Wednesday July 06, 2022

Carbon capture

October 23, 2018

The latest Intergovernmental Panel on Climate Change (IPCC) report lays out a rather grim set of observations, predictions and warnings. Perhaps the biggest takeaway? That the world cannot warm more than 1.5 degrees Celsius (1.5 degrees Centigrade) over pre-industrial levels without significant impacts.

If the world warms a mere half a degree more than that, hundreds of millions of people could face dire consequences – namely famine, disease, and displacement – from things like rising sea levels and increased drought and flooding.

Time for action to stem the worst effects of climate change is quickly running out, however. If we’re to stay below or within range of that 1.5 degrees Centigrade threshold, global carbon emissions must decrease by about 45 percent from 2010 levels by 2030, and we must reach zero carbon output around 2050. Energy sector carbon emissions, however, are still growing, not shrinking.

What’s more, it won’t be enough to simply slash carbon emissions to zero. As the latest IPCC report points out, we’ll also need to suck up to 1 trillion metric tons of carbon from the biosphere over the 21st century.

If large-scale CO2 extraction is to be effective, many experts warn that such efforts will need to begin in earnest within the next few years. But carbon extraction is far from a primary feature of climate discussions among policy makers. Glen Peters is a climate researcher at the CICERO Center for International Climate Research in Oslo. He told Norway’s VG News:

There are media reports of images showing wind turbines and solar panels. It is well and good, but meeting the goals in the Paris agreement requires so-called negative emissions – removing much of the CO2that has already been released. The subject is little talked about, but politicians will eventually come to understand what a huge task it is.

The other problem is that the technologies currently capable of sucking CO2 from the air are still being developed and are too expensive to be commercially viable, which leaves experts hamstrung as to whether this is the right approach to stall global warming. In a 2016 paper published in Science, Peters and Kevin Anderson, the deputy director of the Tyndall Centre for Climate Change Research at the University of Manchester, called the assumption that these technologies and concepts will work to scale in time a “moral hazard.”

However, Roger Aines, chief scientist of the energy program at Lawrence Livermore National Laboratory, disagrees. The “magnitude of the problem” is such, he told Truthout, that “we have to get started” with widely employing technologies capable of removing CO2 from the air. “It’s the question of how to get started,” he said, “that occupies a lot of my time.”

For the past few decades, talk of CO2 filtration has largely surrounded carbon capture and storage (CCS). In essence, CCS is when CO2 is removed at the source of the emission, like a power plant smokestack, before being repurposed.

There’s a reason CCS is crucial when it comes to carbon extraction: It’s far easier to filter out CO2 at the source than it is directly from the air. That’s because the ratio of CO2 in, say, a coal power-plant exhaust flue (about 10 percent CO2) is that much higher than the ambient air (where CO2 is about 0.04 percent). The problem is that most CCS technologies are, at the very best, carbon neutral, meaning they squirrel away as much CO2 as they emit in the first place. However, if we’re to remain under that 1.5 degrees Centigrade threshold, we’ll need to employ large-scale use of negative emission technologies – in other words, technologies that extract more CO2 from the atmosphere than they release.

This article has been excerpted from: ‘Carbon Capture: What We Don’t Talk About When We Talk About Climate Change’.