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Landfill Gas Factfile
Key points
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Landfill gas comes from plant and animal waste rotting in the landfill site without oxygen
Landfill gas includes methane that can be burned for energy
Landfill gas adds to climate change if it just escapes into the atmosphere
Biodegradable wastes should be composted instead and increasingly they are.
Background information
 Rubbish sent to landfill sites, can be a source of a bio-gas called landfill gas that contains
methane.
 Anaerobic bacteria (that live without Oxygen) in landfills, decompose the bio-degradable
wastes to produce the biogas.
 Methane is the same energy-rich gas that is in natural gas, and can be used for heating,
cooking, and producing electricity.
 Landfill biogas can be dangerous to people and the environment so it is beneficial to collect
the methane gas for safety and pollution control [1]. It used to just leak out into the
environment.
Current use in world and UK
World
 Landfill gas collection occurs in many places around the world. Historically, landfill gas has
often been flared (burned off) for safety and air pollution reasons.
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 It is increasingly being captured and used for energy.
 There are over 600 operational landfill gas energy projects in the United States.
 A range of countries have incentives in place to encourage using landfill gas for energy [1,3].
The landfill site has to have a ‘cap’
that will stop the gas from leaking
out everywhere. The gas is sucked
towards a perforated pipe and
collected for use.
Britain
 In the UK, around 20 terawatt-hours of landfill gas was collected in 2012.
 This is equivalent to around 2% of the natural gas used in the UK.
 The landfill gas was mainly used to generate electricity [2].
Climate change and impact on nature
 Methane (CH4), the major component of landfill gas, is also a powerful greenhouse gas
(GHG). It is at least 21 times more effective than CO2 at trapping heat in the atmosphere
over a 100-year time period.
 Methane is the second-most significant human produced GHG after CO2, accounting for 16%
of global GHG emissions.
 Preventing landfill gas escaping into the atmosphere and burning it for energy instead, helps
to reduce the increase in climate change [3].
 Greenhouse gas emissions are about
16 grams of CO2 or equivalent greenhouse gas per kilowatt-hour (gCO2e/kWh)
Risks
 The damaging impacts of landfill gas escaping from the ground are not just due to the climate
change impact.
 Landfill gas is not pure methane but includes small amounts of other gases, some of which
are smelly, poisonous and have carcinogenic trace components.
 Long-term exposure may have harmful health effects and it can damage vegetation.
 Landfill gas is potentially flammable, and explosive when concentrated in confined spaces.
 There is some risk in collecting and using landfill gas for energy, but there are greater risks in
not doing so [3].
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Cost now and in the future
 It is estimated that the benefits of collecting and burning landfill gas for energy can be up to
10 times the costs [3].
 It is highly beneficial for landfill gas to be captured and used for energy.
 Not all the benefits, such as reduced air pollution, will have a ‘cash value’.
Landfill gas is estimated to be a cheap way to generate electricity at around
6 pence per kilowatt-hour [4].
 The cost may increase in future if the amount of plant and animal waste in landfill decreases
with reductions in waste and increase in composting.
World and UK resource
World
 The world and UK resource for energy from landfill gas depends on the amount of waste
going into landfill, particularly plant and animal derived waste.
 The trend in Europe is for less waste to be sent to landfill - this has decreased by around a
third since the mid-1990s. More animal and plant waste is now composted.
Britain
 In the UK, both the total amount of waste generated and the amount sent to landfill are in
decline.
 The UK sent about 36% of its waste to landfill in 2012, down from 64% in 2005 [5]. If this
trend continues, the resource for landfill gas will go down over the coming decades.
Reliability/flexibility
 Landfill gas can provide a reliable and flexible way to generate heat and electricity.
 The bigger the gas store a system has, the more flexible it can be when it generates heat
and electricity.
 If landfill gas is cleaned of impurities it can be put into the gas grid and used in homes and
businesses [6].
 In the longer term a reliable supply of landfill gas may not be available as the amount of plant
and animal waste going to landfill declines.
 Landfill gas could be replaced by biogas that is deliberately produced, for example, by
anaerobic digestion of plant and animal waste.
Wales
 Burning landfill gas currently contributes 45.5 MW to Wales’s electricity producing capacity
[8]
 All councils in Wales now collect food waste separately and this service is available to 90%
of the Welsh population. It can then be composted or digested anaerobically. [9]
 http://www.wasteawarenesswales.org.uk/howisitrecycled#.VUepEpPSGwg short film clip
 http://www.biogen.co.uk/About-Us/Biogen-in-Wales/ Information
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 Since 2005/2006, Welsh councils have
reduced the amount of biodegradable
municipal waste sent to landfill by 59%. [10]
The site at Bryn Pica in Llwydcoed,
Aberdare, generates 1.8 MW of
electricity by burning landfill gas. [7]
Landfill gas vent Nantmel
References
[1] EIA (2013). Biomass Explained: Landfill Gas and Biogas. United States Energy Information Administration.
http://www.eia.gov/energyexplained/index.cfm?page=biomass_biogas [accessed 21/2/2014].
[2] DECC (2013). Statistics at DECC. Department for Energy and Climate Change.
https://www.gov.uk/government/organisations/department-of-energy-climate-change/about/statistics
[accessed 8/1/2014].
[3] IEA (2009). Turning a Liability into an Asset: the Importance of Policy in Fostering Landfill Gas Use
Worldwide. International Energy Agency.
http://www.iea.org/publications/freepublications/publication/landfill.pdf [accessed 21/2/2014].
[4] DECC (2012). Electricity Generation Costs. Department for Energy and Climate Change.
https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/65713/6883-electricitygeneration-costs.pdf [accessed 9/1/2014].
[5] Eurostat (2011). Municipal waste statistics. Eurostat.
http://epp.eurostat.ec.europa.eu/statistics_explained/index.php/Municipal_waste_statistics [accessed
21/2/2014].
[6] http://en.wikipedia.org/wiki/Landfill_gas_utilization [accessed 21/2/2014].
[7] http://www.amgen-cymru.com/facilities_gas.php
Biogen (2014) Biogen in Wales. Available at: http://www.biogen.co.uk/biogen-wales.asp [Accessed 10 Nov
2014]
[8] Department of Energy and Climate Change, 2014b).
[9] http://www.wasteawarenesswales.org.uk/howisitrecycled
[10] http://www.waste-management-world.com/articles/2014/09/wales-exceeds-biowaste-landfill-diversiontargets-by-23.html
– background information for Energy Trumps cards. Full resource available as free download at
http://learning.cat.org.uk/en/resources
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