NPF4 planning guidance: policy 2 - climate mitigation and adaptation

4. Determining planning applications: climate mitigation

4.0.1 This section sets out advice to applicants on how to approach climate mitigation, including the steps that can be taken to inform and support their application, as well as to planning authorities who will wish to take this information into account when applying balanced planning judgement in decision-making.

4.1 Lifecycle greenhouse gas emissions

4.1.1 NPF4 Policy 2 sets out a need for development proposals to demonstrate that:

‘lifecycle greenhouse gas emissions have been minimised as far as possible.’

4.1.2 Lifecycle greenhouse gas emissions refer to the total amount of greenhouse gases released into the atmosphere over the entire life of a development. This includes all stages, from resource extraction to end-of-life disposal.

4.1.3 Understanding the likely sources of lifecycle GHG emissions of a development, and what control the applicant has over these, is critical to enable their minimisation. This process should be initiated at the earliest design stages as:

• the ability to effect change to achieve GHG emissions reduction for a project reduces over time as the project progresses^[8].
• early considerations can support evaluation of the full range of opportunities for delivering the best outcomes for emission reductions, and may help avoid the cost of later ‘retrofit’ or re-design.
• it can create co-benefits and promote innovation, improving the sustainability and resilience of our built environment, whilst also helping to identify lower cost solutions. There is a strong alignment of carbon cost and financial cost, where a more efficient use of resources should lead to a reduction in both^[9].

4.2 Managing lifecycle GHG emissions: a proportionate approach

4.2.1 The decision-maker (usually the planning authority) will determine what information is needed to accompany a planning application. It is in both the applicant and planning authority’s interest to establish requirements as early as possible to ensure the right level of quality information is sought and provided timeously. In each case, the consideration will be whether enough information has been provided to make a decision on the proposed development.

4.2.2 Factors that may have a bearing on whether information is required to assess a proposal against Policy 2, and if so whether this should be qualitative or quantitative include:

4.2.3 The emissions reduction opportunity. Some proposals may offer options for emission reductions that are relatively minor in isolation, or relate to matters which are not themselves planning considerations or which cannot reasonably be secured through the planning system.

4.2.4 Uncertainty or lack of detail. For instance an application for planning permission in principle can be used to establish the acceptability of a proposed development in principle without the level of technical detail that accompanies an application for detailed permission. Whilst this lack of detail does not itself preclude consideration of emissions reductions, the need for flexibility in the future evolution of the detailed project proposal will need consideration. Where any assumptions are made for assessment purposes, these should be clearly stated. It may also be appropriate to require certain information at a later stage through conditions, provided the relevant tests set out in Planning Circular 4/1998 are met. It should be noted that particular statutory obligations will also apply to any EIA development.

4.2.5 Assumed mitigation / other regulatory controls or standards. Where any relevant standards or obligations apply under other regulatory regimes, for example Scottish building regulations, these can be taken into account as ‘assumed mitigation’.

4.2.6 The importance of quantified data vs qualitative data for decision-making. Does the planning authority consider that quantified data on the project’s GHG emissions will better inform decision-making? In some instances, a qualitative approach will be sufficient or appropriate for setting out what measures have been taken to minimise emissions for some or all parts of the project lifecycle.

4.3 Which development types to assess

4.3.1 Taking the above factors into account, the following development types are unlikely to require assessment of lifecycle greenhouse gases:

• changes of use (including retrofit)
• householder development or equivalent scale of other development types
• proposals for less than 10 residential units and non-residential buildings less than 1000m2 floorspace.

4.3.2 For these development types, the applicant may still wish to provide a short statement summarising the overall approach taken to minimising emissions and / or provide such information set out in section 4.5 below as is considered relevant to the proposal.

4.3.3 For proposals not falling within paragraph 4.3.1 above the planning authority can apply judgement on whether an assessment is required and, if so, the level of assessment appropriate to the circumstances of the proposal, for instance whether it is qualitative, quantitative or a combination. The following guidance supports this process.

4.4 Environmental Impact Assessment

4.4.1 Where relevant, Environmental Impact Assessment (EIA) is a means of drawing together, in a systematic way, an assessment of a project’s likely significant environmental effects on a range of factors, including on climate.

4.4.2 Schedule 4, paragraph 5 of the EIA Regulations requires:

"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) and the vulnerability of the project to climate change"

4.4.3 The approach and resources set out in this guidance, particularly in Section 4.5, can both help inform and be informed by the preparation of a project’s EIA. The Institute of Environmental Management and Assessment (IEMA) has published guidance EIA^[10] on assessing GHG emissions within the EIA process.

4.5 Four Step Assessment

4.5.1 The applicant assesses and minimises lifecycle greenhouse gas emissions of their development proposal. The following guidance is informed by the research^[11] undertaken on the approaches currently in use across the built environment sector.

4.5.2 The emissions assessment can follow the four steps as set out below:

Step 1. Identify: primary project emissions and removals

This includes a basic review of the main expected carbon emissions and removals at each stage of the project’s lifecycle.

Step 2. Clarify control: understanding what emissions and removals can be controlled or influenced by the applicant

This step considers what control the applicant has over individual or all elements of the development that give rise to GHG emissions during its lifecycle. Taking those elements that can be controlled through to Step 3.

Step 3. Manage GHG emissions: minimising emissions and maximising removals

Working through those elements of the development that are in the control of the applicant, to identify GHG emissions and how these can be minimised.

Step 4. Report: Reporting on outcome and monitoring (where relevant)

Reporting on what steps have been taken to minimise project lifecycle GHG emissions as far as possible.

Step 1. Identify: primary project emissions and removals

4.5.3 Consideration of lifecycle GHG emissions associated with a development proposal requires an understanding of the primary emission sources and removals. Emissions generated throughout a project’s lifecycle include those associated with:

• the extraction and manufacture of materials used in construction,
• the emissions of construction activities themselves,
• those arising from the maintenance, operation and use of a building or asset,
• associated transportation of materials/ goods and people to and from the site throughout its lifetime
• the impact the activity or outputs of the development have beyond its boundary, through to its eventual end of life, decommissioning, demolition or re-use.

The lifecycle of a development includes the following stages^[12]:

• A: Before Use
• B: Operation, Use and Maintenance
• C: End of life

4.5.4 Additionally, a development may have influence over emissions or removal of GHGs that lay beyond the development boundary. This can be referred to as part D of the lifecycle:

• D: Influence of the project on emissions or removals beyond the development proposal boundary.

4.5.5 As a guide, the emission sources and removals associated with each lifecycle stage of a development may include, but are not limited to, the following:

A: Before Use (including pre-construction, design and construction stages)

• Location and siting: Both the location of the development and the siting and layout of built elements within the development boundary can lead to emissions and removals. For example these could arise from transport emissions associated with the operation or use of the site, the preparation of the site, and / or the removal or integration of natural and semi-natural habitat as a consequence of the development.
• Design and materials used in construction. The embodied emissions in the materials, products and components to be used in the development. These emissions include those caused by the extraction of the necessary raw materials, as well as the processing and manufacture of those materials into products, their transportation, and assembly.
• Construction activities: Emissions from energy needed for construction processes and activities, including the fuel in construction machinery.
• Land use change: this includes the potential loss of natural carbon stores in excavated soils or cleared habitat being lost to the atmosphere, in addition to any subsequent emissions from the decomposition of organic material.

B: Operation or Use (including ongoing maintenance)

• Use of the development: this relates to any emissions associated with the energy demand of the development. For example in buildings this includes running the technology used to heat, cool and ventilate it.
• Maintenance of the development: Emissions from maintenance, repair, and replacement activities to manage and service components of the development.
• Emissions from land use management, including landscaping or environmental enhancement programmes, which may lead to emissions removals/ sequestration whilst recognising the complexity and novelty of the science in this regard.

C: End of use (including decommissioning if relevant)

• Emissions attributed to this stage include those arising from the processes and activities linked to materials recovery from the building or infrastructure asset once it is no longer in use. It includes material recovery for reuse by another project, input into a recycling scheme, or disposal as waste (e.g. landfill, incineration, composting).

D: Influence of the project on emissions or removals beyond the development proposal boundary

• This stage considers the potential emissions associated with outputs from the entire project lifecycle including from the construction, maintenance, repair and replacement/ refurbishment and the end of life materials and their disposal.
• Additionally this stage considers the emissions sources and sinks that exist beyond the development proposals boundary, such as the changes it causes in transport demand or product and service outputs.

Step 2: Clarify control: understanding what emissions and removals are within the control of the applicant

4.5.6 For an applicant to successfully minimise lifecycle GHG emissions it follows that they will need control over some or all of the projects’ emissions or removals and the planning authority will also wish to have confidence the desired outcome can be secured with reasonable certainty. Taking time to understand what can reasonably be controlled will help in prioritising those elements for assessment and should inform considerations on the scope and level of detail of GHG emissions information necessary to accompany a planning application. It will also inform decisions on whether to take a quantitative or qualitative approach.

4.5.7 The level of control over emissions across the range of development types will vary considerably. Key factors that could affect control include the ability to engage with and influence some or all of the supply chain; and the ability to specify materials and products that will be used in the development. This latter point may include sector specific collaborations focused on reducing emissions from key components or technologies within their industry. Examples are given for the renewable energy generation sector below.

4.5.8 The greater the control for any or all elements of a project’s emissions and removal activities, the more opportunity there is for the applicant to minimise them.

Step 3. Manage GHG emissions: minimising emissions and maximising removals

4.5.9 This step includes reference to regulatory and voluntary standards and GHG assessment methods; the tools available to calculate project emissions; and an approach to minimising those emissions.

4.5.10 Standards and assessment methods: It is a long-established principle that the planning system does not seek to duplicate other regulatory controls. Where relevant regulatory standards apply to a development these can be considered as assumed mitigation, for example:

• energy standards within Scottish building regulations^[13] require effective measures for the conservation of fuel and power to be incorporated into the design of new buildings, including good levels of insulation, high efficiency (zero direct emission) heating solutions (exceptions permitting) and effective use of on-site generation of heat and power, to deliver buildings which require very little energy and produce zero/minimal operational emissions at the point of use.

4.5.11 In addition there are industry standards and assessment methods which seek to address lifecycle GHG emissions. In some sectors these are required, whereas for others they can be applied voluntarily. Example standards and assessment methodologies that can be used include:

• Net-Zero Public Sector Buildings Standard^[14]: this can be applied to new and retrofit buildings and includes elements covering inclusive economy/ embodied carbon/ operational energy/ other whole life carbon/ indoor environment quality/ environmental aspects.
• PAS 2080 (2023) Carbon Management in Buildings and Infrastructure^[15]: a best practice standard for managing carbon in buildings and infrastructure across the entire lifecycle of the project. The application of this standard is mandated by some industry sectors, including the renewables sector as set out below.
• UK Net Zero Carbon Buildings Standard: A Pilot Version of the Standard enables industry to demonstrate a built asset is in line with climate targets.
• RICS whole life carbon assessment: this standard allows for consistent and accurate carbon measurement in buildings and infrastructure throughout the built environment life cycle.
• EIA fits into this category, with best practice approach set out in IEMA guidance.
• Transport Scotland set out that current roads construction contracts include the preparation of a Carbon Management Plan in line with PAS 2080. The Transport Scotland Roads Projects Carbon Tool allows users to estimate the carbon emissions associated with infrastructure and simple project designs and to report the carbon footprint of projects based on data collected during construction.

4.5.12 Additionally, best practice sector or industry collaborations focused on minimising project emissions may be relevant to individual development proposals. Examples of these in the renewables sector are given below in Section 4.6.

4.5.13 Calculating emissions: Emissions data inventories which may be relevant when calculating emissions include the following freely available databases. These include industry benchmarks and tools to quantify embodied emissions of materials such as bricks, cement, wood and tiles and emissions from operation of machinery and vehicles:

• DESNZ Greenhouse Gas Reporting: Conversion Factors^[16]: The Department for Energy Security and Net Zero (DESNZ) conversion factors are a set of conversion factors that can be used by UK and international organisations to calculate carbon emissions across a wide range of activities
• The Inventory of Carbon and Energy Database^[17]: The Inventory of Carbon and Energy (ICE) database is a comprehensive resource developed to quantify the embodied energy and carbon emissions associated with various materials and processes throughout their life cycles. This information can be used to compare the emissions : impacts of different materials and processes.
• The Built Environment Carbon Database^[18] (BECD): The BECD collects and supplies both product-level and entity-level data to the industry through its own portal, and through interacting with existing databases and software solutions. The BECD can be used to estimate the carbon emissions of a building or infrastructure project, and to compare the carbon impact of different materials and construction methods.

4.5.14 In addition to the above freely available sources of emissions data, there are a range of tools that help to calculate total carbon emissions. This includes the process of multiplying the emissions factors with the activity data (i.e. the quantity of materials) to calculate the carbon impact of the identified emissions sources. Models also allow for analysis and interrogation of the calculations as well as the presentation of scenarios to find optimal project design solutions. Tools are set out in the research^[19] that informs this guidance and include for example the One Click Planetary^[20] and OneClick LCA tools, the former includes benchmarks for embodied carbon and the latter offering the ability to compare different project design scenarios to identify where emissions can be minimised.

4.5.15 For some development types, there may also be sector or topic specific tools. An example includes:

• Natural England: Carbon Storage and Sequestration by Habitat 2021. This report reviews the scientific evidence base relating to carbon storage and sequestration by semi-natural habitats, in relation to their condition and/or management. It provides those working in land management, conservation and policy with relevant information to underpin decisions relating to carbon in semi-natural habitats.

4.5.16 Minimising emissions: A mitigation hierarchy can help identify measures to minimise project emissions. Such hierarchies are commonly used in a range of contexts and they set out actions that can be taken in an order that descends from highest to lowest, whether that be priority, effectiveness or in this case, greatest potential for minimising GHG emissions. Importantly, the ability to reduce carbon in projects reduces as the process approaches the final design and delivery of the project^[21].

4.5.17 For those priority elements that have been identified as being ‘in control’, the following prompts help identify actions to reduce their emissions. This approach draws upon IEMA^[22] guidance and is set against the actions of the PAS 2080 carbon mitigation hierarchy of ‘Avoid, Switch and Improve’:

Avoid:

• Consider the potential to reuse or retrofit existing structures as this makes use of those materials and structures already on site. This avoids the need for new construction materials that contain significant embodied carbon, in addition to the emissions from transportation and construction processes to ‘build new’.

Switch:

• Potential to switch new for old, which can mean specifying the use of recycled materials over new, such as the material content of aggregates or metals. Many currently available standard products already include a degree of recycled content.
• Explore use of low carbon innovations, which can include switching to lower carbon technologies, lower embodied carbon materials and applying whole systems net-zero standards.

Improve:

• As a complementary strategy to switching, each design measure in turn can be considered for improvement. Also, opportunities to sequester carbon through habitat enhancements can be employed to offset carbon emissions.
• Consider identifying and adopting solutions and techniques that improve the use of resources and design life of a development. This can include applying a circular economy approach to reduce, reuse or recycle materials in line with the waste hierarchy and using nature-based solutions.
• Consider what construction techniques can be employed to improve efficiencies and use techniques (e.g. during construction and operation) that reduce resource consumption and associated GHG emissions over the life cycle of the project, where relevant.

Step 4. Report: reporting on outcome and monitoring (where relevant)

4.5.18 The applicant can prepare a report setting out a clear description of what actions have or will be taken to reduce emissions. The following prompts are designed to assist in preparing such a report:

• Brief description of the development proposal.
• Confirmation of those primary lifecycle emissions or removals that are in the control of the applicant and justification for why others may not be. This may include a summary of emissions broken down by lifecycle stage as follows:
  • Before use
  • Operation or use
  • End of use
  • Influence of project beyond development boundary
• Reporting can be qualitative, quantitative or a combination of both. Where relevant, reference should be made to any carbon management standard that has/ will be achieved for the proposal. Alternatively, if the approach has focused on a single or certain specific project element, then an explanation of the approach (including the tools and methods used) that has been taken to minimise emissions for these elements.

Where mitigation measures are required, planning authorities will need to consider carefully how such measures are to be secured. Where planning conditions or obligations are to be used, the relevant tests set out in Planning Circular 4/1998 and Planning Circular 3/2012 must be met. For something to be taken into account as a material consideration it must be relevant to planning and relate to the development proposed by the particular application under consideration.

4.6 Renewable electricity generation and mitigation

4.6.1 To realise our climate change ambitions, we need to transform the way Scotland generates, transports and uses energy. NPF4 Policy 11 (energy) says, when considering the impacts of proposals, significant weight will be placed on the contribution of the proposal to renewable energy generation targets and on greenhouse gas emissions reduction targets.

4.6.2 For lifecycle GHG assessments relating to renewable energy development including enabling works, such as grid transmission and distribution infrastructure, the following sector specific examples of tools and collaborations may be relevant:

• Sector specific collaborations include:
  • Zero Steel^[23] initiative comprising renewable energy generation and other sectors seeking to tackle emissions from steel production.
  • UK ROCCIT (Reduction of Capital Carbon in Infrastructure and transmission): a group which has published a methodology, product calculator and carbon asset database for suppliers to use in measuring and reporting the embodied carbon in their assets.
• Sector standards:
  • Ofgem’s environmental reporting guidance^[24] expects that network operators improve whole life carbon reporting and align with the PAS2080 standard for all major infrastructure projects across the transmission and distribution networks

4.7 Peatland and climate mitigation

4.7.1 Reversing degradation of peatland and securing peatland restoration is central to climate mitigation and adaptation.

4.7.2 Scotland has over 2 million hectares of peatland, equating to approximately one third of its land area, and our peatlands are of national and global significance. In good condition, peatlands provide multiple benefits: capturing and storing carbon, supporting nature, reducing flood risk, cleaning the water that feeds our burns and lochs, and providing places for leisure that can support health and wellbeing. However, around 75% of our peatlands are degraded through drainage, extraction, overgrazing, burning, afforestation and development. Degraded peat offers fewer benefits and becomes a net emitter of greenhouse gases and currently accounts for around 15% of Scotland’s total emissions.

4.7.3 The following tools and references can be used to support the consideration of peatland and its incorporation in a lifecycle GHG assessment:

• The Scottish Government’s Peatland Carbon Calculator: The Carbon Calculator for wind farm developments on Scottish peatlands was developed to support decision making by calculating the carbon impact of wind farm proposals and comparing those with the carbon savings attributable to the wind farm. The calculator has been subject to a recent review^[25] undertaken by Climate XChange (CxC) but currently remains the best available means by which carbon calculations can be provided in a consistent and comparable format, until such a time as there is an alternative or replacement of the calculator.
• Reuse of excavated peat on wind farm development sites, CxC research project: This project, which at the time of writing is expected to publish soon, includes a rapid evidence assessment and wide stakeholder engagement to understand current use of excavated peat on wind farm developments, and to develop a hierarchy of best practice based on environmental outcomes.