“The path of sound credence is through the thick forest of skepticism.” – George Jean Nathan
Imagine, if you will, a green chalkboard. In the upper left corner is written CH4, the chemical formula for natural gas, and in the bottom right is everybody’s favorite molecule, CO2. In between these extremes—sloping downward and to the right—are the words oil, coal, and wood, in that order. What our chalkboard illustrates is a gross approximation of the extent to which the carbon atoms embodied in those materials are already burned (i.e., oxidized), and by extension how much residual energy can be extracted from these feedstocks by burning them further. In essence, it serves as a proxy for energy density.
Since CH4 has no oxygen atoms and every carbon is surrounded by four hydrogens, it is not burned at all and is rich in potential energy. Oil has fewer hydrogens per carbon atom and barely any oxygen, so it is only slightly more burned than CH4. Coal contains less hydrogen still and a fair bit of oxygen, so it is measurably more burned than oil. Wood is replete with oxygen-rich celluloses and other complex natural polymers, putting it below coal on our chalkboard. Finally, CO2 is saturated with oxygen, and so the carbon in it is fully burned. It is a thermodynamic sink.
It follows from this rudimentary chemistry lesson that burning wood emits more CO2 per unit of energy produced than burning coal, that coal is worse than oil, and that oil is worse than natural gas. The same can be said about other undesirable byproducts of combustion, as wood and coal in particular contain all manner of contaminants that do not burn very well. As an instructive contrast, natural gas burns so cleanly and efficiently that we use it for cooking indoors with nary a thought given to ventilation, but starting a campfire in the middle of your living room would be, well, kind of nuts. The clouds of smoke that blanketed much of North America last year as a result of forest fires in Canada are testimony to these obvious empirical truths.
It has come to our attention that some people are concerned about how much CO2 humans emit into the atmosphere. These people – who seem to work mainly for governments, at non-profits, and on university campuses – would prefer to restrict activities that increase carbon emissions, since failing to do so will apparently lead to a parade of unrecoverable catastrophes. They seem quite settled in this view, and it is logical to assume that, given the choice, they would advocate moving up and to the left on our chalkboard. Such logic makes what has occurred in the UK and other countries across Europe rather curious. We turn to a story from 2018 for some early details (emphasis added throughout):
“The 12 cooling towers at the Drax Power Station have dominated the flat North Yorkshire countryside since the plant was built to burn coal from local mines in the ’60s. It’s the largest power plant in the UK, and for years it served as a visible reminder of how essential coal has been for the country. But five years ago, Drax started switching from burning coal to burning wood.”
In the intervening years, four of Drax’s six generators at its Selby facility have been converted to burn wood, while the two remaining coal-fired generators have been removed from service. The station currently produces about 4% of the UK’s electricity and sources much of its wood from abroad, especially Canada and the US. The rationale for this exercise is downright perplexing:
“Drax started transitioning its units off of coal and onto wood fuel because the UK government is putting tight restrictions on carbon emissions to help fight climate change. This year, the country announced its plan to cease burning coal for electricity entirely by 2025. And under EU [and UK] law, biomass is classified as a source of carbon neutral energy.”
By government decree, burning wood no longer produces more CO2 than burning coal. It apparently produces no CO2 whatsoever, at least according to the carbon counters in Brussels and London—surprisingly convenient for those in the burning business instructed to care about CO2 emissions. Not actual CO2 emissions, of course, just the ones the government has decided to count, which seems to us like a fine example of the difference between science and “the science.”
By what rationale is this environmental sleight-of-hand justified? Will clear-cutting forests be our salvation from calamity? Let’s break out a chainsaw and head to the forest to find out more.