European Court of Justice Conditions for Energy Recovery in Waste-to-Energy Plants

Interpretation of par. 32 - 34 of the Judgement

1. Preface

The conditions for energy recovery (point R1 of Annex II B to the Waste Framework Directive) are given by the European Court of Justice in the above mentioned Judgement in par. 32 - 34.

2. Paragraphs 32 - 34

Par. 32 - 34 contain conditions that are to be examined cumulatively.

The process of energy recovery ("Use principally as a fuel or other means to generate energy" (R1 of Annex II B to the Waste Directive) includes the combustion of waste, if:

If these conditions are fulfilled, energy recovery in waste incinerators takes place.

Given the following assumptions on the individual conditions, a generalised model is used. Deviations are possible. In all other respects the BREF documents could be helpful for the determination of the values necessary.

2.1. par. 32

Here, the principal purpose is relevant. The wording "essential purpose" is to be understood as being goal-oriented (see the French version "finalité essentielle").

2.2. par. 33

• Generation of Energy: Energy is generated in the combustion chamber. The energy content in the steam from the boiler amounts to 75% - 85%. The initial energy content is 100% in the combustion chamber. From this 15% - 25% energy loss is to be subtracted for the exhaust gas loss and the bottom ash (3% bottom ash and 12% - 22% exhaust gas loss).
  
  
• Recovery: 75% to 85% of the initial energy content is recovered. This approximately corresponds to the boiler efficiency. The energy recovery can be utilised both for the self demand and for the export of energy. The "recovered energy" thereby corresponds to the total energy content of steam produced in the boiler.
  
  
• Consumption: The consumption of energy takes place in the combustion chamber (e.g. movement of grates, transportation of bottom ash, insert of auxiliary burner).
  
  The attribute "consumption" requires a remaining residue of over 50%. On the basis of an energy consumption of a maximum of 20% for subsistence, taking into account a boiler efficiency from 75% to 85%, the content of energy that can still be delivered amounts to 55% to 65% (75% to 85% minus 20%).
  
  Therefore more energy is generated and recovered (approximately 85%) by the combustion of waste than is consumed by the combustion process.
  
  
• Effective and partial use of the energy surplus: After the subtraction of the energy content used for both the boiler and subsistence, there is still an usable energy surplus from 55% to 65% remaining.

2.3. par. 34

• Consumption of the greater part of waste: In contrast to par. 33, the term "consumption" in par. 34 means the combustible fraction in relation to the inert fraction and probably serves the argument, whether waste is more material or more energetic. The residue of cinder and boiler ash remaining, must amount to < 50% related to the quantity of waste that has been used. During the process of combustion the larger part of waste is consumed, because one ton of MSW generates 1 - 3 weight percentage of ACP (air pollution control) residues and 25 - 30 weight percentage of bottom ash (which is recovered).
  
  
• Released Energy: The content of energy released amounts to 97% (100% in the combustion chamber minus 3% energy loss for the bottom ash). The larger part of this amount must actually be utilised.
  
  
• Reclamation of the greater part of energy released: As mentioned above, between 75% and 85% of the initial energy content is recovered, whereby the energy recovered can principally be used for both subsistence of the plant and the delivery of energy.
  
  
• Actual use of the greater part of Energy: If 75% to 85% of the energy is recovered and further 20% is subtracted for the subsistence, there is still 55% to 65% of energy surplus left over. Therefore the larger part of energy (released and recovered) can actually be used.
  
  Assuming that nearly 30 million tons of wastes are treated/year in the Waste-to-Energy Plants, represented by CEWEP, the annual substitution of fossil fuels, such as natural gas are 4.67 billion m³ and 4.58 billion litres of oil.

St / 20 May 2003

(1) The European Court of Justice remarked (par. 34) that waste is used principally as fuel or other means to generate energy, if the larger part of the waste (= more than 50 %) is used with the procedure of combustion and if the larger part of energy set free (= more than 50 %) is recovered and utilised.