and sink into a barrel below. To release the CO2, we send in steam and water. Now we have a low pressure mixture of CO2 and water vapor.
We can recover most heat that was used to heat up the box so the amount of heating energy required is very low.
We can reduce energy consumption by using moisture and then use renewable energy to replace the rest. This does require water and dry air, so it won’t be ideal everywhere, but there are also other methods.
Can CO2 be stored safely for long-term storage?
In the 1990s, I was a leader of a Los Alamos group that began to work on the concept. The world can actually put CO2 away permanently by taking advantage of the fact that it’s an acid and certain rocks are base.
When CO2 reacts to calcium-rich minerals, it forms solid carbonates. By Mineralizing the CO2Like this, we StoreThere is an almost limitless amount of carbon that can be stored permanently.
For example, there’s lots of basalt — volcanic rock — in Iceland reacts to CO2It turns it into solid carbonates in a matter of months. Because Iceland stores CO2 for the rest the world, it could sell carbon sequestration certificates to the rest.
You can also find huge underground reservoirs that are the result of oil production in Texas’ Permian Basin. There are large saline-rich aquifers. Equinor, an energy company, has been collecting CO2 from a gas processing facility and storing it in the North Sea, about a kilometer below sea level. A million tons of CO2 a year since 1996, avoiding Norway’s Tax on CO2 emissions. The underground storage we have available for mineral sequestration will be far greater than what we ever need to store CO2. The question is how much can we convert into a proven reserve.
Direct air capture can also be used to get within a few meters. The carbon loop — meaning CO2 is reused, captured, and reused again to avoid producing more.
People currently extract energy from carbon from fossil fuels. You can convert CO2 to synthetic fuels — gasoline, diesel, or kerosene — that have no carbon in them by mixing the CO2 with green hydrogenCreated with renewable energy
This fuel can be shipped through existing pipelines and stored for years. You can generate heat and electricity in Boston on winter nights using energy from West Texas last summer. A tankful of “synfuel” doesn’t cost much, and it’s more cost-effective than a battery.
The Department of Energy established a new goal to lower the cost of carbon dioxide removal to US$100/ton and scale it up quickly within a decade. What needs to happen to make it a reality.
DOE scares my hell because they seem to think the technology is ready. After neglecting the technology for 30 years, we can’t just say there are companies who know how to do it and all we have to do is push it along. This technology is still in its infancy.
Climeworks is the largest commercial company that does direct capture. It sells CO2 for around $500 $1,000 per ton. That’s too expensive. However, at $50 per tonne, it’s possible. I believe we can achieve it.
The U.S. consumes around seven million tonnes of CO2 per year. merchant CO2 — think fizzy drinks, fire extinguishers, grain silos use it to control grain powder, which is an explosion hazard. The average price is between $60 and $150. A market exists if the average price is less than $100
You need a regulatory framework to say that we demand CO2 is stored. Then, the market will stop capturing kilotons of carbon dioxide today and start capturing gigatons.
Where do you see this technology going ten years from now?
I see a world where fossil fuels are gradually phased out, but that has the mandate to capture and store all CO2 long-term.
Our recommendation is that carbon should be removed from the ground when it comes out. You should put away one ton of carbon from coal, oil, and gas if you produce one ton. It doesn’t have to be the same ton, but there has to be a Certificate of sequestrationIt is certified that it has been properly disposed of and must last at least 100 years. If all carbon is certified from the moment it comes out of the ground, it’s harder to cheat the system.
Uncertain is the extent to which industry and society will work together to become carbon neutral. It’s encouraging to see companies like MicrosoftStripe Purchase carbon creditsCertificates to remove carbon dioxide and willing to pay high prices
It can take a decade to get new technology to work, but if there is an economic incentive, things can move quickly. In 1951, the first commercial jet was made. They were commonplace by 1965.
This article was originally published on The ConversationKlaus Lackner, Arizona State University Read the Original article here.