Reviewing biowaste treatment in the UK

Professor Stephen Jenkinson has long experience in the waste and resources industry. He was the CEO of the PFI between Viridor Laing and Greater Manchester Waste Disposal Authority, the largest PFI in Western Europe establishing and managing waste management services for over 1 million households (2010-2018). He has held roles as Chairman of the Environmental Services Association (ESA) and the Chartered Institution of Wastes Management (CIWM) of which he is a Fellow and has served on the Board of the International Solid Waste Association. He is also a visiting Professor at Manchester Metropolitan University.

The views expressed in this paper are his alone.

1. Introduction

Like many of us I have had time during the lockdown to read and reflect on future waste management in the UK. I started thinking first about biowaste management because it is our largest waste stream but also the one during my years at VL that provided significant challenges. As the Department for Environment, Food and Rural Affairs (Defra) elaborates its policies in view of the second round of the consultation process into reforming resources and waste management in England due in 2021, I have tried to understand the challenges that the biowaste treatment industry is facing and the opportunity before them when food waste collections are mandated across England as they already are in Scotland, Northern Ireland and Wales.

Professor Stephen Jenkinson
Professor Stephen Jenkinson

The data are somewhat confused as Defra has just recently admitted [1] because we have data for the UK but often not separately for England, although that is where the Defra legislative mandate ends.  Therefore, this paper relates to the whole UK situation whilst realising that Defra legislative proposals relate to England and in some points refers more explicitly to the English situation.

Viewing the industry from my vantage point, I can allow myself to speak frankly and clearly. I hope this paper reflects that frankness. 

2. Executive Summary

  1. With five million tonnes of biowaste still being disposed of in landfills, it is urgent that we get biowaste into treatment for both greenhouse gas (GHG) abatement reasons and for the resources that biowaste can provide [2]. We cannot hope to achieve Net Zero Emissions by 2050 continuing like this. Government recognises this.
  2. Increasing biowaste treatment provides a unique opportunity for expansion of the anaerobic digestion (AD) and composting industries in the UK especially if the industry response to the challenge is collaborative and seeks high standards in inputs, treatment processes and outputs.
  3. However, the current focus upon the outputs from biowaste are heavily skewed towards the energy produced from AD plants. This author will argue in this paper that this imbalance is both unfavourable to the biowaste industry as a whole and to environmental outcomes for the UK.
  4. Current and it seems future policies will continue to incentivise the production of biogas/biofuels/biomethane rather than the solid component of biowaste treatment (organic carbon) [4]. Yet English soils have a rapidly declining organic carbon content that should be replenished in part by transforming biowaste into suitable soil improvers. This is a singular and strategic failure to future-proof English farming.
  5. Current outputs from biowaste treatment have a negative value and mostly do not find marketplaces. Energy production is achieved at several multiples of market prices whilst organic carbon is of low value due in part to low quality inputs and processing.
  6. Digestate produced from AD, unless further processed, can cause ammonia emissions during storage and when applied to soil may produce negative outcomes in terms of nitrate concentrations and microplastic contamination. 
  7. Inputs to biowaste treatment are often contaminated causing plastic and microplastic contamination of soils equal or superior to similar pollution to watercourses. Compost and digestate both transport plastic from inputs to soil.
  8. The value of biowaste treatment is in its GHG mitigation. This environmental service value is huge but is entirely unrecognised by policy makers to the extent that biowaste entering treatment does so at values often close to or below zero.
  9. The UK has a large biowaste treatment infrastructure capable of absorbing the extra 1-4 million tonnes of biowaste that will derive from obligatory biowaste collections post 2023. Yet the current financial situation of the industry signifies that most plant operators are running on negative equity with rapidly depreciating assets. Investments in new technologies and upgrading of existing plants will be compromised by the failure to attract investment funding.
  10. Government should look at using taxpayer money to incentivise high-quality feedstock collections recognising their GHG mitigation value through regulating gate fees, as well as valorising the return of organic carbon to soil, rather than simply incentivising energy production. Such incentives have distorted waste markets, created an industry totally dependent upon taxpayer grants to produce energy at a multiple of costs that other renewable sources and natural gas already provide and of which there is growing abundance.


3. Current and potential collection and treatment capacity 

For this document we will count as biowastes those according to the EU Waste Directive definition which Defra announced in a statement on 30 July 2020 will now be incorporated into UK law [4]:

‘bio-waste’ means biodegradable garden and park waste, food and kitchen waste from households, restaurants, caterers and retail premises and comparable waste from food processing plants [5]

The data relative to treatment capacity of biowaste now and in the future are not entirely clear but we will try to give some ideas to enable the narrative [6].

The British composting industry treats circa (c.) nine million tonnes of which around seven million tonnes is garden waste and has been one of the largest composting sectors in the EU for many years. There are c.250 open windrow plants across Britain for garden waste. This is a significant infrastructure and one of the largest in the EU.

British composters also treat around 1.9 million tonnes of other biowastes, such as food and farm waste; however, household food waste accounts for just 255,000 tonnes entering the 52 IVC plants across Britain. These are certified for the treatment of animal by-products, such as food waste but also industrial biogenic wastes, sewage and other sludges. This is also a significant number of plants and capacity.

Of the nine million tonnes being treated in composting household/business food waste currently represents just 0.3 per cent, whilst garden waste represents 77 per cent. 

The British AD industry is substantial and the third largest in the EU after Germany and Italy. More than 500 plants have a capacity to treat around 22 million tonnes of biogenic wastes with an estimated 80 per cent of capacity currently being deployed. That represents twice the size of UK composting overall, though one third is represented by farm AD treating either dedicated crops or farm wastes (manures). Of the remaining 14 million tonnes circa treated outside of farming, just 1.5 million tonnes can be classified as household or equivalent food waste, representing just 10 per cent of non-farm AD [7].

UK biowaste treatment capacity.
UK biowaste treatment capacity.

The average size of plants for AD is 40,000 tonnes per annum and for composting is 30,000 tonnes per annum, although for municipal solid waste (MSW) plants tend to be larger – nearer to 80,000 tonnes. With a European tendency to maximise efficiencies through large-scale plants (Milan 630,000 tonne per annum food waste; Denmark one million tonnes per annum animal slurries) the average size of UK plants is small. 

For our purposes in this document, total food waste (household and business) entering treatment in Britain in composting and AD in 2018 was approximately 1.8 million tonnes of which 1,500,000 in AD and 255,000 in IVC composting. Total garden waste entering composting was c. seven million tonnes.

Combined total treated UK garden waste (seven million tonnes) plus food waste from households/businesses similar to households (1.8mn tonnes) is currently 8.8 million tonnes. The organic waste sector in the UK is therefore by a large margin already the biggest waste recovery sector (the nearest is paper recovering around 5.5 million tonnes). Yet it seems to me that the relative weight of this industry is unrecognised by both policy makers and the waste sector as a whole.
Of total current household biowaste treatment overall (household food + garden waste) the composting sector dominates in terms of total volumes treated by a factor of 4:1 relative to AD.

It is not clear what is the potential amount that could be treated once the reforms Defra has announced are implemented mandating all English councils to separately collect biowaste from households and businesses by the end of 2023. If the reduction in food waste arisings continues – the Waste and Resources Action Programme (WRAP) reported a drop of seven per cent over the last three years – with an ambition to reduce this further by 50 per cent by 2030 under the Sustainable Development Goals (SDG 12.3), it becomes quite difficult to calculate what extra food waste arising there will be in England once collections are obligatory.

There are calculations that this could be as much as an extra three million tonnes of food waste from households and small businesses, plus another 1mn tonnes of garden waste. However, if we take into account falling volumes from reduction programmes and changed economic activity post Covid-19, these estimates could be too high. For the purposes of this document, we are not going to give an estimated extra volume coming into collection and treatment post 2023 because we are focusing upon the outputs, not the inputs. We will say somewhere between one and four million tonnes, referring to the Defra document already quoted for more detail [8].

4. What are the outputs from composting and anaerobic digestion?

There are two outputs, one is energy and the other is material to put to soil, compost and digestate. I will look at compost and digestate first.

Composting produces compost which is a soil improver. Output after moisture loss is about 30 per cent of inputs. Of nine million tonnes of all organic wastes composted currently, some three million tonnes of compost are available and with increased inputs that will grow. Were the outputs of 22 million tonnes of AD to be composted, this could add some one million tonnes of compost availability (five per cent dry matter). 

Compost contains about 30-50 per cent humidity with slow release nitrates and other nutrients but vitally, compost brings organic carbon to soil containing as it does c. 50 per cent organic carbon.  Compost can be spread to soil in most conditions as it is a soil-like material and will be absorbed and not run off in wet conditions. Compost is benign to plants, worms and microbes in soil, aids moisture retention and reduces the need for synthetic fertilizers. It can also be stored and bagged without harm to the environment (no emissions). The process of composting does result in some CO2 emissions <>above all from energy consumption calculated by Defra in their document to be some 1.4 million tonnes in 2018.

Organic carbon in soil can be renewed over long periods by restorative agricultural practices or through the application of soil improvers and organic material such as manure and compost. In the UK but also worldwide, organic carbon is steadily depleting and without organic carbon crops cannot be grown. 95 per cent of our food comes from soil and British farming in some areas already faces historically low organic carbon content. Organic carbon below 2.5 per cent is considered by some to be a limit of concern for crop reproduction and as the map shows, many areas have reached that limit. Michael Gove famously declared we have just 40 years of crops in our soils, partly due to falling organic carbon levels [10]. 

Compost can be put to soil freely as a commercial product if it reaches the standard PAS 100; if the material does not reach this standard, compost can be put to soil with a licence as waste. Around 170 [11] <>out of the total UK plants producing compost are certified to PAS 100 standard. Therefore, a considerable number are not certified (circa 130). This does not mean that all the uncertified compost is necessarily of a lower standard (e.g higher contaminant content) – it may be sold to local markets that do not require certification. However, we should be aware that this risk exists.

For the environmental value of digestate and compost in soils, a four-year study has been completed by the International Solid Waste Association (ISWA), which is recommended reading [12]. Locking organic carbon into soils through composting is also considered by the FAO and UNFCCC to contribute to reductions in GHG emissions [13]. <>Compost can substitute fossil fuel origin fertilisers and therefore further contribute to reductions in GHG emissions.

AD outputs known as digestate bring greater concentrations of nutrients in wet digestate equivalent to 95 per cent of inputs, mostly liquid with a little fibre (c. five per cent). This can be spread to land only in specific drier weather conditions and needs storage in lagoons until spreading is possible. This may have the effect of producing atmospheric ammonia emissions. Defra considers that four per cent of ammonia emissions nationally derive from AD digestate storage lagoons [14]. <>Biogas production also causes methane emissions due to leakages that (in well run plants) will be less than one per cent but in smaller, less professionally managed plants may be much higher. Defra calculates AD CO2 emissions to be around 160,000 tonnes in 2018.

Nitrate is a fertiliser and digestate can substitute the need for nitrates used from fossil fuel sources, such as urea. As such, use of digestate can contribute to reducing GHG emissions from fertiliser production. Digestate can be put to soil freely if it reaches the PAS 110 standard. Approximately 90 suppliers of digestate are registered as certified to PAS 110 under the Biofertilisers Certification Scheme out of c. 500 UK AD plants [15]. This does not mean that other digestates are necessarily of an inferior quality to those certified, but many will be (contaminant levels for example). 

Digestate brings virtually no benefit of organic carbon restoration to soil and can be harmful to microbes/worms in soil [16].  The GHG contribution of digestate is in the substitution of fossil fuel based fertilisers and according to a World Biogas Association (WBA) report from 2019 digestate has the potential to substitute seven per cent of fossil fuel produced nitrogen globally, a significant amount [17].

However, in common with many European nations, the UK has an abundant supply of free or negative-cost nitrates to soil from various sources such as on-farm AD, manures, sewage sludges, other animal slurries such as poultry. Further, 55 per cent of British territory is classified as a nitrate vulnerable zone [18], ones in which an excess of nitrates are present in soils or ones in which run-off of nitrates from soils into water courses is high risk, causing eutrophication of these. This severely restricts both the territory and the time periods digestate can be spread to soil (more so than compost as it is a dry material) and therefore its market value is usually negative – even though the nitrogen content intrinsically holds value to farmers.

Farmers have their own landbank to which to apply digestate. It is not an issue to them that the value of the digestate is negative, it is their own. The negative value of digestate becomes an issue when AD producers seek a landbank to which to apply it. This is the case of two thirds of the AD production in Britain and this issue will grow with growing volumes of biowaste entering AD post 2023.

Whilst there are some examples of operators obtaining income from the sale of compost and digestate these are rare, and often the income is less than the cost of transporting and distributing the materials to farms/users. Essentially, almost all physical outputs have zero value. In terms of market demand and value, we therefore have to ask ourselves for what purpose are compost and digestate currently being produced?

Now we look at the energy output.

AD’s unique selling point is that it also produces energy in the form of biogas used either as upgraded biomethane in vehicle fuel or into the national gas grid where it is the qualitative equivalent of natural gas; or burnt to generate electricity. These uses have value due to the market sales price of the fuels themselves as well as the additional price incentive received through schemes like the Renewable Heat Incentive (RHI) or Renewable Transport Fuel Obligation (RTFO) to promote renewable energy/fuel sources. Were biogas to compete on the marketplace for the sale of electricity and gas, it would be unable to. Electricity is generated at £0.4c/kWh from offshore wind; natural gas is available almost for free (£0.5c/kWh) in certain market conditions and is abundant globally and locally.

Whilst biogas is classified as a renewable energy, its combustion in a vehicle engine or in domestic heating still emits the same amount of CO2 as natural gas. The molecules are identical.

The Committee on Climate Change (CCC) [19] suggests caution in the use of biomethane as a climate change abatement tool for transport. The renewable classification therefore should not be used as we freely do with respect to its overall performance as its emissions are identical to natural gas,  but we should define biogas as renewable only because its feedstock substitutes fossil fuels with waste/renewable feedstocks. Of course, this is a significant advantage in terms of avoided emissions from wastes that would otherwise emit methane from uncontrolled decomposition. 

5. Gate Fees, incentives and finances

It is one of the paradoxes of waste management (and not just in the UK) that 50 per cent of English councils prefer to send biowaste to landfill or incineration rather than AD or composting, despite the enormous difference in gate fees between them.

Waste treatment gate fees.
Waste treatment gate fees.

The costs of separate collection of biowaste are clearly responsible in part for councils taking this decision, but is it all?
The strenuous lobbying undertaken against the separate collection of biowaste by ESA and major waste companies is indicative of where they see their financial interests. If such lobbying continues, I believe that councils will continue to apply TEEP criteria to as much biowaste collection as possible, ensuring its continual disposal in incineration. This view is influencing the way councils think about managing their biowastes.

Government contributes to the paradox by allowing incineration to claim renewable energy incentives on the biomass part they burn, exactly that fraction that should be destined to composting and AD. The UK continues to build and plans to build many more incinerators presumably because major waste operators believe in the future that among wastes needing disposal will be a considerable amount of biowaste. Let’s not forget, five million tonnes a year is still destined to landfill now. That major waste operators actually manage very small amounts of biowaste through AD or composting is indicative of how they view the future of that industry.

Yet we have seen that as a nation we do not need expensive electricity or even heat produced by waste. We have cheap electricity produced by wind, solar, hydropower and even natural gas with the same GHG outputs upon burning as biogas. What we need is organic carbon for our soils and we should consider the biogas/biomethane outputs from this process almost as a beneficial by-product.

I would therefore argue that we need to rethink the way in which incentives and gate fees are modulated before we embark upon major reforms to our waste management industry. Getting the economics right is key to getting the right collection and treatment infrastructure in place.

Average gate fees are reported by WRAP [20] as in the table above. For AD they can be as low as zero (or even negative with examples of operators buying feedstocks) or as high as £50/tonne. Composters rely on gate fees, which vary from £15-50/tonne with an average of £30. They receive no incentives for the organic carbon locked back into soil through spreading of compost despite the climate change benefits and agricultural production security these bring nor for the substitution of fossil fuels used to produce fertilisers. Given profit margins of operators, we can assume the cost of In-Vessel Composting treatment of food waste is circa £30-40/tonne and open windrow £15-20/tonne, depending upon the quality of inputs and the scale of operations. 

AD operators treating food waste (remember, we are focusing on the domestic and business equivalents of food waste here), receive almost all of their income from sales of energy and from energy incentives. From the accounts of one AD operator we can value these as the equivalent to a <>£67/tonne gate fee. We can conclude from this that (considering profit margins) the cost of treating a tonne of biowaste in AD is currently circa £55-60/tonne. We shall see more on this below.

The figures relating to estimated UK treatment costs (£30-40/tonne IVC and £55-60/tonne AD) are consistent with EU gate fees for biowaste. 

I argue that the value of the UK biowaste treatment industry currently is therefore to be found in:

  1. The reduced volumes of waste needing disposal with the associated savings of GHG emissions (methane from landfills, CO2 from incineration). These are important values – several percentage points of UK GHG emissions have been and will be saved by taking biowaste from disposal to treatment and therefore the investments in this sector, as a waste treatment and GHG reduction instrument, are critical and strategic to achieving net zero by 2050. 
  2. The sales value of biogas at market prices without incentives.

However, there are potential values which the economics of current waste policies do not recognise in the outputs of both AD and compost:

  1. The value of nutrients and organic carbon put to soil to substitute fossil fuel fertilisers.
  2. The value of organic carbon stored in soil as a GHG abatement tool.
  3. The enhanced value to farming through long term increases in organic carbon.
  4. The enhanced Natural Capital achieved by improved soil quality.

Whilst we are giving taxpayer subsidies to both burning and digesting biowaste because of the energy outputs we have privileged in the past, now is the moment we have to think about moving those subsidies to privileging the organic carbon we could produce and need for our soils and farming.

There is no subsidy or taxpayer recognition of the activity of composting. The activity is itself paid for by those that confer waste; whilst the outputs sent to soil enjoy no subsidy recognition for the compost placed to soil and are given away at negative value. The organic carbon, the Natural Capital value, is not recognised. 

Both composting and AD are GHG avoidance technologies but only one is incentivised. I repeat that as a nation we do not need, nor is there a shortage of the gas or the renewable electricity produced by AD whilst burning biogas contributes to CO2 emissions exactly as natural gas does. Such emissions are currently inevitable as we transition away from coal and oil and as wind and solar power grow.

However, there is also a serious shortage of organic carbon in soils and this is totally unrecognised by fiscal mechanisms.
This policy has created an unlevel playing field causing competition between the two sectors, by privileging the outputs of one over the other whilst failing to recognise that both have the same valuable benefits of avoiding emissions from the disposal of biogenic wastes. We therefore have to rebalance the incentives given to the treatment of biogenic wastes and recognise

  1. The equal value in composting and AD of the avoided emissions from waste disposal.
  2. That mixed biowaste (food and garden) may be collected together for composting.
  3. The value of organic carbon deposited to soil as a carbon storage in providing incentives to farmers.
  4. That gate fees should cover the profitable operating costs of the treatment plants because the value of these is not in outputs but in reducing GHG emissions through waste treatment.
  5. That we should eliminate incentives to the sale of gas and electricity leaving pricing to market mechanisms (saving on-farm production as a means to supplement farm incomes). It is unjustifiable for the UK taxpayer to subsidise the production of energy that has no economic or GHG advantage over what it can substitute.
  6. That incentives should be used only when industry is forced by legislation to implement technological change e.g. such as converting biogas to hydrogen. 

Another current paradox is that the overall economic value of both industries is small considering the volumes of waste they treat. If we assume that £67/tonne is an average income for AD the turnover of the British AD biowaste industry (which we estimate to be 1.5 million tonnes as above), incentives and energy sales included, is c. £100 million. The value of the British composting industry (7.3 million tonnes of food and garden wastes) is circa £200 million. Considering both industries combined treat c. nine million tonnes of various waste biowastes as defined above, recycling more than any other sector, this is a tiny proportion of the overall turnover of the UK waste industry, estimated by Defra to be £7 billion in 2018 [21].
Clearly, the biowaste industry is heavily undervalued in the UK and at the heart of this is a distorted incentive regime. As a result the biowaste treatment industry does not punch with the weight its industrial reality represents.

I learnt from AD and composting operators while drawing up this document and I confess was surprised by some of the data I received. I recall from my  experience that there was little  value in AD and we sent food waste to composting; we even sent the digestate from one small AD plant to incineration, because this was a cheaper option than paying farmers to take a material they didn’t want or need.  But I was surprised that now, in 2020, the situation has in some senses worsened.

Both AD and composting plants gave me data to show they are operating profitably, some with small margins, others with higher margins especially when treating commercial waste. What was shocking to me, however, is that the depreciation costs of plants were rarely accounted for; in other words, industrial assets that naturally depreciate due to wear and tear (treating biowaste produces aggressive corrosion) do not factor in that their asset value declines year by year. In fact, return on invested capital in both AD and composting appears in many cases to be close to zero. I have plant data to show this that I cannot share because it is confidential.

If such data were to be common across Britain, this would lead me to believe that current AD and composting plant assets are 1) hard to sell should owners wish to liquidate their investments and 2) hard to finance should expansion or technological upscaling be needed. This traps the plants in a situation where they will sweat the assets until exhaustion and will avoid having to invest in improvements (for example, were they imposed by regulators).  

Of course this statement is not true for all operators – where large-scale and multi-plant operators have entered the market and consolidated operations and have access to finance through aggregation or size (for example, on the back of waste water treatment) the finances have a different look. 

The other point I noted from some AD operators specifically is that gate fees constitute a minimal part of income while the cost of “exporting” digestate and extracting packaging contaminants to send to disposal can together constitute as much as one third of all income. I find this unsustainable, because it signifies that plant operators are totally dependent upon the renewable energy incentives they receive for the biogas. In other words, these are not operations driven by market conditions; without incentives or a remodulation of gate fees to recognise the environmental services they provide, they would close. 

6. Suggested ways forward

For climate change reasons alone, Britain has to treat its biowastes. This does not include burning them.

When we consider biowaste treatment, we forget there are also gains to be made in improving the quality of other wastes which become cleaner when wet food is not mixed with them (plastics, paper, aluminium, glass) and therefore potentially hold higher value. This is never recognised when evaluating food waste collections.

Further, the gains in soil fertility through the correct application of nutrients and the deposit of clean organic carbon, are rarely calculated in assessments of food waste collection. No GHG benefit is ever calculated for the sequestration of organic carbon in soil. The ISWA study cited looks at these in detail and indicates how to measure and unlock these potential values.  As a minimum calculation, a tonne of clean compost is worth c. £20 in agronomic terms plus GHG abatement value. 

As treating food waste is not just a legal but also a climate obligation, we need to support the treatment infrastructure to ensure capacity is available and the correct returns are created, economically, environmentally and socially. It is difficult to understand how we can continue to approve applications to build incinerators, to which food waste is delivered at £110+/tonne and destroyed with zero environmental returns, but cannot stimulate food waste collections and treatment even though the cost of food waste treatment is half as much and the environmental returns are known to science.

At the same time, by privileging AD with incentives on the mistaken assumption we need the biogas and electricity produced, we have put the larger, cheaper and more readily available compost industry at a competitive disadvantage. Yet, if we are to treat 1-4 million more tonnes of biowaste (food 1-3 million tonnes, garden waste 0-1 million tonnes) post 2023, the extra cost we need to give as incentives to AD to pay the treatment cost/profit of £67/tonne, are far higher than were we to send those tonnages to composting. 

The annual extra cost to UK PLC and taxpayers to incentivise AD to treat three million tonnes of food waste are in the region of an extra £200 million/year. Conversely, were we to send those three million tonnes to composting, that has lower unit costs of treatment, the cost would be an extra £120 million/year. The benefit we would obtain in terms of organic carbon for soils which we have a shortage of, should be compared in value to the benefit we get in biogas, for which we have abundant volumes of its equivalent, natural gas, at near to zero values. 

We therefore need to rebalance this whole system before it is too late, before we commit to another chunk of unsustainable incentives to produce energy we do not need and fail to obtain organic carbon we do need. 

Looking around Europe we can see many examples of higher value systems and they have in common several features which I raise here in a series of questions and suggestions to policy makers:

  1. Apply and enforce minimum food waste collection and recycling targets with the councils/counties/authorities having the charge of realising them. England proposes implementing food waste collections, but with what targets? Zero food waste to landfill by 2030 may mean lots of food waste to incineration. Is 15 kilogrammes/capita intercepted by collection systems considered acceptable when 45-50 kilogrammes/capita would continue to go to disposal? What is the benchmark and what are the penalties put into place for non-compliance? At present I do not understand whether Defra has made these assessments.
  2. A way of approaching a benchmarking is to make a  target for reducing food waste in residual waste, e.g if food waste available is 100, then no more than 15 should be collected with residual. This can easily be measured. This is the level Milan has reached for example [22].
  3. Many countries are applying an incineration tax to disincentivise destruction of waste over recovery. Denmark, once paladin of incineration, has now understood it has over-relied upon incineration to the detriment of material recovery [23] and needs to import waste to keep its plants running. Britain risks making the same mistake.
  4. We forget that we give RHI incentives to incineration on burning the biogenic fraction as a renewable energy known as ‘Solid biomass contained in waste’, i.e. on precisely the fraction of waste which we should be valorising in composting and AD and avoiding those CO2 emissions. We should stop this immediately.
  5. Mandate the same outputs for composting and AD to create a level playing field between the two and to forge cooperation – in almost all of Europe, food waste digestate (not farm waste as farmers have their own landbank) must be dewatered and composted and in Britain organic carbon, not liquid nitrates, are needed. Further, this would drive the move towards dry AD technologies in which both garden and wet food waste can be treated in the same plants. As we will have more waste to treat post 2023, this is a perfect time to drive this technological change and create the conditions for those investments now.
  6. Ban the deposit to soil of non-PAS 100/110 compliant materials whilst raising the standards on both to reduce contamination as the Scottish have done. Non-compliant materials must go to either landfill cover (with a reduced landfill tax) or to incineration. This will force up the standards of inputs, process and outputs. It is unacceptable that we should be legally applying to soil materials, which are potential pollutants in the name of the circular economy or waste recovery. If the outputs of food waste treatment do not bring net benefits to soil, we should indeed be incinerating food waste. 
  7. Establish minimum gate fees based upon quality of collection inputs upon the Catalonia model; plants must be able to survive financially and profit from their principle activity, treating waste. This is their core value, as waste processors reducing GHG emissions by treating biogenic wastes. Let’s be frank, their outputs are currently of little value and do not merit taxpayer subsidies when we can produce renewable electricity or have natural gas available much more cheaply and when farmers are not prepared to pay a penny for compost or digestate. 
  8. Privilege the recovery of organic carbon stock in soils where organic carbon is at a dangerously low level- aim to rebuild OC in those soils beyond three per cent and pay farmers to use certified, clean compost or manures as an instrument for doing so. Incentives under the EU Rural Development programme in the 2000s of €300/hectare were initiated in several EU regions leading to significant take up of compost and thereby creating a market for this material beyond that created by this incentive itself.  This is where stimulus money should be spent, not on incinerating food waste.
  9. Incentives should only be given to production of outputs when Government decides to push new technologies which require new investments over and above daily BAU (e.g. from biogas to biomethane or to hydrogen). Current indicators are that gate fees in Western Europe for food waste are a minimum of £60/tonne and the UK should apply minimum gates fees here too, decreasing incentives by the same amount to create level playing fields for inputs through a national gate fee regime. Such gate fees would represent a 50 per cent saving for councils sending their food waste to treatment compared to current incineration gates fees (£110+/tonne) or 40 per cent when compared to landfill gate fees (£100/tonne). These savings must be set against the extra costs that councils initially have in investing in new waste collections of food waste. Let’s not forget, councils can also raise council taxes to finance new services. 

With these policies among others, Britain can develop a first class, food waste treatment system providing thousands of jobs as well as beneficial outcomes.

Currently as the system is organised, this is not going to happen and we will waste taxpayers money on subsidising the production of energy we do not need, digestate we do not need and poor quality composts that have zero value. Now is the time for a reassessment and to get the system future proofed. 

I hope this paper sparks a debate around these issues. 



[2] Ibid





[7] Source:  NNFCC