Climate Change Committee WG1

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Climate Change Committee WG1

• Comparison of uncertainties in the waste sector
  reported by Member States
• Odette Deuber, ETC-ACC
• 3 May 2005

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Uncertainties regarding activity data CRF 6.A
Solid Waste Disposal)
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Uncertainties for Emission FactorsCRF 6.A Solid
Waste Disposal
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Activity data, emission factors and combined
uncertainties (6.A)
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6.A Solid Waste Disposal parameters effecting
key uncertainties

• Quantity and composition of landfilled waste
• waste composition may change over time
• actual emission estimates are still dependent on
  data extrapolations from earlier years which are
  in general of lower quality
• Data of industrial waste is often of lower
  quality
• Quantity of CH4 that is actually generated
• Small changes in the assumed DOC value can result
  in large variations.
• DOC values are widely differing among Member
  States (as different waste compositions)
• DOCf
• Assumed half-life or k (methan generation rate
  konstant)
• Quantity of CH4 that is actually emitted
• Degree of oxidation that occurs as the gas
  diffuses through the landfill cover materia
  (presence, thickness and other characteristics of
  SWDS cover material).
• Methane recovery

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6.B Default uncertainties according to IPCC GPG

• Activity data (6.B.1)
• Industrial production - 25 expert judgement
  needed
• COD/ t product very uncertain 50, 100
• Activity data (6.B.2)
• Human population - 5
• BOD/ person - 30
• Emission factor
• Maximum CH4 Producing Capacity Bo - 30
• Fraction treated anaerobically expert judgement
  needed

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Uncertainties regarding activity data CRF 6.B
Wastewater Handling

1. Sparsely populated areas
2. Densely populated areas

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Uncertainties regarding emission factors CRF 6.B
Wastewater Handling

1. Sparsely populated areas
2. Densely populated areas

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Activity data, emission factors and combined
uncertainties (6.B)

1. Sparsely populated areas
2. Densely populated areas

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6.B Wastewater handling parameters effecting key
uncertainties

• Organic waste water quantity and composition
• Often amount of DOC in the wasteater that is
  produced and the volumes handled in the various
  systems are often not well known.
• DOC values in industrial sector are often
  averages from several processes.
• Wastewater handling facility efficiency and
  output
• Aerobically treated wastewater by handling plants
  may be subject to anaerobic conditions due to
  poorly managed and functioning facilities.
• Efficiency of CH4 recovery / flaring
• Data on lagoons are very limited.

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Determination of Uncertainties for EU inventory

• depending on correlation between the MS
  uncertainties
• Relative uncertainties if it is assumed that they
  are
• not correlated 14.3 (6.A) 30.3 (6.B)
• correlated 41.8 (6.A) 63.5 (6.B)
• Assumption made
• Uncertainties of Member States correlate if
  either Default EF or T1 as method were applied.

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How to improve uncertainty estimates?

• Each Member States should check uncertainties
  relative to IPCC default values.
• Improvement of data quality regarding parameters
  affecting key uncertainties.
• Let us discuss...

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• Thank you for your attention