The Anaerobic Digestion and Biogas Association (ADBA) has released a comparison table to show the benefits of anaerobic digestion (AD) over hydraulic fracturing ('fracking') in response to a recent Institute of Directors (IoD) report that supported the method.

The IoD report, 'Britain's Shale Gas Potential', garnered recent media attention for its recommendation of shale gas (extracted via fracking) as a viable means to shore up Britain's energy security. The report cites lower prices, reduced carbon emissions, resource longevity, and job creation as arguments in favour of fracking.

Fracking, a gas-extraction method that has been controversial due to concerns about risks of causing minor earthquakes and water pollution, has been particularly controversial in the UK as the government has shown signs of increased support for the method.

"Shale gas development does not magically solve all the UK's energy issues”, says the IoD in the report, ”A mix of power sources is vital, and domestic shale gas is unlikely to account for a majority of the UK's electricity generation, or even of its gas usage. But it could and should play an important role."

The ADBA has argued, however that renewable energy such as AD biogas from organic waste is a better alternative. In their comparison, the ADBA highlight the following distinctions between biogas from AD and shale gas from fracking:

• Both methods could create up to 35,000 jobs
• AD biogas could supply 10 per cent of the UK's annual domestic gas demand indefinitely (as long as there is a constant supply of organic waste), and shale gas could produce 10 per cent of demand for 103 years if estimated reserve levels are correct and extraction is economically feasible
• Biomethane could be worth £2-3 billion to the UK economy
• Biogas is a low carbon fuel that produces 11g of CO2 per kilowatt hour (kWh), while shale gas is a fossil fuel that produces around 400g of CO2 per kWh
• Biogas is a renewable option for gas vehicles and heavy goods vehicles (HGVs), which can also be fueled by shale gas
• Biogas can be generated constantly, whereas shale gas has limited reserves
• Byproducts of biogas are digestate biofertiliser and water that can be returned to water courses. Byproducts of shale gas from fracking are wastewater and chemicals that cannot be recovered.
• Biogas risks are managed under HSE and EA guidelines, whereas fracking runs the risk of water pollution, releasing large quantities of methane gas into the atmosphere, and low magnitude earthquakes.

"The government and industry should fully embrace biogas, a constantly generated, renewable gas, and one of the few renewables that could be scaled up and rolled out in time to meet our 2020 climate change targets", said Charlotte Morton, Chief Executive of ADBA.

"Going forward the UK will have to take a portfolio approach to energy supply in order to provide security. There is no one technology that can deliver our energy needs, but renewable gas has significant potential and brings benefits above those that natural and shale gas can deliver. It needs to be the UK's priority."

The government is anticipated to give the go-ahead to increase fracking in the UK, when it publishes a new gas strategy later this year

ABDA’s comparison comes ahead of a WRAP report stating that AD is driving recycling in the organics sector.