The European Commission is seeking to examine the energy efficiency of waste-to-energy plants in order to classify them as either recovery or disposal. Under the new criteria, many of Europe’s existing plants would be deemed ‘disposal’. Yet how realistic is this criteria, and what would it mean for the waste-to-energy industry?
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by Ella Stengler
On 21 December 2005, the European Commission proposed a review of the 1975 Waste Framework Directive. As part of this revision, the Commission wants to clarify the definition of recovery and disposal. The principle of ‘replacement of resources’ remains decisive when defining recovery; recovery operations should serve a useful purpose in replacing (‘whether in the plant or in the wider economy’) other resources that would have been used to fulfil that function.
In a case in 2003,1 the European Court of Justice considered only the boundaries of a plant itself and thus stigmatized a municipal waste incineration plant as a disposal operation. However, substitution is now assessed from an economic perspective, enabling waste-to-energy (WTE) plants to be classified as energy recovery facilities if the energy efficiency criteria described in Annex II of the Waste Framework Directive (see box) are fulfilled.
What does this mean in practice?
The Confederation of European Waste-to-Energy Plants (CEWEP) welcomes the Commission’s approach in principle. However, CEWEP is concerned about the energy efficiency factor proposed by the Commission.
An energy efficiency factor of 0.6, which has been proposed by the Commission, is too high for most existing plants. A threshold of 0.5 would be sufficient, with a further reduction of 0.1 for small plants and plants that produce electricity only due to a lack of demand for heat.
A factor of 0.6 would disadvantage smaller plants as they generally need the same energy for operation as larger plants, but have a lower throughput. It should be noted, at this point, that the public tend to prefer smaller plants in order to reduce the distance waste is transported.
Southern European WTE plants have little or no demand for the heat they produce and, as a result, an efficiency factor larger than 0.5 would discriminate against plants in these climates. This is not the case in northern Europe, particularly in Scandinavian countries, where extensive infrastructure for district heating exists.
High energy efficiency can only be realized under local conditions where there is a demand and an economically viable market for the kind of additional energy produced. For district heating, the infrastructure and access to the grid are very important because heat, unlike electricity, cannot be transported long distances.
Therefore, it is necessary for the consumers for the heat to be close to the plant. But due to a lack of public acceptance, WTE plants have quite often been forced to be constructed away from urban areas and far away from potential consumers.
CEWEP hopes that this attitude will change in the future, bearing in mind that fears about harmful emissions can be dispelled. Modern WTE plants operate with minimal emissions,2 complying with the strict emission limit values laid down in the Waste Incineration Directive (2000/76/EC).
WTE plants should be located in areas where they can deliver the heat generated from the waste to their neighbourhood. In addition, district heating networks should be improved. If this happens, the energy efficiency threshold can be higher for future plants, but should be reasonable for existing plants (0.5 rather than 0.6).
WTE efficiency in Europe
CEWEP has assessed the energy efficiency of 97 of its member WTE plants.3 The plants investigated offered a combined capacity of 24 million tonnes of municipal solid waste (MSW), representing 27% of the total number of WTE plants in the EU and 49% of the EU’s WTE capacity.
Although it can be assumed that the most efficient WTE plants in Europe participated in CEWEP’s investigation, only 67 WTE plants achieved the energy efficiency threshold of 0.6 proposed by the Commission. This is not a large proportion, bearing in mind that there are about 420 plants in the whole of Europe and 359 in the EU.
An energy efficiency threshold of 0.5 instead of 0.6 could be achieved by a further 18 WTE plants (i.e. a total of 85 plants) out of the 97 plants investigated by CEWEP.
What does it cost to improve energy efficiency?
In the majority of cases, an increase in energy efficiency rates will be combined with medium or high levels of investment.
At present, the Twence WTE plant in the Netherlands combusts 300,000 tonnes of MSW per year. The plant generates about 200,000MWh/year of electricity, of which 163,000 MWh/year is fed into the grid,supplying around 50,000 households with electricity.
The plant currently has an average energy efficiency performance. To improve the efficiency of the plant to above average, it would be necessary to invest €13 million. This would increase the heat supplyby 200,000 MWh/year.
‘Although generalization is difficult due to the different situations and locations of WTE plants, it can be estimated that E10-20 million investment is necessary to improve energy efficiency by 0.1 point,’ explains Jan Rooijakkers, Managing Director of Twence. ‘Naturally, this is providing that the plant has already invested in the basics in order to recover energy through the combustion of waste.’
‘Twence is going to undertake this extra investment in energy efficiency for the two existing lines. Furthermore, Twence is going to build an additional third line aiming at an energy efficiency rate of 0.8. However, improvement is more difficult from an already high level than from a low level,’ Jan Rooijakkers points out.
Dutch MEP Dorette Corbey, who is the shadow Rapporteur for the Waste Framework Directive for the Socialists in the European Parliament, visited the Twence plant on 31 August 2006. She stated: ‘The recovery of energy from waste is sustainable, naturally under the condition that the plant in question complies with the highest environmental standards. In this respect, a high ambition for the waste sector is necessary and should be stimulated by European policy. We will support this via the revision of the Waste Framework Directive.’
How do efficient WTE plants help to protect the environment?
In brief, state-of-the-art WTE plants contribute to the reduction of carbon dioxide (CO2) emissions and help to ensure security of energy supply.
 In order to be considered ‘recovery’ operation, many existing WTE plants would need to invest in technologies to achieve higher energy efficiency |
Using energy from waste rather than energy from power and/or heating plants, fossil CO2 emissions could potentially be reduced by 600-1200 kg/MWh electricity and 250-600 kg/MWh heat (depending on the kind of primary fuel mix for electricity or heat/district heat production, and assuming that the energy is used as basic supply).3
Creating incentives to boost energy efficiency in WTE plants would therefore support climate protection by further replacing the combustion of primary (fossil) fuels. In addition, energy recovery status for efficient WTE plants would support the aims of the Landfill Directive (1999/31/EC) - that is, diverting waste from landfills. Through the generation of energy from waste, which would otherwise be landfilled, WTE plants help to protect climate by reducing the production of methane from landfills.
These benefits were highlighted by the Commission when asked by the European Parliament’s Environment Committee to outline the impacts of their proposal to use an energy efficiency threshold to distinguish between municipal solid waste incinerators (MSWIs) that are disposal installations from those that are recovery installations (WTE plants).
Commissioner of the Environment, Stavros Dimas, commented as follows in his response letter (dated 24 August 2006). According to the Commission, its proposal ‘will have the effect of classifying only the most energy-efficient existing MSWI as recovery installations. This will be a strong incentive for increasing the energy efficiency of future MSWI and will thereby contribute to reducing greenhouse gas emissions associated with the production of energy. It will also facilitate the move away from massive landfilling of waste which is a current practice in many Members States’.
In addition, Stavros Dimas supported the view that recycling and WTE go hand-in-hand: ‘As shown by the statistics reported by the Member States, increases in incineration of municipal waste with energy recovery do not correlate with low recycling rates. It is therefore unlikely that the proposal would negatively affect recycling levels’.
This view is supported by CEWEP country reports (available from its website at www.cewep.eu), which show that countries with high recycling levels also have high levels of WTE.
Why does it matter if it is recovery and not disposal?
According to the waste hierarchy, recovery has priority over disposal. Consequently, it would be counterproductive for European environment policy, which aims to divert waste from landfills, to give WTE plants the same classification as landfills - disposal.
In addition, we need to get the balance right. Currently we have the curious situation in which industrial plants that co-incinerate waste qualify for energy recovery status but do not have to comply with the same strict emissions limit values placed on the WTE industry. The energy demands of the flue gas cleaning systems in WTE plants that secure low emissions must also be taken into account when considering plant efficiency.
One should also note the potential impact of this point on the long-term security of waste treatment. Excluding WTE plants from recovery status would discourage future investment and consequently lead to greater dependency not only on landfills but also on industrial co-incineration plants. And how will waste be handled if, for example, the construction market (with its cement kilns) is depressed? Would we turn to landfilling once again?
 Dutch MEP Dorette Corbey (right) said that high-efficiency WTE plants deserve political recognition of their recovery status. photo: twence |
In the long-term, only WTE plants can give security to treat MSW permanently in an environmentally sound way.
Conclusions
In its impact assessment on the energy efficiency threshold for WTE plants, the Commission concludes by pointing out:
- ‘The most significant impact of the Commission proposal is on future investments. The ambitious energy efficiency benchmark will make investment in facilities environmentally more demanding and will improve the environmental impact of incineration’.
- ‘Future investment in more energy-efficient techniques will be encouraged because decision-makers and operators will seek to reach the recovery status. This is consistent with the Community policy on energy efficiency and will spread good practices developed mainly in the northern regions of the EU to the rest of the EU’.
- ‘Greenhouse gas emissions will be decreased through the production of electricity and heat’.
- ‘Innovation will be encouraged giving a first mover advantage to European industry that is likely to result in future technology export opportunities’.
Clearly it is up to the WTE plant operators to improve their energy efficiency and thereby help to fulfil European environment policy aims. However, it is now up to the decision-makers to set a clear course, by providing incentives for investment in this sector and supporting the production of energy from waste. In this regard, energy recovery status for WTE plants under realistic conditions is essential.
Dr Ella Stengler is Managing Director of Confederation of European Waste-to-Energy Plants (CEWEP), based in Brussels.
e-mail: ella.stengler@cewep.eu
Notes
- Judgment of the Court of 13 February 2003 in Case C-458/00: Commission of the European Communities v Grand Duchy of Luxembourg. Official Journal of the European Union, C83, p.2, 5 April 2003.
- Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Waste Incineration - a potential danger? September 2005. www.bmu.de/english/waste_management/downloads/doc/35950.php
- CEWEP Energy Report by Dieter Reimann, www.cewep.eu/studies/art131,223.html
Energy efficiency
The energy efficiency formula takes into account the energy generated by the plant and puts it in relation to the calorific value of the municipal waste. The energy introduced into the process from outside (such as fossil fuels or electricity) is subtracted. The energy efficiency can be improved by, for instance, reducing the input of fossil fuels.
According to the Commission’s R1 formula, the energy efficiency for WTE plants is calculated as follows:
- Ep is the annual energy produced as heat or electricity in GJ/year. It is calculated with energy in the form of electricity multiplied by 2.6 and heat produced for commercial use multiplied by 1.1.
- Ef is the annual energy input to the system in GJ/year from fuels contributing to the production of steam.
- Ew is the annual energy in GJ/year contained in the treated waste calculated using the lowest net calorific value of the waste.
- Ei is the annual energy imported in GJ/year, excluding Ew and Ef.
NB: For thermodynamic reasons, Ef must be deleted in the nominator of the equation as it is included twice - in the nominator and the denominator.
