What about “clean coal” or other carbon capture technologies?

The term “clean coal” refers to the possibility of continuing to use coal as a fuel, but without allowing the carbon dioxide it produces to enter the atmosphere. A similar idea can be applied to natural gas and oil (petroleum) as well. So, is this a good idea? This question is the topic of a lot of debate. The basic idea is pretty simple:

• The primary reason that fossil fuels are a problem for global warming is because of the carbon dioxide they release when burned. (A secondary reason is methane leakage from oil and gas fields.)
• Therefore, if we could somehow trap, or “sequester,” the carbon dioxide before it goes into the atmosphere (for example, by injecting it deep into the ground), then we could keep burning fossil fuels without contributing to global warming.

This idea, often called carbon capture and sequestration is very attractive to many people, particularly those who work in the fossil fuel industry, because it would in principle allow us to stop the threat of global warming without needing to transform our entire energy economy. Indeed, for this reason, there are dozens of research projects around the world, many with demonstration power plants already in operation, that aim to develop this technology.

However, this approach is controversial, because the technology seems to have at least two major drawbacks, even if it works:

• First, while it would in principle address global warming, it would not automatically address other forms of air and water pollution associated with fossil fuels — and this pollution is estimated to lead to at least 5 to 10 million premature deaths each year around the world.
• Second, most envisioned strategies for carbon capture and sequestration would require adding equipment — and therefore expense — to existing fossil fuel power plants. While this would surely be worth the cost if it stopped global warming, the added cost would create incentives for unscrupulous power plant operators to cheat and not use the technology properly. This type of problem has already occurred with existing requirements for pollution controls, and without strong legal regulation and enforcement, it could easily undermine the goal of reducing emissions.

Still, global warming is such a critical problem that we should be prepared to embrace any technology that can help us stop it. Research into carbon capture and sequestration is continuing, and it may yet prove to be part of the solution to global warming.