UK biomass: an overview

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1 EI Data Service useful information: DSI19 Biomass Factsheet Industrial processes I Biofuels I Heating I Facts and figures I Further information Updated September 2011 UK biomass: an overview Biomass, containing energy that living plants capture by the process of photosynthesis, is the use of plant and animal material as a source of fuel. Biomass energy can come from three main energy sources: wood (often as a waste product from the pulp, paper and paperboard industries), waste (agricultural, municipal, manufacturing and landfill gas) and alcohol fuels (mainly derived from corn). In order to use energy that is stored in green plants and other organic matter, biomass facilities burn wood, agricultural wastes and/or methane gases from landfills or anaerobic digesters to spin a turbine and generate electricity. Using biomass in this way helps reduce the amount of material that goes into landfills, and can help reduce the amount of greenhouse gas that would otherwise be released into the atmosphere. There are a number of legislative incentives which are likely to lead to a greater use of biomass use in the UK. In April 2002 the UK Renewables Obligation (RO) came into effect; this is an obligation on all electricity suppliers to supply a specific proportion of electricity from eligible renewable sources, such as active solar heating, photovoltaics, onshore and offshore wind power, wave power, large and small scale hydro, biomass or geothermal aquifers. The proportion required for each supplier was 10.4% for April 2010 March 2011, rising to 15.4% by 2015/16; however a Banding Review is being carried out in 2011, with yet-to-be announced new rates to take effect from In 2007 the EU also set a target for 20% of energy consumed across Europe to come from renewable sources by Different EU countries have taken on different individual targets, based on existing renewable capacity and relative GDP per capita; the UK needs to meet a legally binding target of 15%. The UK Renewable Energy Strategy, published in 2009, is the Department of Energy & Climate Change s action plan for achieving the UK's 15% share of the EU 2020 renewable energy target. Their analysis indicates that a significant 30% of the overall 15% renewable energy target could come from biomass heat and power, rising to around 50% if biofuels for transport are included. The 27 million BBSRC Sustainable Bioenergy Centre was launched in February 2009 with the intention of producing research on the development of advanced bioenergy and biofuels. Industrial processes Combined heat and power (CHP) plants are an efficient way to generate electricity if a use for the surplus heat can be found. Conventional electricity power stations discard waste heat in their cooling towers, meaning around 70% of the energy used to produce electricity is wasted. CHP plants capture this heat for supply to homes, businesses and industry. In its simplest form, the CHP plant employs a gas turbine, an engine or a steam turbine to drive an alternator, resulting in electricity. Although most UK plants are powered by natural gas, an increasing number use liquid, solid or gas by-products, waste products or biomass fuels such as straw bales or waste wood pellets. A small CHP plant is typically 2 MWe and a large station 30 MWe. At end December 2010 the installed capacity of UK large-scale >10MWe CHP schemes (using various fuels, 6% of which were renewable) was 5,614 MWe producing 26 TWh annually, just under 7% of UK electricity production. Co-firing of biomass with coal in large-scale coal fired electricity generation plants has been encouraged in the UK. Power plant operators receive Renewable Obligation Certificates (ROCs) for the portion of their output that is biomass fuelled. This economic incentive has been successful and many coal plants are currently co-firing. There is currently no cap on co-firing with energy crops, but to reduce the risk of flooding the ROC market with co-fired ROCs, there is a limit of 12.5% on the number of ROCs using non-energy crop biomass a supplier can use to meet their obligation. 1

2 Gasification of biomass can be carried out to produce pipeline quality biomethane. The National Grid is currently investigating the potential of Hydrogen Enriched Natural Gas (HENG), a process by which carbon is extracted from methane to leave hydrogen, which can be injected back into the gas supply stream. Estimates have been made that up to 50% of UK residential gas demand could be met with renewable gas produced from materials such as sewage/waste water, manure, straw, food waste, biodegradable waste, wood waste and Miscanthus, an energy crop suitable for growing in the UK. Anaerobic digestion is a microbiological process that converts high moisture content organic wastes such as animal manure, food processing residues and sewage sludge into a methane rich biogas typically around 65% methane and 35% carbon dioxide. The methane can be used as a fuel for electric generation. Anaerobic digestion is the method by which landfill gas is generated. Biomass uses Biofuels Liquid biofuels can be used to power transport vehicles. The two most common biofuels used in the UK are bioethanol, which can be blended into petrol, and biodiesel, which can be blended into diesel. Biodiesel can be made from oily plants, animal fat, or used vegetable oil. Bioethanol is petrol quality liquid fuel consisting of ethanol produced from biomass. Unlike petrol and diesel, biofuels contain oxygen so adding biofuels to petroleum products allows the fuel to combust more completely. When burnt it produces fewer emissions than petroleum-based diesel and can be used in existing diesel engines without any modifications. Ethanol (a type of alcohol) is produced from sugar-rich crops such as corn and sugar beet. The sugar is extracted from the plants and allowed to ferment, producing ethanol. Ethanol is used widely in Brazil where it is mixed with petrol 80-90% petrol and 10-20% ethanol. Such mixes are also often used in the USA, especially in cities that suffer from air pollution such as Los Angeles. The presence of just a small amount of ethanol makes the fuel burn more cleanly. The availability of biodiesel and ethanol-petrol mixes is increasing in the UK following the introduction of the Renewable Transport Fuel Obligation Programme (RTFO). From April 2008 the RTFO has placed an obligation on fuel suppliers to ensure that an increasing proportion of their UK overall fuel sales is made up of fuel from a renewable source, rising to 5% (by volume) by 2013/2014. To help meet this target a network of bio-refineries that convert wheat and other crops into bioethanol is being developed in the UK, at sites in Teeside, Immingham, Corby, Grimsby and Hull. Much research is also being carried out into potential new non food-based biofuel crops. Algae has great potential as a biofuel, as it can be grown on seawater or wastewater as well as unproductive non-arable land, eliminating the need to divert arable land from the production of food crops. Given favourable conditions some species double in size every day and therefore could provide an oil yield per hectare 5-10 times that of any conventional energy crop. However, the technology to convert algae into usable fuel on a large scale is still at least a decade away. Another crop being investigated is the Jatropha tree, for its oily seeds. Native to South America, the Jatropha tree can survive in dry, arid land which is unsuitable for crop growing, but unfortunately it grows far more productively on higher quality land with more rainfall or irrigation. By using renewable energy fuels for 10% of our transport fuel mix the UK could reduce oil consumption by 2.5 million tonnes of oil equivalent (3% of our oil demand) by This would help reduce the need to import oil, reduce the impact of crude oil supply disruptions and alleviate the impact on petrol and diesel retail price of spikes in the price of crude oil and petroleum products. However, there are increasing concerns over the potential for heavily subsidised biofuels to displace existing food crops, leading to an increase in food prices worldwide. While biofuels can make a substantial contribution to our transport fuel needs, in the short-to-medium term they are likely to be part of the solution rather than the whole answer. 2

3 Heating Over 80% of the fuel delivered to public buildings is used for heating, so heating represents a significant opportunity for savings in greenhouse gases. Biomass heating systems can be used for heating of buildings, hot water production, steam production, or any combination of these. They can be used at almost any scale, from domestic (c.10kwth) through to light commercial (c.50kwth to several MWth), to industrial or district heating systems (up to hundreds of MWth). Fuels used in biomass heating systems include wood chips, pellets and logs. Wood chips or pellets made from waste wood are currently used to provide hot water and heating in a range of public and private sector buildings such as schools and offices. District heating, where a single boiler installation is used to provide heat to a number of buildings, is common in some European countries and has been used in a number of UK residential projects. There are two main ways to use wood for heating: a standalone wood stove burning logs or pellets to heat a single room or a boiler burning pellets, logs or chips connected to a central heating and hot water system. Standalone stoves Costs for a domestic standalone pellet stove are around 4,300 including installation, while a standalone log stove will usually cost less than half that amount. (Energy Saving Trust, 2011). Boilers Biomass boilers tend to be physically larger and more expensive compared to gas or oil fired boilers. Additional costs can arise from the civil engineering works associated with the construction of silos and much larger boilerhouses, and the boilers and fuel feed systems themselves are considerably more expensive. The requirement for a buffer vessel also adds cost. Typically, a complete biomass boiler system will cost up to ten times that of a gas or oil fired boiler system (Biomass Energy Centre FAQs, v1.0). A small automatically fed pellet boiler for an average home costs around 11,500 including installation (Energy Saving Trust, 2011) while the Carbon Trust estimate a typical figure of 200,000 for an industrial biomass heating system (Carbon Trust, Biomass heating: A practical guide for potential users, 2009). Woodchip fired heating systems of less than 500kW cost between per output kw, but for systems over 500kW, capital costs fall to per kw. Biomass boilers are usually serviced annually by the company which installed them; service costs depend on the parts required and the plant type and are likely to have a labour cost in the range of 400-1,000/year for plants larger than 1 MWth. The price of woodchips usually varies from p per kwh, costing from per tonne depending on the moisture content, the source of the wood and the distance it has to travel. The much greater capital cost of biomass systems means that the payback period will, inevitably, be longer than for a fossil fuelled boiler system. Set against the greater capital cost is the usually lower price of biomass fuels. The majority of biomass systems to date have been installed in areas where mains gas is not available and where, in comparison to the price of fuel oils, biomass fuels are relatively cheap. Taking into account these two factors a typical payback period for a biomass boiler is about 8 years, but this figure can vary considerably. If fuel oil prices continue to increase steadily over the coming years, payback periods will fall as wood prices are not anticipated to increase at the same rate as fossil fuel prices. Finally, where grants or other incentives are available a typical payback period is about 5 years. (Biomass Energy Centre FAQs, v1.0). The Carbon Trust has estimated that four key biomass fuels in the UK (forestry crops, dry agricultural residue, waste wood and woody energy crops) have the potential to supply about 1.5% of the UK s energy supply. The Carbon Trust, Biomass Sector Review (2005) 3

4 Biomass facts and figures During 2010 in the UK a total of 11,915 GWh electricity was generated from biomass, of which 5,037 GWh was from landfill gas, 2,506 GWh from co-firing with fossil fuels, 1,594 GWh from municipal solid waste combustion, 1,406 GWh from plant biomass, 702 GWh from sewage sludge digestion and 670 GWh from animal biomass. (Source: Department of Energy & Climate Change, Digest of UK Energy Statistics, 2011) Of the total 25,734 GWh generated from renewable electricity in the UK during 2010, 46% came from the combined biomass sources of landfill gas, sewage gas, domestic & industrial wood, co-firing, waste combusion, animal & plant biomass and liquid biofuels. Landfill gas accounted for two-fifths of the biomass generation. (Source: Digest of UK Energy Statistics, 2011) In 2010 the UK had 2,096.6 MWe installed capacity of biomass and wastes (Source: Digest of UK Energy Statistics, 2011) In % of gross electricity consumption was produced from renewable sources in the EU-27, of which 3.0% came from biomass. The EU 2010 objective requires that 21% of gross electricity consumption in the EU should come from renewable sources by (Source: European Commission, EU energy and transport in figures: Statistical pocketbook 2010) In ,808 GWh was generated from biomass in the EU % of the total electricity generated by renewables. The largest share of the renewable electricity generated came from hydro power (59.0%). (Source: EU energy and transport in figures: Statistical pocketbook 2010) In the US during 2010 just over 8% of total US energy consumption was derived from renewables, of which biomass contributed 53% (Source: US Energy Information Administration) Biofuels facts and figures An estimated 175 million litres of biodiesel and 287 million litres of bioethanol were produced in the UK in Meanwhile, HM Revenue and Customs (HMRC) figures show that 1,045 million litres of biodiesel and 631 million litres of bioethanol were consumed in To make up the shortfall in UK supply, around 870 million litres of biodiesel were imported in 2010, after continuing adverse market conditions caused a number of significant producers to go out of business in 2009 or operate plants at reduced output. (Source: Digest of UK Energy Statistics, 2011) In 2009/ % of the UK s total road transport fuel supply was biofuel, slightly over the target of 3.25% required by the RTFO Order and a significant increase on the 2.7% supplied in 2008/09. Biofuel was supplied from at least 31 countries, and at least 17 different feedstocks. A disappointing 31% of the biofuel used met the Renewable Fuel Agency s Qualifying Environmental Standard; the rest came from unknown sources or sources not verified as sustainably sourced. (Renewable Fuels Agency, Year Two of the RTFO, 2011) It has been estimated that by 2030 biofuels manufactured from algae could replace at least 6% of worldwide road transport biodiesel or at least 12% of aviation jet fuel. (Source: Department of Energy and Climate Change, Renewable Energy Strategy, 2009) During 2008 in the EU total biodiesel consumption was 791,1302 tonnes of oil equivalent (toe) and bioethanol consumption 176,5959 toe, with Germany and France leading in consumption (Source: Europe s Energy Portal) The US government projects US consumption of all liquid fuels to increase by 0.5% annually from 2009 to 2035, with 54% of the increase accounted for by biofuels, including biodiesel blended into diesel, motor fuel containing up to 85 percent ethanol (E85), and ethanol blended into motor gasoline. (Source: Energy Information Administration, Annual Energy Outlook 2011, with Projections to 2035) 4

5 Further information Useful websites Anaerobic Digestion portal aiming to provide information on AD to a wide audience ranging from the public to professionals The BIOMASS Energy Centre - gives an overview of biomass, its pros and cons; the technology involved; links to the organisations conducting research into biofuels in the UK; legislation and other practicalities concerning its use; relevant news stories and forthcoming events. The Renewable Energy Centre - a useful overview of the biomass industry in the UK and a directory of the companies and organisations involved. This includes the use of biomass as solid fuels as well as biodiesel, bioethanol and biogas Theoretical Ethanol Yield calculator US Department of Energy calculator, calculates the theoretical ethanol yield of a biomass feedstock Biomass organisations/government departments Department for Energy & Climate Change - information about the current state of energy from biomass in the UK; impact on the community; public opinion and grants, schemes and subsidies. Department for Transport In October 2010 the government announced that the DfT will take over the former role of the Renewable Fuels Agency (RFA) as the UK s independent sustainable fuels regulator. Biofuels will now be managed in a new "Low Carbon Fuels" team at the DfT.The RFA will be abolished by 31 March 2011 via a Statutory Instrument (SI) to be tabled in Parliament. IEA Biotechnology - an organisation set up in 1978 by the International Energy Agency (IEA) with the aim of improving cooperation and information exchange between countries that have national programmes in bioenergy research, development and deployment. The US Department of Energy - Office of Energy Efficiency and Renewable Energy's Biomass Program US Energy Information Administration - official US energy statistics for biomass Biomass/renewable energy publications The Carbon Trust, Biomass heating: Technology fact sheet (2010) free download from website via login The Carbon Trust, Biomass heating: A practical guide for potential users (2009) free download from website via login The Carbon Trust, Biomass Sector Review (2005) free download from website via login Department of Energy and Climate Change (DECC), Renewable Energy Strategy (2009) The Institution of Civil Engineers (ICE), Briefing Sheet on Biomass (2010) - one of a series of up-to-date status reports from the ICE Energy Board, outlining the technology and the current issues facing the biomass industry. 5