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Recycling Carbon?

Filed under: — stefan @ 9 May 2016

Guest commentary by Tony Patt, ETH Zürich

This morning I was doing my standard reading of the New York Times, which is generally on the good side with climate reporting, and saw the same old thing: an article about a potential solution, which just got the story wrong, at least incomplete. The particular article was about new technologies for converting CO2 into liquid fuels. These could be important if they are coupled with air capture of CO2, and if the energy that fuels them is renewable: this could be the only realistic way of producing large quantities of liquid fuel with no net CO2 emissions, large enough (for example) to supply the aviation sector. But the article suggested that this technology could make coal-fired power plants sustainable, because it would recycle the carbon. Of course that is wrong: to achieve the 2°C target we need to reduce the carbon intensity of the energy system by 100% in about 50 years, and yet the absolute best that a one-time recycling of carbon can do is to reduce the carbon intensity of the associated systems by 50%.

The fact is, there is a huge amount of uncritical, often misleading media coverage of the technological pathways and government policies for climate mitigation. As with the above story, the most common are those suggesting that approaches that result in a marginal reduction of emissions will solve the problem, and fail to ask whether those approaches also help us on the pathway towards 100% emissions reduction, or whether they take us down a dead-end that stops well short of 100%. There are also countless articles suggesting that the one key policy instrument that we need to solve the problem is a carbon tax or cap-and-trade market. We know, from two decades of social-science research, that these instruments do work to bring about marginal reductions in emissions, largely by stimulating improvements in efficiency. We also know that, at least so far, they have done virtually nothing to stimulate investment in the more sweeping changes in energy infrastructure that are needed to eliminate reliance on fossil fuels as the backbone of our system, and hence reduce emissions by 100%. We also know that other policy instruments have worked to stimulate these kinds of changes, at least to a limited extent. One thing we don’t know is what combination of policies could work to bring about the changes fast enough in the future. That is why this is an area of vigorous social science research. Just as there are large uncertainties in the climate system, there are large uncertainties in the climate solution system, and misreporting on these uncertainties can easily mislead us.

It’s fantastic that web sites like Real Climate and Climate Feedback re out there to clear some of the popular misconceptions about how the climate system functions. But if we care about actually solving the problem of climate change, then we also need to work continuously to clear the misconceptions, arising every day, about the strategies to take us there.

Anthony Patt is professor at the ETH in Zurich; his research focuses on climate policy


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