tag:theconversation.com,2011:/au/topics/bio-methane-13664/articlesBio-methane – The Conversation2017-08-23T19:21:43Ztag:theconversation.com,2011:article/826442017-08-23T19:21:43Z2017-08-23T19:21:43ZCapturing the true wealth of Australia’s waste<figure><img src="https://images.theconversation.com/files/183101/original/file-20170823-13308-ce4edu.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">Methane is produced in landfill when organic waste decomposes. </span> <span class="attribution"><span class="source">Shutterstock</span></span></figcaption></figure><p>One of the byproducts of landfill is “landfill gas”, a mixture of mostly methane and carbon dioxide generated by decomposing organic material. Methane is a particularly potent greenhouse gas, but it can be captured from landfill and used to generate clean electricity.</p>
<p>Methane capture is a valuable source of power but, more importantly, it can significantly reduce Australia’s methane emissions. However the opportunity to produce energy from waste is largely being squandered, as up to 80% of the potential methane in waste is not used. </p>
<p>If more councils were prepared to invest in better facilities, Australians would benefit from less waste in landfill and more energy in our grids. Even the by-product from using state-of-art processing methods can be used as a bio-fertiliser.</p>
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<a href="https://theconversation.com/explainer-how-much-landfill-does-australia-have-78404">Explainer: how much landfill does Australia have?</a>
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<p>And while these facilities are initially more expensive, Australians are generally very willing to recycle, compost and take advantage of community schemes to reduce waste. It’s reasonable to assume that a considerable percentage of our population would support updating landfill plants to reduce methane emissions. </p>
<h2>Recycling in Australia</h2>
<p>Australia may have a bad rap when it comes to waste recycling, but there are plenty of positives.</p>
<p>Australians produce approximately <a href="https://data.oecd.org/waste/municipal-waste.htm">600 kilograms of domestic waste per person, per year</a> – no more than most northern European countries, which set the benchmark in sustainable waste management. </p>
<p>Looking at kerbside bins we, on average, <a href="https://www.ehp.qld.gov.au/waste/state-of-waste-report.html">recycle 30-35% of that waste</a>, saving much of our paper, glass, aluminium and steel from landfill (which also saves and reduces emissions). </p>
<p>Although the household recycling rate in Australia is less than the best-performing EU recycling rates of 40-45%, this is primarily due to a lack of access to (or awareness of) <a href="https://theconversation.com/does-not-compute-australia-is-still-miles-behind-in-recycling-electronic-products-63381">schemes to recycle e-waste and metals</a>. Data therefore suggests that at the community level, there is a willingness to minimise and recycle waste.</p>
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<p><strong><em>Read more:</em></strong></p>
<p><strong><em><a href="https://theconversation.com/does-not-compute-australia-is-still-miles-behind-in-recycling-electronic-products-63381">Australia is still miles behind in recycling electronic products</a></em></strong></p>
<p><strong><em><a href="https://theconversation.com/campaigns-urging-us-to-care-more-about-food-waste-miss-the-point-80197">Campaigns urging us to ‘care more’ about food waste miss the point</a></em></strong></p>
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<p>Between 55% and 60% of kerbside waste sent to landfill in Australia is organic material. Over 65% of this organic fraction is <a href="http://www.environment.gov.au/protection/national-waste-policy/national-waste-reports/national-waste-report-2013">food waste</a>, similar to the make-up of the EU organic waste stream, comprised of <a href="http://www.iea-biogas.net">68% of food waste</a>. </p>
<p>Despite this large fraction, approximately half of the household organic we produce – mostly garden waste – is <a href="https://www.ehp.qld.gov.au/waste/state-of-waste-report.html">separately collected and disposed</a>, again demonstrating high participation by the community in recycling when collection and disposal options are available. </p>
<h2>Turning waste into energy</h2>
<p><a href="https://theconversation.com/explainer-why-we-should-be-turning-waste-into-fuel-77463">Energy recovery from waste</a> is the conversion of non-recyclable material into useable heat, electricity, or fuel. Solid inorganic waste can be converted to energy by combustion, but organic waste like kitchen and and garden refuse has too much moisture to be treated this way. </p>
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<a href="https://theconversation.com/explainer-why-we-should-be-turning-waste-into-fuel-77463">Explainer: why we should be turning waste into fuel</a>
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<p>Instead, when organic waste is sent to landfill it is broken down naturally by microorganisms. This process releases methane, a greenhouse gas <a href="https://www.epa.gov/ghgemissions/overview-greenhouse-gases#methane">25 times more potent than carbon dioxide</a>. </p>
<p>Around 130 landfills in Australia are <a href="https://theconversation.com/explainer-how-much-landfill-does-australia-have-78404">capturing methane</a> and using it to generate electricity. Based on installed power generation capacity and the amount of waste received, Australia’s largest landfills use 20-30% of the potential methane in waste for electricity generation. </p>
<p>Ravenhall in Melbourne processes 1.4 million tonnes of waste per year, and proposes to generate <a href="https://www.mwrrg.vic.gov.au/assets/Uploads/Cleanaway-submission.pdf,%20_https://www.planning.vic.gov.au/__data/assets/pdf_file/0026/68057/Melbourne-Regional-Landfill-Expansion,-Ravenhall-Panel-Report.pdf">8.8 megawatts (MW) of electricity by 2020</a>. Roughly 461,000 tonnes of waste goes to Woodlawn in NSW, and <a href="http://www.veolia.com/sites/g/files/dvc1131/f/assets/documents/2016/10/2012_Environmental_Audit_Report_Golder_Associates.pdf">in 2011 it generated 4MW of electrical power</a>. Swanbank in Queensland receives 500,000 tonnes a year and generates 1.1MW. </p>
<p>The remainder of the methane is flared due to poor gas quality or insufficient transmission infrastructure, is oxidised as it migrates towards the surface of the landfill, or simply escapes. The methane generating capacity of waste is also diminished because organics begin composting as soon as they reach landfill.</p>
<p>But there are more efficient ways to capture methane using specialised anaerobic digestion tanks. The process is simple: an anaerobic (oxygen free) tank is filled with organic waste, which is broken down by bacteria to produce biogas. This is similar to the natural process that occurs in landfill, but is much more controlled and efficient in a tank.</p>
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Read more:
<a href="https://theconversation.com/biogas-smells-like-a-solution-to-our-energy-and-waste-problems-36136">Biogas: smells like a solution to our energy and waste problems</a>
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<p>The <a href="https://theconversation.com/biogas-smells-like-a-solution-to-our-energy-and-waste-problems-36136">biogas</a> can be combusted to produce electricity and heat, or can be converted to pure biomethane to be used either in the mains gas grid, or as a renewable transport fuel. In contrast to landfills, <a href="http://www.eubia.org/cms/wiki-biomass/anaerobic-digestion/">60-80% of the methane potential of waste</a> is used to generate electricity in anaerobic digesters, with most of the remainder used to power waste handling and the digestion process. </p>
<p>The nutrient-rich sludge that remains after anaerobic digestion, called digestate, is also a valuable <a href="http://task37.ieabioenergy.com/files/daten-redaktion/download/publi-task37/Digestate_Brochure_Revised_12-2010.pdf">biofertiliser</a>. It can support food production, and further reduce greenhouse gases by decreasing our reliance on energy-intensive manufactured fertilisers. </p>
<p>The use of food waste as a feedstock for anaerobic digestion is largely untapped in Australia but has huge potential. A site in Sydney’s geographic centre (<a href="https://earthpower.com.au/">Earth Power Technologies</a>) and <a href="https://arena.gov.au/assets/2015/11/Jandakot-Bioenergy-Plant.pdf">Richgro’s</a> Jandakot facility near Perth are part of a handful that are converting food waste to energy using this technology.</p>
<h2>The future of organic recycling</h2>
<p>Local council recycling and waste infrastructure is typically not a priority election issue, except for those close to existing or proposed landfills. </p>
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<a href="https://theconversation.com/australian-recycling-plants-have-no-incentive-to-improve-81336">Australian recycling plants have no incentive to improve</a>
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<p>Ratepayers are generally not informed of the possibility of separately collecting food waste, either for industrial-scale composting or methane capture. We have the right to this information, with costs and benefits presented in the context of the costs we already pay for waste management, and relative to the environmental performance of landfill.</p>
<p>As an example, landfill operators often promote the number of homes they power by electricity generated from methane as a key measure of sustainability. But how does this compare to the electricity and heat that might be obtained from an anaerobic digester that processes the same waste? </p>
<p>Given the choice, the Australian community may have an appetite to extend organic recycling beyond well-established garden waste composting. They only have to be asked.</p><img src="https://counter.theconversation.com/content/82644/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>William Clarke has received funding from the Australian Research Council, the Queensland Government and Remondis Australia. He is a member of the Managing Board of the International Waste Working Group.</span></em></p><p class="fine-print"><em><span>Bernadette McCabe is a member of Bioenergy Australia and is National Team Leader for the International Energy Agency Task 37 Energy from Biogas</span></em></p>Landfills produce huge amounts of methane. Many of the bigger operators capture it to turn into energy, but they’re wasting about 80% of what’s available. It’s time Australia stepped up.William Clarke, Professor of waste management, The University of QueenslandBernadette McCabe, Associate Professor and Principal Scientist, University of Southern QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/361362015-01-13T19:29:43Z2015-01-13T19:29:43ZBiogas: smells like a solution to our energy and waste problems<figure><img src="https://images.theconversation.com/files/68788/original/image-20150113-23795-uzyxie.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=496&fit=clip" /><figcaption><span class="caption">The Western Treatment Plant in Werribee, Victoria, largely powers itself using biogas – a by-product of sewage treatment. </span> <span class="attribution"><a class="source" href="http://www.shutterstock.com/cat.mhtml?searchterm=western%20treatment%20plant&language=en&lang=en&search_source=&safesearch=1&version=llv1&media_type=&page=1&inline=198966998">Jason Patrick Ross/Shutterstock</a></span></figcaption></figure><p>Could what we flush down the toilet be used to power our homes? Thanks to biogas technology, Australia’s relationship with organic waste – human and animal excreta, plant scraps and food-processing waste – is changing, turning waste into a commercial source of renewable energy. </p>
<p>A recent <a href="http://secure.environment.gov.au/wastepolicy/consultation/submissions/pubs/006-zerowasteaustralia.pdf">report </a> suggests that Australia produces about 20 million tonnes of organic waste per year from domestic and industrial sources. This in turn accounts for a large portion of national greenhouse gas emissions. <a href="http://australianpork.com.au/wp-content/uploads/2013/10/Fact-Sheet-Manure-Management.pdf">Manure from livestock industries</a> alone accounts for 22 Mt of carbon dioxide equivalents.</p>
<p>Organic waste, when broken down by bacteria, produces a methane-rich “biogas” that can be used to generate electricity and heat.</p>
<p>According to <a href="http://ecogeneration.com.au/news/can_australia_afford_to_waste_its_organic_waste/081439/">one estimate</a>, if all the organic waste from Australian domestic, industrial and agricultural industries was treated in biogas plants, it would have the potential to produce around 650 megawatts of electricity. That’s enough to power almost one million Australian homes.</p>
<h2>How it works</h2>
<p>Getting the process right can be tricky but the science is simple: fill an airtight tank known as an anaerobic (oxygen-free) digester with slurry made from biological waste, then let the bacteria get to work to produce a methane-rich gas that can be used to generate electricity and heat.</p>
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<img alt="" src="https://images.theconversation.com/files/68791/original/image-20150113-23804-pf90ni.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/68791/original/image-20150113-23804-pf90ni.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=450&fit=crop&dpr=1 600w, https://images.theconversation.com/files/68791/original/image-20150113-23804-pf90ni.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=450&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/68791/original/image-20150113-23804-pf90ni.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=450&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/68791/original/image-20150113-23804-pf90ni.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=566&fit=crop&dpr=1 754w, https://images.theconversation.com/files/68791/original/image-20150113-23804-pf90ni.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=566&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/68791/original/image-20150113-23804-pf90ni.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=566&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">Nope, it’s not a giant golf ball. This container in Scotland is storing biogas, ready for energy production.</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/greenerleith/5028920897">Greener Leith</a>, <a class="license" href="http://creativecommons.org/licenses/by-nc/4.0/">CC BY-NC</a></span>
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<p>Use what you need to power your pumps, motors and circuitry, and sell the rest back to the grid so that in as little as five years you recoup what you’ve outlaid on your biogas plant.</p>
<p>Renewable energy provided <a href="http://www.cleanenergycouncil.org.au/policy-advocacy/reports/clean-energy-australia-report.html">14.8%</a> of Australian electricity generation during 2013. Bioenergy totalled 7% of this, with biogas contributing to about 2.0% of the share of total renewable electricity capacity. In comparison, wind stands at 26% while solar power is 11%. The bioenergy industry expects biogas could be more important than solar, and as important as wind. The remainder of Australian bioenergy comes mostly from the combustion of sugarcane waste, also known as bagasse.</p>
<p>The majority of biogas plants in Australia – upwards of 50 – are associated with municipal waste treatment facilities. Commercial operations include <a href="http://www.melbournewater.com.au/whatwedo/Liveability-and-environment/energy/Pages/Energy-efficiencies-and-renewable-sources.aspx">Melbourne Water</a> and <a href="https://www.sydneywater.com.au/Publications/Reports/AnnualReport/2009/performance/optimising_resources.html">Sydney Water</a>, which use sewage as their biogas feedstock.</p>
<h2>Low-cost options emerge</h2>
<p>The slow uptake of the technology, particularly in the intensive livestock industries, has been due to the difficult financial environment, policy uncertainty and grid connectivity. </p>
<p>Covered anaerobic lagoons, sometimes called ponds, are the preferred type of digester for Australian agricultural industries – they are a low-cost option which performs well under our warmer conditions with minimal maintenance.</p>
<p>The technology has attracted a lot of attention in the pork industry over the past 10 or so years with <a href="http://infohouse.p2ric.org/ref/03/02635.htm">Berrybank</a> near Ballarat and <a href="http://blantyrefarms.com.au/quality-sustainability">Blantyre Farms</a> at Young using piggery waste as their major feedstock. </p>
<p>Abattoirs, dairies and poultry farms are also investing in biogas technology as they look for a means of solving their waste and odour problems as well as reducing their carbon footprints, not to mention their electricity and natural gas bills.</p>
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<span class="caption">A biogas plant in Austria.</span>
<span class="attribution"><a class="source" href="http://www.rohkraft.net/en/">rohkraft.net</a></span>
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<p>The uptake of this technology has produced significant energy savings and environmental improvements for red-meat processing plants such as the <a href="http://www.beefcentral.com/processing/jbs-biogaswater-project-wins-award-for-environmental-innovation/">JBS Dinmore</a> facility and the <a href="http://www.abc.net.au/news/2014-08-26/rendering-plant-energy-savings/5686688">AJ Bush Beaudesert</a> rendering plant, both located in South-East Queensland.</p>
<p>The recent installation of covered anaerobic lagoons by <a href="http://www.beefcentral.com/processing/environment-processing-waste-water-moves-from-problem-to-profit/">Oakey Beef Exports</a> and <a href="http://www.cleanenergyfinancecorp.com.au/media/63281/20130731-cefc-pdf-factsheet-darlingdownsfresheggs_lr.pdf">Darling Downs Fresh Eggs</a> demonstrates the huge potential to adopt biogas technology in one of Australia’s key livestock-producing and food-processing regions. </p>
<h2>ARENA puts Australia in global talks</h2>
<p>Interest in using biological feedstock including manure has encouraged the Federal Government’s <a href="http://arena.gov.au/">Australian Renewable Energy Agency</a> (ARENA) to fund Australia’s involvement in the International Energy Association’s (IEA) Bioenergy Task 37: Energy from Biogas.</p>
<p>This funding, secured through the industry-funded body <a href="http://www.bioenergyaustralia.org/">Bioenergy Australia</a>, means Australia can sit at a table of global representatives to look at what is going right and what is going wrong in biogas production systems around the world.</p>
<p>Part of Bioenergy Australia’s involvement in Task 37 is to look at which Australian industries are hurting the most through waste disposal problems and huge power bills, and where it is feasible for biogas to turn that around.</p>
<p>If we get it right, biogas could be making a significant contribution to Australia’s Renewable Energy Target (RET) to deliver a 20% share for renewables in Australia’s electricity mix in 2020.</p>
<p>Bioenergy Australia’s aim is less concrete: that by 2020, bioenergy will be recognised and widely adopted as a sustainable resource in Australia.</p><img src="https://counter.theconversation.com/content/36136/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Bernadette McCabe receives funding from Meat and Livestock Australia (MLA) and Australian Meat Processor Corporation (AMPC). She is a member of Bioenergy Australia and is Australia's National Team Leader for the International Energy Agency's (IEA) Bioenergy Task 37: Energy from Biogas.</span></em></p>Could what we flush down the toilet be used to power our homes? Thanks to biogas technology, Australia’s relationship with organic waste – human and animal excreta, plant scraps and food-processing waste…Bernadette McCabe, Associate Professor and Vice Chancellor's Senior Research Fellow, University of Southern QueenslandLicensed as Creative Commons – attribution, no derivatives.tag:theconversation.com,2011:article/346152014-11-25T06:23:31Z2014-11-25T06:23:31ZBeyond the ‘poo bus’: the many uses of human waste<p>A British “<a href="http://www.bbc.co.uk/news/uk-england-bristol-30115137">poo bus</a>” went into service last week, powered by biomethane energy derived from human waste at a sewage plant. </p>
<p>For those of us who follow these matters – and my academic works include <a href="http://phg.sagepub.com/content/early/2011/02/12/0309132510394704">Geographies of Shit: Spatial and temporal variations in attitudes towards human waste</a> – this was an exciting moment, a rare piece of good PR for human waste. After all, most societies strongly associate it with a sense of disgust. Poo threatens the health of around 2.5 billion people … and it smells bad. </p>
<p>Yet it also represents an important resource, used in lots of different ways throughout history. Though the “poo bus” has captured the imagination there are many other uses for human waste.</p>
<h2>Farmer’s friend</h2>
<p>Urine is particularly versatile. In Medieval Europe, it was widely used to clean clothes while the Romans used it for tanning leather and cleaning wool. </p>
<p>It also makes an excellent agricultural fertiliser. Before the 19th century realisation that human waste was a health risk, sewage was routinely transported from British towns to villages for use as manure. </p>
<p>However, most of the health risks can be eliminated if urine (harmless if unpleasant) and feces (full of diseases) are separated at source through some form of <a href="https://theconversation.com/why-not-change-the-way-you-wee-to-save-the-world-31317">urine diversion toilet</a>. Such strategies make sound environmental and economic sense given the urine produced annually by each adult contains enough plant nutrients <a href="http://www.ecosanres.org/pdf_files/Ecological_Sanitation.pdf">to grow 250kg of grain</a>, enough to feed them for a year.</p>
<p>China has a long history of using such toilets to collect urine for use as a fertiliser. In some regions of Sweden these toilets are now mandatory, improving environmental quality as well as creating significant savings on fertiliser costs for farmers. </p>
<h2>Poo power</h2>
<p>Although harvesting biogas from human waste is not a new concept (Assyrians were using it to warm their bath water back in the <a href="http://www.adelaide.edu.au/biogas/history/">10th century BC</a>), the potential to simultaneously manage waste and generate power has attracted increasing attention in recent decades.</p>
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<img alt="" src="https://images.theconversation.com/files/65381/original/image-20141124-8334-8lgtx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&fit=clip" srcset="https://images.theconversation.com/files/65381/original/image-20141124-8334-8lgtx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=600&h=398&fit=crop&dpr=1 600w, https://images.theconversation.com/files/65381/original/image-20141124-8334-8lgtx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=600&h=398&fit=crop&dpr=2 1200w, https://images.theconversation.com/files/65381/original/image-20141124-8334-8lgtx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=600&h=398&fit=crop&dpr=3 1800w, https://images.theconversation.com/files/65381/original/image-20141124-8334-8lgtx.jpg?ixlib=rb-1.1.0&q=45&auto=format&w=754&h=501&fit=crop&dpr=1 754w, https://images.theconversation.com/files/65381/original/image-20141124-8334-8lgtx.jpg?ixlib=rb-1.1.0&q=30&auto=format&w=754&h=501&fit=crop&dpr=2 1508w, https://images.theconversation.com/files/65381/original/image-20141124-8334-8lgtx.jpg?ixlib=rb-1.1.0&q=15&auto=format&w=754&h=501&fit=crop&dpr=3 2262w" sizes="(min-width: 1466px) 754px, (max-width: 599px) 100vw, (min-width: 600px) 600px, 237px">
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<span class="caption">What to do with all this sludge?</span>
<span class="attribution"><a class="source" href="https://www.flickr.com/photos/gtzecosan/6305610332">SusAnA</a>, <a class="license" href="http://creativecommons.org/licenses/by/4.0/">CC BY</a></span>
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<p>Modern waste treatment leaves behind sewage sludge that has traditionally been difficult to dispose of. However when the sludge is fed into a large vat, essentially like a stomach, and left to digest (an anaerobic digestion plant) it can produce valuable biogas and nutrient-rich digestate. </p>
<p>Biogas can be used directly as a fuel, cleaned up to create bio-methane or fed through a combined heat and power unit to generate electricity. The digestate can be used as a fertiliser or soil conditioner, helping in the process to reduce methane emissions, enhance plant growth and sequester carbon through photosynthesis.</p>
<p>In rural China especially, low-tech biogas sanitation systems play an important role in killing pathogens while providing clean cooking fuel and fertiliser from the digestate. </p>
<p><a href="http://www.cardiff.ac.uk/archi/programmes/cost8/case/watersewerage/bromma.html">Sweden</a> and Germany are particularly big anaerobic digestion users. In Germany, sewage plants can sell their excess energy back to the national grid. Attractive tariffs designed to promote renewable energy have even meant many plants have started to “feed” their anaerobic digestion units with purpose-grown energy. </p>
<p>Though the UK’s biogas industry lags behind that of countries like Sweden and Germany, some sewage works are already releasing biogas into the national grid. With each adult producing around 30kg of dried sewage each year, there is lots of growth potential. If all of the UK’s sewage plants adopted this technology, <a href="http://www.bbc.co.uk/news/uk-11433162">around 350,000 homes</a> could be supplied with gas derived from human waste.</p>
<h2>Toilet-fuelled transport</h2>
<p>The environmental benefits of poo-powered travel are clear: bio-methane produces 95% less CO<sub>2</sub> and 80% less nitrous oxide than diesel as well as having no particulate emissions. In the UK, there is enough bio-methane to fuel half the country’s large trucks. </p>
<p>Four years ago engineers developed a <a href="http://www.telegraph.co.uk/motoring/news/7929191/Bio-Bug-Car-run-on-human-waste-is-launched.html">VW Beetle fuelled by bio-methane gas</a> generated at the Avonmouth sewage plant near Bristol. This same sewage plant is now powering the “poo bus” and it could do even more. Avonmouth produces around 17m cubic meters of bio-methane each year which, if exported to the grid, could meet the gas needs of 8,300 homes. </p>
<p>But Sweden, again, is a leader here. Their transport policy has prioritised the development of bio-methane for trucks and buses; an initiative that has helped to clean up the air and <a href="http://www.publications.parliament.uk/pa/cm201012/cmselect/cmenvaud/1024/1024vw05.htm">meet renewable energy targets</a>. </p>
<p>At a smaller and more experimental scale, meanwhile, researchers at the Bristol Robotics Laboratory have succeeded in <a href="http://info.uwe.ac.uk/news/uwenews/news.aspx?id=2598">charging a mobile phone</a> using electricity generated from urine. Using a microbial fuel stack, they have succeeded in taking advantage of the metabolism of live micro-organisms to create electricity from convert organic matter – in this case urine. </p>
<p>Other research teams working on similar “<a href="http://www.industrytap.com/using-urine-to-power-a-cell-phone-soon-well-all-be-doing-it/16512">pee conversion</a>” technologies have succeeded in generating <a href="http://www.theguardian.com/environment/2011/mar/09/pee-power-fuel-hydrogen-urine">electricity, clean water and hydrogen</a> from human waste. </p>
<p>If such technologies can be made to work on a bigger scale, the future for renewable power looks not only bright … but yellow.</p><img src="https://counter.theconversation.com/content/34615/count.gif" alt="The Conversation" width="1" height="1" />
<p class="fine-print"><em><span>Sarah Jewitt does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.</span></em></p>A British “poo bus” went into service last week, powered by biomethane energy derived from human waste at a sewage plant. For those of us who follow these matters – and my academic works include Geographies…Sarah Jewitt, Associate Professor of Geography, University of NottinghamLicensed as Creative Commons – attribution, no derivatives.