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The AD revolution starts here

News stories in our tabloids rarely reflect the benefits delivered by food waste and anaerobic digestion (AD). A Daily Mail headline last month, ‘Slopbuckets farce: UK-wide scheme to turn leftovers into energy only creates enough power for one small town’, prompted WRAP chief executive Liz Goodwin to brand the article ‘misleading’.

But one year on from the launch of Defra’s AD action plan, there is plenty to celebrate.

The growth of the technology during the past five years has been phenomenal. From a handful of facilities in 2007, there are now 48 waste-fed facilities processing over one million tonnes of food waste a year. Ninety councils collect food waste separately and a further 98 offer other forms of food and garden waste collections.

In the past year alone, more than 100 facilities have received planning permission, the number of facilities on the ground has increased by one third and the installed capacity has doubled.

‘The financial support available has changed from capital investment to subsidies for renewable energy and loans’

Defra’s AD action plan brought together the technology’s champions across the sector.

There are eight action areas and 56 actions. Almost 40% of those actions have already been delivered. Those who are involved in the delivery of the actions really believe the technology offers a massive business opportunity for UK plc. AD can and is creating ‘green growth’ - not just for farmers, recycling businesses and councils, but also manufacturers and power suppliers.

The AD business case is also becoming increasingly attractive. With landfill tax inching ever upwards - currently £64/tonne - the gate fee for food waste at AD sites is hovering around the competitive £40/tonne mark.

For local authorities, AD offers a triple win: satisfying residents, reducing costs and increasing recycling. For the Government, AD and its outputs offer not just part of the waste solution, but also the small yet important role in creating renewable energy.

Farmers, landscapers and regeneration businesses also have significant rewards to reap. Digestate or biofertiliser - the most significant output from AD - is an excellent alternative to conventional fertilisers.

Analysis shows that high levels of nitrogen and other essential nutrients required by crops are readily available from digestate. This means it can be used as a direct replacement for conventional nitrogen fertilisers. This is good news when fertiliser prices are spiralling ever upwards and digestate is available at a fraction of the price.

For investors, AD offers potential good and safe returns. The key word here is ‘potential’ because the biggest hurdle to overcoming investor uncertainty is guaranteeing feedstock contracts. But increasing numbers of businesses are showing interest in separate food waste collections.

A lack of understanding from the investment community can sometimes feel like hitting a brick wall, but that wall is slowly being dismantled. WRAP has funded demonstrations of food waste collections from businesses which will soon be rolling out across nine regions of the UK.

WRAP’s £10m AD Loan Fund has already supported Malaby Biogas in Wiltshire. The Government’s commitment to increase the energy from waste produced by AD is further demonstrated by the new Green Investment Bank, which recognises the value of AD bids. And there are external drivers too.

There is an increasing need for household and business food waste collections. This is partly because it makes economic sense to collect and process food waste and partly because customers want to do the right thing.

More than half of councils are now collecting and processing food waste in one form or another. And the devolved Governments are getting behind this drive too.

Under the new Scottish Waste Regulations, all business premises in Scotland that produce more than 50kg of food waste a week will be required to separate this for collection by January 2014. Those producing between 5kg and 49kg per week will be asked to follow this lead by January 2016. 

Local authorities in Scotland will also be required to offer a separate food waste collection to at least 80% of households.

Food waste is a key priority in Wales too. Every council offers a separate food or food and green waste collection; currently around 90% of households in Wales benefit from such a service.

In England, the Department for Communities and Local Government’s Weekly Collection Support Scheme may enable even greater numbers of local authorities to collect food from households. Despite the tabloid headlines, WRAP research in 2008 found 78% of those with a food waste collection were ‘satisfied’ with this service.

There is a huge amount of guidance on the technical aspects of food waste collections and how best to communicate with residents. WRAP has always said that food should be collected each week.

One of the challenges for processing facilities is managing the available feedstock, particularly in busy periods or during poor weather which can affect the regularity of deliveries, and speed of processing.

Frozen food waste must be thawed out first, but digesters need ‘feeding’ regardless of wintery road conditions. Despite these logistical challenges, AD infrastructure is now firmly on the map.

Growth in AD has been phenomenal in the past decade, with public money increasingly being made available to develop it. The support available has changed from capital investment to subsidies for renewable energy and loans. This is a strong indication of confidence in the sector. At a time of global economic uncertainty, the public sector is putting its money where its mouth is, so to speak, demonstrating commitment to resource efficiency and AD.

Businesses also need marketing plans, technical support, equipment and business advice. WRAP provides a great deal of this support to the sector for free.

Its ‘Doctor AD’ support has just enabled the UK’s fifth certification in PAS110 to be awarded to Langage Farm near Plymouth.

As part of a commitment to develop and grow a sustainable and profitable AD industry, WRAP is also looking for innovative solutions to two specific issues.

Its ‘Driving innovation in AD’ projects look to optimise processing and product manufacture for all scales of AD, while reducing the costs and complexity of small- scale AD. WRAP currently has 19 projects in development and plans to report on progress before the autumn.

Building the infrastructure is all very well, but the UK’s industry needs safe and secure markets too. Developing quality standards such as PAS100 and PAS110, along with quality protocols (QPs) for compost, digestate and AD, has been an essential part of WRAP’s work in recent years, enabling wastes to be seen as products.

Later this summer, the compost QP will be updated to ensure that the specifications remain valid and in line with market expectations and technical capabilities within the sector.

WRAP is also working to develop a matrix for biofertiliser to help make better use of digestate.

Field trials are also crucial to demonstrating the ‘on-the-ground’ benefits to users. WRAP’s most recent trials with potatoes showed increased yields of 10-15 tonnes per hectare compared with unfertilised crops.

This demonstrates the real value of digestate - WRAP estimates the fertiliser value of the digestate in this trial to be worth more than £80 per hectare. If all food waste generated in the UK was sent to AD, the nutrient content of the resulting digestate would have an approximate value of £50m, based on recent fertiliser prices.

So one year on from Defra’s AD action plan and seven years on from having just two AD facilities in the country, there are now more than 3.7 million tonnes of waste processing capacity available. This has the potential to generate 60MW of electricity or power for more than 100,000 homes.

We have come a long way. For the best economic benefits, waste prevention needs to be prioritised. But the currently available feedstock is likely to grow in coming years, as businesses of all types look for more cost-effective and greener waste solutions.

An opportunity

The UK produces 15 million tonnes of food waste every year. Just over seven million tonnes of this comes from households, with 60% being ‘avoidable’. But 2.8 million tonnes of this is ‘unavoidable’, made up of tea bags, egg shells, bones, banana skins, orange peel and so on. This means, no matter what, that 2.8 million tonnes of unavoidable food waste will still be ‘up for grabs’.

WRAP prioritises waste prevention in line with the waste hierarchy while stimulating the recycling industry to develop viable markets for the unavoidable food waste.

And there is likely to be more of it available for collection and processing from this summer following WRAP’s new Hospitality and Food Service Agreement. This voluntary agreement for quick-service restaurants, pubs, hotels, schools, prisons and many more aims to increase the rate of food and packaging waste being recycled, sent to AD or composted to 70% by the end of 2015.

AD action plan steering committee in full

WRAP, the Anaerobic Digestion and Biogas Association, the Renewable Energy Association, the Environment Agency, Defra, the Environmental Services Association, the National Centre for Bio-Renewable Energy, Fuels and Materials, the Chartered Institution of Wastes Management, the Royal Agricultural Society of England, Water UK, the CLA, the National Farmers’ Union, the National Grid, UK Skills, the National Energy Foundation, the Low Carbon Vehicle Partnership, the Department of Energy and Climate Change, the Department for Communities and Local Government, the Department for Business, Innovation and Skills and the Department for Transport.

Marcus Gover, director of closed loop economy at WRAP

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