The anaerobic digestion (AD) sector has seen ‘significant growth’ in the UK, a new industry survey reports.

The ‘Annual Survey of the UK Organics Recycling Industry’ (ASORI), published today (11 December) by the Waste & Resources Action Programme (WRAP) in partnership with the Renewable Energy Association’s Organics Recycling Group (REAORG), the Anaerobic Digestion and Bioresources Association (ADBA), and the Environmental Services Association (ESA), provides new data for 2013 regarding the capacity and output of the AD industry.

Reporting growth throughout the sector, the survey reveals a 55 per cent increase in overall operating capacity; a 51 per cent increase in the quantity of organic materials processed; and a 36 per cent increase in employment within the industry.

Industry growth

According to the study, the total number of operational AD facilities has increased by 34 per cent, up from 87 plants in 2012 to 117 in 2013. As a result, the overall operating capacity of the AD sector has grown by 55 per cent, from 2.07 million tonnes to 3.20 million tonnes.

These trends are reported across the board, with each of the three main industry segments (commercial; industrial; and on-farm) reporting an increase in operating capacity of around 50 per cent.

As a result of this growth in capacity, the overall quantity of organic materials processed by AD plants has increased by 51 per cent, from 1.69 million tonnes to 2.55 million tonnes.

Furthermore, the number of people within the UK finding employment in the AD sector has increased by 36 per cent, from 354 to 482 full-time equivalents.

Material breakdown

The report goes on to provide a breakdown of the different types of feedstock processed by AD plants in 2013.

Figures show that quantities increased for each of the different types of material processed: separated solid food; liquids; manures; and crops.

Food and drink waste continue to constitute the largest proportion of materials processed, with separated solid food at 38 per cent and liquids at 30 per cent.

Correspondingly, the largest source of feedstock was food manufacturers and processors (66 per cent of the material processed). The quantities processed from this source increased from 330,000 tonnes in 2012 to 820,000 tonnes in 2013.

Few AD operators find practice economically ‘valuable’

The report also presents new findings regarding the role and market value of digestate within the AD sector.

Over a million tonnes of digestate were applied to agricultural land in 2013, representing 98 per cent of the total quantity for which a use was reported.

However, the survey reveals that few AD operators are finding the practice to be economically valuable, with the reported market value of agricultural application averaging at a cost of £3.73 per tonne (ranging from a loss of £13 to a revenue of £3 tonne).

Mixed reactions

Speaking after the release of the report, ADBA’s Chief Executive, Charlotte Morton, commented: “WRAP’s annual organics recycling survey for 2013 highlights the strong growth of the AD industry over the past five years. Operational capacity has continued to surge forward in 2014 too, with our latest data showing that there are now 329 plants across all AD sectors, providing 386 megawatts of capacity for renewable electricity.

“The UK is already one of the European leaders on food waste AD facilities and technology, with over 80 plants in operation. But with only about seven per cent of our food waste recycled through AD the potential is far greater, and can only be delivered by government policy which supports segregated food waste collection schemes.

She added that if the UK were to recycle all the food waste which is unsuitable for consumption, the AD industry could be “five times bigger than it is today”, meet more than 10 per cent of the UK’s domestic gas demand, reduce carbon emissions by two per cent, “recycle essential nutrients for food production, and deliver new high value biotechnology products, such as biochemicals and bioplastics”.

However, Ian Wardle, Head of Organics and Energy at WRAP, said that the results were largely positive, stating: “It’s fantastic to see such positive results from this survey. The industry is turning a wide variety of wastes into valuable renewable energy and digestate that can be used by farmers as a fertiliser.

“Each year we are seeing the sector grow and this year’s data shows the AD industry is starting to make a marked contribution to the UK economy. Industry has always supported this survey and this year’s excellent response is testament to that.”

Read the ‘Annual Survey of the UK Organics Recycling Industry’ 2013.