Carbon dioxide emissions in US drop to 20 year low. Why?

I mentioned this article from Slate.com briefly yesterday, but it’s worth putting on here as well as it does rather poke a bit of stick into the ribs of the local environMENTALists currently going nuts over the SA Government moratorium on fracking being lifted.

Carbon-dioxide emissions in the United States have dropped to their lowest level in 20 years. Estimating on the basis of data from the US Energy Information Agency from the first five months of 2012, this year’s expected CO2 emissions have declined by more than 800 million tons, or 14 percent from their peak in 2007.

The cause is an unprecedented switch to natural gas, which emits 45 percent less carbon per energy unit. The U.S. used to generate about half its electricity from coal, and roughly 20 percent from gas. Over the past five years, those numbers have changed, first slowly and now dramatically: In April of this year, coal’s share in power generation plummeted to just 32 percent, on par with gas.

It is tempting to believe that renewable energy sources are responsible for emissions reductions, but the numbers clearly say otherwise. Accounting for a reduction of 50 Mt of CO2 per year, America’s 30,000 wind turbines reduce emissions by just one-10 the amount that natural gas does. Biofuels reduce emissions by only 10 megatons, and solar panels by a paltry three megatons.

All of which further demonstrates the benefits of shale gas, not just for the South African economy, but also for the environment. And with Eskom currently building the  largest dry-cooled coal fired power station in the world at Medupi in Limpopo, which will burn through almost 15 million tonnes of coal each year for the next 40 years, it would be nice to have a safer, cleaner, more efficient yet viable alternative.