The Pros And Cons Of Biomethane and Shale

What is the future of powering the UK? Is there one form of energy that will dominate? These are the kinds of questions that are often discussed on occasions such as the 2017 Future Energy Scenarios event, where the use of shale gas and biomethane were debated.

LPG storage tanks provider, Flogas, analyses both these energy sources to discover their benefits and drawbacks — and to find out if either could be the saviour of UK energy in the future…

What is biomethane gas and how can it help the UK energy user?

With biomethane gas, the UK may significantly boost its chances of slashing its carbon footprint in the future. This is because the gas occurs naturally from the anaerobic digestion of organic matter, which can be sourced from manure, organic waste, sewage and both dead animal and plant matter. Biomethane is also a sustainable method of sourcing gas to sewage treatment plants. This means those in the industry will not need to rely on extracting natural gas from the ground, as the two are the same type of gas.

Already, we are enjoying the advantages of biomethane gas in the UK. For example, Severn Trent Water was successful in opening a facility at its Minworth Sewage Treatment Works in 2014. Here, biogas from the anaerobic digestion process is converted to be used in domestic gas supply. This biomethane can then be injected into the National Gas Grid. With 1,200 cubic metres of biogas converted into 750 cubic metres of biomethane per hour, this plant was the biggest gas-to-grid facility in the UK when it launched.

“As part of the sewage treatment process, sewage sludge is produced. At Minworth we feed this to our 16 anaerobic digesters, or ‘concrete cows’, which work like giant cow’s stomachs to digest the waste material to produce energy in the form of gas.

“Currently, we use 40 per cent of this energy to make electricity, but more can be done – that’s where this new process comes in. With treatment, gas from sewage is made clean enough and at the right consistency to be injected into the gas supply network to power homes in the area. It’s local gas produced from local people,” said Severn Trent Water’s renewable energy development manager. A year after the launch of the new Minworth Sewage Treatment Works gas-to-grid facility, well-known supermarket chain Sainsbury’s made history by making its Cannock superstore the first to be powered entirely by the food waste created by the retailer.

Here were the supermarket chain’s operational policies before the change to its Cannock store in 2015:

• Unsold food turned into animal feed.
• Unsold food still suitable for human consumption given to charities.
• Surplus unsold food delivered to Biffa’s advanced anaerobic digestion facility in Cannock.

To create electricity, food delivered to Biffa’s advanced anaerobic digestion facility is broken down to create biomethane gas. When Biffa and Sainsbury’s collectively realised that the Cannock superstore and the advanced anaerobic digestion facility were within close proximity, they installed a 1.5km cable between the pair of buildings so that the plant could provide an efficient supply of renewable electricity to the supermarket.

Sainsbury’s has said that it could save about £140,000 in a year using this method, despite forking out around £280,000 of investment to complete the project (i.e. to set up the power cables, switch gears and cover all legal fees). Statistics like these are certainly in favour or advocating the use of biomethane in the UK.

What is shale gas and how can it help the UK energy user?

Shale gas is heavily debated in the media, with many people protesting against its extraction (i.e. fracking). On one side, the UK government has argued that shale gas could give us increased energy security, growth and jobs. However, the argument is that the method for extracting shale gas — which involves water being injected into ‘shale’ rock formations at a high pressure to extract gas —could harm the environment and is too costly.

The notion that fracking extends our reliance on fossil fuels is also argued, as is the risk of it polluting water and causing to earthquakes. Steve Mason, of cross-party pressure group Frack Free United, said: “This Tory government is backing fracking and forging on with a ludicrous dirty energy policy. It is time for them to wake up and listen to their own reports, the voice of the public in areas under threat and halt all fracking activity now.”

If you’re anti shale gas, perhaps you will change your mind when you explore its success in the US. It wasn’t too long ago that the US was importing large amounts of oil and gas. That changed when the country discovered the effectiveness of extracting shale gas, with the nation is now self-sufficient and exporting gas.

Unfortunately, the UK is in a precarious situation regarding energy. We import more than half of the gas we need from overseas sources. However, a report by the British Geology Society published in 2012 suggested that there is a resource estimate of around 1,327 trillion cubic feet found throughout the UK.

Also weighing in on the argument is Jim Ratcliffe, the CEO of Ineos’ — a company with a licence to frack in the UK in an area measuring one million acres. He said: “The future for manufacturing in the UK will look quite gloomy if we don’t exploit shale. I can’t see otherwise what is going to arrest the decline in British manufacturing.”

Could shale gas or biomethane gas save the day for the UK? Perhaps the answer to the UK’s energy woes remains unclear.