Chief Scientific Adviser Sir John Beddington values SCI work on Anaerobic Digestion

Summary of issues

Summary of issues raised by participants at the conference 'Biorenewable Fuel and Fertiliser: - Realising the Potential'

On 24 March 2010 SCI held a conference at the Food and Environment Research Agency's facilities outside York entitled 'Biorenewable Fuel and Fertiliser: - Realising the Potential'. After considering the scientific, operational and financial aspects the delegates debated the subject. Their consensus was that anaerobic digestion (AD) has a huge potential for producing biorenewable fuel and biofertiliser but that this has not been realised because unnecessary rules have impeded financing and/or construction and because too little recognition has been given to the positive values of conserving nutrients.

Delegates wanted to see the government take a grip of this important area by taking the following actions: -

• Produce one simpler clearer regulation, based on outputs not on inputs or processes, for all biofertilisers (treated organic residuals) used on farmland - probably the Sludge Use in Agriculture Regulations (1989) plus the Safe Sludge Matrix and HACCP
• Define a support regime for biorenewable fuel that is guaranteed for 10 years, that does not inhibit co-treatment; again it should address outputs not inputs or processes. Support could be tapered or even nil but certainty for 10 years is needed in order to unlock capital investment
• Instruct the Environment Agency not to over-interpret legislation and to be proportionate as regards anaerobic digestion plants and their outputs considering all of the other ambient risks
• Make achievement of EU directive obligations, impact on the phosphate crisis and impact on climate change the determinants of policy and delete some of the gratuitous objectives of the previous government that have been a distraction. Again concentrate on outputs rather than inputs and processes.

The Government has not given sufficient attention to the phosphate crisis and to the contribution that converting waste to biofertiliser via AD can have on conserving the planet's phosphate and reducing the UK's reliance on importing primary phosphate. Today's phosphate mines will be exhausted before the end of the twenty-first century at the current rate of extraction. Phosphate is essential for all cells, and cannot be substituted because it is part of DNA and energy mechanisms. Many energy sources can substitute for fossil fuel but for phosphate there is no substitute. Society, the Government, agriculture and the food and bioresources industries need to be more aware of the critical importance of phosphorus conservation and recycling to land in bioresources and should actively support and encourage this to ensure long-term food security. The contribution to mitigating the phosphate crisis should be a fundamental consideration of all relevant policies.

AD is an especially valuable source of non-fossil energy because it is continuous base-load energy. Unlike solar, wind or waves it is not dependent on weather or time of day. Biogas (and more especially biomethane) can be stored so the energy supply can match demand. Government has given too much emphasis to discontinuous, weather-dependent sources.

The cost and difficulty of obtaining connections to the electricity (or gas) grids has been a hurdle as has the bias against biogas in the Feed in Tariffs and Renewable Heat Incentives.

AD projects are expensive and even the best do not break-even in less than 5 years (with renewable energy incentives factored in. Government has been too timid and vacillating about committing to renewables incentives. If they were reduced or not renewed/extended within 10 years of committing to an AD project, it could become loss-making. In this climate of uncertainty it has been difficult to secure finance for projects. If the government is going to incentivise/subsidise renewable energy it should commit to levels of incentive for realistic periods of time. Certainty will unlock capital. Biorenewable fuel and fertiliser is another area where Government introduced unnecessary complexity. Government has disincentivised co-digestion but co-digestion can enable sourcing a critical mass of feedstock within a viable distance, whereas mono-digestion can mean a much larger catchment to secure the critical mass. Co-digestion enhances the specific biogas yields of the substrates synergistically. Co-digestion at wastewater treatment works would enable use of existing assets – an important consideration given the financial deficit.

The Environment Agency (EA) has viewed the risk posed by AD plants disproportionately, which has increased planning and construction costs unnecessarily. For example the requirement to bund sites so that if the tanks were to burst their contents would be contained is not proportionate to the risk of such catastrophic failure. In general the EA should take a more proportionate approach and give consideration to the benefits as well as the risks.

The complexity, lack of clarity, cost and bureaucracy associated with the regulatory aspects of using digestate on land have been excessive and disproportionate to the specific risk and to the ambient risk. The Sludge Use in Agriculture Regulations supplemented by the Safe Sludge Matrix and HACCP has proved effective. It would be simpler and less confusing if this was consolidated into a revised regulation that covered the use of all treated organic residuals. A requirement for auditing to a British Standard (not PAS) would obviate the need for inspection fees, which were grossly excessive until recently.

The requirement for facilities burning 3MW or more of biogas to obtain permits under PPC legislation is another example of disproportionate action that has resulted in unnecessary cost and bureaucracy. This low limit is a distraction of EA resources and it is a barrier to increasing energy generation when a site is close to the threshold. 30MW would be more sensible.

The PAS110 (and PAS100) requirements are excessive for using treated organic residuals on farmland [or for land reclamation]. Some of the methods are unvalidated, i.e. their repeatability [within a lab] and more importantly reproducibility [between labs] is unknown. Some require a very long time period to complete, which means storage of treated material and/or could have significant recall implications. It would be better if they were replaced by methods, accredited to MCERTS. An expert industry/regulator technical group should rapidly agree the most appropriate empirical methods to be used; it would be best if this was done by the relevant Technical Committee of the British Standards Institution (BSI).

There has been excessive focus on requirements for, and categorisation of, inputs to treatment when it would be better to have requirements for the outputs of treatment. It is the outputs that impact the environment, not the inputs. The ingenuity and innovative capability of industry should be allowed to develop the best means of achieving the necessary output standards. The response of policy makers and regulators that an instrument has been subject to public consultation is no substitute for sound and objective drafting. Consultations are good but there are so many that there is overload except for those with a particular [vested] interest that justifies the cost of responding. Fewer, better, clearer, fairer instruments would be far preferable and would help to realise the potential for biorenewable fuel and biofertiliser.

Realising the huge potential for biorenewable fuel and fertiliser via anaerobic digestion has been hindered by

• Lack of clarity in requirements,
• Excessive difficulty regarding planning permission,
• Disproportionate permitting requirements that have resulted in excessive bureaucracy and cost,
• Lack of decision regarding incentives for renewable energy,
• Bias in favour of wave, solar and wind power to the detriment of AD,
• Lack of proportionality regarding risk management and
• Excessive interpretation of EU legislation compared with other member states that have moved further with AD.

These have combined to inhibit the commitment of capital investment in AD. With clearer more holistic thinking the potential of AD for biorenewable fuel and fertiliser could be realised, which would also reduce the UK's climate change emissions and advance the change from a disposal to a recycling society.