Greenhouse gas emissions from waste disposal

From Statistics Explained

Data from March 2014. Most recent data: Further Eurostat information, Main tables and Database.

This article takes a look at one example of a waste-related environmental impact, the emission of greenhouse gases (GHG) in the European Union (EU) and some EFTA and candidate countries as a result of waste disposal operations such as landfilling, incineration without energy recovery and other treatment operations such as composting. It is widely recognised that managing waste has a range of potential environmental impacts and, as Eurostat collects and collates basic data on waste generation and treatment, the emission of greenhouse gases can be analysed in some detail.

The data were obtained from the European Environment Agency (EEA) and EEA reports prepared for the United Nations Framework Convention on Climate Change (UNFCCC). It should be noted that waste nomenclatures may differ: incineration in this context covers only incineration without energy recovery.


Main statistical findings

Figure 1: Estimated share of the three waste disposal operations in GHG emissions (2011) - Source: EEA Greenhouse gas data viewer, March 2014

Six greenhouse gases are identified under the Kyoto Protocol: carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), and three fluorinated gases. More information is available from the European Commission's Directorate-General for Climate Action and the EEA. Data for other countries can be found on the UNFCCC website.

Relevance of the waste sector

Table 1: Variation of emissions by major source category, 1990-2011, in million tonnes per year - Source: Annual EU greenhouse gas inventory 1990-2011 and inventory report 2013, 27 May 2013 EEA

Table 1 gives an overview of changes in GHG emissions broken down into major sources. For the EU-15, the total reduction achieved in 2011 amounted to 624 million tonnes CO2-eq/year, or 14.7 % since 1990 (when GHG emissions were 4 244.8 million tonnes CO2-eq/year). While some sources e.g. the road transport sector, still show an increase in GHG emissions, others, such as industrial processes, household & services, and waste disposal, show a decrease.

The EEA forecasts that emissions from waste disposal will decrease further in the future, despite a steady increase in the overall quantity of waste being generated. This shift stems from the decrease in waste being landfilled in the EU. The waste sector accounted for about 11 % of the cuts in GHG emissions in 2011, which amounts to 1.8 % of total emissions. The waste management sector therefore plays a key role due to the reduction in reliance on landfill for residual disposal - a change that has been significantly influenced by EU waste legislation (see Outlook below).

Waste disposal operations

Official reporting to the Secretariat of the United Nations Framework Convention on Climate Change (UNFCCC) involves a breakdown of emissions from solid waste disposal into three subcategories:

  • Sector 6A - landfill;
  • Sector 6C - incineration without energy recovery; and
  • Sector 6D - other treatments such as fermentation/composting.

It should be noted that carbon dioxide (CO2) emissions from organic (biogenic) carbon are not entered in the 'accounts', but methane (CH4) emissions from biogenic carbon are.

Sector 6A - Landfill

The emissions from landfill sites are not measured but modelled, as detailed in the IPCC guidelines on waste. Methane is emitted from landfill sites as fugitive emissions. The models used take into account the local weather conditions (humidity and climate), which have a high impact on the overall process. A simple model may divide the landfill process into three steps:

  1. during the initial active phase, the degradable portion of the landfilled waste undergoes both aerobic and anaerobic degradation; as the landfill is not sealed during this phase both methane and biogenic carbon dioxide are emitted;
  2. once the landfill has been sealed, the 'methanogenic' phase takes place and the landfill gas contains greater quantities of methane than in the first phase;
  3. finally, as different types of carbon degrade at different rates (sugars and fat degrade relatively quickly, while cellulose degrades more slowly) and there is very little degradation of lignin products (contained in wood) in landfill, these materials may not degrade appreciably even over much longer time periods.

Stopping landfill today, therefore, would not put an end to methane emissions immediately and as such, but a slow decline in methane emissions from old landfill sites would become apparent. A key measure to mitigate methane emissions is the capture of the methane, especially during the second phase, and its subsequent combustion to produce energy. Methane is combusted to carbon dioxide, which is not entered in the inventory (organic carbon). In the United Nations Framework Convention on Climate Change (UNFCCC) reporting system, the methane emitted to the atmosphere is entered in the 'accounts'. However, the benefits stemming from energy production from methane gas capture at landfills and the utilisation of this gas are accredited to the energy sector, rather than the waste sector.

Sector 6C - Waste incineration without energy recovery

During waste incineration, fossil carbon contents (from, oil products such as plastics), are emitted and recorded. Biogenic carbon from paper waste (e.g. newspapers), wood and biowaste is also emitted but not entered in the 'accounts'. Other types of GHG emission are negligible. Emissions from waste incineration with energy recovery are ascribed to 'energy' rather than 'waste'. Therefore, in the event of energy recovery, the extent of such emissions from incineration with energy recovery cannot be established. As a result, a full comparison between different waste treatment operations is not possible because the benefits from improved waste treatment, such as incineration 'with energy recovery' (and the subsequent avoidance of equivalent energy production, e.g. from fossil fuels) are not fully demonstrated in the waste sector under UNFCCC reporting.

Sector 6D - Other waste disposal / treatment

Other treatment options, e.g. the composting or fermentation of biowaste and/or mixed waste, and the recycling or pre-treatment of waste for landfill, may give rise to fewer methane or nitrous oxide emissions.

Figure 1 is as a pie chart presenting the estimated proportions of greenhouse gas emissions from the three types of disposal/treatment operation in 2011.

This shows that 95 % of the GHG emissions from waste management come from the landfill sector, while the other two types of operation contribute only 5 %. However, it should be noted that the incineration section includes only facilities without energy recovery so overall only a fraction of incineration emissions are presented in the chart. It is therefore reasonable to focus on landfill.

 Time series of GHG emissions from the waste sector

Figure 2: GHG emissions in EU-15 and EU-28 for landfill and the sum of incineration without energy recovery and other treatments from 1990 to 2011 (1 000 tonnes) - Source: EEA GHG data viewer
Figure 3: Per-capita GHG emissions in 1990 and 2011 for landfill, EU-15 Member States (kg CO2-eq / year per person) - Source: EEA GHG data viewer
Figure 4: Per-capita GHG emissions in 2011 for landfill, non-EU-15 countries (kg CO2-eq / year per person) - Source: EEA GHG data viewer

Products from fossil oil, such as plastics, are assumed not to degrade in a landfill site because of the length of the degradation process. This extends the observation time frame for global warming (usually 100 years). Organic carbon may decay in the presence of oxygen (aerobically) to carbon dioxide or decompose in the absence of oxygen (anaerobically) to carbon dioxide and methane. As methane has a greater impact than carbon dioxide, methane emissions are recorded as anthropogenic emissions.

Figure 2 shows the time series for greenhouse gas emissions from 1990 to 2011. The two smaller subcategories (incineration without energy recovery and other treatments) are summarised. Data is shown for the EU-15 and theEU-28.

In the early 1990’s, greenhouse gas emissions from landfill decreased slowly. Between 1995 and 2005, there was a high rate of reduction, but since 2005 there has been slower progress in cutting emissions. Over the reporting period, total EU-15 emissions from incineration without energy recovery and other treatments have remained quite stable, at approximately 5 million tonnes CO2 equivalent a year. Emissions from incineration without energy recovery are declining, whereas those from other treatment activities are rising and have been at a level of 2.0 million tonnes a year since 2007.

Developments in GHG emissions per capita in the landfill sector for each EU-15 country are shown in Figure 3. Overall, these fell by 51 % from 1990 to 2011. Spain, Greece and Portugal show higher emissions in 2011 than in 1990. In 2011, emissions in Spain, Finland, the United Kingdom, and Portugal were significantly higher than the EU-15 average. Per-capita emissions in Belgium and Luxembourg were just half the EU-15 average in 2011.

Figure 4 gives an overview of the GHG emissions from landfill in 2011 in the other Member States than EU-15 Member States and the candidate countries.

GHG emissions from landfill in the EU Member States that joined the EU in 2004 and after are in general (with the exception of Romania) higher than, or close to the EU-15 average (in the cases of Estonia, Poland, Croatia, and Slovenia). Only Bulgaria, Cyprus, Slovakia, Malta and Hungary are significantly above the average. Overall, the EU-28 average differs only slightly from the EU-15 average. Iceland and Turkey show significantly higher emissions per capita.

 Outlook

Figure 5: 2006, 2009, 2011 landfilling of biodegradable waste as a percentage of the 1995 biodegradable waste generation - Source: EEA
Figure 6: 2006, 2009, 2011 landfilling of biodegradable waste as a percentage of the 1995 biodegradable waste generation; countries with derogation status - Source: EEA

By adopting Landfill Directive 1999/31/EC, the European Union gave itself a powerful tool for reducing the amount of biodegradable municipal waste going to landfill. It is this fraction of the waste that accounts for for methane emissions. The Directive requires the collection and incineration of landfill gas and the monitoring of landfill gas emissions. Flaring is also an option for older landfills, as it neutralises methane emissions (biogenic CO2 is not entered in the 'accounts', but methane is).

Article 5 of the Directive sets targets for reducing the volume of biodegradable municipal waste sent to landfill. These are expressed as percentages of this waste generated in 1995, as follows:

  • 75 % in 2006;
  • 50 % in 2009; and
  • 35 % in 2016.

Member States that landfilled more than 80 % of their municipal waste in 1995 may postpone the attainment of these targets by no more than four years. Among the EU-15 countries, the United Kingdom, Ireland and Greece have been granted a derogation period. Among the countries that joined the EU in 2004 or later Hungary is not covered by the derogation.

Member States may adopt various strategies to reduce the amount of biodegradable municipal waste going to landfill:

  • the recycling of biodegradable waste - paper/cardboard, wood;
  • the recycling of organic waste via composting;
  • the recovery of biodegradable waste via fermentation, anaerobic digestion, pyrolysis; and
  • incineration.

From the existing Eurostat data it is not possible to track the reduction in biodegradable municipal waste, as only the total amount of municipal waste sent to landfill is monitored. The definition of biodegradable waste, the national strategies for reducing landfill and a limited set of data are published in a report on the implementation of the Landfill Directive. A summary and update on biodegradable municipal waste is given in EEA. The 2006 data is also discussed in the State of the environment report No 5/2010 on Material resources and waste and in the update to the European Environment State and Outlook 2010.

Figure 5 shows the percentage of landfilling of biodegradable municipal waste in 2006, 2009 and 2010, and the targets for 2006, 2009, and 2016. Figure 6 shows the same for countries with a derogation period (targets postponed to 2010, 2013 and 2020).

Eleven of the EU-15 Member States report levels below the 2009 target of 50 %. For Italy, the level is slightly higher (57%), and for Portugal (78%), Ireland (94%) and Greece (108%) substantially higher. The last three countries have received a derogation of up to four years to achieve the target (i.e. by) 2013. Among the Member States that joined the EU in 2004 and after, Bulgaria, Hungary and Estonia met the target in 2009. All Member States that joined the EU in 2004 and after have received a derogation with a 2010 target of 75%. Nine countries with derogation status have not met the 2010 target: Portugal (80%), Lithuania (81%), Poland (84%), Latvia (86%), Malta (96%), the Czech Republic (97%), Greece (108%), Croatia (129%), and Cyprus (134%). By 2010 seven EU-15 countries (Germany, Austria, Denmark, Belgium, Sweden, the Netherlands and, Luxembourg) had already reached the 2016 target (35%). Finland and France were close, with 37% and 38% respectively.

Data sources and availability

The official greenhouse gas emission inventories for the EU and the individual Member States are submitted to the United Nations Framework Convention on Climate Change (UNFCCC) in two parts:

  • Common reporting format (CRF) – a series of standardised data tables containing mainly numerical information and submitted electronically;
  • National inventory report (NIR) – a comprehensive description of the methodologies used in compiling the inventory, the data sources, the institutional structures and quality assurance and control procedures.

The report and data are available 15 months after the reporting year has ended. Data for other countries is also documented at the UNFCCC Secretariat.
The EU reports and condensed tables are also available at the EEA. The EEA maintains a combined database ( GHG data viewer).

More information is available from the European Commission's Directorate-General for Climate Action and the EEA.

Context

The Kyoto Protocol is an international agreement that includes legally binding GHG emissions targets for the industrialised countries. It aims to achieve an overall reduction of at least 5 % from 1990 levels in the period 2008-12. The Protocol sets individual targets per country, but the 15 EU Member States (EU-15) at the time it was adopted (1997) agreed to an 8 % reduction and re-distributed this target under the burden-sharing agreement (Council Decision 2002/358/EC).

Bulgaria, the Czech Republic, Estonia, Latvia, Lithuania, Romania, Slovakia and Slovenia also took on the 8% target. Poland and Hungary will have to reduce emissions by 6%. There is no legal EU target for Cyprus and Malta.

The UNFCCC definition of the waste sector differs from, and is narrower than, the definition of waste management in EU waste legislation and the EU Waste Statistics Regulation. This report follows the UNFCCC reporting system and classification.

Note that the term 'incineration' covers only 'incineration without energy recovery' in GHG accounting. Waste incineration with energy recovery is classified as an energy process in GHG accounting and cannot be isolated from other energy processes. Therefore, the greenhouse gas emissions from 'incineration' as registered in GHG reporting represent only a fraction of those from the 'incineration with or without energy recovery' processes normally covered under waste legislation. The term 'other processes' refers to pre-treatment processes such as fermentation or composting.

If the full range of impacts from waste management operations are to be investigated, a different approach is needed. This should take into account all emissions caused or avoided by waste treatment, i.e. direct emissions from all waste treatment types, including recycling, incineration and landfilling; moreover, the recovery of energy ( from incineration, landfill gas and anaerobic digestion plants) and materials (by recycling, composting and anaerobic digestion) primary production of energy (e.g. from fossil fuels) and virgin materials (virgin paper, metals, etc.). In order to demonstrate the full effect of waste management, emissions inventory reporting should take account of the emissions thus avoided. See EEA publication for an example of how this 'life-cyle' approach can be applied to municipal solid wase in the EU.

See also

Further Eurostat information

Publications

Main tables


Database

Methodology / Metadata

Source data for tables and figures (MS Excel)

External links

Views