Climate Change: New Idea For Sucking Up CO2 From Air Shows Promise

The world is warming faster than ever before due to human-caused greenhouse gases inhaled into the air. These gasses trap heat from the sun and cause climate change, endangering life as we know it.

Scientists estimate that we must remove billions of tons of carbon dioxide annually from the atmosphere by midcentury in order to avoid dangerous levels of warming or restore Earth's ecosystems. It's an enormous task.

How it works

Scientists are seeking ways to stop carbon dioxide from escaping our atmosphere. One potential solution involves using machines that directly absorb CO2 from the air and store it underground in facilities. According to researchers, this new approach could be up to three times more efficient than existing methods.

Scientists and fossil fuel companies had until now only been able to capture carbon dioxide in factories through chemical filters that absorb it from smokestack emissions. The idea was that this would save them fossil fuel consumption, as well as reduce greenhouse gases emitted elsewhere.

However, carbon dioxide is relatively dilute in the air. This makes it challenging for large machines to capture a significant amount without burning fossil fuels, which explains why direct air capture has been so slow to take off.

In the late 1990s, some scientists began exploring ways to pull carbon out of the air and store it safely for future generations. This technology, known as negative emission, could potentially help us combat climate change's worst effects, its supporters claimed.

Scientists have been striving for years to create a way of doing this, and many obstacles have stood in their way. But some companies have persevered regardless - some having achieved success and others not so much.

Climeworks, a Swiss company, has developed machines that draw air in and filter it for CO2 molecules. Once trapped, this CO2 is then injected deep underground where it permanently turns into stone.

There are also other companies trying to use chemicals to remove carbon. Some concrete producers are employing carbon dioxide in order to make calcium carbonate, which gets trapped within the concrete during curing.

Capturing and storing billions of tons of carbon is still far from being an adequate solution to the issue at hand. Nonetheless, some countries and corporations have begun exploring this possibility as a potential solution.

Why it’s important

Carbon dioxide, the gas that composes our atmosphere, is a greenhouse gas that warms the Earth. It plays an essential role in nature and human life by helping plants produce carbohydrates through photosynthesis - how we obtain food from sunlight.

As we burn fossil fuels such as coal, natural gas and oil for energy, we release vast amounts of CO2 into the atmosphere which is warming Earth's climate and altering ocean pH levels--a condition known as ocean acidification. As CO2 dissolves in ocean waters and reacts with water molecules, producing carbonic acid which lowers sea water's pH--a condition scientists refer to as ocean acidification.

Scientists have come up with several solutions to reduce atmospheric carbon. One major solution is stopping burning fossil fuels, which could potentially slow or even reverse global warming.

But there are cheaper methods of removing carbon from the air. One such technology is direct air capture (DAC).

The concept is straightforward: A machine draws air from the atmosphere, filters it out and traps CO2. Afterward, this captured carbon is injected into the ground beneath a coal or natural-gas mine for use as fuel.

Some companies, such as Climeworks of Switzerland and Carbon Engineering from Canada, have already tested this approach. Their plants claim to capture around one ton of CO2 daily.

However, these machines aren't cheap; they require enormous amounts of energy to filter and absorb the gas as well as pump it into the ground.

According to scientists at the University of Calgary in Canada, a better and cheaper option is bioenergy with carbon capture and sequestration (BECCS). This process takes biomass--like wood, grass or grains--and burns it for electricity production. The CO2 produced from this process is then removed from its smokestack and buried deep underground where it can be safely kept for an extended period.

Some countries, including the United States, have passed laws offering tax credits to firms that capture carbon - known as carbon capture, utilization and storage (CCUS). But this process is complex and expensive; its economics remain uncertain.

Who’s behind it

If the world wants to slow climate change, a novel concept for sucking up carbon dioxide from the air offers hope. If implemented, this technology could help humanity avoid a planet that's warming too rapidly and could become uninhabitable by the middle of this century.

The concept is straightforward: capture CO2 from the atmosphere and use it in ways that don't cause emissions. Possible applications include turning it into synthetic fuels and burning them, but this approach has its own issues.

First and foremost, carbon capture is costly and requires a great deal of energy. One analysis has determined that it takes almost as much energy to capture one ton of carbon this way as burning 100 gallons of gasoline.

Another issue is that if this technology isn't powered by renewable sources, it could add even more heat-trapping gases to the atmosphere than what is already present. This would make achieving climate goals much harder.

Some inventors contend it's best to collaborate with fossil fuel companies and their partners, such as oil and gas giants like ExxonMobil or Shell, who possess the infrastructure and know-how needed for building these facilities on a large scale. That means getting their approval to pipe captured CO2 into wells in order to boost production or sequester it underground.

Despite its shortcomings, this type of technology is becoming more and more popular among big tech and climate scientists. This enthusiasm has some environmentalists concerned.

But if the inventors can secure enough funding, their technology could help the world avoid some of the worst effects of climate change. They believe direct CO2 removal is necessary if we want to reduce greenhouse gas concentrations by 1.5 degrees Celsius below pre-industrial levels, as scientists say is necessary in order to avert catastrophic climate change.

The world's biggest tech companies are now investing heavily in this concept, with the inventors hoping to persuade government representatives that this is no crazy idea. In fact, they may even receive a $12 million grant from the federal Department of Energy as part of their efforts.

How it could work

Arizona State University researchers have devised an efficient new method for extracting carbon dioxide from the atmosphere that may be up to three times more effective than current methods.

Scientists are becoming increasingly worried about the consequences of global climate change, and a recent study has estimated that we must remove between 100 billion and one trillion metric tons of CO2 from the atmosphere to prevent warming below 1.5 degrees Celsius. These emissions come mainly from factories around the world due to burning fossil fuels such as oil or coal.

However, it's incredibly challenging to prevent new emissions. The only way to slow global warming is by reducing our carbon dioxide output; however, if that proves ineffective, we will have no choice but to find a way of absorbing any extra heat created.

Scientists began exploring ways to absorb carbon from the air rather than from factory smokestacks. They identified several promising technologies, including one called bioenergy with carbon capture and sequestration (BECCS) which could bury a significant amount of captured CO2 underground in a process similar to how plants absorb gas through photosynthesis.

However, BECCS' primary drawback is that it only works in dry climates. Furthermore, its gaseous output has a much lower carbon concentration than expected - ideal for fertilizing greenhouses but not ideal for sequestering large amounts of CO2.

Lackner and his team are exploring another approach, known as "direct air capture," or DAC. This involves exposing sorbents such as resins or polymer strips to air in machines that resemble giant airlocks.

Energy-intensive, but achievable with renewable energies or natural gas. Plus it's scalable - meaning it can be installed anywhere with access to power and enough infrastructure to store captured gas underground for later use or other purposes.

Lackner remains optimistic that his technology can help the planet avoid catastrophic levels of warming. Indeed, he and his team have earned two awards for their work: one from the University of California and another from the National Science Foundation.