Anaerobics display

Written by: Geraldine Faulkner | Published:
Future Biogas's AD plant in Norfolk

ADBA chief executive Charlotte Morton explains anaerobic digestion’s current and potential environmental, social and economic benefits, and how these might be better realised through more concerted government policy and action

People often ask what led me to become chief executive of the Anaerobic Digestion and Bioresources Association (ADBA). If you ask the average person in the street about anaerobic digestion, you’re likely to be greeted by a blank face and will spend the next 10 minutes explaining it to them – AD certainly doesn’t benefit from the same simplicity of concept and media coverage as other low-carbon technologies such as wind and solar. But when I first became familiar with AD, I discovered a multi-faceted technology that has the potential to transform the waste, renewable energy, agricultural and transport sectors, as well as make a huge contribution to mitigating climate change – all through simply recycling the organic waste that we all produce and discard on a daily basis.

What AD can do

Put simply, AD turns organic wastes (including food and plant waste, crops, slurries and sewage) into a range of invaluable resources:

Green gas in the form of biomethane that can be directly injected into the gas grid, where it can be stored

• Renewable heat and baseload electricity when put through a combined heat and power (CHP) unit

• Renewable transport fuel in the form of biomethane

• Low-carbon, organic fertiliser in the form of digestate

• Other bioresources that can be used to make bioplastics and chemicals.

Alongside these physical outputs, AD offers a range of benefits to the UK economy: 30,000 (mostly rural) jobs by 2030 if the industry continues to grow; reducing the UK’s carbon emissions by 4%; restoring the UK’s depleted soils through use of nutrient-rich digestate; supporting farmers; meeting government recycling targets; improving the UK’s food and energy security; and a huge opportunity to export UK expertise in AD to what has the potential to be a £1tn global biogas industry.

Despite the seemingly endless list of benefits that AD offers, government support for green gas to date has been lukewarm, and has been unable to allow AD’s full potential to be recognised or anywhere near realised. So what are the barriers holding the industry back from faster growth, and what needs to happen for these to be overcome?

An AD strategy from government

As with other low-carbon technologies, AD has benefitted in recent years from government support in the form of the Renewable Heat Incentive (RHI), the Feed-In Tariff (FIT), the Renewables Obligation (RO), and to a lesser extent the Renewable Transport Fuels Obligation.

This support has allowed the number of AD plants in operation across the UK to surpass 540 and its capacity to reach over 708MWe-e, enough to power 850,000 homes. The biomethane-to-grid sector in particular has seen the largest growth in the biogas industry over the past three years, with almost 90 plants now feeding green gas into the grid.

And yet the short-term and uncertain nature of this support means that the growth the industry has seen recently is unlikely to be sustained over the coming years without a further boost from government. The RHI still offers a good rather than excellent financial incentive for biomethane-to-grid, while the FIT is likely to be closed to new applications sometime in 2018.

The RO is already closed to new applicants and in terms of biomethane for transport, the lack of certainty over the price that Renewable Transport Fuel Certificates can be sold for is still a huge impediment.

So we need to be more proactive in convincing government that AD is a valuable investment for the taxpayer. A key opportunity lies in Theresa May’s flagship Industrial Strategy, designed to boost productivity and reinvigorate the UK’s diminished manufacturing sector.

ADBA is working closely with the Department for Business, Energy and Industrial Strategy (BEIS) and partner organisations to be part of two of the bespoke sector deals (bioeconomy and agriculture) that are likely to be struck in areas of strategic importance to UK industry.

We are also pushing for biogas to play a central role in BEIS’s Bioeconomy Strategy and Clean Growth Plan, key long-term strategies that are as important to the industry as day-to-day financial incentives.

Mandatory separate food waste collections

Figures from the Waste and Resources Action Programme (WRAP) show that the UK produces as much as 10 million tonnes of post-gate food and drink waste per year.

While a proportion of this is avoidable and should either not be wasted in the first place or should be redistributed to people and animals where safe and appropriate, the most effective way to recover the valuable resources locked up in the rest of this food and drink waste is to recycle it through AD.

This is only possible, however, if food waste is separated from other residual waste at point of collection. Of the 4.6 million tonnes of food waste collected each year by local authorities, only 12% is currently recycled.

Mandatory separate food waste collections exist in Scotland, Wales and Northern Ireland, but still not in England, where the vast majority of waste is produced. ADBA has with others been calling for some time for mandatory separate food waste collections in England to help reduce waste in the first place (evidence shows that separating food waste makes people realise how much they are wasting) and allow that which cannot be eaten or redistributed to be recycled through AD. The government has tasked the Environment Agency with promoting observance of the waste hierarchy (and we argue it should be enforcing it), but until Westminster gets serious about recycling food waste, it will fail to practise what it preaches.

Promoting best practice

AD plants, like all energy infrastructure, face the challenge of winning over local (often rural) communities in order to gain planning permission, and local residents often raise issues such as odour, noise, large amounts of road freight, and the possibility of accidents stemming from AD plants.

To help address these issues, ADBA is working with partners across the industry to develop a best practice scheme to help AD operators meet the highest environmental, safety and operational standards and maximise their performance.

This will help drive up standards across the board and give all necessary stakeholders, from government and regulators through to investors and local communities, the confidence that the growth of the AD industry is a welcome development both nationally and locally.

Research and innovation

While the UK AD industry grows bigger and better every day, and its total benefits mean that it offers the best return on investment of all renewable technologies, based on its energy output alone it is still failing to compete on cost with other more established renewable technologies such as offshore wind and solar.

AD has the potential to be cheaper than coal and provide more energy than nuclear, but to date has only delivered a fraction of this potential. Industry and academia have jointly identified the need for targeted, collaborative research to enable a step change in the rate of development of AD globally, and while a range of highly effective research projects and networks already exist, we need to build further on their success in a different way in order to help deliver the wide range of benefits that AD offers, which we know are achievable.

It’s for this reason that ADBA is joining with five of the UK’s top universities to support the establishment of an interdisciplinary Centre for Anaerobic Biotechnology
and Bioresources Research to bring together academics and industry to deliver this step change and put the UK at the heart of the global biogas industry. The UK already has world-class expertise in this field and could be a global leader, exporting expertise and equipment worth £5bn per year while creating close to 60,000 UK jobs.

Sustaining momentum

There is no doubt that AD will have an increasingly key role to play in the UK economy over the coming years, whether through decarbonising heat, providing clean fuel for HGVs and buses, providing support for farmers in a post-CAP (Common Agricultural Policy) world, or, most likely, a combination of all the above and much more.

Even as the amount of waste we produce is reduced (as it should be), a rising population means there will still be huge quantities of waste that need to be recycled in order to recover the valuable resources within and create a truly circular economy.

So while AD will increasingly come to be seen as an absolute no-brainer and critical to meeting global climate-change targets and the UN Sustainable Development Goals, it’s important that this still fairly young industry continues to be nurtured today so that it can fully blossom and deliver the full range of benefits that we as a society so desperately need. Here at ADBA we’ll continue to work with partners to make the case for anaerobic digestion until it gets the attention it deserves.

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