Crop feedstocks for AD: getting the facts

This week, Defra has published experimental statistics on the areas of non-food crops grown in the UK. This includes the areas of oilseed rape, sugar beet, wheat, miscanthus, short rotation coppice and straw crops grown in the UK for use as bioenergy. They can be found in full here, with information on anaerobic digestion in chapter four.

Some of the headline figures are:

  • Farm-based plants used 631,000t of inputs in 2012, of which 389,000t were crops
  • Forage maize grown for biogas used around 15,500 hectares in 2013, less than 10% of UK maize

The area of land used to grow maize for AD in 2013 was less just 0.24% of the UK’s croppable area. That around 60% of farm feedstocks are crops demonstrates the way that they are combined with wastes such as manure and slurry.

Overall, the industry has become increasingly dominated by waste feedstocks in recent years. We estimate plants treating municipal, commercial and industrial waste make up 75% of the industry’s installed capacity, without even taking into account some farm wastes.

Ensuring bioenergy sustainability is vitally important to government, as both the Committee on Climate Change and the Bioenergy Strategy rightly made clear. The industry therefore needs to engage with the evolution of sustainability criteria: our blog for members went into more detail about this process recently. The sustainability calculator is already providing a useful tool, for example showing as its default value that maize AD produces electricity at 115 gCO2/kWh, compared to a grid average of almost 500 gCO2/kWh.

However, sustainability is about more than a greenhouse gas number. The ways in which crops for AD can be integrated into farming practice have other benefits, including improving soil quality, reducing the need for chemical inputs and complementing food production. AD feedstocks can be integrated into crop rotations rather than turning whole areas over to energy production, and nutrients are returned to land through digestate rather than wasted. There are details and examples of this in our briefing document here.

We are in the process of producing best practice guidance on growing crop feedstocks for AD, which we hope to publish in the next few months. This will demonstrate how farmers can generate wider environmental benefits using AD crops, and avoid environmental risks.


Posted in: ADBA News, Industry News, Members' press release, News for Members, Policy updates, R&D Updates

Tags: bioenergy, bioenergy sustainability, crops, DECC, farming, Matt Hindle, sustainability criteria