The oil and gas industry can be rightly blamed for many problems, but an unexpected one is the development of ugly new words in the English language, and ‘fracking’ must be near the top of the list. It’s short-hand for ‘hydraulic fracturing’, a procedure that wrings gas out of rocks that don’t want to let it go.

The supply of gas has recently become very important to many nations as they seek secure energy sources, rather than depending on Russia and the Middle East.

At the same time, demand has risen for domestic heating, for fertilisers and as a key raw material in the chemical industry. Additionally, gas produces less CO2 than coal or oil for the production of electricity, so finding more has become significant.

Normally, gas occurs in the small spaces in permeable rocks, often trapped in certain geological formations, and once tapped it migrates very easily up the well to the surface.

However, the most accessible gas fields have now been exploited and attention has diverted to those where the gas is very reluctant to move, such as shale rocks made of very fine clay-like particles with few gaps, and methane from coal beds.

In both these cases there is a physical assault on the rocks, to prise them apart and then keep them propped open to allow the gas to gather and migrate. Not only is this energy intensive, so increasing the CO2 produced, but it can have unfortunate side effects for those living nearby.

Opening up the gas in shale beds 10,000ft down means pumping in water, foam, a range of chemicals, some explosives, and sand grains, at pressures of over 8,000lbs per square inch, to break up the rocks and allow the gas out. The consequences of this brutal approach can be wide-ranging.

Occasionally there will be well blow-outs, areas of surface subsidence and even earth tremors, but the main problem is to do with contamination of the water supply, often with carcinogens and heavy metals. It has been known for water to light and burn!

There is considerable concern in the north-east USA about the impact on local communities with numerous legal challenges to the development of more fracking. It is so serious that Congress has commissioned a formal enquiry into the safety of this technology.

There is less ‘fracking’ in Europe, though at the moment France has put any such development on hold, while in the UK there are plans to use this technique just south of London.

Providing more gas from the anaerobic digestion of our kitchen waste and sewage would seem to be a less damaging way of securing supplies in the future.