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Chartered Institution of Water and
Environmental Management (CIWEM)

106-109 Saffron Hill, London, EC1N 8QS  
Tel: 020 7831 3110 Fax: 020 7405 4967
 

Energy Recovery from Waste

Purpose

This Policy Position Statement (PPS) considers the issues surrounding the potential for expansion of energy from waste as a waste management solution and sets out the position of the Chartered Institution of Water and Environmental Management on how best to progress this sensitive issue.

 

CIWEM's Position on Energy from Waste:

  1. CIWEM considers that energy recovery from waste has a legitimate role to play in the portfolio of sustainable waste management measures.
  2. CIWEM supports wider use of combined heat and power (CHP), which represents the most efficient method of energy recovery from waste and encourages consideration of the role that it could play in reducing our reliance on conventional fossil fuels.
  3. CIWEM considers that the Government should assess the current and likely future market for waste derived fuels that are still classified as waste - especially in high energy use industries where security and diversity of fuel supply could deliver a commercial advantage.
  4. CIWEM urges the Government to support Europe-wide standard setting for waste derived fuels.
  5. In the upcoming European  negotiations on the Waste Framework Directive, CIWEM considers that there would be benefit in pressing for the de-classification  as "waste" those refuse-derived fuels (RDFs) which are of sufficiently high quality.  The Institution also considers that there is a need for greater research and development on RDFs in order to increase the proportion which may be co-fired without any reduction in emissions standards and we urge the Government to support this.
  6. If EfW is to deliver real benefit to the UK then more should be done at a strategic and planning level to encourage the uptake of CHP which improves the efficiency of energy recovery considerably.
  7. CIWEM considers that Energy from Waste (EfW) has a significant role to play in meeting the Landfill Directive targets for the diversion of biodegradable municipal waste from landfill.
  8. CIWEM considers that the public perception of energy from waste is clouded by past performance and that stringent emissions standards which must now be adhered to are such that EfW should provide no greater air pollution than many common and widely accepted sources.

 

Context

Energy Recovery from Waste describes the process in which energy (in the form of heat) is recovered from the incineration of waste, and used to generate electricity which is then fed back into the national grid, or provide both electricity and heat (combined heat and power) to nearby communities or other uses.  Waste may be in the form of an individual waste stream, generally from a commercial or industrial activity, which is used in existing plant as a fuel; it may be the residue once recyclables are separated from a general waste stream; or it may be a specially produced refuse-derived fuel (RDF) which must meet certain standards to be burnt in certain plant such as cement kilns or, potentially, power station furnaces.

There is a range of incinerator technology used, from mass-burn (generally the simplest approach) to fluidised bed combustion (utilising a moving bed of sand), pyrolysis and gasification (more novel technologies which produce gas from the waste by heating it in either a zero or low-oxygen environment, which is then burnt).  Anaerobic digestion of waste is not covered in this PPS.

There are currently about 15 energy from waste (EfW) plants in the UK, which together incinerate over 3 million tonnes of municipal waste.  To put this into context, in 2004/5, 67% of municipal waste was sent to landfill, 23.5% recycled or composted and 9% incinerated1.  Recently, waste incineration in the UK has been unpopular with the public, with fears over the health effects of emissions from EfW plants.  Some of these fears are fuelled by the poor emissions performance of the previous generation of incinerators. Yet stringent restrictions imposed by the EC on the amount of waste which maybe be sent to landfill has led to the Government indicating in its Waste Strategy Review that EfW may have to play a bigger role, despite the current emphasis on recycling.  The Government estimates that EfW could increase from its current 9% of MSW treated to around 25% if waste growth levels are high.

Expansion of EfW has also been set against the need to deliver reductions in the amount of greenhouse gas emissions.  Waste has the potential to replace a small amount of conventional fossil fuels which are burnt to generate electricity, and consequently power generated in EfW plants has been exempted from the Climate Change Levy.  There are also calls for a wider range of wastes to be permitted to be co-fired in industrial kilns and boilers and for EfW to be classified as a renewable source of energy.  Increasing concerns about future security of energy supplies have also led to calls from some quarters for expansion of EfW as a secure source of energy for the UK.

 

Key Issues

EfW as a Sustainable Waste Management Tool

As a result of the EU Landfill Directive, improved rates of recycling by local authorities are being seen and targets exist to recycle or compost at least 33% of household waste by 2015.  It may be reasonable to expect even better rates of recycling with time.  Despite this, municipal waste (MSW) production is growing by approximately 2% per annum and there are targets under the Landfill Directive to reduce the amount of waste sent to landfill considerably.  Even if Landfill Directive targets are met, half of all biodegradable municipal waste (BMW) could still be sent to landfill in 2013 and over a third in 2020.

There remains a significant gap between the amount of waste which will be able to be sent to landfill, and that which may be recycled.  Elsewhere in Europe EfW is widely used as the mainstay of waste management strategies and though Defra has stated that EfW in the UK is unlikely to match the amounts combusted in Europe it could feasibly deal with up to 27% of MSW by 2020.

Public Opposition and Concern / Perception - Pollution
Public perception of waste incinerators / EfW plant in the UK is far from positive and there is generally significant opposition to proposals for their construction.  This stems from fears over the heath and environmental impacts of the pollutants emitted and is manifested in a typical 'not in my back yard' reaction.    The primary pollutants of concern are dioxins, heavy metals, acid gases, nitrogen oxides and particulates.  The presence of dioxins in particular has resulted in fear and opposition because of their carcinogenic properties and persistence in the food chain.  Other pollutants can cause respiratory illness in susceptible individuals.

Waste incineration is highly regulated at a number of levels.  The Environment Agency regulates releases to the environment in England and Wales (as does SEPA in Scotland and DOENI in Northern Ireland).  The EU Waste Incineration Directive 2000 introduced tight emissions standards for waste incinerators. The Directive aims to minimise the impact of negative effects on the environment and human health resulting from emissions to air, soil, surface and ground water from the incineration and co-incineration of waste, and is implemented largely via the existing permitting requirements of the Pollution Prevention and Control (England and Wales) Regulations 2000.  Consequently, levels of dioxins and other pollutants from incinerators are now amongst the lowest when compared to other common air pollution sources such as house or forest fires, or fireworks.  This is supported by Defra commissioned research on environmental and health effects of waste management which has concluded that health risks posed by incineration of waste are small in comparison with other known risks faced by most people in their daily lives.

Energy

The Government's recent Energy Review has emphasized concerns over the future security and diversity of the energy resources which are used to generate power.  EfW plants could play a limited, but increased role in generating electricity and providing heat to communities.  With fossil fuel prices rising in recent years, the attractiveness of an EfW component of the portfolio is likely to grow.

CIWEM considers that wider utilization of the energy value of residual waste before final disposal would make a sensible and more sustainable contribution to our energy policy.  Refuse derived fuels could, with the right development, provide energy at stable prices for industrial purposes.

The Government has emphasized the importance of the role combined heat and power (CHP) can play in the future energy mix.  The UK Government and the Office of Gas and Electricity Markets (Ofgem) are to undertake a comprehensive review on distributed energy including CHP, which will report in 2007.  The Renewables Obligation Order 2006 made EfW derived CHP eligible for Renewables Obligation Certificates (ROCs) and those which are compliant with Combined Heat and Power Quality Assurance are eligible for ROCs on all their biomass-generated energy.  Government guidance states that Municipal waste management strategies should drive proposals for new EfW plant, within the context of diverting wastes further up the waste hierarchy, and seek to maximize the benefits of any new plant such as CHP for neighbouring communities.  The Waste incineration Directive states that heat should be used 'as far as practicable'.

Climate Change / Greenhouse Gas Emissions

The UK Government has stated in its review of the Waste Strategy that EfW reduces emissions of greenhouse gases, through diversion of waste from landfill which would otherwise generate the powerful greenhouse gas methane during waste decomposition.  Furthermore, emissions from the biomass fraction of waste are considered by the Government to be carbon neutral with the energy recovered displacing that otherwise likely to be produced from fossil fuels.  The Government claims that "these advantages clearly make EfW a valid option for waste management towards the lower end of the waste hierarchy"2.

Debate surrounds whether combustion emissions from biomass (biogenic or short-cycle carbon, which is contained in material such as paper and card, kitchen and green waste, residuals of which may still be present when incinerated) should be considered carbon neutral.  The reasoning is that such carbon was taken up recently by the biomass when it grew, and if such materials are grown sustainably an equilibrium is reached between carbon taken up from and that released to the atmosphere.  The waste fraction comprising materials originating from fossil fuels (e.g. plastics) is considered to produce non-biogenic, or long-cycle carbon, which prior to combustion was stored underground for a long time and hence is regarded as a net addition to the atmosphere and the key source of anthropogenically induced climate change.

A recent study by WRAP3 claims that even when the assumption is made that biogenic carbon from kitchen waste and paper is carbon-neutral, EfW without CHP produces significantly more CO2 equivalent per kilowatt hour than gas fired power stations.  Incinerators are also generally less efficient because energy is expended in removing moisture from the refuse and in scrubbing pollutants from flue gasses.

There have been two recent reports considering the impact of EfW on greenhouse gas emissions / climate change.  The first, by ERM for Defra4 (to accompany the 2006 review of the Waste Strategy) investigates a range of scenarios and likely responses to the EU Landfill Directive.  It estimates greenhouse gas emissions for these, and shows that scenarios with high levels of recycling, EfW, and MBT with RDF combustion show greater net greenhouse gas benefits.   However, process emissions of carbon dioxide from EfW in the study were based on the non-biogenic component of the waste stream and did not count biogenic carbon.

The second report, by Eunomia5 for Friends of the Earth (FoE), challenges the view that energy recovery from waste will have beneficial effects on levels of greenhouse gas emissions.  This view, it claims, is subject to a range of assumptions which can have a significant impact upon the outcome of studies.  It claims that conventional life cycle assessment approaches are not necessarily appropriate, particularly how they consider the issue of the time profile of emissions.  It also casts doubt on the appropriateness of removing biogenic carbon from the equation, stating that the climate responds no differently to biogenic or non-biogenic CO2 and that much of the energy recovered in EfW is from non-biogenic carbon in plastic waste residuals.  It states that under assumptions widely employed in work for Defra, EfW where only electricity is generated (as is the case in the UK) is only marginally better than landfilling.

Discussion

The UK must comply with European regulation to significantly reduce the amount of mainly biodegradable municipal waste disposed of to landfill.  Even with good delivery against these requirements, additional ways of disposing of waste are likely to be required barring dramatic improvements in waste minimisation levels.  Recovering energy from waste represents a practical way of treating it, and CIWEM considers that, particularly if combined with heat recovery through CHP, Energy from Waste does have a role to play.  There is ample evidence from Europe that EfW can coincide happily with high levels of recycling and CIWEM does not consider that investment in improved and expanded EfW would hamper efforts to increase recycling rates or reduce waste production.

If CHP is to be more widely utilised with EfW, there will need to be greater emphasis on its encouragement at a strategic level.  Planning bodies should consider new developments with a more favourable attitude towards their integration with CHP programmes both large and small.  There would be benefits to be gained if new developments were planned in such a way that they could take advantage of CHP technology at an appropriate scale (power and heat is far more efficient than power only).  There have been calls for fast-track planning of new EfW infrastructure, but CIWEM considers that any new facilities should be required to go through the full and proper planning process.

Issues of public health impacts are likely to remain contentious with opinion split.  The Health Protection Agency's position is that the Waste Incineration Directive should ensure that health effects are unlikely, and that incineration of municipal waste accounts for less than 1% of UK dioxin emissions.  At the other end of the scale, Friends of the Earth claim that much of the population are already exposed to unacceptable levels of dioxins, therefore new additions to such emissions should not be permitted.

CIWEM considers that the Government should work on developing greater public appreciation of the health risks posed by EfW in the context of other commonly occurring processes and pollutants (e.g. the fact that about 14% of UK dioxin emissions are produced on bonfire night is probably not widely appreciated).  The measurement of the impact of combustion plant in terms of deaths brought forward does nothing to allay these fears and is something of a risk perception gaffe.  There is a need to measure the impact of all waste management facilties in the same way and to be somewhat more positive about communicating them to the public. CIWEM considers that the emissions from such plant are insignificant in comparison with conventional power plant, whose emissions are much less tightly controlled.  Despite this it is likely that opposition will remain which will make planning for new facilities a long and drawn-out process.

There is an ongoing debate regarding the relative merits of EfW and landfill in terms of their contributions towards greenhouse gas emissions and therefore climate change.  Nevertheless, CIWEM considers it a positive move that EfW with CHP may be eligible for ROCs and considers that a technology which diverts a proportion of waste from landfill and at the same time replaces conventional fossil fuel and generates electricity and usable heat should be supported.

CIWEM considers that the use of high quality RDFs is entirely prudent.   Much can be gained through cooperation between industry and regulators in the agreement of protocols and quality criteria for RDFs on a Europe-wide level.  High quality RDFs could provide a source of fuel which is cleaner than much of the coal burned in power stations and furnaces in the UK and therefore should be encouraged, when burnt in Waste Incineration Directive compliant plants.  The Institution contends that if this approach is adopted, there will be negligible health impacts on the public, although perceptions may be hard to change.

References

  1. Defra, Municipal Waste Management Statistics 2004/05, March 2006
  2. Defra, Review of England's Waste Strategy - A Consultation Document, February 2006
  3. WRAP, ENVIRONMENTAL BENEFITS OF RECYCLING An international review of life cycle comparisons for key materials in the UK recycling sector, 2006
  4. Defra, Impact of Energy from Waste and recycling Policy on UK Greenhouse Gas Emissions - Final Report, January 2006.
  5. Eunomia Research & Consulting, A Changing Climate for Energy from Waste? Final Report for Friends of the Earth, May 2006

October 2006

Note: CIWEM Policy Position Statements (PPS) represent the Institution's views on issues at a particular point in time.  It is accepted that situations change as research provides new evidence.  It should be understood, therefore, that CIWEM PPS's are under constant review, that previously held views may alter and lead to revised PPS's.

 

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Chartered Institution of Water and
Environmental Management (CIWEM)

106-109 Saffron Hill, London, EC1N 8QS  
Tel: 020 7831 3110 Fax: 020 7405 4967

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