Heat in buildings strategy: strategic environmental assessment

6. Findings of the Assessment

6.1 Introduction

6.1.1 A staged approach to the assessment has been undertaken as set out in the Assessment methodology (See Section 4.3). Early assessment work included a review of relevant SEA environmental reports to identify known likely environmental effects. See Appendix A for further details.

6.2 What are the Key Proposals

A proposed new 2045 vision and wide supportive energy efficiency and heat decarbonisation outcomes

6.2.1 To support the pathway to zero emissions for homes and buildings the draft Strategy introduces a new 2045 vision and recognises a wider set of high level outcomes that will benefit Scotland’s people and places (See Section 1 for further details). These outcomes, aligned with the National Performance Framework, will guide decision making and support the development of a holistic, people centred approach to the transition to net zero. The vision and outcomes draw together a range of Scottish Government policies and proposals relevant to energy efficiency and heat decarbonisation such as those that focus on climate change, energy and housing.

Setting a new heat target

6.2.2 The draft Strategy sets out the intention, through a finalised Strategy, to set a new heat target, the purpose of which is to help monitor and track progress in delivering the deployment pathway for reducing emissions in buildings, as set out in the Update to the Climate Change Plan. The target will also help drive emissions reductions commensurate with net zero and interim climate change targets.

6.2.3 The draft Strategy recognises that those measures ready for deployment (energy efficiency measures, heat pumps and heat networks) have an important strategic role now. It further recognises the potential future role that hydrogen and bioenergy could play in the longer term.

6.3 What are the environmental issues of relevance

6.3.1 Key environmental issues of relevance relate to the SEA topics of climatic factors, air, population and human health, material assets, landscape and cultural and historic heritage.

6.3.2 Key issues for climatic factors include greenhouse gas emissions from a range of sources, with energy supply and use of homes and buildings contributing to emissions. Observed climate change trends (such as wetter winters, drier summers and extreme weather events) are likely to intensify in the future and this can negatively impact on energy infrastructure (such as through flooding). Climate change can also give rise to indirect effects arising from mitigation and adaptation measures. For example energy efficiency and heat decarbonisation of Scotland’s homes and buildings contributes to meeting statutory climate change targets. However, individual technologies can have negative impacts such as localised visual effects on cultural and historic heritage, changes in landscape and land use, and impacts on biodiversity, water and air quality, amongst others. Climate change has also been identified as a primary pressure on many of the SEA topic areas.

6.3.3 Key issues for population and human health include challenging weather, poor energy efficiency and reduced heating options (especially in rural areas) which can contribute to making fuel bills unaffordable, resulting in fuel poverty. The potential risks and benefits of climate change on population and human health will not be evenly spread. For example, areas of dense urban development will be more at risk from surface water flooding and summer heat stress. In addition the effects to human health from climate change may have the greatest impact on vulnerable people. Negative health impacts are likely to be disproportionately severe in areas of high deprivation because of the reduced ability of individuals and communities in these areas to prepare, respond and recover.

6.3.4 Key issues for air include emissions from a number of sectors leading to air pollution, with air quality contributing to a number of health problems. Air quality and GHG emissions are intrinsically linked as they both arise from broadly the same sources. Measures that seek to reduce emissions from buildings such as from improved energy efficiency and heat decarbonisation, have the potential to broadly contribute to improved air quality.

6.3.5 Key issues for material assets include those associated with development and infrastructure and pressure on land use. Energy efficiency and heat decarbonisation as a means to support emission reductions from Scotland’s homes and buildings will require new or expanding infrastructure facilities at a range of scales^[96]. Changes in land use required to meet wider climate change targets could also have environmental effects.

6.3.6 Key issues for landscape include the potential for direct and indirect impacts associated with the development and deployment of energy efficiency measures and heat technologies and their associated infrastructure. For example, land use change and intensification associated with incremental and on-going development such as infrastructure and energy projects.

6.3.7 Key issues for cultural heritage include development which is a key pressure on the historic environment and cultural heritage, both directly in terms of damage to known and unknown features, and possible impacts on setting such as changes to the fabric of buildings.

6.4 What are the likely significant environmental effects of key proposals

A proposed new 2045 vision and wide supportive energy efficiency and heat decarbonisation outcomes

6.4.1 The proposed new vision and high level outcomes provide a high level framework that draws together existing Scottish Government policies and proposals relating to energy efficiency and heat decarbonisation of homes and buildings. When taken together with existing PPS this can contribute to significant positive effects for climatic factors, population and human health, air and material assets.

6.4.2 For example, where the vision and outcomes focus on sustainable sourcing of fuels consistent with net zero targets and support for flexible and stable energy networks for example, these can contribute to broad environmental benefits for climatic factors, air, population and human health and material assets. Where outcomes focus on reducing fuel poverty and sustainable jobs for example, these can contribute to broad environmental benefits for population and human health. Where outcomes recognise existing biodiversity targets this can also contribute to broad environmental benefits for biodiversity, soil and water.

Strategically important energy efficiency measures and heat technologies in the short term

6.4.3 In particular, it is considered likely that a focus on strategically important energy efficiency measures and heat technologies ready for deployment will broadly and cumulatively contribute to significant positive effects for climatic factors, air, population and human health and material assets in the short term.

6.4.4 For example, cumulative positive effects for climatic factors are considered likely as a result of reducing GHG emissions associated with broad support for measures that reduce the overall demand for heat. Associated air quality improvements are also considered likely due to linkages between sources of GHG emissions and air pollutants such as particulate matter.

6.4.5 Cumulative positive effects for population and human health are also considered likely where a focus is given to reducing fuel poverty. For example, fabric first measures can help to reduce the cost of achieving thermal comfort. Individual heat pumps can also be highly effective in most buildings when they are combined with appropriate energy efficiency measures. Real consumer benefits can also arise where the draft Strategy supports more affordable and locally available supplies of heat associated with heat networks.

6.4.6 Cumulative positive effects for material assets are also considered likely as a result of benefits associated with a greater diversity in technologies and future-proofing energy supply as a means to support greater resilience to the effects of climate change.

6.4.7 Mixed/uncertain secondary effects on a range of SEA topics could also occur as a result of the take up of strategically important energy efficiency measures and heat technologies ready for deployment. Effects could range from permanent to temporary and significance would be dependent on a number of factors, including scale, siting and design. These are discussed further below.

Energy efficiency measures

6.4.8 Localised mixed/uncertain secondary effects on a range of SEA topics could occur as a result of the deployment of energy efficiency measures. Any potential adverse effects are considered likely to be largely localised because they relate to the fabric of individual buildings.

6.4.9 For example, the installation and operation of efficiency measures could in principle give rise to some localised negative effects on biodiversity (as a result of works undertaken to roof cavities (i.e. insulation) which may hold bat roosts), on cultural and historic heritage (such as directly from visual impacts on settings), and on landscapes (such as directly from visual impacts on settings). Localised negative effects on population and human health and air quality in the short term could also occur (such as from construction activities and development work) but these are considered likely to be temporary in nature. Localised positive effects on population and human health are also considered likely (as a result of reducing the cost of achieving thermal comfort).

6.4.10 Any potential adverse impacts are considered likely to be mitigated by existing mechanisms such as the planning system as well as environmental guidance and on-site management measures. Local mitigation is discussed further in Section 7.

Heat pumps and heat networks

6.4.11 Localised mixed/uncertain secondary effects on a range of SEA topics could occur as a result of the deployment of heat pumps and heat networks, the significance of which would be largely dependent on the scale as well as location with respect to sensitive human, natural and cultural receptors.

6.4.12 Previous SEA work recognises that the installation of district heating network infrastructure such as pipes has the potential for localised environmental effects including short term negative effects on material assets from new development activities. Localised negative effects on population and human health could also arise such as, through noise linked to the operation of heat pumps. Potential localised negative effects on landscape and cultural and historic heritage could also occur as a result of at scale changes to infrastructure necessary for deployment. For example, the installation of an individual air source heat pump would require an external unit, which would require a place outside the home where it can be fitted to a wall or placed on the ground, including space around it to ensure the flow of air. The size of the unit could vary greatly depending on the building’s heat demand and the local characteristics.

6.4.13 Localised positive effects on material assets and population and human health could also occur from support for more affordable and locally available supplies of heat associated with heat networks. Effects could be maximised where individual heat pumps are combined with appropriate energy efficiency measures which makes them highly effective in most buildings.

6.4.14 Any potential adverse impacts are considered likely to be mitigated by existing mechanisms such as the planning system as well as environmental guidance and on-site management measures and these, as well as potential strategic mitigation opportunities, are discussed further in Section 7.

Strategically important heat technologies with the potential to play a role in the longer term

6.4.15 Heat technologies identified as playing a potential future role in heating homes and buildings (principally hydrogen) could also potentially broadly and cumulatively contribute to significant positive effects for climatic factors, air, population and human health and material assets identified above in the longer term.

6.4.16 Low carbon or ‘Green’ Hydrogen is recognised by the draft Strategy as having a potential role as a source of energy for heating buildings as a future alternative to natural gas. Noting constraints in the near-term availability of hydrogen, coupled with a need to establish the standards and safe systems for its use, repurpose the gas network and replace household appliances, decarbonised gas is unlikely to play a large part in reducing emissions before 2030.

6.4.17 The deployment of blue (or low-carbon) hydrogen (where aligned with CCS systems) and green hydrogen at scale has the potential lead to significant positive effects for climatic factors as well as associated positive effects on air and population and human health.

6.4.18 Previous SEA work recognises that proposals which encourage the uptake of low carbon technologies such as CCS and hydrogen may result in development which could have adverse effects on topics such as landscape and cultural heritage. However, significance will depend on a range of factors including scale of development, and the quality and sensitivity of receiving environments.

6.4.19 There is also potential for uncertain effects on material assets in the longer term. This is considered possible as a result of ‘at scale’ deployment of hydrogen as a replacement for natural gas which could potentially result in a need for new or upgraded infrastructure (such as CCS and pipework) which could in turn impact on sensitive human, natural and cultural receptors. The significance of any future potential effects however would be largely dependent on the scale of deployment, and associated infrastructure requirements.

6.4.20 Adverse localised effects on a number of SEA topics such as population and human health, soil, water, air and biodiversity, as a consequence of construction and infrastructure improvement works could also occur but it is recognised that these effects are likely to be temporary in nature.

6.4.21 Bioenergy is recognised in the draft Strategy as likely to have a limited role in supporting heat decarbonisation of homes and buildings where other technologies are not appropriate. The draft Strategy also notes that the volume of bioenergy likely to be available in the short term is limited by constraints on primary biomass resources, and the higher value of some bio-resources in decarbonising other sectors.

6.4.22 Previous SEA work recognises that an increased uptake of biomass could cumulatively raise some challenges regarding material assets (Land Use) such as forestry expansion and agriculture. This is because visual effects on landscapes and cultural heritage can arise from the uptake of technologies at both national and local scale including through changes in land use.

6.4.23 Any potential environmental effects associated with future development and deployment of hydrogen and/or bioenergy will need to be considered in due course as part of the development of proposals to support their introduction and these will be considered against the requirements of the 2005 Act. Existing mitigation measures as well as opportunities for strategic mitigation are discussed in Section 7.

Setting a new heat target

6.4.24 The setting of a new heat target which has the delivery of net-zero objectives at its heart, focuses on heat in buildings, and is compatible with statutory fuel poverty targets can lead to significant positive effects for climatic factors, through its support for delivering the deployment pathway for reducing emissions in buildings as set out in the update to the Climate Change Plan.

6.4.25 Linked to this, there is potential for associated significant positive effects for air quality (as emissions and air pollutants often originate from the same source), as well as associated benefits for population and human health. Previous SEA work highlights that further benefits for population and human health are also likely to arise from improved security of energy supply and reduced heat demand, which may also have benefits for general health and wellbeing. The above benefits are likely to be experienced to a greater extent where support is focused towards those living in deprived areas.

6.4.26 Significant positive effects for material assets are also considered likely from a focus on a mixed technology or blended pathway. This is because a focus on strategically important technologies that are ready for deployment (energy efficiency measures, heat pumps and heat networks) in the short term, as well as recognition of a potential role for hydrogen (and, in a limited way, bioenergy) in the long term, can enable the flexible and stable operation of the energy network at a national scale.

Ambition

6.4.27 We acknowledge that, in setting a new heat target there are differing levels of ambition in delivering net zero objectives. At a minimum the setting of a new heat target would need to support the delivery and the deployment pathway for reducing emissions in buildings as set out in the update to the Climate Change Plan.

6.4.28 A more ambitious target could support reductions in GHG emissions over a shorter timeframe, for example as a result of a higher rate of deployment of strategically important energy efficiency measures and heat technologies, with benefits arising for climatic factors. Associated positive environmental effects including for factors such as air quality population and human health would also be realised more quickly.

6.4.29 A more ambitious target could also have the potential for adverse environmental effects. In particular, as a result of a more ambitious target any potential associated greater levels of deployment of heat technologies could necessitate the need for new and upgraded infrastructure which could potentially realise adverse environmental effects on Material assets as well as other SEA topics in the shorter term. Taking into account the strategic nature of the draft Strategy, and the level of inherent uncertainties, including for example the longer-run energy mix, it is not possible to be precise at this time.

6.5 Do the key proposals address key environmental issues identified?

6.5.1 Taken together, and when considered in the round, the proposals set out in the draft Strategy are likely to contribute to addressing the key environmental issues identified. Significant reductions in GHG emissions associated with Scotland’s homes and buildings are likely as well as associated benefits for air and population and human health (including through measures which help mitigate fuel poverty). Further, a blended or mixed technology pathway can contribute to diversifying energy supply and can support the use of local energy systems, with the potential to improve the resilience of energy networks (including to the impacts of climate change).

6.5.2 The assessment recognises that there is potential for direct and indirect impacts on cultural and historic heritage and landscape associated with the development and deployment of energy efficiency measures and heat technologies and their associated infrastructure now and in the future. It is considered that existing mitigation measures as well as strategic mitigation opportunities can help ensure that potential adverse effects are avoided and positive effects enhanced. Further opportunities for mitigation and enhancement are included in Section 7.