Deploying renewable energy, electric vehicles, and energy efficiency programs, etc. is crucial to combating climate change. However, such smart energy solutions are not enough to meet decarbonisation goals set under the Paris Climate Change agreements and other ambitious climate action targets being set by different governments across the globe for the near future. Carbon Capture is regarded as an alternative approach to reducing CO2 emissions.
Carbon Capture and Storage (CCS) is a three-step process, involving: capturing the carbon dioxide produced by power generation or industrial activity, such as steel or cement making; transporting it; and then storing it deep underground. One Israeli-German green-tech company named High Hopes says its carbon capture and storage solution will not only help mitigate climate change but effectively reverse it.
Currently, carbon capture and storage are very expensive. Switzerland’s Climeworks currently operates in 14 locations and has large factories processing ambient air and separating out the carbon, but its solution costs between $600 and $1,000 per ton and doesn’t predict a price drop below $250 per ton. There are billions of tons of greenhouse gases in the air. The price plus the amount of carbon needed to be extracted isn’t feasible. The current cost of carbon capture stems from the long, intensive process that goes into it. First, large fans are used to draw in air. Then carbon dioxide is captured on the surface of a filter. The capsule is closed and heated to 80℃-100℃ and releases a concentration of CO². The CO² must then be compressed to around 70 atmospheres and sent underground for geosequestration—where over years, the compound will turn into stone. Eran Oren, Chief Scientist of High Hopes, figured out a way to circumvent the costs of this not-so-efficient solution - using balloons and high altitudes.
High Hopes leverages the colder temperatures in high altitudes to scale carbon capture, sending balloons into the sky to capture the carbon and bring it down to the ground. Carbon typically freezes around –80℃, and once it is frozen into dry ice – similar to snowflakes – capturing the gas is much easier. The temperatures at high altitudes can be as low as minus –70℃. This means the payload of the company’s balloons doesn’t need to work as hard to freeze the carbon and extract it from the atmosphere as it would on the ground, where temperatures are much warmer.
Once the load is full, the pressure and warming temperatures on the way back to the ground turn the carbon back into condensed gas that can be sent straight for geosequestration. And the company is able to do this with off-the-shelf technology. The balloons and carbon-capture rigs needed already exist – they just need to be put together and sent into the air.
High Hopes’ promise seems fantastic, and it’s interesting to see if they’ll manage to fulfil their vision. However, to some experts, the basic promise of carbon capture is a dangerous illusion supported by the energy industry. Prof. Mark Z. Jacobson of Stanford University, for example, claims that as the world careens toward tipping points, we can’t afford to grasp at imaginary straws. According to this approach, there is a conceptual problem because the whole goal of carbon capture is to reduce one chemical, which requires energy, so no matter what technology is made, it will always be worse than replacing the coal or gas in the first place. He argues that the world should not waste resources on carbon capture, but rather just stop emitting and pour the resources into replacing all fossil fuel use with renewable sources.