CHAPTER 18.0 CLIMATE CHANGE€¦ · climate change assessments for planning and permitting purposes for a wide range of developments including Energy from Waste facilities across

2565-01 / Proposed Extension to the Allington IWMF PEIR Main Report July 2020 18-i

CHAPTER 18.0 CLIMATE CHANGE

18.0 CLIMATE CHANGE ..................................................................................... 18-1

Introduction ................................................................................................... 18-1

Legislation, Policy and Guidance .................................................................. 18-2

Consultation .................................................................................................. 18-6

Assessment Methodology ............................................................................. 18-9

Baseline ...................................................................................................... 18-19

Assessment of Effects ................................................................................ 18-20

Summary .................................................................................................... 18-21

APPENDICES (bound separately in Volume 3)

Appendix 18-1 ................................................................................. Carbon Assessment

Please note that a full list of acronyms is provided the contents to this PEIR and should

be referred to when reading this Chapter.

2565-01 / Proposed Extension to the Allington IWMF PEIR Main Report July 2020 18-1

18.0 CLIMATE CHANGE

Introduction

18.1.1 This Chapter of the PEIR considers the carbon impact of the treatment of

residual waste in the Proposed Extension. The Existing Station is not included

within the scope of this assessment as an assessment has previously been

undertaken for this consented operation. Therefore, only the emissions from the

Proposed Extension and associated flue within the combined stack have been

assessed. The assessment takes into account the following factors when

determining the carbon impact of the development:

• Carbon dioxide emissions released from the combustion of fossil-derived

carbon in the waste processed in the Proposed Extension;

• Emissions of other greenhouse gases from the combustion of waste in the

Proposed Extension;

• Emissions from the combustion of auxiliary fuel in the auxiliary burners at

the Proposed Extension;

• Emissions from the transport of waste and reagents to and residues from

the Site associated with the operation of the Proposed Extension; and

• Emissions offset from the export of electricity from the Proposed Extension.

18.1.2 The findings of the assessment are summarised in this PEIR chapter, with the

full assessment presented as Technical Appendix 18.1.

Competence

18.1.3 This Chapter and supporting Technical Appendix have been prepared by Katie

Hampton and reviewed by Stephen Othen at Fichtner Consulting Engineers.

Katie (BSc, AMIEnvSc) is an associate member of the Institution of

Environmental Sciences (IES). Katie has experience in undertaking carbon and

climate change assessments for planning and permitting purposes for a wide

range of developments including Energy from Waste facilities across the UK.

Stephen (MA, MEng, CEng, MIChemE) has 24 years’ experience working in

engineering consultancy services, environmental services and technical

advisory work. Stephen has supported most of Fichtner’s Energy from Waste


and Biomass projects, and is an authority on energy and environmental

legislation, having acted as Expert Witness in this context at public inquiries.

Legislation, Policy and Guidance

Legislation

18.2.1 The Town and Country Planning (Environmental Impact Assessment)

Regulations 2017 (as amended) introduced a requirement to consider climate

and greenhouse gas emissions. Schedule 4 of the regulations states: “A

description of the factors specified in regulation 4(2) likely to be significantly

affected by the development: … climate (for example greenhouse gas

emissions, impacts relevant to adaptation)” and “A description of the likely

significant effects of the development on the environment resulting from, inter

alia: … (f) the impact of the project on climate (for example the nature and

magnitude of greenhouse gas emissions)…”

18.2.2 The Infrastructure Planning (EIA) Regulations 2017 require information on

“…climate (for example greenhouse gas emissions, impacts relevant to

adaptation)” to be included within the Environmental Statement, alongside a

description of the likely effects of the development on the environment including

“the impact of the project on climate (for example the nature and magnitude of

greenhouse gas emissions)”.

18.2.3 Due to its nature and scale, the Proposed Extension has the potential to either

produce significant greenhouse gas (GHG) emissions (or significantly reduce

greenhouse gas emissions compared to the baseline scenario, i.e. the disposal

of waste within a landfill). Therefore, this PEIR includes a carbon assessment.

The detailed methodology for the assessment, including defining the baseline

scenario, is presented within further detail in the sections below.

18.2.4 The UK government set a commitment to reduce GHG emissions in the UK to

50% of 1990 levels by 2025, and to 80% by 2050 through the implementation of

the Climate Change Act 2008, the framework for UK climate change policy. More

recent legislation (The Climate Change Act 2008 (2050 Target Amendment)

Order 2019) has introduced a new binding target of “net zero by 2050”.


National Policy

18.2.5 The relevant National Policy Statements to the development are EN-1 (Energy)

and EN-3 (Renewable Energy Infrastructure). In relation to carbon and

greenhouse gas emissions, Section 2.2 of EN-1 sets out the road to meeting

greenhouse gas emissions targets by 2050 and describes how the UK must

reduce its dependence on fossil fuels, pursue its objectives for renewables and

ensure that electricity consumed is almost exclusively from “low-carbon”

sources. Section 1 of EN-3 identifies that a significant increase in generation

from large-scale renewable energy infrastructure is necessary to meet the 15%

renewable energy target. Specifically, in regards to Energy from Waste, section

2.5 of the statement identifies the following:

“The recovery of energy from the combustion of waste, where in accordance

with the waste hierarchy8, will play an increasingly important role in meeting

the UK’s energy needs. Where the waste burned is deemed renewable, this

can also contribute to meeting the UK’s renewable energy targets. Further, the

recovery of energy from the combustion of waste forms an important element

of waste management strategies in both England and Wales”

18.2.6 The National Planning Policy Framework (NPPF; 2019) sets out the

government’s planning policies for England and how they are expected to be

applied. In relation to carbon and greenhouse gas emissions, section 14 of the

NPPF states that:

“The planning system should support the transition to a low carbon future in a

changing climate, taking full account of flood risk and coastal change. It

should help to: shape places in ways that contribute to radical reductions in

greenhouse gas emissions, minimise vulnerability and improve resilience;

encourage the reuse of existing resources, including the conversion of existing

buildings; and support renewable and low carbon energy and associated

infrastructure.”

Local Planning Policy

18.2.7 The Site is located in the majority within the Tonbridge and Malling Borough,

however a small section of the site adjacent to the existing access lies within the

Maidstone Borough Council area. Therefore, a review of local planning policy


for both Tonbridge and Malling Borough Council (TMBC) and Maidstone

Borough Council (MBC) has been undertaken as this is deemed appropriate for

the context of the Proposed Extension.

18.2.8 TMBC (The Borough) is in the process of preparing a new Local Plan, which has

been consulted on and is currently at the examination phase. The Stage 1

hearing sessions were postponed but have now been rescheduled for October

and November 2020. Once the hearing sessions have been undertaken, the

plan will be modified accordingly to reflect the recommendations made by the

Inspector. Once finalised and adopted, the Local Plan will form part of the

council’s Development Plan up to 2031. Strategic Objective 9 is to “ensure

development mitigates its impact on the environment and is resilient to the

effects of climate change”. The Sustainability Appraisal produced to inform the

Local Plan identifies some key sustainability issues which affect TMBC – one

being “reducing the amount of non-hazardous waste sent to landfill and increase

the reuse and reducing of waste”. The appraisal also sets out key objectives,

including “to ensure that the borough responds positively, and adapts to, the

impacts of climate change” and “to reduce waste and achieve sustainable waste

management”. The Proposed Extension will reduce the amount of waste sent to

landfill, have a positive impact on climate change compared to the baseline and

promotes sustainable waste management by handling residual waste following

recycling only.

18.2.9 Policy CP1 in TMBC’s currently adopted Core Strategy seeks to achieve high

quality sustainable development in the borough. It is considered that the

development of renewable and low-carbon technologies such as the Proposed

Extension supports local sustainable development. The Managing Development

and the Environment Development Plan Document (MDE DPD) forms part of

the Local Development Framework for the borough, and aims to address issues

which may not be covered in the Core Strategy, such as how to “minimise the

impact of new development on climate change by reducing carbon emissions,

optimising the harnessing of energy from renewable sources and minimising

waste”. The MDE DPD sets out objectives including “optimising the use of low

or zero carbon technologies”. The Proposed Extension will lead to a reduction

in carbon emissions through the following:


18.2.10 offset of grid electricity with electricity generation from the Proposed Extension

and the avoidance of carbon emissions from landfill (refer to paragraph 18.4.21);

.

18.2.11 Key local issues set out in the MBC Local Plan include the provision of local

infrastructure to support new development including “sustainable waste

management” and “energy infrastructure”, both of which will be met by the

Proposed Extension.

Guidance

18.2.12 The Committee on Climate Change, the UK’s independent advisory body to the

government, recently published a technical report (referred to hereafter as the

CC Report) which sets out recommendations to the UK government on how to

achieve the target of net zero carbon emissions by 2050. The CC Report sets

out how key biodegradable waste streams should be diverted from landfill within

the UK alongside an increase in recycling. To achieve this and deliver

substantial emissions reductions in the waste sector, the report advises that key

investment is required in alternative waste treatment facilities (such as

anaerobic digestion, mechanical-biological treatment and energy from waste).

The report acknowledges that a lack of investment in these areas may

encourage the export of waste.

18.2.13 The CC Report envisages a future generation mix where renewables dominate,

which includes generation from both hydro and energy from waste plants. The

continued development and investment in low carbon technologies will be key

in achieving a net-zero future. The intermittency of renewables is recognised

and there is support for base-load low-carbon generating plants. Consequently,

energy from waste (which supplies a steady and reliable source of renewable

energy) would play a key role in UK renewable power generation and contribute

to achieving a net zero future.

18.2.14 The Waste Management Hierarchy ranks waste management options in order

of sustainability, with more sustainable waste management options placed

higher in the Waste Management Hierarchy. The thermal treatment of residual


waste in an efficient energy-from-waste plant is a recovery operation, meaning

it should be favoured over the disposal of waste in a landfill.

18.2.15 The Institute of Environmental Management and Assessment (IEMA), the

largest professional body for environmental practitioners, has published

guidance on the approach to EIA for carbon emissions, titled ‘Assessing

Greenhouse Gas Emissions and Evaluating their Significance’ (2017). The

guidance sets out areas for consideration at all stages of the assessment to

assist EIA practitioners in taking an informed approached to the treatment of

GHG emissions within an EIA.

Consultation

18.3.1 The proposed scope of this Climate Change Assessment was set out in the

Scoping Report submitted to the Planning Inspectorate (PINS) in November

2019 (see Appendix 6-1). A Scoping Opinion was received from PINS in

December 2019 as adopted by the Secretary of State. Table 18.1 below

summarises the relevant response from PINS in relation to climate change:

Table 18.1: Consultation responses

Consultee Comment Response to Consultation

Scoping Responses

PINS (3.3.13) The Inspectorate states that the assessment should include a description and assessment (where relevant) of the likely significant effects the Proposed Development has on climate, such as having regard to the nature and magnitude of greenhouse gas emissions.

This Chapter addresses the impact of the Proposed Extension on climate change, with the full carbon assessment included in Technical Appendix 18.1.

PINS (6.12.3) The Inspectorate states that, the effects of the Proposed Extension on climate would be considered through a qualitative assessment; however, no further information on how this assessment will be undertaken has been provided. The Inspectorate state that the assessment should ensure the qualitative assessment clearly explains how carbon emissions are calculated.

This Chapter clearly sets out how carbon emissions for the Proposed Extension have been calculated, with the full methodology presented in Technical Appendix 18.1.

Meetings

None


Data Sources

18.3.2 The data sources and their relevance to this assessment are shown in Tables

18.2 and 18.3 below. This data covers both the activities to occur as part of the

Proposed Extension (project-specific data, such as transport distances) and the

emissions factors for these activities. Emissions factors have been carefully

selected, with multiple emissions factors considered when calculating the

carbon benefit of grid displacement (the reduction in carbon emissions when

comparing the carbon intensity of the UK grid and the carbon intensity of the

electricity exported from the Proposed Extension) (refer to paragraph 18.4.26).

Table 18.2: Data sources

Guidance Relevance to Assessment

IPCC Guidelines for Greenhouse Gas Inventories, Vol 2, Table 2.2 Default Emissions Factors for Stationary Combustion in the Energy Industries, Municipal Wastes (non-biomass) and Other Primary Solid Biomass

Emissions factors:

• N2O default emissions factor: 0.04 kg N2O/tonne waste

• CH4 default emissions factor: 0.3 kg CH4/tonne waste

United Nations Framework for Climate Change Global Warming Potentials

Global Warming Potentials:

• GWP – N2O to CO2: 310 kg CO2e/kg N2O

GWP – CH4 to CO2: 25 CO2e/kg CH4

DEFRA, 2019, “Greenhouse gas reporting: Conversion factors 2019”

Emissions factor:

Emissions from gasoil: 0.25 tCO2e/MWh

DEFRA, 2019, “Fuel Mix Disclosure Table – 01/04/2018 – 31/03/2019”

Emissions factor:

Natural gas CO2 emissions: 349 g/KWh

DEFRA, 2014, “Review of Landfill Methane Emissions Modelling (WR1908)”

Landfill assumptions:

• Degradable decomposable organic carbon content (DDOC): 50%

• CO2 percentage of LFG: 43%

• CH4 percentage of LFG: 57%

• LFG recovery efficiency: 68%

• Methane captured used in gas engines: 90.9%

• Methane leakage through gas engines: 1.5%

• Landfill gas engine efficiency: 36%

Resource Futures, 2013, “Defra EV0801 National Compositional estimates for local authority collected waste and recycling in England, 2010/11” (Kerbside Residual)

Waste composition data

Environment Agency Wales/SLR, 2007, "Determination of the Biodegradability of Mixed Industrial and Commercial Waste Landfilled in Wales"

DEFRA, 2014, “Energy from waste: A guide to the debate”

Guidance used in carbon assessment methodology

DEFRA 2014, “Energy recovery for residual waste – a carbon based modelling approach”

Basis/main structure for carbon assessment methodology


IEMA, 2017, “Environmental Impact Assessment Guide to Assessing Greenhouse Gas Emissions and Evaluating their Significance”

Basis for EIA methodology/PEIR Chapter structure

Where CO2e = carbon dioxide equivalent

Table 18.3: Transport assumptions included in the assessment

Parameter Units Value Source

Average payload – Waste to landfill tonnes 18 Project-specific assumption Average payload – Waste to the

Proposed Extension tonnes 18

Payload – IBA tonnes 20

Payload – APCr tonnes 24.5

Payload – Reagents 20 tonnes

Articulated lorry CO2 factor - 100% loaded

kg CO2/km 1.02676 BEIS "Greenhouse gas reporting:

conversion factors 2017" HGV (all

diesel) Articulated (>3.5- 33t)

Articulated lorry CO2 factor - 0% loaded

kg CO2/km 0.67711

Waste distance to landfill (one way) km 48 Project-specific assumption Waste distance to the Proposed

Extension (one way) km 89

IBA distance to recovery km 27

APCr distance to disposal/recovery km 370 Assumed to be transported to

Knostrop Treatment Works in Leeds[1]

Lime distance to Site km 344 Tarmac Lime Quarry, Buxton

Activated carbon distance to Site km 72 Environmental Protection Industries

Ltd, Essex

Ammonia distance to Site km 402 CF Fertilisers UK Ltd, Ince

Fuel oil distance to Site km 200 Watsons Fuel UK Ltd, Chippenham

Mass of waste tonnes 300,000 Nominal waste throughput

Mass of IBA tonnes 72,000 Approximately 24% of input waste

Mass of APCr tonnes 16,000 Approximately 5% of input waste

Mass of lime tonnes 4,000 Project-specific assumption Mass of activated carbon tonnes 80

Mass of ammonium hydroxide (SNCR reagent)

tonnes 480

Mass of fuel oil tonnes 415

[1] Worst case scenario (greatest distance) assumed – in reality, only a small percentage of the APCr is expected to be transported here as a more local solution will be sought.


Assessment Methodology

Scope

18.4.1 The objective of this assessment is to assess the carbon impact of GHG

emissions associated with the Proposed Extension against the baseline

scenario of disposing of the annual tonnage of waste in a landfill and generating

electricity using the marginal technology (refer to paragraph 18.4.21).

18.4.2 The elements of the baseline landfill comparator included within the assessment

are identified in Table 18.4.

Table 18.4: Elements of the Landfill Comparator to be included in the Assessment

Comparator Element included

Landfill

Emissions of methane (CO2e) released to atmosphere in the fraction of landfill gas that is not captured. This is calculated taking into account the following elements:

• Biogenic carbon

• Total DDOC content (biogenic carbon not sequestered)

• Methane in LFG, of which: o Methane captured o Methane oxidised in landfill cap o Methane released to atmosphere directly

Methane leakage through gas engines

Emissions offset from the generation of electricity from landfill gas, taking into account the following elements:

• Methane captured

• Methane flared

• Methane leakage through gas engines

• Methane used in gas engines

• Fuel input to gas engines Power generated

18.4.3 The elements of the Proposed Extension scoped into the carbon assessment

are identified in Table 18.5.


Table 18.5: Elements of the Proposed Extension to be included in the Assessment

Development phase

Element of the Proposed Extension

Operation

Emissions released from the combustion of fossil carbon in the waste

Emissions of other greenhouse gases from the combustion of waste

Emissions from the combustion of auxiliary fuel in the auxiliary burners

Emissions from the transport of waste, reagents and residues to and from the site

Emissions offset from the export of electricity from the proposed development

18.4.4 The methodology within this Chapter differs from the methodology applied in

the rest of the PEIR. There is limited guidance on the assessment of carbon

and greenhouse gas emissions for the purposes of undertaking an

Environmental Impact Assessment. It is difficult to quantify the impact of carbon

and greenhouse gas emissions and the receptor will be the worldwide climate.

18.4.5 It is acknowledged that the other chapters within the PEIR consider two

scenarios – one with and one without the HWRC. The HWRC has not been

included within the scope of the carbon assessment as its operation will not

result in the direct release of greenhouse gas emissions. It is acknowledged

that there may be some indirect carbon emissions associated with the transport

of waste to and from the HWRC in addition to minor operational carbon

emissions from power consumption, lighting etc.

Study Boundaries

18.4.6 A fully comprehensive GHG assessment will typically cover all life cycle stages

including construction, operation and end-of-life stage (i.e. decommissioning

and demolition). The IEMA (2017) guidance states that certain life cycle stages

can be excluded as long as this approach is justified; it is expected that “direct

GHG emissions from a project’s use and/or operation would be reported as a

minimum” within the boundaries of the study. The chosen study boundaries are

set out and justified in paragraphs 18.4.7 to 18.4.9 below.

18.4.7 The emissions associated with the construction and end-of-life stages will be

minor when compared to the carbon impact over the operational lifetime of the

Proposed Extension. Therefore, construction emissions and end-of-life

emissions (e.g. decommissioning and site closure) have been scoped out of the

assessment in relation to carbon and greenhouse gas emissions. This is


supported by the IEMA guidance which states that a balance should be “struck

between the amount of GHG emissions emitted by the project and the effort

committed to the actual GHG assessment”.

18.4.8 The adopted Scoping Opinion requests that carbon emissions are calculated

for the following three matters:

1. The combustion of waste from the operation of the Proposed Extension;

2. The displacement of heat and power which would otherwise be generated

from the combustion of fossil fuel; and

3. The alternative waste management solutions for the waste to be processed

at the Proposed Extension (assumed to be landfill).

The three matters above have been considered when calculating carbon

emissions for the Proposed Extension. As a conservative measure it has been

assumed that the Proposed Extension will not export heat. If the Proposed

Extension was to export heat the net carbon emissions would be lower. The

CHP assessment presented in Appendix 5-6 provides further detail on the

viability of heat export from the Facility.

18.4.9 The IAQM (2017) Guidance explains that the boundary of assessment should

consider the physical boundary, geographical location and temporal boundary.

A physical boundary cannot be defined – the effects will be on the worldwide

climate. The temporal boundary has been taken into consideration with the

assessment of a future baseline (18.4.26) and the operational lifetime of the

development (refer to paragraph 18.4.10). The geographical location of the

Proposed Extension has been taken into consideration via the assessment of

transport emissions.

Study Period

18.4.10 The Proposed Extension will operate for as long as it is required, however it is

expected to have an operational lifetime of at least 25 years. Therefore, this has

been chosen as a suitable long term Study Period for the assessment.


Level and Significance of Effect

18.4.11 The IEMA (2017) guidance explains that in the absence of any significance

criteria or a defined threshold, it might be considered that all GHG emissions

are significant. Climate change has the potential to lead to significant

environmental effects on all topics in the EIA directive (population, fauna, soil

etc.) The guidance states that: “When evaluating significance, all new GHG

emissions contribute to a significant negative environmental effect; however;

some projects will replace existing development that have higher GHG profiles.

The significance of a project’s emissions should therefore be based on its net

impact, which may be positive or negative.”

18.4.12 The significance of effect is defined in accordance with the IEMA (2017)

guidance and therefore the Proposed Extension will have either a net positive

significant impact (i.e. a reduction in carbon emissions compared to the

baseline), a net negative significant impact (i.e. an increase in carbon emissions

compared to the baseline) or zero impact/significance (i.e. no change in carbon

emissions compared to the baseline).

18.4.13 The ultimate goal of establishing a baseline is being able to assess and report

the net GHG impact of the Proposed Extension. Therefore, the primary aim of

this assessment is to estimate the net GHG impact and significance associated

with the Proposed Extension compared to the baseline landfill scenario.

Cumulative impacts

18.4.14 In relation to cumulative effects, the IEMA guidance acknowledges that “GHG

emissions from all projects will contribute to climate change; the largest inter-

related cumulative effect”. Appendix C of the guidance describes how “GHG

impacts are considered to be exclusively cumulative impacts because no single

project makes a significant contribution to global climate change”. As the scope

for cumulative effects has the potential to be unlimited, it is not viable to assess

cumulative effects resulting from the operation of the Proposed Extension. It is

acknowledged that the methodology applied within the assessment differs to

other chapters of the PEIR – refer to paragraph 18.4.4.


Limitations and assumptions

18.4.15 The following limitations and uncertainties have been identified in the

assessment:

• There is considerable uncertainty in literature surrounding the amount of

biogenic carbon that is sequestered in landfill.

• The future of the UK electricity grid mix is uncertain; therefore, the current

‘marginal’ comparator has been used to assess grid displacement (refer to

paragraph 18.4.21).

18.4.16 The following conservative assumptions have been used in the assessment:

• There will be 10 start-ups a year where the gasoil-fired auxiliary burners will

be in operation (in reality, there will typically be around 4 start-ups and

shutdowns per year).

• Recent bidding of Energy from Waste plants into the capacity market means

they are competing primarily with Combined Cycle Gas Turbines (CCGT),

gas engines and diesel engines. CCGT has been used as the comparator

for displaced electricity and may possibly be conservative compared to the

other options providing balancing services.

• A sequestration rate of 50% for biogenic carbon in landfill has been applied.

• A relatively high landfill gas capture rate of 68% gas been used.

• The methodology used to calculate the carbon burden of transporting the

waste is conservative as it may be possible to coordinate HGV movements

to reduce the number of trips.

• The Proposed Extension will generate approximately 31.4 MWe of

electricity, of which approximately 28.7 MWe will be exported to the grid.

This is conservative, as the development may generate more electricity at

the upper-end of the NCV (approximately 14 MJ/kg) range. The assessment

has currently been undertaken based on the nominal design capacity of the

(8,000 hours operation, 300,000 tonnes per annum of waste). The

development may operate for more than 8,000 hours per annum

(consequently processing more waste per annum) if there are limited

periods of shutdown/outage.

• The assessment has assumed that the Proposed Extension will not export

heat. The Proposed Extension is designed as a combined heat and power

plant (CHP), and if heat is exported this would significantly increase the


carbon benefits of the development. As detailed in the Heat and Power Plan,

there are potential CHP opportunities available which are being considered.

Detailed Methodology

18.4.17 The standard methodology described earlier in the PEIR does not apply to this

Chapter – refer to paragraphs 18.4.4 to 18.4.5. As the receptor for GHG

emissions will be the worldwide climate, it is not feasible to assess the sensitivity

of individual receptors. The environmental effects scientifically linked to global

warming include polar ice melts, sea level rise, ocean acidification, increases in

extreme weather events and ecosystem disruption among other effects. In

addition, the magnitude of the impact of GHG emissions cannot be determined.

For the purposes of this Chapter, an alternative methodology has been applied

as described in the following sections.

Parameters

18.4.18 It is acknowledged that certain design parameters such as building layouts etc

are subject to detailed design of the Facility. The ‘Rochdale Envelope’ approach

has been employed as certain details of the Proposed Extension (e.g. precise

dimensions of structures) have not yet been confirmed. However, a change in

the parameters adopted under the Rochdale Envelope would not affect the

outcome of the carbon and greenhouse gas emissions assessment, due to the

nature of the parameters used in the carbon assessment.

Baseline

18.4.19 The IEMA (2017) guidance defines the baseline as a reference point against

which the impact of a new development can be compared against (sometimes

referred to ‘business as usual’, where assumptions are made on current and

future greenhouse gas emissions). The baseline can be in the form of:

A) “GHG emissions within the agreed physical and temporal boundary of a

project but without the proposed project; or

B) GHG emissions arising from an alternative project design and

assumptions”.


18.4.20 The Proposed Extension is a ‘new project’, therefore a current baseline cannot

be established in relation to emissions from the site boundary of the Proposed

Extension prior to commencement of development. In this instance, there are

zero GHG emissions to report. Furthermore, as the impact of GHG emissions

from the development will be worldwide, a physical boundary to their impact

cannot be defined. Therefore, option b) has been chosen to establish the

baseline.

18.4.21 For this assessment, the ‘alternative project design and assumptions’ for the

Proposed Extension will be sending the waste to landfill as this is currently the

most likely alternative destination for the waste, and generating electricity via

gas-fired power stations, as this is the current ‘marginal’ technology. This is

supported by the DEFRA guidance document ‘Energy from Waste – A guide to

the debate’ which states that “a gas fired power station (Combined Cycle Gas

Turbine – CCGT) is a reasonable comparator as this is the most likely

technology if you wanted to build a new power station today".

18.4.22 When considering the landfill comparator it is acknowledged that when waste is

disposed of in a landfill, the biogenic carbon degrades and landfill gas is

produced (comprised predominately of methane and carbon dioxide). Some of

the methane in this landfill gas can be recovered and used to generate

electricity, through combustion in a landfill gas engine. Both the carbon dioxide

released in landfill gas and the carbon dioxide produced as a result of

combustion in landfill gas engines (alongside the escape of gas from the

collection system and the landfill cap itself) are derived from the biogenic carbon

in the waste. Carbon from biogenic sources has a neutral carbon burden,

therefore, have been excluded from the calculations. Consequently, the focus

of the calculations is the methane which is released to atmosphere.

18.4.23 Landfill is typically the most likely alternative destination for residual waste if it

was not to be processed within a UK EfW plant. Residual waste treatment

capacity varies around the UK with some regions closer to foreign export

markets. It is acknowledged that currently, a significant proportion of waste from

the surrounding areas to the Proposed Extension is transported to Dover, where

it is then exported overseas for processing. The ‘need’ for the developing the


Proposed Extension relates in part to securing future UK-based waste

management solutions.

18.4.24 Whilst the export of waste is permissible, the energy recovered from this waste

would not contribute towards UK renewable energy targets and would

effectively be a lost resource to the UK. The UK government is keen to support

domestic markets where that can provide better environmental outcomes, to

ensure that the UK benefits from the energy generated from UK waste. Recent

estimates indicate that over the past few years the UK has been reducing the

amount of waste exported (‘UK Energy from Waste Statistics 2018’, Tolvik,

2019).

18.4.25 Taking the above into consideration, landfill is considered to be a suitable

baseline comparator for the purposes of the assessment. Should the alternative

baseline be considered (exporting the waste abroad for processing), it is

expected that the conclusions of the assessment will remain the same and that

the Proposed Extension would have a net benefit as the transport emissions

associated with the export of waste abroad will be significantly greater than the

transport emissions associated with processing the waste within the UK.

Future Baseline

18.4.26 According to the IEMA (2017) guidance, future baselines should capture both

direct and indirect (‘operational and use’) GHG emissions. This has been

reflected by the assessment of transport emissions (indirect) in addition to direct

emissions. For the purposes of this assessment, the Proposed Extension is

estimated to have a 25-year lifetime (refer to paragraph 18.4.10), and this has

been taken into consideration when assessing operational emissions and the

net impact of the Proposed Extension. In addition, a change in UK grid mix over

time and how this affects the net impact of the Proposed Extension has been

examined within a sensitivity analysis.

Operational Phase

18.4.27 Although the quantification of GHG emissions for an EIA or PEIR may vary in

methodology and approach between projects, it is expected that in almost all


cases, a calculated (not measured) approach is taken because these are

completed in advance of a project commencing development. The assessment

has been undertaken in line with IEMA (2017) guidance, which recommends

the following structure to calculate GHG emissions:

𝐺𝐻𝐺 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛/𝑟𝑒𝑚𝑜𝑣𝑎𝑙 = 𝐺𝐻𝐺 𝑒𝑚𝑖𝑠𝑠𝑖𝑜𝑛 𝑓𝑎𝑐𝑡𝑜𝑟 × 𝐴𝑐𝑡𝑖𝑣𝑖𝑡𝑦 𝑑𝑎𝑡𝑎

18.4.28 The DEFRA (2014) document ‘Energy from waste: A guide to the debate’

indicates that biogenic carbon dioxide released from the combustion of waste

or the burning of landfill gas should be ignored in this type of assessment.

Therefore, the calculations exclude carbon dioxide produced as a result of

combustion in landfill gas engines which is derived from the biogenic carbon

content of the waste in line with government guidance.

18.4.29 In accordance with Volume 5 of the Intergovernmental Panel on Climate

Change (IPCC) (2006) Guidelines for Greenhouse Gas Inventories, it has been

assumed that all of the carbon in the waste is converted to carbon dioxide in the

combustion process as waste incinerators have combustion efficiencies of close

to 100%.

18.4.30 The factors identified in Table 18.5 have been taken into consideration when

calculating the total carbon emissions associated with the operational phase of

the Proposed Extension. The detailed methodology including equations is

presented within Technical Appendix 18.1, and is broadly in line with the

methodology presented in both the IEMA guidance and the government

guidance document ‘Energy recovery for residual waste – A carbon based

modelling approach’.

Transport

18.4.31 The following indirect carbon emissions have been included within the scope of

the assessment:

• carbon emissions associated with the transport of waste to the Proposed

Extension;

• carbon emissions associated with the transport of reagents to the

Proposed Extension;


• carbon emissions associated with the transport of residues from the

Proposed Extension; and

• carbon emissions associated with the transport of waste to landfill.

18.4.32 The carbon burden is determined by calculating the total number of loads

required and multiplying it by the transport distance to generate an annual one-

way vehicle distance. This is multiplied by the respective empty and full carbon

dioxide factor for HGVs to determine the overall burden of transport. Full details

of the assumptions are provided in Appendix 18.1.

Sensitivity Analysis

18.4.33 A sensitivity analysis has been undertaken to assess the impact on the results

when changing the electricity grid displacement factor and the landfill gas

capture rate.

18.4.34 There is some debate over the type of power that would be displaced by the

electricity generated by the Proposed Extension and so lower figures have been

considered for the grid displacement factor, which would only be relevant if the

Proposed Extension were to displace other renewable sources of electricity.

This type of assessment is in line with IEMA (2017) guidance which states that

it is often necessary to assess multiple GHG factors for the same activity,

particularly when the assessment is studying a life cycle with a long time period.

The guidance specifically refers to this in the context of a reduction in

greenhouse gas emissions associated with the national electricity grid.

18.4.35 The DEFRA (2014) report ‘Review of Landfill Emissions Modelling’ states that

the collection efficiency for large, modern landfill sites was estimated to be 68%

and the collection efficiency for the UK as a whole was estimated to be 52%.

There have been suggestions in other guidance that a conservative figure of

75% should be used. For example, the DEFRA report ‘Energy recovery for

residual waste: A carbon based modelling approach’ (2014) describes how the

government have historically used an assumption of 75% capture, e.g. for

Greenhouse Gas Inventory and other purposes. However this is described as

‘optimistic’ and it is stated that a figure between 50-60% might be more realistic

with the assumption that this will improve with newer technology over time.


Therefore, a range of landfill gas capture rates have been assessed in the

sensitivity analysis.

Baseline

18.5.1 The quantity of GHG emissions associated with the baseline landfill scenario

has been calculated in accordance with the stated methodology.

18.5.2 The results are presented in Table 18.6.

Table 18.6: Emissions from landfill gas

Item Units Value

Biogenic carbon tonnes 43,632

Total DDOC content (biogenic carbon not sequestered – degradable) tonnes 21,816

Methane in LFG, of which: tonnes 16,580

-Methane captured tonnes 11,275

-Methane oxidised in landfill cap tonnes 531

-Methane released to atmosphere directly tonnes 4,775

Methane leakage through gas engines tonnes 154

Total methane released to atmosphere tonnes 4,929

CO2e released to atmosphere tCO2e 123,221

18.5.3 The amount of CO2e emissions offset through electricity generation for the

landfill comparator are presented in Table 18.7 below.

Table 18.7: Offset of CO2e emissions from the Export of Electricity from Landfill

Gas Engines

Item Units Value

Methane captured, of which: tonnes 11,275

-Methane Flared tonnes 1,025

-Methane leakage through gas engines tonnes 154

-Methane used in gas engines tonnes 10,096

Fuel input to gas engines GJ 474,503

Power generated MWh 47,450

Total CO2e offset through grid displacement tCO2e 16,608

18.5.4 The emissions associated with the transport of waste to and from a landfill is

presented in Table 18.8.


Table 18.8: Indirect transport Emissions from Landfill

Parameter Nominal tonnage

(tpa)

Number of loads

required (p.a.)

One-way distance

(km)

One-way total

distance per year (km)

Total emissions

(CO2e)

Waste to landfill 300,000 16,667 48 800,016 1,363

Assessment of Effects

Operation Phase Effects

18.6.1 The detailed carbon assessment is included in Appendix 18.1. A summary of

the key results from the assessment are provided in the following table.

Table 18.15: Summary of Key Results from the Assessment

Parameter Emissions (CO2e)

Releases from landfill gas 123,221

Transport of waste and outputs to landfill 1,363

Offset of grid electricity from landfill gas engines -16,608

Total baseline emissions 107,976

Transport of waste to and outputs from the Proposed Extension 134,249

Offset of grid electricity with Proposed Extension generation 3,247

Emissions from the Proposed Extension -80,360

Total Proposed Extension Emissions 57,136

Net benefit of Proposed Extension 50,840

18.6.2 As shown, there will be a net carbon benefit of approximately 50,840 tCO2e per

annum for the Proposed Extension when compared to the baseline. Over the

expected lifetime of the Proposed Extension (assumed to be 25 years for the

purposes of this assessment), the net carbon benefit of the Proposed Extension

will be approximately 1,271,000 tCO2e compared to the baseline. Therefore, it

can be concluded that the Proposed Extension will have a significant positive

effect to reducing carbon emissions when compared to the baseline.

18.6.3 Another way to express the benefit of the Proposed Extension is to consider the

additional power generated by the Proposed Extension as compared to the

landfill counterfactual and calculate the effective net carbon emissions per MWh


of additional electricity exported. The effective carbon intensity is calculated to

be 0.0709 tCO2e/MWh.

Sensitivity Analysis

18.6.4 A sensitivity analysis has been undertaken to take into account future baseline

scenarios. A summary is presented in the following table.

Table 18.14: Net benefit of Proposed Extension from sensitivity analysis (t CO2e)

Grid displacement

factor (tCO2e/MWh)

Landfill gas capture rate

75% 68% 60% 52%

0.35 23,413 50,840 82,186 113,532

0.32 18,095 45,376 76,554 107,733

0.28 11,004 38,090 69,045 100,000

18.6.5 As shown in Table 18.14, there will be a net carbon benefit (and a significant

positive effect) in all cases assessed.

Summary

18.7.1 The Proposed Extension will have a net carbon benefit when compared to the

baseline. In addition, when comparing a range of sensitivities to account for

varying grid displacement factors there remains a net benefit associated with

the development of the Proposed Extension. Therefore, it can be concluded that

the Proposed Extension will have a significant positive effect to reducing

carbon emissions when compared to the baseline.

Documents

CHAPTER 18.0 CLIMATE CHANGE€¦ · climate change assessments for planning and permitting purposes for a wide range of developments including Energy from Waste facilities across