House of Commons - Waste management in England - Environment, Food and Rural Affairs Committee

Waste management in England - Environment, Food and Rural Affairs Committee Contents

4 Residual waste treatment

Exporting waste for energy recovery

56. Importing and exporting waste for recovery is generally permitted, depending on country controls, waste type and destination. Refuse derived fuel (RDF) is low grade fuel processed specifically for consumption in energy-from-waste facilities. There has been a marked increase in exports of RDF from England to Europe since 2010 (when there was virtually nil).[79] In 2013, England and Wales exported a total volume of 1,157,895 tonnes of RDF, primarily to the Netherlands (69.6%) and Germany (12%).[80]

57. This relatively new practice seems to have sprung up in reaction to a lack of available energy-from-waste infrastructure in England. David Palmer-Jones, CEO of SITA UK, explained that the export of RDF is:

58. CIWM share this view about availability of infrastructure capacity and explain that:

59. Many witnesses called for more infrastructure capacity to treat waste in England. Different technologies are needed to treat different types of waste, but all share the common trait of needing a significant amount of investment and relatively long lead-in times. The National Association of Waste Disposal Officers warned that "without an overview of the number and location of the various processing options, the risk of creating over-capacity in some methodologies, which would in turn threaten the viability of others, will be a risk".[83] Dr Liz Goodwin at WRAP looked to Defra to play a role in ensuring that the right amount of the right type infrastructure is available:

60. We recommend that Defra analyses data on waste flows and waste flow forecasts in order to provide the waste sector with clear guidance on how much energy-from-waste infrastructure capacity is needed in England to gain an optimal balance between export and local treatment.

61. Some witnesses were also concerned that the practice of exporting RDF does not adhere to the principles of the waste hierarchy and can have adverse impacts on the economy due to the loss of resources and loss of potential investment in infrastructure, employment and associated community benefits in England.[85] The export of RDF also impacts on energy security and Defra acknowledges additional concerns around minimally treated RDF which contains significant quantities of recyclable materials being produced for export.[86]

62. In response to the various concerns surrounding the practice of exporting RDF, Defra issued a call for evidence in March 2014 to determine whether there is a case for Government action to ensure that export of RDF is the best treatment option in terms of the environment. Defra is still analysing the feedback.[87]

63. We commend Defra for issuing a call for evidence on the practice of exporting RDF and we look forward to Defra's response in due course.

64. We recommend that, in its response to this Report, Defra include an assessment of the economic impact of building the infrastructure needed to treat the RDF currently exported compared with the economic impact of the current practice of exporting RDF from England to other countries in Europe.

Anaerobic digestion

65. In the anaerobic digestion (AD) process, food waste and other wet biowaste (e.g. manures, slurries and sludges) is broken down by micro-organisms in enclosed containers in the near absence of oxygen. Defra has scientific evidence, based on life-cycle analysis, which shows that anaerobic digestion is environmentally better than composting and other recovery options for food.[88] This is an example of an acceptable departure from the waste hierarchy where a clearly better environmental outcome can be shown.

66. Defra worked with industry to develop the Anaerobic Digestion Strategy and Action Plan 2011, with an aim of overcoming the barriers to the deployment of AD. There are currently 145 operational AD plants in the UK with an installed electrical capacity over 150MW. Of these 145 plants, 44% treat agricultural waste such as farm manures and slurries, 38% treat food waste from municipal and commercial sources, while the remaining 18% process industrial waste such as brewery effluent.[89] The Anaerobic Digestion and Biogas Association notes that there is still significant potential for the AD industry to expand as only 7% of all waste is currently processed through AD.[90]

67. Evidence we received predominantly praised the effectiveness of Defra's Anaerobic Digestion Strategy and Action Plan 2011 and welcomed the clear central Government commitment it demonstrated, although some witnesses pointed to DECC's renewable energy incentives as much more of a driver towards building new AD plants.[91]

68. Despite its growing deployment, AD operators still face a number of challenges, including access to regular and appropriate waste feedstock over the life of the AD plant. Some witnesses, including Dr Goodwin at WRAP, endorsed separate food waste collections, to get the food out of landfill and to use it to generate energy and biogas through the anaerobic digestion process.[92] Currently about four million tonnes of food waste still gets sent to landfill but, as discussed in paragraph 32 above, separate food collection services for domestic households have varying levels of success and can be disproportionately costly. We also received evidence that it is very difficult to separate food waste out at the right quality, quantity and in the right place to feed an AD plant.[93] Mechline Developments Ltd were particularly concerned about separate food waste collections for onward use as AD feedstock and identified a range of associated risks, including contamination levels; carbon emissions from the consequential higher road traffic; and reducing the incentive to minimise food waste and redistribute edible food.[94]

69. In certain circumstances, purpose-grown crops or biomass such as maize, grass silage or whole-crop cereals are used as a feedstock for anaerobic digesters. Defra's Anaerobic Digestion Strategy and Action Plan 2011 explains that:

70. We agree with Defra that the greatest benefit of anaerobic digestion is in dealing with waste feedstock, not purpose-grown crops. However, sourcing appropriate waste feedstock on a consistent basis remains a significant challenge for AD operators and more work is needed to address the issues surrounding separate food waste collections.

71. The Government must find ways of diverting more food waste out of the residual waste stream by methods which are economically and environmentally viable and suitable to local circumstances. Where food waste is separately collected it should be treated at local AD plants whenever possible to address the problem of sourcing waste feedstock.

72. Anaerobic digestion produces biogas and digestate. Biogas can be used to generate renewable heat and power, which helps to reduce the use of fossil fuel and reduce greenhouse gas emissions. Digestate is rich in nutrients, so it is a valuable bio-fertiliser which can be used instead of fossil fuel-intensive fertilisers. The nutrient composition of the digestate depends on the feedstock but must comply with the PAS 110 standard to meet with national requirements in Britain. Meeting this standard requires source segregation of food waste. However, CIWM highlighted that despite the requirements, the markets for digestate were not always secure as demand was seasonal and the nutrients in digestate were needed in different ratios and quantities in different soils. This can be compounded by a lack of confidence by some important agricultural customers in the digestate, due to the lack of information available about its long-term effects.[96] As further explained by Defra:

73. In order to improve the confidence of agricultural customers and improve the stability of the market for digestate, we recommend that further research is undertaken to determine the long-term effects of AD digestate on the quality and composition of soil and crops.

Incineration with energy recovery

74. Incineration with energy recovery is generally placed higher up the waste hierarchy than landfill in terms of environmental performance and is considered by Defra to be the best waste management option for most genuinely residual waste.[98] It is a waste treatment process where organic substances contained in waste materials are burnt and converted into ash, flue gas and heat. The incineration bottom ash goes to landfill or can be reused as construction aggregate material; the flue gases must be cleaned of gaseous and particulate pollutants before being dispersed into the atmosphere; and the heat can be used as heat and/or to generate power.

75. Incinerators with energy recovery are typically cited to have electric efficiencies of up to approximately 27%[99] but can be much more efficient if the heat energy is used for local district heating or nearby industrial processes. Steve Lee, CEO of CIWM, referred to the inclusion of heat recovery as the "secret difference between being 25% or 26% efficient and 75% to 80% efficient".[100] However, in most instances, electricity alone is recovered from incineration as it can be easily distributed and sold via the national grid. Dr Colin Church, Director of Resource, Atmosphere and Sustainability at Defra told us that there are currently 42 incinerator plants in England and all those that Defra supports have the capacity to use heat; but only a very small number—"a handful"—use it.[101]

76. The Government should encourage the use of heat outputs from incinerators for local district heating for buildings and/or for industrial processes to gain maximum efficiencies from incineration processes. Defra should explore the barriers to using heat recovery and collaborate with DECC and DCLG to ensure that Government policies, planning permissions, permits and incentives are all aligned to enable higher efficiencies for incineration plants.

77. The use of incinerators for waste treatment can be controversial due to worries over health and environmental risk from the pollutants that can be released into the atmosphere (most significantly, dioxin and furans) and concerns that availability of incinerator capacity could have a negative impact on recycling rates. UKWIN told us that recycling is harmed by incineration for various reasons, including the presence of incineration capacity and government subsidies for incineration discouraging investment in recycling, the long-term lock-in of money and feedstock to existing and proposed incineration capacity, and the fact that the true costs of incineration are not reflected in the price of treatment.[102] UKWIN also provided us with data showing an apparent correlation between high rates of incineration and low rates of recycling.[103]

78. In response to the concerns about harmful emissions and environmental impact, witnesses including ESA and CIWM assured us that this is one of the most tightly regulated industrial process in Europe.[104] Public Health England's position is that modern, well-managed incinerators make only a small contribution to local concentrations of air pollutants and that the risks to human health from these plants are likely to be very small and not detectable.[105]

79. Concerns about the possible negative impact on recycling rates tend to focus on the typically long-term contracts entered into by local authorities for the supply of waste feedstock to the incinerator. Once the incinerator infrastructure exists it needs to be fed with waste so local authorities commonly agree to supply a minimum or fixed tonnage of waste to the incinerator (or pay a fine). This is referred to as "put or pay". The commercial risk of higher recycling rates and changing waste legislation or policy (i.e. banning incineration of food waste) is therefore also taken by the local authority. Some witnesses, such as Zero Waste England and UKWIN, argued that "put or pay" leads to a perverse incentive for local authorities to withdraw recycling schemes to ensure that they can comply with their contractual obligations for waste supply to incinerators. Similarly, Oxfordshire County Council told us that they have no minimum tonnage contracted with the energy-from-waste facility they use which enables the council to reduce and recycle as much waste as possible. Consequently, its recycling rates are around 60%.[106]

80. Conversely, the Resource Association believe that:

107

This view is reinforced by evidence showing that the four top performing EU countries with over 50% recycling rates also operate some of the highest levels of energy-from-waste capacity.[108]

81. When we asked the Minister how the Government ensures that only genuinely residual waste is sent to incinerators, he told us that the key pressure is gate fees—i.e. the charge that must be paid to dispose of waste in an incineration facility. However, we are concerned about the effectiveness of this singular mechanism following evidence we received about "put or pay" contracts and negative impacts on recycling rates.

82. In most cases, the environmental benefits of recycling household waste are higher than sending it to energy-from-waste technologies such as incineration. However, we do not think that high levels of recycling are incompatible with the use of incineration for genuinely residual waste.

83. We urge Defra to ensure that waste sent to energy-from-waste plants such as incinerators is only genuinely residual waste. We ask Defra to assess whether the use of gate fees is sufficient to achieve this aim and to confirm whether additional interventions, such as regulatory requirements to remove dry recyclables or higher gate fees have been fully considered.

Waste fires

84. During 2012 and 2013, 595 incidents of fire were reported at privately operated waste management sites. This represents an average of one fire for every 18 such sites.[109] Waste fires can burn for days and have significant impacts, including:

polluting the environment;
harm, cost and inconvenience caused to local communities;
public health issues;
firefighter safety; and
straining the resources of local authorities, the fire service and the Environment Agency.

In addition, it is often valuable recyclates which burn causing significant financial loss to the owner of the site.

85. The Environment Agency regulates waste management facilities, including monitoring and enforcement issues, and licensing and monitoring transport of waste. The operator of a waste management site holds a permit issued by the Environment Agency, setting out the measures that must be taken to minimise pollution and harm to health, including carrying out risk assessments and putting in place an accident plan to reduce fire risk. In response to the numerous occurrences of waste fires, the Environment Agency issued fire safety guidance for waste and recycling site operators in October 2013.[110] The guidance addresses fire prevention as the key for operators of waste sites. It recommends keeping sources of ignition at least six metres away from stacks of combustible material and introducing a regular maintenance and inspection programme. Storage times is another area identified as a risk. The guidance sets a six-month limit on how long RDF and smaller fractions of waste (known as 'fines') can be stockpiled.

86. More recently, the Chief Fire Officers' Association addressed the All-Party Parliamentary Group for Fire Safety and Guidance to inform members of both Houses of the collaborative work being undertaken with the Environment Agency and the waste sector to develop a fire code of practice; to share data and information; and to revise national operational guidance on fighting fires.

87. The Minister acknowledged that there are issues around the resources of fire and rescue services, as well as the fact that some operators are not complying with the conditions of their permits. He also confirmed that Defra has secured an extra £5 million to deal with waste crime (including waste fires) and was working with the Environment Agency to work out how to make the best use of that money.[111] In order to tackle the problem of waste fires, he explained that "it is important that we get tough on the operators that are not living up to their permits".[112]

88. We commend the work of the Environment Agency assisting operators with the problem of waste fires and we support the work being undertaken by the Chief Fire Officers' Association in relation to this serious issue.

89. We expect Defra and DCLG to take action to address the frequent occurrence of fires at waste management sites and to support the development of the fire code of practice by the Chief Fire Officers' Association. Defra must ensure that additional resources are deployed in the best way possible to monitor and enforce the conditions of the requisite permits.

79 Defra [WME 0072] para 4.7 Back

80 SITA UK [WME 0075] para 6 and 7 Back

81 Q75 Back

82 Chartered Institution of Wastes Management [WME 0073] para 52 Back

83 National Association of Waste Disposal Officers [WME 0011] para 5.1.1 Back

84 Q308 Back

85 See Q76 [Dan Cooke] Back

86 Defra [WME 0072] para 4.7 Back

87 Defra, Refuse-derived fuel market in England: call for evidence, 12 March 2014 Back

88 Defra [WME 0072] para 1.5 Back

89 Anaerobic Digestion and Biogas Association [WME 0060] para 5 Back

90 Ibid., para 6 Back