The terms “carbon offset” and “carbon removal” are often confused. But let’s be clear: carbon offsets don’t actually remove CO2 from the air. Purchasing offsets reduces overall emissions, so if you emit, say, one metric ton of carbon, then one ton is avoided somewhere else by building a wind farm or evading deforestation. But that original ton is still out there, wreaking havoc on our climate.
Carbon offsets can be a helpful way to acknowledge one’s carbon footprint and support underfunded renewable energy projects around the world, but they don’t necessarily promote the major behavioral changes we need to see to make a dent in climate change. Just offsetting our polluting behavior won’t get the job done. To reverse climate change and reach target emissions objectives, we need a drastic reduction in CO2.
Think about it this way: If you buy an airplane ticket, along with enough carbon offsets to counterbalance your flight, the emissions from that jet are still entering the atmosphere. The damage is still being done, since you’re not actually removing CO2 from the air.
But what if you can?
The Case for Removing Carbon
The Intergovernmental Panel on Climate Change (IPCC) has stated that in order to keep global warming below the Paris climate target of less than a 2°C rise in average global temperature, we need an array of mitigation efforts that include massive cuts to emissions, as well as literally removing carbon dioxide from the air. To reach that target, the IPCC has found that we need to extract some 670 billion tons of carbon dioxide from the atmosphere this century. Doing that requires a process called carbon removal, which comes in many different forms.
It can be accomplished via reforestation or improved forest management to remove carbon through photosynthesis and store it in tree biomass. It can be done by improving agricultural soil quality to sequester more carbon. It can also be achieved by direct air capture, which entails collecting CO2 from the air and either using that carbon to make new products like building materials, synthetic fuels, or plastics, or sequestering it in geologic formations.
Alex Rudee, manager for U.S. natural climate solutions at the World Resources Institute, says it’s virtually impossible to completely eliminate all greenhouse gas emissions from the economy, particularly in sectors like industry and agriculture. “That means, in a matter of just a few decades, we need to figure out how to remove as much carbon from the atmosphere as we put in — or even more,” Rudee says. “We already know how to do that through natural solutions like reforestation, but those solutions aren’t nearly enough on their own to get us to the level we need. Technological solutions will also be critical.”
A Swiss company called Climeworks is banking on direct air capture technology: sucking carbon from the ambient air and storing it in permanent underground geological reservoirs. The company is nearly finished building a new direct air capture and storage system at a geothermal power plant in southwest Iceland that’ll do just that.
Called Orca, the Iceland project uses fans to pull air in, a chemical reaction then filters out the carbon dioxide, which is stored underground and eventually turned into stone via a mineralization process run by Climeworks’ partner Carbfix. The facility is solely powered by renewable, geothermal energy. Orca’s goal is to capture 4,000 tons of carbon dioxide annually, making it the largest direct air capture unit and storage facility of its kind in the world.
But to really move the needle on climate change, that needs to be scaled way up.
Investing in R&D
President Biden’s current infrastructure bill calls for $35 billion to be invested in research and development for climate change reduction, including carbon capture and storage. That’s huge, and a promising start for sure.
A study from the World Resources Institute estimates that we need to remove 2 billion tons of CO2 per year by 2050 to meet IPCC targets. In this case, we need massive financial investments in research from the federal government as well as the private sector. (WRI estimates we should be spending $6 billion per year specifically on carbon removal strategies.)
“We’ve been short on research and development and we need that investment, in particular with high-risk technology,” says Mario Molina, executive director of the climate advocacy group Protect Our Winters. “Things like direct carbon capture may not have that market appeal yet, but we’re not going to get breakthrough technology without R&D.”
More research is necessary before direct air capture can be done at scale. “Carbon capture is a more direct step of large-scale efforts to take greenhouse gasses out of the atmosphere,” says Max Boykoff, director of the Cooperative Institute for Research in Environmental Sciences at the University of Colorado Boulder. “You could argue that any tree anywhere is a small version of carbon capture, but when talking about carbon capture, most people are referring to much larger scale efforts.”
How Carbon Capture Differs from Carbon Offsets
This brings us back to the difference between direct air capture and carbon offsets. Carbon offsets are bought and sold on a trading system at a price determined by the market (which, most would argue, is much lower than the actual cost of carbon to society). It’s a huge and rapidly growing industry. The global carbon offset market could reach $50 billion by 2030, according to research from the Institute of International Finance.
“Offsets are useful to direct private investment into activities that are expensive to undertake and produce public benefits for climate change,” says Rudee, with the World Resources Institute. “The risk with offsets is when they create moral hazard, which is when companies, or governments, or individuals would rather continue to emit carbon into the atmosphere and pay someone else to create offsets rather than taking a hard look at how to reduce their own emissions.”
In other words: Carbon offsets can enable the world’s biggest polluters to continue polluting. “Carbon offsetting provides funding for underfunded projects worldwide that attempt to mitigate carbon emissions,” says Molina, of Protect Our Winters. “But some of the major drivers of offsets as a solution have been the fossil fuel industry.”
Carbon removal, on the other hand, means if you emit one ton of carbon, you eliminate one ton of carbon, resulting in net-zero emissions. If the CO2 is injected underground and stored permanently, as is the case with Climeworks’ Orca facility, then that CO2 is never making its way back into the atmosphere.
Direct air capture is still in its infancy (there are just more than a dozen facilities in the world using this technology). So there’s still work to be done to improve the cost effectiveness and energy efficiency of the process, but technological carbon removal will be needed in addition to natural removal. And with more investment and research, the better the process will become.
Though carbon offsets may buy us time, they alone are not a silver bullet solution to our climate crisis. Neither is carbon removal on its own, of course, but coupled with behavioral changes and wide-scale emissions reductions, direct air capture is a critical step in the process.
In order to restore Earth, we need to restore a healthy balance of CO₂. Carbon dioxide removal solutions can contribute to this. Climeworks operates multiple direct air capture plants and is currently building the world’s biggest climate-positive direct air capture plant! With Climeworks, everyone can remove their own carbon dioxide emissions from the air and then invite their friends to multiply the impact – for free.