About Task 36

Rationale

Waste management continues to face challenges in many areas, including the treatment of the waste, resource recovery and disposal. Increasingly Governments are looking at opportunities to recover value from waste that cannot be recycled.  In a number of countries attention on energy recovery, particularly heat, has increased.  This development of policy at national and local level is one of the most important influences on the recovery of energy from solid waste, together with barriers to procurement and energy use. 

Waste management policy and the drivers for development of waste management are summarised in Table 1 and discussed in the section below.  A key role of the proposed work for Task 36 will be to examine how these policy differences influence the development of energy from waste, particularly recovery of heat and integration of energy recovery from solid waste with other materials recovery and waste treatment processes.

EfW: energy from waste; GHG: greenhouse gas; MSW: municipal solid waste

Developments in the EU

Within the EU policy drivers for waste disposal and renewable energy generation dominate the development of waste management.   The EU’s main policy driver for waste management continues to be the diversion of biodegradable waste from landfill, as required under the Landfill Directive.  The options for diversion from landfill are focused by two factors:

1. Local waste disposal regimes, which are either dominated by landfill (e.g. UK, Ireland and many southern and Eastern European Member States) or by a highly developed waste management structure (e.g. in Denmark, NL and Germany), which dictates local options.
2. The Waste Hierarchy developed within the revised Waste Framework Directive, which encourages prevention, recycling and reuse above recovery, treatment and disposal. The changes in the Waste Framework Directive have introduced a focus on application of life cycle assessment to waste management systems.  This is important in that it influences thinking on resource recovery from solid waste in Europe.  For example, it can contribute to comparison of options for the residual fraction of solid waste after recycling, providing an indication where it makes sense to recover energy, particularly with highly efficient CHP plants.

The Waste Hierarchy influences the options for waste management across the EU. As the report of the current Task 36 shows, after extraction of recyclable components there remains a significant residual waste stream with considerable potential for energy recovery.  The challenge in many EU Member States is to develop current practices to allow for good quality recycling and optimal recovery of resources from the residual waste management stream. A number of options are being examined across the EU, but many of them have in common the production of a residual fraction which is often referred to as solid recovered fuel (SRF) or refuse derived fuel (RDF).  These fuels may be proposed for use in cement kilns, coal and biomass co-firing and their processing and preparation will be dependent on the end use. These trends are also reflected in an increasing interest in the development of ‘eco refineries’ at waste treatment sites in some countries.  Eco refineries include a number of technologies to recycle and recover resources from waste, including energy, on one site. There are also opportunities for the biological treatment of specific waste streams including the anaerobic digestion of the organic fraction of waste and source separated food waste, with subsequent energy recovery.

An additional EU policy that might have a significant impact on waste to energy in the near future is the recent Renewable Energy Directive, which sets targets for 20% renewable energy in the EU by 2020.  Within this Directive the ‘biogenic’ or biodegradable fraction of waste is included as a renewable resource; and there are incentives to encourage the production of biofuels from waste feedstocks (including municipal, commercial and industrial waste).  This, together with the focus on life cycle assessment in waste disposal, incentivises the development of ‘eco-refineries’ further, to include an element of heat recovery as well as production of potential chemicals for biofuels. 

These are interesting times for Europe, with the scope for considerable increase in energy from waste in some regions, rationalisation of waste treatment and potential development of advanced processing facilities designed to optimise energy recovery integrated with use of heat and development of feedstocks for biofuels. To achieve this there are a number of key issues that need to be addressed, such as

• the definition and measurement of the ‘biogenic’ fraction of MSW, to enable measurement of eligibility within the Renewable Energy Directive;
• the management of residues from recycling so that they are suitable for combustion and the development of standards for the use of RDF and SRF, particularly their co-firing with biomass;
• assessment of the GHG reduction potential for key options for waste management compared with energy recovery;
• ensuring that energy from waste does not add to environmental burdens in any other way;
• whether we can achieve cost effective and replicatable higher efficiencies from solid waste power generation; and
• the potential for heat use – and the investments that are necessary to realise the potential for heat generation; and how this heat may also be used effectively for chilling applications.

North America

Canada and the USA continue to rely on landfill and do not yet have national policy measures to mirror the EU landfill Directive.  Despite this, it is increasingly becoming apparent in these countries that long term reliance on land fill is not sustainable.  Some States in the north USA are concerned about landfill void space and there are trends to improve recycling and composting of solid waste. In Canada there are particular issues in introducing energy recovery from solid waste in rural areas where the waste generated is low.  This is a common problem in rural areas across the world (including the Nordic and Eastern European States) and there is increasing interest in finding cost effective small scale solid waste energy recovery systems.

In addition there are other drivers for the recovery of value from waste.  For example, the USA has an increasing drive to use waste feedstock (including resources from solid waste) for biofuels.  The recent DOE Multi Year Program Plan for biofuels includes many pointers to the value of waste as a feedstock for biofuels (particularly in biorefineries).  While solid waste is not the only (and certainly not the main) feedstock for this program, its potential has been recognised and the plan will examine the potential for mobilisation of this resource over the next three to eight years. 

Rest of World

Internationally, Japan is significant in that it is highly dependent on energy from waste (80% of its waste went to incineration in 2007).  Many Japanese plants are small scale incinerators with no energy recovery and Japan is undertaking a programme to replace many of these plants with modern systems including energy recovery.  This means that there is a large potential for high efficiency energy recovery in Japan and it has been in the forefront of the development of advanced treatment of municipal waste, such as gasification systems and the development and use of refuse derived fuel. 

Australia traditionally relies on landfill but has recently agreed to examine a national waste policy to address the country’s increasing waste production.

Thus it is an interesting time for the development of energy from solid waste.  There are both environmental and climate change drivers to improve the use of the resource in waste and these have spurred interest in integrating combustion technologies with other resource recovery from solid waste. 

Policy makers are increasingly interested in the potential to develop waste and resource management systems that are environmentally and economically sustainable and that integrate with drivers to increase renewable resources and renewable energy in particular. 

The Task 36 (2010-2012) work plan reflects these trends.  The Task will collate the most relevant recent research work and produce guides on developments in relevant areas, including resource management; efforts to produce quality standards for SRF and RDF; policies to support the use of heat from energy from waste plants.  It will also undertake work on the life cycle analysis of waste management and energy recovery compared to other issues; and it will revise and update work on emissions of fine particulates from energy from waste.