Permitted Development Rights review - phase 3: consultation

5. Electricity Undertakings

5.1 Overview

5.1.1 Linked to the focus on domestic and non-domestic renewables, this Chapter considers the PDR available for electricity undertakings included at class 40 of the GDPO. This recognises that our electricity networks will need to be significantly upgraded and expanded in the coming years to support new renewable energy generation and to meet growing demands for electricity associated with the transition to low carbon technologies.

5.1.2 This follows a recent UK Government Call for Evidence on Land Rights and Consents for Electricity Network Infrastructure (August 2022) which sought views on amending the equivalent PDR that apply to electricity licence holders in England. This Call for Evidence placed particular focus on existing PDR for the installation or replacement of substation infrastructure with a capacity less than 29 cubic metres. Views were sought on whether this 29 cubic metre threshold remains fit for purpose. Because any changes to license holder PDR by the UK Government would only apply in England, we are keen to explore the case for updating the equivalent provisions in Scotland.

5.2 Class 40 (Electricity Undertakings)

Current PDR for electricity undertakings

5.2.1 Class 40 (Electricity Undertakings) of the GPDO provides PDR for certain development undertaken by statutory undertakers for the generation, transmission or supply of electricity. Statutory undertakers include licence holders within the meaning of section 6(1) of the Electricity Act 1989. These cover generation licence holders, transmission licence holders, distribution licence holders, supply licence holders, interconnector licence holders and smart meter communication licence holders.

5.2.2 Class 40 PDR cover a range of development needed for the upgrading and expansion of electricity networks, including electric lines (section 5.3), substations (section 5.4), communications lines (section 5.5), site investigation works (section 5.6) and certain development on operational land (section 5.8). These PDR have not been substantively amended for some time and there may be opportunities to update them to reflect our changing energy system.

Context for change: electricity undertakings

5.2.3 We note that the electricity undertakings permitted at class 40 are described as works for the 'generation, transmission, or supply of electricity'. This description does not fully reflect the range of licenced undertakings listed at section 6 of the Electricity Act 1989, however. Some scope therefore exists to clarify this description so that it is explicit that these PDR relate to works for 'smart meter communications' and the 'distribution' and 'interconnection' of electricity alongside its 'generation, transmission, or supply.'

5.2.4 We also consider that, in addition to reviewing the PDR available to statutory undertakers for the installation or replacement of substation infrastructure, there are opportunities to review the wider PDR available to statutory undertakers to cover changes in technology and to support forthcoming programmes for the upgrading and expansion of electricity networks.

Proposals: electricity undertakings

5.2.5 In light of the considerations above, we propose to amend class 40 to clarify that the PDR can be used by statutory undertakers for purposes of 'smart meter communications' and the 'distribution' and 'interconnection' of electricity alongside its 'generation, transmission, or supply.'

Question 20: Do you agree that class 40 PDR should be amended to clarify that they can be applied by statutory undertakers for the purposes of 'smart meter communications' and the 'distribution' and 'interconnection' of electricity as well as its 'generation', 'transmission' and 'supply'?

Please add any comment in support of your answer

5.3 Electric Lines

5.3.1 Electric lines transport electricity across various distances to areas of demand. They include electrical cables that can be installed underground or overground suspended on steel or aluminium towers or wooden poles^[11].

Current PDR for electric lines

5.3.2 PDR at class 40(1)(a) allow undertakers to install or replace electric lines above or below ground provided that there is no requirement to apply to the Scottish Ministers for consent under section 37 of the Electricity Act 1989.

5.3.3 These PDR therefore apply to all below ground electric lines and any above ground electric line that is listed amongst the exemptions identified at section 37(2) of the Electricity Act 1989 or within the Overhead Lines (Exemption) (Scotland) Regulations 2013. Class 40(1)(a) also allows undertakers to construct any shafts or tunnels and substations (see section 5.4) reasonably necessary in connection with an electric line.

5.3.4 Works for the installation and replacement of electric lines permitted under Class 40(1)(a) are subject to conditions. These set out that any conditions relating to the height, design or position of an electric line should apply when it is replaced. They also require the removal of electric lines and the reinstatement of land following temporary diversions.

Proposals: electric lines

5.3.5 We do not propose amending the PDR available at class 40(1)(a) to statutory undertakers for the installation or replacement of electric lines. There may, however, be some opportunity to allow additional smaller scale electric lines to be permitted under the PDR at class 40(1)(a) as part of a broader review of consenting under section 37 of the Electricity Act 1989 and the exemptions included within the Overhead Lines (Exemption) (Scotland) Regulations 2013. This work is outside the scope of the phased review of PDR, however, and we will consider separately whether is appropriate to extend the scope of the 2013 Regulations.

5.4 Substation Infrastructure

5.4.1 Substations convert electricity into different voltages and regulate the flow of current. Substations contain electrical equipment for these purposes (transformers, switches etc.) which can be housed in chambers made of metal, brick or plastic. The size, appearance and configuration of substations can vary significantly. Substations are fenced off from the public and feature yellow and black triangular signs that carry electrocution warnings.

Current PDR for substation infrastructure

5.4.2 Class 40(1)(a) allows electricity undertakers to install or replace substation infrastructure reasonably necessary in connection with an electric line. This substation infrastructure includes feeder pillars, service pillars, transforming stations, switching stations and chambers. These PDR do not apply to substation infrastructure housed in a chamber with a capacity greater than 29 cubic metres, however.

Context for change: substation infrastructure

5.4.3 Additional substation infrastructure will be required in areas of demand as electricity networks are upgraded and extended to support the deployment of low carbon technologies such as heat pumps and EV chargers.

5.4.4 We understand that the current 29 cubic metre limitation on the PDR available to statutory undertakers for substation infrastructure does not allow for the installation of certain standard designs employed across the network. Additionally, we understand that a larger development footprint can allow for safer access for the maintenance of substations. There may also be a requirement to replace and enlarge existing substation infrastructure to create additional capacity within electricity networks as demand increases.

5.4.5 It is recognised that new or replacement substations which are larger than the current 29 cubic metre threshold could have additional impacts on amenity. As such, we consider that it may be appropriate to add limitations relating to the size and/or siting of larger substation infrastructure.

Proposals: substation infrastructure

5.4.6 In light of the above considerations, we propose to amend class 40 by:

• Increasing the maximum size threshold from 29 cubic metres to 45 cubic metres.
• Providing that a new/replacement substation installed under class 40:
  • May not exceed a 3m height limit.
  • May not be within 5m of a dwelling if it exceeds 29 cubic metres.

Question 21: Do you agree with the proposed amendments to the provisions of class 40 PDR which relate to new or replacement substations?

Please add any comment in support of your answer

5.5 Communications Lines

5.5.1 Telecommunications lines are incorporated into electricity networks to ensure electrical safety and to monitor the operation of the network. They allow communication between substations and end points so that faults can be anticipated, and circuits can be switched off if necessary. They comprise wirelines or fibre-optic cables used to carry information. Proposals for overhead electric lines often incorporate communications technologies and carry data in addition to electricity. Separate communications infrastructure can, however, sometimes be required.

5.5.2 When not incorporated into an overhead electric line, communications lines are typically installed in a duct below ground or on wooden poles above ground. Inspection chambers are also needed for the maintenance of below ground communications lines and the covers for these chambers are often visible above ground level.

Current PDR for electric communications lines

5.5.3 Class 40(1)(b) allows statutory undertakers to install or replace any telecommunications line which connects any part of an electric line to any electrical plant or building. It also covers any supports needed for communications lines. These PDR do not apply in a National Scenic Area or a Site of Special Scientific Interest. Restrictions also apply to electronic communications lines greater than 1,000m in length or supported on a structure greater than 15 metres in height.

Context for change: electric communications lines

5.5.4 Electronic communications lines provide essential communication links for the operation of electricity networks. Given that PDR are already available to statutory undertakers for the installation or replacement of below ground electric lines and above ground electric lines and chambers not requiring section 37 consent, there may be some opportunity to create efficiencies by extending the PDR for linked electronic communications lines.

Proposals: electric communications lines

5.5.5 We propose to allow for the replacement of communications lines in those designated areas (National Scenic Areas or Sites of Special Scientific Interest) where the PDR does not currently apply. This would be subject to a condition ensuring that the height, design or position of the replacement communications line reflects that of the existing communications line. As currently, the installation of new communications lines in those areas would not be covered by PDR.

5.5.6 We are also considering extending these PDR to allow statutory undertakers to install or replace communications lines which are longer than 1,000m - and would welcome thoughts on what (if any) alternative threshold might be appropriate.

Question 22: Do you agree with the proposal to allow the replacement of communications lines in National Scenic Areas and Sites of Special Scientific Interest under class 40 PDR provided that the design, height or position of the replacement line matches the original?

Please add any comment in support of your answer

Question 23: Do you have any thoughts on the potential to provide for the installation or replacement of communications lines of a greater length than 1,000m under class 40? If so, do you have a view on an appropriate alternative threshold?

Please add any comment in support of your answer

5.6 Site Investigation Works

5.6.1 Site investigation works are required to collect information on, assess and report potential hazards or constraints associated with a site used for electricity undertakings.

Current PDR for site investigation works

5.6.2 Class 40(1)(c) allows statutory undertakers to sink boreholes to ascertain the nature of the subsoil, and to install plant or machinery reasonably necessary in connection with such boreholes. These works are subject to a condition at class 40(3)(c) that on the completion of the development or at the end of a period of six months from the beginning of that development (whichever is sooner) any such plant or machinery shall be removed, and the land shall be restored as soon as reasonably practicable. The land must be restored to its condition before the installation took place, or to such condition as may have been agreed in writing between the planning authority and the developer.

Context for change: site investigation works

5.6.3 The nature of investigation works needed to assess sites for electricity undertakings has evolved beyond the sinking of boreholes to ascertain the nature of the subsoil. In addition to the sinking of boreholes to undertake soil testing, a range of methods and equipment may be used to evaluate the suitability of sites. These include the sinking of rotary boreholes to investigate the mineral stability of the site, peat-probing, the excavation of trial pits and gas and water ground monitoring. We are giving consideration to amending the PDR to reflect this.

Proposals: site investigation works

5.6.4 In line with the considerations above, we propose to extend the type of site investigation works that statutory undertakers can carry out under class 40 PDR. This would involve broadening the scope of works to include additional intrusive survey and site investigation works and associated temporary plant, including: rotary boreholes, peat-probing, excavation of trial pits and gas and water ground monitoring.

5.6.5 Any additional site investigation works permitted would be subject to the condition at class 40(3)(c) that any plant or machinery shall be removed, and the land shall be restored as soon as reasonably practicable upon completion of the development (or within six months from the beginning of the development). We are, nevertheless, interested in respondents' views on whether potential adverse effects linked to site investigation works should be mitigated through restrictions on certain works in designated areas, or through limitations on the scale of trial pits to be excavated.

Question 24: Do you agree with the proposal to extend the range of site investigation works that can be carried out under class 40?

Please add any comment in support of your answer

Question 25: Do you consider that there are any designated areas where PDR for certain site investigation works should be restricted? Should there be any limitations on the scale of certain intrusive site investigation works permitted, for example, the size of trial pits?

Please add any comment in support of your answer

5.7 Fences, Gates, Walls and Other Means of Enclosures

5.7.1 Facilities for electricity undertakings will often require fencing-off from the public as a safety measure. Fencing can also reduce the visual impact of electricity network infrastructure and allow for better relationships with surrounding development.

Existing PDR for gates, fences, walls and other enclosures

5.7.2 Class 7 of the GPDO relates to the erection, construction, maintenance, improvement or alteration of a gate, fence, wall or other means of enclosure without the need to apply for planning permission. These PDR are not specific to particular parties and are applicable to anyone: this includes, but is not limited to, electricity undertakers.

5.7.3 Class 7 PDR do not apply where the height of the enclosure, after carrying out the development, would exceed 1m above ground level when constructed within 20m of a road. They also do not apply for the construction or erection of any enclosure which would exceed 2m in height.

5.7.4 Further restrictions on these PDR apply where the height of any enclosure would, as a result of works for its maintenance, improvement or alteration, exceed its former height or would exceed the height thresholds identified above. These PDR also do not apply where the proposed enclosure would involve development within the curtilage of a listed building.

Context for change: gates, fences, walls and other enclosures

5.7.5 The Electricity Safety, Quality and Continuity Regulations 2002 place a number of requirements on the delivery of electricity network infrastructure to ensure public safety. Part III of these Regulations specify that substations are enclosed where necessary to prevent, so far as is reasonably practicable, danger or unauthorised access. These regulations also specify that any part of an electricity substation, which is open to the air and contains live equipment, which is not encased, is enclosed behind a fence or wall not less than 2.4m in height.

5.7.6 Given the above, we are minded to introduce specific PDR within class 40 for the erection or construction of fences, gates, walls and other enclosures linked to electricity undertakings. These PDR would not be subject to the height restrictions included at class 7, reflecting the specific public safety considerations associated with electricity undertakings.

Proposals: gates, fences, walls and other enclosures

5.7.7 It is proposed to introduce specific PDR enabling statutory undertakers to erect, construct, maintain, improve or alter a gate, fence, wall or other means of enclosure linked to electricity undertakings. These would be linked to class 40 and so not available to other parties.

5.7.8 These amended provisions would not be subject to the height restrictions that apply to class 7 and, instead, would be subject to a general height limit of 3m. Additionally, it should be noted that there is a general limitation at section 3(5)(a) of the GDPO on development that creates an obstruction to the view of persons using any road used by vehicular traffic would apply.

Question 26: Do you agree with the proposed introduction of specific PDR enabling electricity undertakers to erect, construct, maintain or improve gates, fences, walls or other means of enclosure up to 3m in height?

Please add any comment in support of your answer

5.8 Development on Operational Land

5.8.1 As demand for electricity from renewable sources increases, existing renewable energy generation and electricity network facilities will need to be upgraded to ensure resilience and enable the generation of additional capacity. This is likely to require the development of additional apparatus and the incorporation of new technologies on operational land in use for electricity undertakings.

Existing PDR for development on operational land (electricity undertakers)

5.8.2 Class 40(1)(d-f) allows electricity undertakers to carry out certain developments on operational land. In this context, 'operational land' is defined at sections 215 and 216 of the Town and Country Planning (Scotland) Act 1997.

5.8.3 Class 40(1)(d-f) permits a range of development on operational land including the extension or alteration of buildings and the erection of new buildings for the protection of plant or machinery.

5.8.4 These PDR are subject to certain limitations and conditions. Most notably, Class 40(3)(d) requires that prior notification is given to the relevant planning authority, who may then require that prior approval is obtained from them on the details of the siting, design and external appearance of new buildings erected on operational land for the protection or plant or machinery. This is in addition to a 15m height limitation on such development.

Context for change: development on operational land (electricity undertakers)

5.8.5 'Operational land' is defined at sections 215 and 216 of the Town and Country Planning (Scotland) Act 1997. Any proposal to review the definition of 'operational land' included within the Town and Country Planning (Scotland) Act 1997 would be outside the scope of the phased review of PDR, however.

5.8.6 The requirement for prior notification of and approval from the relevant local planning authority on the siting, design and external appearance of new buildings for housing plant/machinery to be developed on operational land, has been identified as an additional process for applicants and planning authorities which does not necessarily improve outcomes given the existing use of land for electricity undertakings. We are therefore considering the removal of this prior notification and approval mechanism from class 40.

Proposals: development on operational land (electricity undertakers)

5.8.7 We propose to remove the requirement for prior notification and approval from planning authorities on the siting, design and external appearance of new buildings for housing plant/machinery permitted on operational land for electricity undertakings.

Question 27: Do you agree with the proposed removal of prior notification and approval requirements that apply to certain works under class 40 PDR?

Please add any comment in support of your answer

Question 28: Please provide any further views you may have on the proposals in this section on the PDR associated with electricity undertakings.

Please add any comment in support of your answer