epuk scotland biomass guidance nov 2010

7/28/2019 EPUK Scotland Biomass Guidance Nov 2010

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Biomass andAir Quality Guidance

for Scottish Local Authorities


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About Environmental Protection UK

Environmental Protection UKs vision is of a cleaner, quieter, healthier world.

We seek changes in policy and practice to minimise air, noise and land

pollution, bringing together stakeholders to inform debate and inuencedecision making. We are a national membership based charity and have been

playing a leading role in environmental protection in the UK since 1898.

Original material for this guidance document has been supplied by:

AEA Technology London Borough of Camden Environmental Protection UK

Parts of this guidance have drawn upon other documents, including material prepared by:

The Carbon Trust Beacons Low Emission Strategy Group

Environmental Protection UKEnvironmental Protection UK Scotland gratefully acknowledges the assistance provided by the steering group setup to oversee the development of this guidance. Steering group member organisations included:

AEA Technology BMT Cordah Dundee City Council Scottish Environment Protection Agency The Scottish Government

The steering group was chaired by BMT Cordah.

Funding for the development of this guidance was provided by DEFRA under the Air Quality Grant Programme.

Image on front page: Salvez Dodds

Environmental Protection UK, June 2010

Credits

Contact Details:

Environmental Protection UK - Scotlandc/o Glasgow City Council231 George Street,GLASGOW, G1 1RX

Tel 0141 287 6530Fax 0141 287 6592Email [email protected] Charity in Scotland: SCO40990Registered Charity in England and Wales: 221026


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Contents

Executive Summary

Chapter 1 Background

Scope of this Guidance ....................................................................................................................... 1

Types of Biomass ................................................................................................................................ 1 Introduction to the Air Quality Impacts of Biomass Plant..................................................................... 2

The Policy Context .............................................................................................................................. 3

The Policy Context (Air Quality) .......................................................................................................... 6

Chapter 1 - Reading Links................................................................................................................... 7

Chapter 2 Boilers, Fuels, Standards and Certications

Biomass Boilers ................................................................................................................................... 9

Biomass (Wood) Fuels ...................................................................................................................... 10

Emission Standards and Certication ................................................................................................11

EN Standards ................................................................................................................................11 UK Emission Standards ............................................................................................................... 12

Other National Regulations .......................................................................................................... 12

Ecolabelling and Other Emission Controls ................................................................................... 13

Chapter 2 - Reading Links................................................................................................................. 13

Chapter 3 Approvals and Consents

Biomass in the Planning System ....................................................................................................... 15

General Permitted Development ....................................................................................................... 15

Section 75 Agreements ..................................................................................................................... 15

Regulation of Biomass Plant ............................................................................................................. 16 Regulatory Regimes .......................................................................................................................... 16

Pollution Prevention and Control ................................................................................................. 16

Best Available Techniques ........................................................................................................... 16

Waste Incineration Directive ........................................................................................................ 17

The Large Combustion Plant Directive (LCPD) ........................................................................... 17

The Clean Air Act ......................................................................................................................... 18

Smoke from Chimneys ................................................................................................................. 18

Emissions from Commercial Premises ........................................................................................ 19

Approval of Chimney (Stack and Flue) Heights ........................................................................... 19

Powers to Request Monitoring and Information ........................................................................... 19

Chapter 3 - Reading Links ................................................................................................................. 20

Planning ....................................................................................................................................... 20

Regulation .................................................................................................................................... 20

Chapter 4 Assessing Potential Impacts

Energy Statements and Basic Information about a Biomass Boiler .................................................. 23

Material Considerations at Planning.................................................................................................. 26

Technical Information to Obtain on a Biomass Boiler / CHP System ................................................ 26

Screening Assessment LAQM Technical Guidance Nomographs .................................................. 26 Dispersion Modelling and Stack Height Assessment ........................................................................ 28



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Contents

Chapter 5 Assessing Cumulative Impacts

Logging Information........................................................................................................................... 31

Conducting Screening Assessments ................................................................................................. 31

Transboundary Assessments ............................................................................................................ 31

Monitoring Uptake of Smaller (Single House) Biomass Systems...................................................... 31


Chapter 6 Mitigating Potential Impacts

Abatement of Nitrogen Oxides .......................................................................................................... 34

Abatement of Particulate Matter ........................................................................................................ 34

Automatic Heat Exchange Cleaning.................................................................................................. 35

Abatement Efciencies and Costs..................................................................................................... 35

Fan Assisted Dispersion .................................................................................................................... 35

Design Optimisation .......................................................................................................................... 36

Mitigation Through Wider Measures ................................................................................................. 36


Chapter 7 Anticipated Progress

The Renewable Heat Incentive ......................................................................................................... 37

Emissions Standards......................................................................................................................... 37

Maintenance Requirements .............................................................................................................. 37

Research and Modelling.................................................................................................................... 37


Appendix A Biomass Boiler Technologies

Batch Fuelled Appliances .................................................................................................................. 40

Continuously Fired Boilers ................................................................................................................ 40 Pellet Boilers ..................................................................................................................................... 41

Wood Log Boilers .............................................................................................................................. 41

Continuous Firing of Woodchips ....................................................................................................... 41

Factors Inuencing Boiler Efciency ................................................................................................. 42

Combined Heat and Power ............................................................................................................... 43

Appendix B Fuel Specication

Introduction ........................................................................................................................................ 44

An Overview of the Effects of Fuel Specication on Operational and Emissions Performance ........ 44

Biomass Fuel Types .......................................................................................................................... 44 Specic Characteristics of Wood Fuels ............................................................................................. 44

Standards for Biomass Fuels ............................................................................................................ 44

References ........................................................................................................................................ 45

Appendix C Screening Models

.......................................................................................................................................................... 54

Appendix D The Air Quality Standards for Scotland

UK Objectives Not Included in Regulations....................................................................................... 56

Downloadable Tools

Biomass Unit Conversion and Screening Assessment Tool

Template Boiler Information Request Form

Template Boiler Information Log


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Executive Summary

In common with other combustion appliances, emissions from biomass boilers and biomass combined

heat and power systems should be managed to ensure potential air quality impacts are controlled.

Management of combustion appliances can include product and fuel standards, emissions abatement

equipment, regulatory controls and / or planning controls to restrict where certain appliances can be

installed. This guidance aims to help local authorities understand and manage emissions from biomass

combustion, with a focus on the most common biomass fuel wood.

Biomass fuels are currently being encouraged to help Scotland meet ambitious targets under the

Climate Change (Scotland) Act and the related Renewables Action Plan. Unabated climate change

presents a major environmental and health hazard to the whole world, and de-carbonising our energy

supply is therefore a priority. At the same time the UK is currently failing to meet legally binding EU air

quality standards in many areas, including parts of Scotland, and public health is suffering as a result.

Management of biomass combustion should therefore seek to encourage biomass use, whilst limiting any

negative effect on, or indeed improving, air quality.

As a general rule of thumb biomass boilers fuelled by clean, new wood have lower pollutant emissions

than coal, roughly equivalent emissions to oil, but higher emissions than equivalent gas red boilers. The

process of assessment should therefore follow a risk-based approach based upon:

The location of the boiler, e.g. could it affect areas of poor air quality?

Is it in a densely populated area?

Whether the biomass plant is substituting for a boiler using a different fuel; i.e. if its substituting

for oil or coal, emissions might actually drop, but if it is replacing a gas red system they are likely

to rise

The likely emissions standard of the boiler

The type, quality and quantity of biomass fuel used.

The approach to assessment should therefore have a lighter touch where risk is low (for example in a

rural area where air quality is good, and coal and oil are the realistic alternative fuels), and more rigorous

where risk is high (for example in or adjacent to an Air Quality Management Area).

The declared view of the Scottish Government is that the air quality impacts of a major expansion in

biomass heat can be controlled through the use of high quality, low emission plant and targeting rural

areas off the gas grid where coal and oil red plant are currently used. In urban areas, or where an Air

Quality Management Area has been declared, they would expect biomass heat deployment to be less

common, and larger (and therefore cleaner) biomass units to be more prevalent.

This guidance document contains information on the policy background to biomass, climate change and

air quality, details of the technology used in biomass plant and their regulation, and nally advice on the

management and mitigation of biomass emissions. Several tools have been developed alongside this

guidance to help local authorities and their partners manage emissions. These are listed on the contents

page, and are also available for download from www.environmental-protection.org.uk/biomass.

This guidance does not intend to be a complete guide to biomass, and suggested reading links have

been placed in the text if more detailed information is needed about any of the policies, technologies and

methodologies raised. This guidance is intended as a companion to the more general Environmental

Protection UK planning guidance Development Control Planning for Air Quality which was updated inApril 2010. Environmental Protection UK will be launching Air Quality and Climate Change integrated

guidance towards the end of 2010.

Executive Summary


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Biomass and Air Quality Guidance


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Background

Chapter 1 - Background

1.1 Biomass burning is perhaps the oldestmethod of providing heating and hot water.In recent years pressure to reduce our

reliance on fossil fuels such as coal, oil andgas has encouraged a large expansion inthe use of biomass heat. Concerns havebeen raised that this may have an adverseeffect on air quality and public health,particularly in densely populated urbanareas.

1.2 Biomass can have a variety of meanings,but in the context of this guidance it refersto deriving energy from biological materialthrough a transformation process. Theenergy provided may be heat, electricity ormechanical power. The biological materialmay come from animal or plant sources(including animal wastes and composts),whilst the transformative process maybe direct combustion or perhaps involvegasication, fermentation or pyrolysis.

1.3 The status of biomass as a renewablelow carbon fuel means there is growinginterest in using it to help meet local andnational targets for renewable energy.As a relatively mature renewable energy

technology, biomass can be one of themost cost effective and therefore attractivetechnologies to use.

Scope of this Guidance

1.4 This guidance covers the burning of dryand seasoned woody fuels only as this isthe most popular form of biomass deployedin the UK (e.g. wood chips, pellets andlogs with up to 50% moisture content).The document is aimed at Scottish local

authorities and is intended to help ofcersand elected members with strategic planningand decisions on individual planningapplications. This guidance relates togood practice and the legislative positionin Scotland; a version of this guidance forEngland and Wales is also available on theEnvironmental Protection UK website.

1.5 The guidance focuses on assessing andmanaging the effects of biomass on airquality specically nitrogen dioxide (NO

2)

and particulates (PM10

and PM2.5

). It doesnot cover other pollutants in depth. Lifecyclecarbon dioxide (CO

2) emissions from

different biomass fuels are beyond the scopeof this guidance. The Environment Agency

report Biomass Carbon Sink or CarbonSinner? can provide further information onthis subject (see Chapter 1 reading links).

1.6 Biomass does have other environmentaland sustainability impacts associated with its

use. These are mentioned in this guidanceand links are given to sources of furtherinformation. Dry, woody fuels are mostcommonly burnt in a boiler to produce heatfor space heating and / or hot water or ina Combined Heat and Power (CHP) unitto produce both heat and electricity. Thisguidance uses the term biomass boilers tocover both boilers and CHP units.

1.7 The burning of waste wood may be subjectto more stringent environmental regulation

than the burning of clean, new wood. Theseissues are examined in Chapter 3.

1.8 At the time of writing this document,technology and legislation surroundingthe air quality effects of biomasswere developing quickly. Updates tothis guidance will be posted at www.environmental-protection.org.uk/biomassand we strongly recommend checking forupdates when using this guidance.

1.9 Where biomass plants occur as part of a

larger development there will be a need tomeet regulatory (pollution) conditions andalso gain planning approval. Both issuesare looked at in Chapter 3 of this guidance.Wider air quality issues surroundingdevelopment control are considered in theguidance document Development Control:Planning for Air Quality which is available todownload from the Environmental ProtectionUK website.

1.10 An information leaet for developers hasbeen produced alongside this guidance

document. This leaet explains the issuessurrounding biomass and air quality, theinformation that local authorities mayneed to assess the air quality impacts of aproposed biomass boiler and the reasonswhy they may request this information.

Types of Biomass

1.11 There is a wide range of biomass fuelswhich can be broadly described in terms ofwet and dry sources. Under these two

broad headings they can be grouped intove sub-categories (Table 1.1).

Table 1.1: Original sources of biomass fuels


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Introduction to the Air Quality Impacts

of Biomass Plant

1.12 In common with other combustionprocesses, the combustion of biomass forenergy can affect air quality in a varietyof ways. Emission levels of pollutantssuch as particulates (PM), polyaromatichydrocarbons (PAHs) and carbon monoxide(CO) depend on the completeness of thecombustion process. The temperaturesin conventional biomass combustion areconsidered to be not sufciently high enoughto oxidise atmospheric nitrogen and oxidesare almost exclusively formed from fuel

nitrogen (note that this may not be the casefor newer biomass technologies such asgasication that have higher combustiontemperatures). Emission levels of NO

xare

therefore heavily dependent on the chemical

composition of individual fuels (as are theemissions of SO

x). Overall emissions will

therefore be dependent on:

The specication and design of thecombustion plant,

The chemical and physical qualities of thefuel (fuel quality)

The presence of any emissions abatementtted to the plant

1.13 In many cases the introduction of newbiomass combustion plant will displaceheat and / or power that would otherwisehave been provided by other combustionappliances. The relative contributionwill depend on the type of fuel(s) and

combustion technology displaced. Forexample, whilst the sulphur and nitrogencontent of wood biomass is low it ishigher than that of gas and hence thereplacement of gas red stoves may leadto a modest increase in SO

2and NO

x

emissions. Conversely, displacement offuels such as coal may lead to an overallreduction in emissions. Table 5.5 of thedocument Review of Greenhouse GasLife Cycle Emissions, Air Pollution Impactsand Economics of Biomass Production

and Consumption in Scotland provides asimplied explanation of this (see Chapter 1Reading Links).

1.14 Planning applications proposing theinstallation of a biomass boiler should beaccompanied with an air quality assessment,the complexity of which should follow a risk-based and staged approach. Key questionsto consider when making an initial broadassessment should include:

Geography what is the planned locationof the biomass boiler? Is it near denselypopulated areas and could it potentiallynegatively affect any areas of poor airquality? Is it near sensitive receptors suchas children, especially if installed in schools?

Topography is the location in a built-uparea?

Fuel substitution / alternatives will thebiomass boiler be displacing a boiler runningon a different fuel and if so, what fuel? If the

development containing the boiler is on anew site, what other fuels might be available(and what would be their comparative effecton air quality)?

Virgin wood Dry includes roundwood,harvesting residues (brash),

bark, sawdust, crowns, needlesand residues of tree surgery

Energycrops

Dry includes woody energycrops (short rotation forestry,willow, eucalyptus, poplar),grassy energy crops (miscanthusand hemp), sugar crops (sugarbeet), starch crops (wheat,barley, maize/corn), oil crops(rape, linseed, sunower), andeven hydroponics (lake weed,

kelp, algae)

Agriculturalresidues

Wet includes pig and cattleslurry, sheep manure, grasssilage

Dry poultry litter, wheat orbarley straw, corn stover

Foodresidues

Wet includes wastes fromvarious processes in thedistillery, dairy, meat, sh, oils,fruit and vegetables sectors

Industrialresidues

Wet includes sewage sludge

Dry includes residues fromsawmills, construction, furnituremanufacturing, chipboardindustries, pallets

Table 1.1:

Original Sources of Biomass Fuels


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Background

widespread with increased temperatures,sea level rises and a greater frequency ofextreme weather events having seriouseffects on the natural environment as well ason human health and wellbeing. Biomass,when used appropriately, can reduceemissions through the displacement of fossilfuels and can contribute towards carbonabatement.

1.19 In 2008 the Department for Environment,Food and Rural Affairs (DEFRA)commissioned a biomass impact studyto help inform the development of the UKRenewable Energy Strategy, the results ofwhich were communicated to EnvironmentalProtection UK in a letter from DEFRA andDECC Minister Lord Hunt of Kings Heath in

May 2009. The study modelled the potentialair quality impacts of a large increase inbiomass heat (installed capacities of 38TWhand 50TWh, total heat demand in 2005 was844TWh).

1.20 In May 2009 the Minister for Environment,Roseanna Cunningham MSP, sent a letterto all local authority Chief Executives whichclaried the Scottish Governments positionon biomass and how Scotland will meetits target of 20% of energy produced from

renewable sources by 2020. The Ministerre-iterated this message whilst addressingdelegates at Environmental ProtectionUK Scotlands event in November 2009.Results of DEFRAs analysis and theMinisters key message are shown in Box1.2.

1.21 Implementation of the Ministers keymessage has implications for local planningand strategic policy, however some of theimportant technical requirements (e.g.product emission standards) are not yet

in place. Many of the issues raised arecovered in this guidance including currenttechnologies, standards and certication(Chapter 2), risk based approachesto assessment (Chapter 4), assessingcumulative impacts (Chapter 5) andabatement technologies (Chapter 6).Chapter 7 looks at some of the anticipateddevelopments that will help implement thetargeted approach outlined by the Ministerand updates to this guidance will be postedas new information becomes available.

1.22 The Climate Change (Scotland) Act2009 commits the Scottish Governmentto achieving an 80% cut in CO

2emissions

What is the likely emissions performance ofthe boiler?

What type of biomass fuel will the boiler berunning on?

1.15 The use of biomass can also causenuisances most commonly dust, smoke andodour. Emission of smoke in smoke controlareas is likely to be an offence under theClean Air Act. Problems outside smokecontrol areas can either be addressedthrough nuisance legislation or the CleanAir Act provisions prohibiting the emissionof dark smoke. Odour is most likely to beassociated with a combination of inadequatecombustion and poor plume dispersion orfrom fuel storage.

1.16 Indirect air quality effects will also arisefrom increased biomass use. For example,emissions associated with transportingbiomass fuel to the site (e.g. vehicle, railor ship emissions) and the potential forincreased nitrous oxide (N

2O) emissions (a

potent greenhouse gas associated with agreater use of fertilisers in the increasingproduction of biomass fuels).

The Policy Context

1.17 Policies to encourage the use of biomasshave primarily been driven by climatechange, the need to reduce greenhousegases (GHGs) and renewables targets (20%of Scotlands total energy use by 2020).Other relevant drivers include sustainability,energy security and rural employment. UKlegislative drivers have developed withinthe framework of EU and other internationalpolicies, strategies and instruments suchas the Kyoto Protocol to the United Nations

Framework Convention on Climate Change(UNFCCC).

1.18 CO2

in the atmosphere is understood tohave a warming effect. Since pre-industrialtimes the level of atmospheric CO

2has

increased from about 280 parts per millionto 380 parts per million largely due toemission from the combustion of fossil fuelsand human induced land use changes.Observations have shown that the worldis now warming as a result and modellingpredicts that if we continue to emit CO

2

and other GHGs at present rates therewill be a signicant change in climate overthe coming decades. The consequencesof unabated climate change would be


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(from 1990 levels) by 2050. The Actalso sets an interim target of at least a42% reduction in emissions by 2020 andestablishes a framework of annual targets.

1.23 The Scottish Governments Renewables

Action Plan is updated every 6 months andwas last published in July 2010 (see Chapter1 Reading Links for the latest version).Under the Climate Change (Scotland) Actthere is also a statutory obligation to publisha separate, more detailed RenewablesHeat Action Plan. This was published inNovember 2009 and outlines Scotlandscommitment to 11% of heat demand fromrenewable sources by 2020.

Results of the Impact Assessment where certainconditions are met impacts can be reduced to amanageable level, and that no additional breaches of thecurrent EU air quality directives air quality limit valuesawould occur. These conditions are:

That all new biomass plant are of high qualityb,corresponding to the best performing units currentlyon the market;

That the majority of biomass heat uptake replaces

or displaces existing coal and oil red heating; That the majority of uptake is located off the gas

grid and therefore away from densely populatedurban areas;

That levels of uptake where the local authorityhas declared an Air Quality Management Areaunder Section 83 of the Environment Act 1995 aresubstantially lower than other areas.

As conditions move away from this scenario, themodelled adverse / negative impacts on air quality andpublic health increase signicantly.

Current Levels of Biomass in the UK Biomass usein the UK is currently at a very low level; to achieve 7% of

the UK heat market, the level of biomass use in the UK

would have to increase 20 fold The fact that the market

penetration of biomass is very low is an advantage here

rather than a drawback: by setting the right conditions now

we can ensure almost all of the eventual installed capacity

is of a high standard, and in locations unlikely to have air

quality issues meaning that early installations will not

result in exceeding air quality limits.

Box 1.2: Results from DEFRA Biomass Impacts Assessment and Ministers Key Message

The Ministers Key Messages for Local Planning

Policies In the development of local planningpolicy and the consideration of development planningapplications, the evidence points toward the following keypoints:

To meet the 2020 targets for renewable energy, theUK needs to increase very substantially the amountof renewable heat generated, and biomass heat isone of the key technologies;

The potential conicts between these goals andair quality can be avoided through the use of highquality, low emission plant. The replacement ofold coal and oil red plant with high quality woodred plant located off the gas grid and away fromdensely populated urban areas may actuallybenet air quality. In urban areas or where an AirQuality Management Area has been declared,we would expect biomass heat deployment to beless common and larger (and therefore cleaner)biomass units to be more prevalent.

Encouraging the use of larger plant, for example inconjunction with the development of heat networks,

will result in a system where air quality emissionsare easier to control than from a larger number ofsmall plant.

a: The Scottish LAQM annual mean standard forPM

10is more stringent than the EU Air Quality

Directives PM10

air quality limit

b: The outcome of the DEFRA impact study wasbased on high quality biomass emissions of 20g/GJPM

10and 50g/GJ NO

2

1.24 European Renewable Energy Targets the EU has adopted a target of 12%renewable energy in the EU by 2010 andhas produced a range of implementationmeasures. These include Directives withtargets for renewable use in electricitygeneration and transport fuels and aBiomass Action Plan. Further to the 2010target, the EU has agreed a 20% renewableenergy target for 2020. This relates to allenergy consumed and thus for the rst timeincludes heat as well as electricity. Undera burden sharing agreement the UK hasagreed to a target of 15% of all energy tocome from renewable sources by 2020.


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Background

1.25 Current UK Policy The Climate ChangeAct 2008 commits the UK Government tothe same reduction in CO

2emission by 2050

as the Scottish Government. Under the2008 Act, the UK Government sets out aseries of ve year carbon budgets with threesuccessive budgets always in legislation.The rst three budgets were set in 2009,committing to cuts (from 1990 levels) of 22%by 2010, 28% by 2017 and 34% by 2022.

1.26 The UK Energy White Paper, released inMay 2007, has acknowledged the role ofbiomass and its potential contribution torenewable energy in the UK. This followsthe UK Governments Biomass Strategywhich acknowledges the role of biomassin helping to meet climate change and

renewable energy targets, and bringstogether the various government policiesthat encourage biomass. Whilst a UKdocument, it acknowledges that separatestrategies have been, or are being,developed to address the specic conditionsthat apply in Scotland, Wales and NorthernIreland. It does not include any bindingtargets; instead its main aims are to:

Realise a major expansion in the supply anduse of biomass in the UK.

Facilitate the development of a competitiveand sustainable market and supply chain.

Promote innovation and low-carbontechnology development so biomass candeliver relatively higher energy yields.

Contribute to overall environmental benetsand the health of ecosystems through theachievement of multiple benets from land

use.

1.27 Currently the main mechanism to encouragerenewable energy development is theRenewables Obligation (RO); boththe UK and Scottish Governments havemechanisms in place which support thegeneration of electricity from renewableresources through a system of RenewableObligation Certicates (ROCs). As of 2009,large biomass CHP systems will receivedouble ROCs (i.e. twice as many certicates

for every unit of energy generated) and anew feed-in tariff will provide benets forsmaller biomass CHP systems (up to 5MW).The UK Government has conrmed that the

Renewable Heat Incentive (RHI) will goahead.

1.28 The Scottish Governments RenewablesAction Plan identies collective actions bygovernment, its agencies and partners to

ensure at least 20% of Scotlands energycomes from renewables by 2020. Aroutemap for renewable heat and bioenergyare included in this plan. The routemapsare supplemented by a more detailedRenewable Heat Action Plan for Scotland(published November 2009) which sets outa framework for activity across a wide rangeof areas which will contribute to Scotlandmeeting its 2020 target.

1.29 Planning and biomass Regional (Regional

Spatial Strategies) and local (LocalDevelopment Frameworks) plans must bedeveloped in accordance with Governmentplanning guidance (planning issues arelooked at in more depth in Chapter 3). Forbiomass, relevant guidance is provided by:

Renewable Energy PAN 45. SPP 6has recently been revoked and has beensubsumed by the new SPP (February 2010)

Pollution Control PAN 51.

1.30 Local Climate Change and RenewableEnergy Targets Many local authoritieshave developed renewable energy targetsfor new developments in their area. Thesebecame known as the Merton Rule after theLondon Borough of Merton which was therst local authority to introduce such targets.

1.31 The Scottish Government has set 15National Outcomes, several of which arerelevant for biomass, in particular:

We value and enjoy our built and naturalenvironment and protect it and enhance it forfuture generations.

We reduce the local and globalenvironmental impact of our consumptionand production.

1.32 Each Scottish local authority has nowagreed its Single Outcome Agreement(SOA) with the Scottish Government. SOAsset how local authorities will work towardsimproving outcomes for residents in away that reects local circumstances andpriorities within the context of the NationalOutcomes.


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1.33 Support and Funding Funding andsupport for the use and productionof biomass is available from manyorganisations and schemes, including:

The Scottish Biomass Heat Scheme

The Scottish Rural Development Programme

Regional Biomass Advice Network

The Community and Renewable EnergyScheme (CARES)

Enhanced Capital Allowances

EU funding for research, demonstration andIntelligent Energy Europe, which may fundinformation dissemination and study tours

Low Carbon Buildings Programme (closedfor new applications in May following changein UK Government)

The Carbon Emission Reduction Target (forenergy supply companies)

The Carbon Trust

Energy Saving Scotland Home Renewables

Community Renewables toolkit

The Policy Context (Air Quality)

1.34 The House of Commons EnvironmentalAudit Committee reported in March2010 that poor air quality reduces thelife expectancy of everyone in the UKby an average of seven to eight monthsand up to 50,000 people each yearmay die prematurely because of it. Airpollution also causes signicant damageto ecosystems (see Chapter 1 ReadingLinks). Consequently, policies to reduceconcentrations of pollutants in the air are

aimed at countering the negative effectsof air pollutants. Air quality standards arestill failing to be met in many parts of theUK, particularly in densely populated urbanareas.

1.35 The most widespread air quality problemsrelate to contribution from particulate matter(PM), nitrogen dioxide (NO

2) and ozone (O

3),

with PM being the pollutant most stronglyassociated with biomass combustions.Particulates are referred to as PM

10or PM

2.5

with the number denoting their maximumsize in micrometers. The smaller particles(PM

2.5) are understood to have the greatest

effect on human health. PM and NO2

are strongly associated with combustionprocesses; vehicles normally being the mostsignicant source of both. O

3is a product of

polluted air reacting in strong sunlight; as along-lived pollutant it can often build up tosignicant concentrations well away fromthe urban areas where the pollutants areemitted.

1.36 Developments in air pollution policy duringthe 1990s resulted in the UK Governmentintroducing the rst National Air QualityStrategy in 1997 as a requirement of theEnvironment Act 1995. A series of nationalair quality standards and objectives wasalso introduced. The Act also establishedLocal Air Quality Management (LAQM)as a way to address localised hot spots of

poor air quality which could not be resolvedeffectively through national policy measures.Following devolution, a revised Air QualityStrategy for England, Scotland, Wales andNorthern Ireland was published in 2000 withan addendum issued in 2003.

1.37 Since the development of the rst AirQuality Strategy legally binding standardsfor several air pollutants have been set ata European level, including standards forPM

10, PM

2.5and NO

2. These EU standards

have been incorporated into revisions ofthe UK Air Quality objectives and Air QualityStrategy, the most recent revision havingtaken place in 2007 (note that objectivesfor PM

2.5are not as yet incorporated in the

LAQM regime). Details of the current airquality standards are presented in AppendixD.

1.38 The 2007 revision introduced a target valueand exposure reduction target for PM

2.5,

the former to be achieved by 2020. Theexposure reduction target calls for a 15%

cut in urban background exposure between2010 and 2020. Urban areas are denedas agglomerations with a population over100,000.

1.39 The Scottish Government has introducedtighter PM

10and PM

2.5air quality objectives

than the rest of the UK. Whilst theseobjectives are not enforceable by theEuropean Commission, they are applicableto LAQM in Scotland.

1.40 In 2008 a new European Air QualityDirective came into force. This tidied upexisting legislation by merging severalDirectives into one, introduced standardsfor PM

2.5and provided member states


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Background

with a means of applying for complianceexibilities (deadline extensions) to addressbreaches of air quality standards. The UKhas applied for an extension to meet PM

10

standard and is in the process of doing sofor NO

2. The applications will need to be

accompanied by a robust plan for achievingthe standards by the new deadlines.

1.41 The LAQM regime requires individual localauthorities to periodically assess air qualityand identify locations within their boundarywhere the air quality objectives may beexceeded by their target dates. Whereany such exceedences are predicted, andwhere there is relevant public exposure,local authorities have a duty to declare AirQuality Management Areas (AQMAs).

Such designations are a statutoryrequirement and UK local authorities havea duty to work towards achieving the airquality objectives based upon standards forseven key pollutants. The legislative basisfor LAQM in England, Scotland and Walesis the Environment Act 1995 and in NorthernIreland the Environment (Northern Ireland)Order 2002.

1.42 Following the designation of AQMAs, localauthorities are required to develop Air

Quality Action Plans (AQAPs) to identifyand implement actions to improve airquality locally. Such plans require effectivecollaboration between authority departmentsand external agencies and stakeholders(e.g. SEPA, Transport Scotland andindustry). Land-use planning and transportplanning underpin the development ofeffective AQAPs.

1.43 Local authorities have taken differentapproaches to establishing AQMAs.

Some have declared only the exact areaswhere exceedences are expected to takeplace; this often leads to the declarationof multiple AQMAs in, for example, a citycentre. Others have chosen to declare thewhole area around where exceedences arefound to form a single AQMA or even makea whole administrative area declaration(common in London). It should therefore benoted that air quality standards might not beexceeded across an entire AQMA.

1.44 Local authorities have been provided

with technical and policy guidance by theScottish Government to assist them withtheir duties under LAQM. The technicalguidance applies UK wide and was last

updated in 2009. The policy guidance wasalso updated in 2009 and only applies toScotland; there are separate documents forother UK administrations.

1.45 The Environment Act 1995 also forms the

legislative basis linking the actions of SEPA(the environmental regulator) and the AirQuality Strategy. The Act requires SEPAto have regard to the Air Quality Strategyin discharging pollution control functions.Broadly this means that regulators will basepermit conditions for applicable installationsupon Best Available Techniques (BAT). Thisis covered in more depth in Chapter 3.

Chapter 1 Reading Links

Environmental Protection UK BiomassGuidance Update Page

(http://www.environmental-protection.org.uk/biomass)

Environmental Protection UK PlanningGuidance

(http://www.environmental-protection.org.uk/assets/library/documents/8691_Air_Quality_Guidance_(nal_web).pdf)

The Scottish air quality website anddatabase

(http://www.scottishairquality.co.uk/)

The UK Air Quality Archive (UK Air Qualityportal)

(http://www.airquality.co.uk/)

Air Quality Strategy Objectives

(http://www.airquality.co.uk/standards.php)

Scottish Government LAQM Technical andPolicy Guidance

(http://www.scotland.gov.uk/Topics/Environment/waste-and-pollution/Pollution-1/16215/TG09)

(http://www.scotland.gov.uk/Topics/Environment/waste-and-pollution/Pollution-1/16215/6151)

Environment Agency Report Biomass carbon sink or carbon sinner?

(http://www.environment-agency.gov.uk/business/sectors/32595.aspx)


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The Scottish Governments RenewablesAction Plan

(http://www.scotland.gov.uk/Publications/2010/08/02141416/0)

The Scottish Governments RenewablesHeat Action Plan


The House of Commons EnvironmentalAudit Committee report on air quality

(http://www.publications.parliament.uk/pa/cm200910/cmselect/cmenvaud/229/22902.htm)

Scottish Governments Review ofGreenhouse Gas Life Cycle Emissions,Air Pollution Impacts and Economics ofBiomass Production and Consumption inScotland report


DECC Annual Energy Review

(http://www.decc.gov.uk/assets/decc/

What%20we%20do/UK%20UK%20energy%20supply/237-annual-energy-statement-2010.pdf)



15/639.

Boilers, Fuels, Standards and Certications

Chapter 2 Boilers, Fuels,

Standards and Certications

2.1 The performance of a biomass boiler willdepend heavily upon the design of the boiler

and the type of fuel used. The relationshipbetween the boiler and the fuel is crucial boilers are usually designed to burn aspecic fuel type and quality. Deviation fromthis fuel specication without adjustments tothe boiler set up can lead to poor efciencyand increased emissions of air pollutants.

2.2 Current UK and EU wide emission standardsfor biomass boilers are largely inadequateas tools for setting demanding air qualityconditions, as they mostly do not directly

cover emissions for NOx, PM2.5 and PM10.

2.3 Emission standards and eco-labels havebeen developed in other European countriesand may be quoted in the informationprovided to local authorities. Thesestandards are however difcult to apply tothe UK due to a wide range of approachesused for testing cycles and emissionsmeasurement. Whilst emission standardsprovide some general indication of howpolluting an appliance may be, compliance

with emission standards cannot guaranteethat breaches of the LAQM air qualitystandards will be avoided.

2.4 This chapter provides a brief overview ofboilers, fuels, standards and certication.More detailed information on boilers andfuels can be found in Appendices A and B aswell as the Carbon Trust document Biomassheating: a practical guide for potential users.

Biomass Boilers

2.5 Biomass appliances usually fall into twocategories batch fuelled or continuouslyred. Batch fuelled appliances are usuallysmall (


16/6310.


2.8 More detailed information on biomassappliances and their operation is availablein Appendix A and in the Carbon Trustdocument Biomass heating: a practicalguide for potential users.

Biomass (Wood) Fuels

2.9 Wood fuels are available in a variety ofdifferent formats and qualities. The mostcommon formats for wood fuels are shownin Table 2.2.

2.10 Wood fuels will also vary in their

characteristics. A detailed list of woodfuel characteristics is listed in Appendix B,however they can generally be describedunder three headings:

Table 2.2: Common Wood Fuel Formats and

their Utilisation

Logs

Bales (of wood)

Pellets

Chipped/shredded

wood

Batch fuelled. Most commonlyused in small-scale systems(


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Emission Standards and Certication

EN Standards

2.14 Table 2.3 lists European EN standardsfor residential solid fuel appliances andfor independent boilers with nominal heatoutput up to 300kW. The Standards includeminimum requirements for efciency,construction and safety of appliances.No EN Standards include NO

xemission

performance criteria and only EN 303 Pt 5(the independent boiler Standard) includes

Table 2.3: Residential Solid Fuel Appliance EN Standards

Standard Harmonised Title

EN 303 Pt 5 No Heating boilers - Part 5: Heating boilers for solid fuels, handand automatically stocked, nominal heat output of up to300kW - Terminology, requirements, testing and marking.

EN 12809 Yes Residential independent boilers red by solid fuel - Nominalheat output up to 50kW - Requirements and test methods.

EN 12815 Yes Residential cookers red by solid fuel - Requirements and testmethods.

EN 13229 Yes Inset appliances including open res red by solid fuels -Requirements and test methods.

EN 13240 Yes Room heaters red by solid fuel - Requirements and testmethods.

EN 14785 Awaiting formalpublication

Residential space heating appliances red by wood pellets -Requirements and test methods.

EN 15250 Awaiting formalpublication

Slow heat release appliances red by solid fuel -Requirements and test methods.

prEN 15281(under development) Sauna stoves red by solid fuel - Requirements and testmethods.

prEN 15544(under development)

One off tiled / mortared stoves - Dimensioning.

PM emissions criteria. EN Standards forresidential appliances are harmonised andmandatory across the EU; EN 303 Pt 5however is not a harmonised Standard.

2.15 A harmonised Standard is a European

standard prepared by CEN/CENELEC undera mandate from the Commission with aview to fullling a requirement of a specicDirective (in the case of residential heatingappliances this is Directive 89/106/EEC theConstruction Products Directive).

2.16 Many of the heating appliances covered bythe EN Standards for residential appliancescan also include boilers in addition to theprimary heating (or cooling) function. EN

12809 includes boilers that also providea space-heating function. Boilers that donot provide a space-heating function arecovered by EN 303 Pt 5 which applies to

solid fuel boilers up to 300kW output. ThisStandard denes an efciency testingprocedure and also assigns performanceclasses based on efciency and emissions

of PM, CO and organic gaseous carbon(OGC) classes for Total PM emissions aresummarised in Table 2.4.


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2.17 Although EN 303 Pt 5 includes PM limitvalues it is not a harmonised Standardand the Standard indicates that nationalrequirements in several member states(including the UK) differ from the Standardin terms of PM measurement protocols andpermitted emissions.

2.18 In addition to the performance Standards,there is a draft EN Technical Specicationfor measurement of gaseous emissioncomponents. A draft EN TechnicalSpecication for particulate measurementshas not been agreed.

UK Emission Standards

2.19 Solid fuel furnaces up to 20MWth

(thermalinput) are generally regulated under theClean Air Act (CAA). For combustionappliances above 20MW

th, the Pollution

Prevention and Control Regulations (PPC)will apply. Appliances smaller than 20MW

th

can also fall under PPC, e.g. if they are

burning waste. Regulatory regimes arecovered in more detail in Chapter 3.

2.20 The CAA was introduced to control airpollution arising from widespread use of coaland includes provision for the creation ofSmoke Control Areas, general controls onsome emissions and emission limits (for gritand dust) for larger solid fuel combustioninstallations.

2.21 Within a smoke control area applianceseither must burn authorised smokelessfuels or the appliance needs to have beenassessed and exempted by the ScottishGovernment for use in some control areas(for further information see http://www.

Table 2.4: Summary of EN 303 Pt 5 Total PM Emission Classes

Stoking Nominal heat output

kW

Emission limit,

mg/m3 dry at STP (0C, 101.3kPa) and 10% O2

Class 1 Class 2 Class 3

Manual

Automatic

50 200 180 150

>50 to 150 200 180 150

>150 to 300 200 180 150

50 200 180 150

>50 to 150 200 180 150

>150 to 300 200 180 150

uksmokecontrolareas.co.uk). Emissionlimits for exempted appliances are detailedin BS PD 6434 covering residentialcombustion (smaller than about 44kWoutput). Emission limits for grit and dustare applied to larger appliances (greaterthan about 240kW output) irrespectiveof whether they are located in a SmokeControl Area. Assessment of emissionsfrom appliances greater than about 44kW forCAA exemption is generally by interpolationbetween the BS PD 6434 limits and the grit

and dust emission limits.2.22 If an activity falls under PPC then controls

on other pollutants (in addition to PM) canapply.

Other National Regulations

2.23 A number of countries apply emissioncontrols to biomass / wood combustionappliances. For residential appliances,these are generally applied under type

approval arrangements under which themanufacturer undertakes tests on anexample appliance to assess compliancewith emission limits (and EN productStandards). Table 2.5 provides a summaryof countries applying emission limit valuesfor biomass combustion.


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2.24 Several of these countries have emissionmeasurement Standards or protocols,however a range of approaches are adoptedwhich means that it can be difcult tocompare results between countries. Thedifferences in measurement procedureconcern test cycles (e.g. whether toinclude start-up emissions) and emissionmeasurement procedures. The differencesin measurement procedure also include

whether the procedure only looks at (i)lterable material or (ii) lterable andcondensable material also whethermeasurements are undertaken directlyon the chimney ue or through a dilutionchamber.

Ecolabelling and Other Emission Controls

2.25 There are a number of ecolabel andbiomass grant schemes in Europe thatspecify performance criteria that are

typically higher than the minimum efciencyrequirements of the EN product Standardsand national regulations. A number ofthese ecolabel schemes recognise the

Table 2.5: Countries Applying Emission Limits for Biomass Combustion

Country Emission limit value

(ELV)

Comment

NOx

PM

Austria X X ELVs applied to residential appliances and several sizeranges of larger boilers including 50-100kW, 100-350kW.Different NO

xELVs applied for different wood types.

Belgium X Proposed PM ELVs for residential appliances.

Denmark PM ELVs for roomheaters and


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5Table 2.6: Ecolabelling Criteria for Biomass Combustion

Ecolabel ELV Comment

NOx

PM

X X

Country

Blue Angel Germany Includes efciency and limit values for woodpellet stoves and wood pellet boilershttp://www.blauer-engel.de/en/index.php

Nordic Swan Sweden, Norway,Denmark & Finland

Includes efciency, PM and VOC limit valuesfor various residential roomheater types andNO

x, PM and VOC limits for boilers


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Approvals and Consents

Chapter 3


3.1 New biomass boilers will require regulatoryapproval and in many cases planningconsent too. The latter may be requiredfor a development as a whole in caseswhere the boiler is part of a new buildingdevelopment or, for new buildings, stacks,etc., where a biomass boiler is installed in anexisting development.

3.2 This chapter provides only a brief descriptionof biomass in the planning system andshould be read alongside the EnvironmentalProtection UK document DevelopmentControl: Planning for Air Quality. Another

source of guidance is the DEFRA documentLow Emission Strategies published as partof their LAQM guidance.

Biomass in the Planning System

3.3 In addition to meeting regulatoryrequirements, all but the smallest biomassinstallations will also require planningconsent. The basic planning process forrenewable energy is described on the BISwebsite (see reading links).

3.4 Biomass energy proposals >50MW fallwithin Schedule 2 of the EnvironmentalImpact Assessment (Scotland)

Regulations 1999 (the EIA Regulations)and are subject to an EnvironmentalImpact Assessment (EIA) if they areconsidered likely to have signicant effectson the environment. Any thermal biomasspower stations with a heat output of at least300MW would fall under Schedule 1 ofthe EIA Regulations meaning that an EIA

would be mandatory (this also includes allheat plant that co-re biomass and have anoutput >300MW).

3.5 The main planning legislation in Scotlandis the Town and Country Planning(Scotland) Act 1997. The Planning etc.(Scotland) Act 2006 amends the 1997Act; from August 2009 the bulk of the 2006Act is in force with regards to developmentplanning and development management(including appeals, local reviews and

enforcement).

General Permitted Development

3.6 Certain types of changes to propertiescan be made without the need to applyfor planning permission. These are calledpermitted development rights (PDR) and

derive from general planning permissiongranted by the Scottish Parliament and notthe local authority. In some areas of thecountry, known generally as designatedareas, PDR are more restricted. These mayinclude inter alia conservation areas andWorld Heritage Sites.

3.7 Local planning authorities can remove PDRby issuing an Article 4 direction. Article 4directions are made when the character ofan area of acknowledged importance would

be threatened and they are most common inconservation areas. Planning departmentscan provide details of the status of permitteddevelopment in a local authority area. PDRtend to focus upon the visual impact of adevelopment and it is imperative that airquality is not overlooked when consideringsuch applications.

3.8 When a biomass boiler or CHP unit isinstalled in an existing property planningpermission is not normally needed ifall of the work is internal. Under theTown and Country Planning (General

Permitted Development) (Domestic

Microgeneration) (Scotland) Amendment

Order 2009 if the installation requires anexternal ue it will normally be permitteddevelopment as long as it:

Does not exceed 1m above the roof height,

In the case of land within a conservationarea or a World Heritage Site, the ue wouldnot be installed on the principal elevation of

the building, and It is not located in an AQMA.

3.9 If the project also requires an outsidebuilding to store fuel or related equipmentthe same rules apply to that building as forother extensions and garden outbuildings.

3.10 Further information about permitteddevelopment is available on the PlanningPortal website (see Chapter 3 reading links).

Section 75 Agreements

3.11 Section 75 agreements are commonlyknown as planning gain. They attachconditions to the grant of planning


22/6316.


consent, e.g. for the developer to fund newcommunity facilities or road improvements.The legislative basis for planning obligationsis Section 75 of the Town and CountryPlanning (Scotland) Act 1997.

3.12 Section 75 agreements can also be usedto mitigate air quality impacts. Planningand Advice Note 51 (PAN 51) (which wasrevised in 2006) outlines the statutory basis

for applying a combination of planningconditions and legal obligations to addressthe environmental impacts of proposeddevelopments. The use of the equivalentSection 106 agreements in England tomitigate transport impacts of development isextensively covered in the Beacon Councilsguidance Low Emission Strategies.

Assessment and Certication Conditions

An air quality assessment using dispersion modelling shall be carried out and submitted to the local authority todemonstrate that the stack height of the biomass boiler is sufcient to prevent emissions having a signicant negativeimpact on the air quality objectives for NO

2and PM

10. Where emissions are shown to result in an increase, a full

discussion of any potential breaches of air quality criteria shall be provided and an outline of how emissions will be

mitigated.With regards to energy use on site, the biomass boiler must be certied as an exempt appliance in accordance withthe Clean Air Act 1993. Evidence to demonstrate that the boiler has been tested and certied as an exempt applianceshall be provided to the local authority prior to installation. This shall be supplemented with the technical details of thebiomass boiler.

Fuel Quality Conditions

The biomass boiler shall only be operated using clean wood pellets that comply with a recognised fuel quality standard(such as CEN/TS 14961:2005). A written guarantee shall be submitted to the local authority prior to commencementof the development with a declaration that wood pellets conform to a recognised fuel quality standard and will beconsistently used in the biomass boiler. A statement shall be submitted to the local authority specifying the quantity ofwood pellets used in the biomass boiler and the fuel specications in accordance with CEN/TS 14961:2005 or a similarrecognised standard. (The statement shall be obtained from the fuel supplier).

Maintenance Conditions

The biomass boiler shall be associated with a written schedule of maintenance which shall include removal ofash, inspection and maintenance of particulate arrestment equipment, boiler servicing and stack cleaning. Themaintenance schedule shall be submitted prior to installation.

Box 3.1: Examples of Section 75 Conditions

Regulation of Biomass Plant

3.13 In common with other combustionappliances, biomass boilers and CHP unitsare subject to a range of regulatory regimes,

depending on its size (based upon its ratedthermal input) and the type of fuel it burns.

3.14 Biomass fuels generally fall into threecategories depending on whether the fuel isclassied as waste and whether it falls underthe Waste Incineration Directive (WID):

Virgin fuels, e.g. fuels derived from freshtimber

Waste or waste derived fuels exempt fromWID, e.g. agriculture residues

Waste or waste derived fuels covered byWID, e.g. treated wood waste

Regulatory Regimes

Pollution Prevention and Control

3.15 The Pollution Prevention and Control(Scotland) Regulations 2000 (as amended)

(the PPC Regulations) came into force on 14September 2000. Prescribed installationsare regulated by SEPA. Part A installationstend to be larger and more complex andpermits will contain conditions regardingemissions to air, land and water as well ascovering issues such as noise and wasteminimisation. Part B installations tend to besmaller and less complex and permits willcontain conditions regarding emissions to aironly.

Best Available Techniques

3.16 The PPC regulations require SEPA to ensurethat installations are operated in such away that all the appropriate preventative


23/6317.


measures are taken against pollution, inparticular through the application ofBestAvailable Techniques (BAT). The essenceof BAT is that the selection of techniquesto protect the environment should achievean appropriate balance between theenvironmental benets they bring andthe costs to implement them. In seekingthrough the application of BAT to balancecosts to the operator against benets to theenvironment, the PPC Regulations deneBAT as:

The most effective and advanced stagein the development of activities and theirmethods of operation which indicates thepractical suitability of particular techniquesfor providing in principle the basis for

emission limit values designed to preventand, where that is not practicable, generallyto reduce emissions and the impact on theenvironment as a whole; and for the purposeof this denition:

Available techniques means thosetechniques which have been developedon a scale which allows implementationin the relevant industrial sector, undereconomically and technically viableconditions, taking into consideration the

cost and advantages, whether or not thetechniques are used or produced insidethe United Kingdom, as long as they arereasonably accessible to the operator;

Best means, in relation to techniques, themost effective in achieving a high generallevel of protection of the environment as awhole; and

Techniques includes both the technologyused and the way in which the installationis designed, built, maintained, operated and

decommissioned.

3.17 The PPC Regulations require EnvironmentalQuality Standards (EQSs), such as airquality limit values, to be taken intoconsideration. BAT is site specic andthere may be circumstances where SEPAwill require that the performance of a pieceof equipment will exceed BAT, in order toensure that EQSs are not breached.

Waste Incineration Directive

3.18 The incineration or co-incineration of solidand liquid waste in a technical unit is likelyto fall under the Waste Incineration Directive(WID). The WID aims to minimise the

impacts on the environment and humanhealth of emissions to air, land and waterfrom the incineration or co-incineration ofhazardous and non-hazardous waste. Itwas introduced by the European Parliamentand Council on 4 December 2000 andintroduced into Scottish Law by the WasteIncineration (Scotland) Regulations 2003 on1 April 2003.

3.19 All incineration or co-incineration plants mustbe authorised under the PPC regulations.Permits are issued by the ScottishEnvironment Protection Agency (SEPA) thatwill list (i) the categories and quantities ofwaste which may be treated, (ii) the plantsincineration or co-incineration capacityand (iii) the sampling and measurement

procedures which are to be used. Strictrules will be imposed upon the process toretain the waste at a sufcient temperatureto guarantee complete waste combustionand stringent Emission Limit Values (ELVs)will be placed on the emissions from theplant including emissions to air of hydrogenchloride, hydrogen uoride, heavy metals,SO

x, NO

x, dioxins and furans.

3.20 Plants treating only wood waste (with theexception of wood waste which may contain

halogenated organic compounds or heavymetals as a result of treatment with woodpreservatives or coating) are excludedplants under the WID.

The Large Combustion Plant Directive (LCPD)

3.21 The LCPD was introduced by the EuropeanParliament and Council on 23 October 2001.The LCPD introduced measures to controlthe emissions to air of NO

x, SO

2and PM

(dust) from large combustion plants (i.e.

plant with a rated thermal input equal to orgreater than 50MWth. The LCPD denes

three categories of plant with a group ofboilers discharging through a single stackbeing counted as a single combustion plant:

New-new plant which are subjectto request for a licence on or after 27November 2002; these must comply with theDirective and meet ELVs from when they arebrought into operation.

New plant licensed on or after 1 July

1987 but before 27 November 2002, orsubject to a full licence request before27 November 2002 and which came intooperation before 27 November 2003; these


24/6318.


must comply with the Directive and meetELVs from 27 November 2002.

Existing plant licensed before 1 July1987; for this category member statesmay choose to meet required emissions

reduction by 1 January 2008, either throughELVs or a National Emissions ReductionPlan (NERP).

3.22 The UKs NERP set a 2008 emissionsbubble for total emissions of (per annum):SO

2 133,345 tonnes, NO

x 107,720

tonnes and dust 9,659 tonnes. Emissiontrading between participating plants isallowed.

3.23 Individual operators of existing plant mayalternatively choose not to be included in the

ELV or national plan approach and insteadundertake to close down after 20,000operational hours beginning 1 January 2008and ending 31 December 2015. Operatorshad to inform the competent authority (i.e.the Regulators) of their decision before 30June 2004. Implementation of the LCPDis through IPPC (Integrated PollutionPrevention and Control) permits.

The Clean Air Act

3.24 The Clean Air Act 1993 is the primaryregulatory legislation for smaller biomassburning plant (domestic and commercial)that fall outside the PPC system. Localauthorities are the regulating body for theconditions of the Act. The most commonlyknown parts of the Act are those that allowlocal authorities to set up Smoke ControlAreas (Sec. 18) where premises arecommitting an offence if they emit smokeunless using an approved smokeless fuelor an exempt (approved) appliance. TheAct also contains other powers regardingthe control of emissions from large domesticand industrial boilers. Application of the Actto biomass plant is summed up in Chart 4.3and described in more detail below.

3.25 When assessing which regulations applyto a particular biomass boiler it is importantto note that the moisture content of the fuelcan affect the caloric value of that fuel. Anincrease in moisture content leads to lowercaloric values and lower thermal inputs for

a given weight of fuel burnt. For example, afurnace burning fuel with a caloric value of10MJ/kg at 45.4kg/h would represent 126kW(input). A lower moisture content may raise

the caloric value to 20MJ/kg, and this wouldincrease the thermal input to 252kW (input).A unit conversion tool has been developedfor this guidance this is in the form of aspreadsheet which is available to downloadfrom the Environmental Protection UKwebsite (See Chapter 3 reading links).

3.26 It is important to note the limitations of theCAA which was designed to control the

coal smoke smogs of the 20th Century. The

CAA does not directly control emissions

of the smaller particles (PM2.5

and PM10

)

that are the subject of modern air quality

legislation. The cumulative impacts of a large

number of exempt appliances (for example)

could therefore be signicant. Assessing

cumulative impacts is discussed in Chapter 5.

Smoke from Chimneys

3.27 The CAA allows local authorities to createSmoke Control Areas (Sec. 18) in whichvisible smoke emission is prohibited (Sec.20) unless arising from the burning ofauthorised fuel or from the use of an exemptappliance. Procedures for testing andapproving authorised fuels and applianceshave been established via powers given tothe Secretary of State under Secs. 20 and

21. Details of currently authorised fuels andexempt appliances can be found on the UKSmoke Control Areas website (see Chapter3 reading links).

3.28 The acquisition or delivery of a non-approved solid fuel in a Smoke ControlArea (other than to be used in an exemptappliance) is an offence (Sec. 23).

3.29 Smoke Control Areas are relatively commonacross the UK, primarily in urban areas thathave had a concentration of industry and /

or coal red dwellings. Unfortunately, dueto the passage of time and the age andnumber of the individual orders passed toestablish Smoke Control Areas there areno easily available records for the locationof the areas in some authorities (althoughthe local authority can re-designate ifnecessary). The Scottish Air Qualitywebsite contains a map that shows the localauthorities that have a Smoke Control Areain place (http://www.scottishairquality.co.uk/laqm.php?a=s&la_id=).

3.30 Knowledge of the conditions of SmokeControl Areas under the CAA can be lowamongst the general public and also in


25/6319.


some cases amongst installers of smallerwood burning appliances. Some peoplemay be simply unaware that they arecommitting an offence by burning wood innon-exempt appliances (e.g. open grateres). Awareness raising can therefore bean effective tool with information for thegeneral public available on the UK SmokeControl Areas and Environmental ProtectionUK websites (See Chapter 3 reading links).

Emissions from Commercial Premises

3.31 CAA provisions for commercial and industrialpremises apply everywhere i.e. not just in

designated Smoke Control Areas.

3.32 Under Section 1 of the CAA it is an offence to

emit dark smoke from industrial / commercialchimneys unless within the limited periods

allowed by the dark smoke permitted periods

regulations. Sources of dark smoke can

include chimneys, bonres, skip res and

waste disposal / demolition res. Dark

smoke is dened using a Ringelmann smoke

chart; British Standard approved versions of

these are available to purchase online.

3.33 Under Section 4 of the CAA before installing

a furnace (except a domestic furnace) in a

building or xed boiler, the local authoritymust be informed. Any such furnace must

be capable of being operated continuously

without emitting smoke when burning

fuel of a type for which the furnace was

designed. There is no denition of furnace

but a practical interpretation of this word

whenever it appears in clean air legislation

is usually taken as any enclosed or partly

enclosed space in which liquid, solid or

gaseous matter is burned, or in which heat is

produced. Domestic furnaces are dened

as those with a maximum heating capacity of


26/6320.


3.39 Section 12 of the CAA gives local authoritiesthe power to request information on thefurnaces in a building, and the fuels orwastes burnt in them, to properly performtheir functions under Sections 5 11 of theAct. Notice must be served in writing andthe occupier must reply within fourteen days(or a longer time as may be limited by thenotice). Note that whilst this applies to bothdomestic and commercial premises, it isunlikely that any domestic premises will fallunder Sections 5 11. This power couldbe used where local authorities suspectbreaches of regulations are taking place,e.g. where there is a suspicion that wastederived fuels are being burnt in an appliancedesigned for clean, new wood.

Chapter 3 Reading Links

Planning

Beacon Councils Low Emission StrategyGuidance

(http://www.defra.gov.uk/environment/quality/air/airquality/local/guidance)

Climate Change Northwest Biomass Guidesfor Planners

(http://www.climatechangenorthwest.co.uk/news/archive/new-guidance-available-for-householders-developers-and-planners-on-using-biomass-wood-fuel-heating.html)

Planning Portal the Scottish Governmentsonline planning and building regulationsresource

(http://www.scotland.gov.uk/Topics/Built-Environment)

Planning and Renewable Energy on the BISwebsite (includes policy developments)

(http://www.berr.gov.uk/whatwedo/energy/sources/renewables/planning/page18405.html)

Regulation

DECC website

(http://www.decc.gov.uk/en/content/cms/what_we_do/uk_supply/energy_mix/renewable/planning/planning.aspx)

UK Smoke Control Areas website

(http://smokecontrol.defra.gov.uk/)

Domestic smoke on the EnvironmentalProtection UK website

(http://www.environmental-protection.org.uk/neighbourhood-nuisance/domestic-smoke/)

Unit conversion tool can be downloadedfrom www.environmental-protection.org.uk/

biomass


27/6321.

Assessing Potential Impacts

Chapter 4


4.1 Once a local authority receives notication

that a biomass boiler is considered fora particular location (either through theplanning process, enquiries to buildingcontrol or as a Clean Air Act Section 4notication) a number of steps need to befollowed to assess whether the potentialair quality impacts are signicant. The rst(and probably the most important step)is to collect basic information about theproposed boiler to enable a quick risk basedassessment to be made. This may befollowed by the collection of more detailed

information, a screening assessment(such as the screening tool providedby Environmental Protection UK) andproceeding to a more detailed assessmentif screening suggests that there may be asignicant impact. Chart 4.1 sets out anapproach to help local authority ofcers.

4.2 It is important to collate as much informationas possible at the pre-application stage, toensure the initial risk assessment coversall the potential risks of the proposeddevelopment; this should include boiler

design specications and an understandingof the local air quality. It is good practice atthe pre-application stage for developers toengage with local authority representativesfrom environmental protection and planningdepartments to determine if there are anyspecic air quality risks associated with theproposed development. Factors to considerwithin an initial quick risk based assessmentare shown in Table 4.1.

4.3 Note that even if this quick assessmentsuggests that there is very little risk to airquality the proposed boiler should still bechecked to ensure it is compliant with theCAA and / or whether it needs a permit tooperate (see Charts 4.2 and 4.3). Suitableconditions can then be added to the

planning permission if necessary to ensureregulatory conditions are met, e.g. that theboiler is certied as an exempt appliance inaccordance with the CAA or that a permit isgained from the appropriate regulator. Therisk assessment of the proposed schemerelates to the risk to air quality at relevantreceptors in the existing environment fromthe proposed development and to anyadditional receptors that may be included aspart of the proposed development.

Chart 4.1: Factors to Consider in a Quick Risk Based Assessment

Permission would be granted subject tosteps followed in Chart 4.2

Planning permission will not ordinarily be grantedunless:(a) The proposed boiler is replacing an existingcoal or oil burning appliance.(b) Developers have proven no signicantindividual or cumulative impacts (includingemissions from vehicles delivering biomass fuels)(c) Plant utilises suitable abatement technology tolimit emissions (Chapter 6)

The developers must demonstrate that thereare no signicant individual or cumulative airquality impacts. The developer must also takeinto consideration the emissions from vehiclesdelivering the biomass fuel.

Where the term signicant is used, it will bebased on the professional judgement of the localauthority ofcer. See Environmental ProtectionUK Planning Guidance (Chapter 4 ReadingLinks)

Ambient levels are those at the nearby receptorsand are the sum of background concentrationstogether with contributions from other nearbypollution sources, e.g. a busy road within 10m

Will the proposed biomass boiler be situatedin, or near, to existing AQMAs or hotspots?

Are ambient levels within 10% of objectives?

(Appendix D)

Does screening assessment indicatesignicant air quality impact?

No

No

No

Yes

Yes

Yes


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4.4 Note that the CAA is not necessarilysufcient to determine that there will not

be adverse impacts from a biomass boiler.In addition to satisfying the CAA it is stillnecessary to check compliance of the plantand that it will not result in a nuisance or bedetrimental to human health.

4.5 If the quick assessment suggests that thebiomass boiler may pose a risk to air qualitythen more detailed information about thebiomass boiler will be required. Collectingthis at an early stage is key to making agood assessment however it is a step thatmany local authorities have found to bedifcult. There are several reasons for this:

Decisions on which renewable energytechnologies to use are often left until

Table 4.1: Factors to Consider in a Quick Risk Based Assessment

Emissions performance for smaller appliances depends heavily on thefuel used. Clean, virgin wood fuels are likely to provide the best emissionperformance. Appliances burning wood pellets were thought generally to havelower emissions than those burning larger wood particles (i.e. chips and logs);however recent test data has shown that chip and pellet boilers can have similaremissions performance.

The performance of the boiler will be dependent upon the consistency of fuelsupply. Developers need to ensure there is a sufcient and secure supply of therequired fuel quality for the boiler to achieve good emissions performance.

Geography

Fuel substitution/ alternatives

Boiler size

Emissions performance

Fuel

The potential risk of a breach of air quality standards is increased if the boiler isin or near (and could potentially affect) an AQMA. If air quality in the area aroundthe boiler is marginal there is a risk that emissions from the boiler could trigger a

new AQMA.Does the terrain and surrounding land use result in air quality conicts, i.e. isthe installation in a valley with nearby properties at stack height or are thereats in the vicinity of the development that may put local residents at a heightcomparable to the stack emissions.

If the biomass boiler is displacing a similar appliance running on a clean fuelsuch as gas then it will negatively affect air quality. Conversely if the boilerdisplaces dirtier fuels such as coal or oil there may be little, or even a positive,effect on air quality. If the boiler is being installed on a site with no currentcombustion appliances some consideration of alternative fuels available shouldbe made i.e. are clean fuels such as mains gas available, or are the realisticalternatives coal and oil?

Installed capacity will give an indication of emissions and the appropriateness ofthe boiler plant.

Although a detailed assessment of the emissions performance of the boiler isunlikely to be available at this stage some simple questions can be asked, e.g.is it an exempt appliance? How does it compare against the general criteria inTable 2.1?

after outline planning permission has beengranted.

The costs of the technical consultants andair quality assessments required to specify abiomass boiler can be high; developers maywant to secure planning permission beforeincurring such costs.

Planners and developers are often unawarethat biomass boilers can have a detrimentalimpact on local air quality and that theemissions from different boiler types canvary signicantly.

4.6 Flagging up air quality issues with planningcolleagues and developers at the earlieststage possible is therefore extremelyimportant. The developers informationleaet produced alongside this guidance


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can be used for this purpose (www.environmental-protection.org.uk/biomass).

4.7 A biomass boiler information request formhas also been produced alongside thisguidance which local authorities can tailor

to meet their needs in order to requestinformation from developers. Again it isgood practice to vary the depth of theinformation requested according to therisk to air quality suggested by the initialquick assessment. Where the developeris unable to supply information on theirproposed appliance(s) generic guresmay be available to use in screeningassessments. However if this assessmentsuggests that air quality impacts may besignicant, developers should be allowed

the opportunity to supply more detailedinformation on their proposed appliance toenable a more accurate assessment to bemade. See Chapter 4 Reading Links

4.8 Once basic information has been collecteda screening tool can be used to make aninitial assessment. If this shows that theimpact may be signicant the developercan then be asked to use more detaileddispersion modelling to make a moredetailed assessment of the emissions and

stack height. If the impact is still judged tobe signicant the developer can be asked touse abatement technology, choose a cleanerboiler or, if none of these are suitable, usea different renewable energy technology. Asimple ow diagram of the process is shownin Chart 4.2. The process for checking CAAcompliance is shown in Chart 4.3.

4.9 Energy Supply Companys (ESCO)contracts, which relate to quality standardsof equipment, maintenance and fuelsupply, may exist between developers and

installers. ESCO contracts not-withstanding,it is the developers responsibility to ensurethe plant operates to the correct standards.To achieve certain air quality amenities itmay be necessary to have a tall stack; ifvisual amenity is of high importance and theair quality impact is unacceptable then analternative location or technology may berequired.

4.10 There is no specic Government guidanceon determining the signicance of air quality

impacts within an air quality assessmentand the denition of what is a signicantimpact therefore ultimately lies with thejudgement of the individual local authority.

The Environmental Protection UK documentDevelopment Control: Planning for AirQuality contains guidance on assessingsignicance which can assist is this area(updated in April 2010).

4.11 To support local authority duties underLAQM three help desks have beenestablished by DEFRA and the DevolvedAdministrations - Monitoring, Modelling andEmissions Inventories (0870 190 6050),Review and Assessment (0117 328 3668)and Action Planning (0870 190 6050).

4.12 Smaller biomass boilers installed in existingdwellings may be tted without noticationto, or involvement of, the local authority. Itis important to note that the provisions of

the CAA in its existing form is not enough toensure that localised increase of PM2.5

andPM

10concentrations do not occur, especially

if a number of small biomass boilers areinstalled in a particular geographical area.For all properties in a Smoke Control Areaany installed appliances should be exemptand use permitted fuels.

Energy Statements and Basic Information

About a Biomass Boiler

4.13 All local authorities in Scotland are nowrequired to set renewable energy targetsfor all new developments and developmentplans

epuk scotland biomass guidance nov 2010

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