shale gas is the same as ‘normal’ natural gas: methane, and is the cleanest — least polluting — of all the fossil fuels
shale gas resources are vast and push up the world’s total reserves by almost half (around 650 trillion cubic metres or 23,000 trillion cubic feet)
countries like the USA can reduce their dependence on ‘foreign’ energy imports
used wisely, it could provide a lower-carbon energy ‘bridge’ as people wean themselves off fossil fuels and on to renewables like wind and solar
Coal not only makes more than double the carbon dioxide — CO2 — pollution for the same amount of heat, but adds a toxic cocktail of other pollution too (sulphur dioxide, radioactive ash, mercury). So although coal is a filthy fuel, it powers around 40 per cent of the world’s electricity generation and looks set to increase.
And the bad…
fracking creates serious leaks of methane, a greenhouse gas which is around 25 times more powerful than CO2. Eventually methane breaks down to CO2 and water vapour, both major greenhouse gases themselves
it can cause small earthquakes
it needs vast amounts of water plus sand and many different chemicals. The sand and chemicals aid in keeping the fractures open so the gas can come out
some of this fluid may contaminate groundwater (drinking water underground) and the waste fracking fluids — called ‘flowback’ — can cause more pollution because they bring up from deep below stuff like salt, hydrogen sulphide gas and even radioactive radium
fracking also makes it possible to get methane out of deep coal seams and can be used to extract more oil from old oilwells and oilfields. Using more fossil fuel is not good when you think about pollution and greenhouse gases. So no country should be looking for more but, you guessed it, they are doing. Why? Russia has huge amounts of oil and gas, much of which was piped to western European countries and brought the Russians much-needed money to pay for the war they had started with their neighbouring country, the Ukraine. And war is the worst thing humans can do to our poor battered biosphere. You human kids have enough to worry about now that we know that the oil and gas companies have known and lied about for decades that fossil fuels were poisoning us. Did they warn everyone? No. They were making so much money. And now they are back to make even more money fracking for methane. <iframe width=”707″ height=”530″ src=”https://www.youtube.com/embed/JkhX5W7JoWI” title=”Money – Pink Floyd + Lyrics” frameborder=”0″ allow=”accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture” allowfullscreen></iframe>
because the USA has increased its use of shale gas to generate electric power by such a large amount, it is now using much less coal. Sounds good, doesn’t it? But that coal is still being mined and sold to Europe which doesn’t have so much gas. So as carbon emissions have gone down in the US, they’ve gone up in countries like Britain and Germany which have started guzzling cheap American coal. It’s an unfortunate fact that electricity-generating companies will always burn whatever fossil fuel is cheapest. For now, shale gas is cheap in the US whilst coal is cheapest in much of Europe. So the mining of coal — the filthiest but cheapest fuel for most countries — continues to go up. This ‘law of the jungle’ where the cheapest fuel is always burned to make the cheapest electricity (never mind the pollution) is, to be fair, not entirely the fault of the generating companies. It’s that no-one wants to pay more than they have to for energy and so they look for the cheapest supply.
“If natural gas displaces coal, then fracking is good not only for the economy but also for the global environment. But if fracked gas merely displaces efforts to develop cleaner, non-carbon, energy sources without decreasing reliance on coal, the doom and gloom of more rapid global climate change will be realized.” Extract from The Facts on Fracking by SUSAN L. BRANTLEY and ANNA MEYENDORFF, New York Times, March 13, 2013
Gaseous confusion Not to be confused with gasoline, often just called ‘gas’ too but gasoline is a liquid fuel – also called petrol – which is what most cars run on. Confusing, isn’t it!
What is ‘natural gas’? It is a gas called methane made up of chemical elements carbon and hydrogen. That’s why it’s called a hydrocarbon. This gas burns very well in air and so people use it as a major source of energy
also called a ‘well’ (as in ‘oilwell’)
Shale is a sedimentary rock. It started off as mud when it formed millions of years ago, usually on an ancient seafloor. Over time and with the weight of all the later sediments (like sandstone or limestone) above it, it has turned into a rock; a process called lithification.pp
About drills Drills are tools which bore deep holes in the rocks in order to get at valuable stuff like water, oil or gas. The drill has a special cutting ‘bit’ on its end and is connected by an ever-longer set of metal rods back up to the surface. Here, machines spin the rods round to make the bit far below spin and so grind its way through the rocks. As the drill bores deeper, engineers at the surface drilling rig fit more rodsdrill
What is casing? Casing in made of a series of steel pipes which line the well to prevent the escape of fracking fluids and gas. The steel casing is usually made stronger and more leak-proof by injecting concrete
The fracking fluid has to be separated out and stored in tanks or ponds so that it can be treated by having pollutants removed
International Energy Agency figures
Most of the commonly-used ones are harmless but the list runs into many hundreds, many of which are toxic. The fracking companies tend to be secretive about their particular injection fluid ‘recipes’ so it’s hard to know what’s going on