It is surprising how many politicians seem to place gas, in particular shale gas, in the same category as wind and solar for the purpose of renewable electricity generation.
Although natural gas converts to electricity more effectively than coal, with efficiencies of 56% versus 45%, gas is a fossil fuel. With shale gas its leakage into the atmosphere during production may render it’s overall effect on global pollution more deleterious than coal.
It should be remembered that when one tonne of coal is burned 2.8 tonnes of CO2 is released. When one tonne of natural gas is burned 2.6 tonnes of CO2 is released. The fact that coal is measured in tonnes and gas in cubic meters or energy content is irrelevant. The chemistry and the maths allows us to compare the pollution content.
We, the people inhabiting the globe have a problem on our hands. The CO2 content of our atmosphere stands at 400 parts per million by volume (PPMV) whereas our species emerged when the concentration stood at 270 PPMV. This concentration is at it’s highest point that it has been at in the last 4 million years.
“Anatomically modern humans evolved from archaic Homo sapiens in the Middle Paleolithic, about 200,000 years ago. The emergence of anatomically modern human marks the dawn of the subspecies Homo sapiens sapiens, i.e. the subspecies of Homo sapiens that includes all modern humans. The oldest fossil remains of anatomically modern humans are the Omo remains, which date to 195,000 (±5,000) years ago and include two partial skulls as well as arm, leg, foot and pelvis bones.” Quoted from Wikapedia as referenced in A and B below.
So for the entire period of human history the concentration of CO2 in the earths atmosphere was constant at 270 PPMV. Is this a coincidence?
The atmospheric condition that existed during our entire emergence as the dominant species is gone. Was it decisive in our triumph over all the other inhabitants of the planet?
Another way of posing the question is “can we afford to take the risk that we depend on the lower concentration of CO2 (270 PPMV) in the atmosphere?”
As a business guy, who lives or dies by managing the risks facing the business, the answer is easy. If I had a choice there is no way I would run this risk.
A^ “Fossil Reanalysis Pushes Back Origin of Homo sapiens”. Scientific American. February 17, 2005.
B^ McDougall, Ian; Brown, Francis H.; Fleagle, John G. (17 February 2005). “Stratigraphic placement and age of modern humans from Kibish, Ethiopia“. Nature 433 (7027): 733–736. doi:10.1038/nature03258. PMID 15716951.