Transitional arrangements

The remaining provisions of the IWA will come into force on 15 December 2025. Section 146 of this act makes it clear that if you want to use the DNS regime, you need to have submitted your article 5 notification (under the DNS (Procedure) Order 2016) to Planning and Environment Decisions Wales (PEDW) and, under the Regulations, this means before 15 December 2026. Probably best not to leave this to the last minute in case there are any issues with the acceptance of the notice (e.g. with invoicing or queries over the development description).

If you want to use the SIP regime and you have carried out pre-application consultation (PAC) for a project 12 months before the Regulations have come into force you will not need to repeat the PAC process. This is on the proviso that the consultation and publicity requirements set out in the Infrastructure Consent (Pre-Application and Application Procedure and Transitional Provisions) (Wales) Regulations 2025 have been complied with as if they were in force at the time of the consultation. In theory you could go to PC now and follow these requirements to get a head start. Whilst the PAC requirements are broadly similar to those of the PAC process under the DNS regime, there are some important differences that need to be carefully considered. We strongly recommend that developers entering PAC and wanting to use the SIP regime familiarise themselves with the relevant requirements to ensure time and resources allocated to PAC are not wasted. Statutory consultees are obliged to provide pre-application advice (to be paid for of course) but if they do not do so in the timescales provided there is no penalty that imposed against them. There are reporting requirements, however, so Natural Resources Wales and LPAs have to tell Welsh ministers that they are not meeting the statutory requirements. It is not clear what the Welsh ministers will do with that information. You need to notify the Welsh ministers formally if you want to use the SIP regime (similar to the requirement in the DNS regime). Under the SIP regime an application has to be made within 18 months of the Welsh ministers accepting the SIP notification. This can be extended by 56 days where a statutory consultee has concerns about the project to such an extent that it would object to the application and the applicant seeks to address this concern. The Welsh ministers have listed to the consultation feedback and made this period longer and added in some flex. PAC needs to be undertaken within the 18 month period, although the Infrastructure Consent (Pre-Application and Application Procedure and Transitional Provisions) (Wales) Regulations 2025 provide that within three months of the acceptance of the notification by the Welsh ministers, an applicant has to publicise the draft application documents on a website. This includes all of the application documents e.g. the ES, application documents and plans, details of the consultation events undertaken or proposed to be undertaken, updates and timescales, details of changes made to the proposal and a consents statement. Whilst a draft ICO is not specified we assume one will be needed as it is likely to be referred to in the application form.

New to the list of application documents: for onshore energy projects you will need to include a statement identifying who will be responsible for designing and building the grid connection. For offshore energy projects detail of the proposed grid route and method of installation needs to be provided. There are more extensive requirements for rail projects, particularly in terms of plans ad sections, following a similar line to those required for Transport and Works Act Orders.

The examining authority (ExA) has to decide whether to accept an application within 6 weeks of receiving it. This can be extended to a further 14 days 'or such period as the Welsh Minsters determine'. Some significant discretion in that tailpiece. The ExA has to determine the examination procedure within 28 days after the six week representation period has closed. This can be by way of written representations, hearings or a public inquiry (though note that the likelihood of an inquiry being used is incredibly slim – Welsh government does not like inquiries and no DNS project to date that we are aware of has been allowed the use of the inquiry process despite it being requested on a number of DNS projects). The ExA must hold an open-floor hearing when requested by one or more persons, providing the request is valid (i.e. it complies with the requirements set out in the Welsh ministers’ notice of valid application). An open-floor hearing will not be held if the request concerns representations that are vexatious or those which relate to the merits of a particular planning policy, or which relate to compensation for compulsory acquisition of land or a right over land. It is interesting to note the Welsh government initially proposed that the trigger for holding an open-floor hearing would be upon the request of at least 10 interested parties. This trigger has been significantly reduced, which could be said to be a direct reflection of the importance placed on community engagement. Looks like every SIP will be having an open floor hearing in that case! It's also interesting to see inter-party questioning may be permitted at hearings. DNS hearings tend to all flow through the Inspector although inevitably parties discuss issues and this feels like a sensible way to get to the heart of an issue (although Inspectors will be wary of cross-examination in a hearing setting). Hearings may be recorded. They tend not to be at the moment for DNS schemes. Recordings are helpful, especially when making post-hearing representations or negotiating further points with statutory consultees, and particularly if you are considering a legal challenge. Applications can be varied at any time during the Examination. This is a helpful change given the only window under the DNS regime is within two weeks of the end of the five week representation period (which we have always considered to be too limited, especially where issues can arise further along in the Examination process).

A big entrant to the SIP regime is the concept of the section 22 direction. Whilst developers can request that a scheme falls into the SIP regime, most of the attention has been on the Welsh Minsters’ unilateral use of this power to essentially call projects into the regime, at any stage. The September 2024 consultation explained that this provision was primarily intended for use by developers of medium energy output projects which could potentially have significant environmental impacts (the example of a 45MW solar farm was given, which could potentially have significant environmental effects) or those of new/novel technology where the application of a capacity threshold is not appropriate (e.g. hydrogen). The full list of these Optional SIP projects is now set out in Schedule 1 to the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations 2025. Interestingly, rather than a fixed sub-50MW category for all energy projects (which is a category in its own right it should be noted), for solar and onshore wind the optional SIP threshold is 35MW to 50WM (construction and extension). Other optional SIPs include overhead lines at 132kv under 2km in length, underground lines of at least 2km in length, hydrogen development and substations. The inclusion of underground lines over 2km is a surprise, as is including substations. This begs the question: what about battery storage? Well, we’ve asked the Welsh government’s Infrastructure Team to clarify this and we will update you. On first blush, given the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations 2025 refer to the definition of a generating station in s.64 of the Electricity Act 1989, it would appear that battery storage falls out of the SIP regime because battery storage does not generate electricity per se. Battery storage not being included in the SIP regime is not what the September Consultation proposed (10MW + was to be an optional SIP), nor is the Welsh government’s response to the Consultation clear. The Planning Act 2008 and the DNS Specified Criteria and Secondary Consents Regulations 2016 both carve out battery storage from the NSIP and DNS regimes (by implication without such an exclusion battery storage would be classed as a generating station). Moreover, battery storage is included in the Electricity Act generation licence regime via changes brought in by the Energy Act in 2023. Without clarity on this point, we assume battery storage is excluded from the SIP regime entirely, albeit if it is included that means sub-50MW battery storage is an optional SIP, and everything above 50MW is a SIP. Welsh ministers must make a decision on whether to give a direction within 29 days of it being requested (unless further information is required, in which case an additional period of 29 days is permitted). We’re not sure why 29 days has been chosen. It is worth noting that anyone can request a s.22 direction, providing the requirements of the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations are complied with. In terms of being brought into the SIP regime, an optional project could very well be in unclear territory in terms of what aspects of the SIP regime may need to be adhered to. For example, if you are part way through a Town and Country Planning Act planning application for a 40MW solar farm, perhaps about to be considered by committee and a s.22 direction is issued, what aspect of the SIP regime need to be followed? Thankfully, discretion abound, the Welsh Minsters can direct that certain provisions of the Infrastructure (Wales) Act 2024 do not apply – this includes the requirement to carry out PAC and the requirement for an ICO. There is a lot of flexibility in Regulation 8 of the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations and our expectation is that Welsh government will supplement how this provision is to be used in practice in their Guidance document. Cross-border projects: the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations allow the SIP regime to be turned off for cross border projects (albeit the Welsh Minsters have previously stated that it would be wholly exceptional for them to do this).

What new regulations have been introduced under the Planning in Wales Infrastructure (Wales) Act 2024?

On 18 June 2025 the Welsh government laid down five statutory instruments to support the delivery of Wales’s new Significant Infrastructure Project (SIP) consenting regime under the Infrastructure (Wales) Act 2024 (IWA).

These Regulations flesh out the outline in the act, giving more detail on each stage of an application for an infrastructure consenting order (ICO). They also cover relevant fees, compulsory acquisition requirements and the approach to optional SIPs (or schemes directed into the SIP regime by the Welsh ministers).

The Fees Regulations and the Miscellaneous Provisions Regulations are subject to final sign-off by the Senedd, in which case, they are subject to change (and some of the provisions may indeed need changing and require industry comment). Also, two further sets of Regulations are anticipated to be published in due course relating to changing, revoking and challenging ICOs.

In short, much of the content in the Regulations follows closely the detail in the IWA, which closed in December 2024. On 24 June, the Welsh government issued its response to this Consultation and the draft Regulations reflect their final position on how they want the regime to operate. A big gap in all of this is the supporting Guidance document which the Welsh government has explained will clarify a number of the outstanding questions around how the Regulations will be applied in practice.

Those familiar with the Developments of National Significance (DNS) regime will know how broadly the DNS Regulations have been drafted (particularly in terms of the Welsh ministers’ and Inspectors’ ability to deviate from the seemingly fixed processes and timescales). The SIP Regulations are no different. What is clear is that there is a lot of flexibility built into the Regulations in which case users of the system need to be careful because there are practical realities (e.g. resourcing in Local Planning Authorities (LPAs) and statutory consultees) which will mean the discretion to deviate from the process set in the Regulations will be used more frequently.

In this article we highlight the five regulations that will support the SIP consenting regime and outline the key points and timescales.

The regulations that will support the SIP consenting regime

Key provisions of the Regulations

Pre-application

If you want to use the SIP regime and you have carried out pre-application consultation (PAC) for a project 12 months before the Regulations have come into force you will not need to repeat the PAC process. This is on the proviso that the consultation and publicity requirements set out in the Infrastructure Consent (Pre-Application and Application Procedure and Transitional Provisions) (Wales) Regulations 2025 have been complied with as if they were in force at the time of the consultation. In theory you could go to PC now and follow these requirements to get a head start.
Whilst the PAC requirements are broadly similar to those of the PAC process under the DNS regime, there are some important differences that need to be carefully considered. We strongly recommend that developers entering PAC and wanting to use the SIP regime familiarise themselves with the relevant requirements to ensure time and resources allocated to PAC are not wasted.
Statutory consultees are obliged to provide pre-application advice (to be paid for of course) but if they do not do so in the timescales provided there is no penalty that imposed against them. There are reporting requirements, however, so Natural Resources Wales and LPAs have to tell Welsh ministers that they are not meeting the statutory requirements. It is not clear what the Welsh ministers will do with that information.
You need to notify the Welsh ministers formally if you want to use the SIP regime (similar to the requirement in the DNS regime). Under the SIP regime an application has to be made within 18 months of the Welsh ministers accepting the SIP notification. This can be extended by 56 days where a statutory consultee has concerns about the project to such an extent that it would object to the application and the applicant seeks to address this concern. The Welsh ministers have listed to the consultation feedback and made this period longer and added in some flex.
PAC needs to be undertaken within the 18 month period, although the Infrastructure Consent (Pre-Application and Application Procedure and Transitional Provisions) (Wales) Regulations 2025 provide that within three months of the acceptance of the notification by the Welsh ministers, an applicant has to publicise the draft application documents on a website. This includes all of the application documents e.g. the ES, application documents and plans, details of the consultation events undertaken or proposed to be undertaken, updates and timescales, details of changes made to the proposal and a consents statement. Whilst a draft ICO is not specified we assume one will be needed as it is likely to be referred to in the application form.

Examination

The examining authority (ExA) has to decide whether to accept an application within 6 weeks of receiving it. This can be extended to a further 14 days 'or such period as the Welsh Minsters determine'. Some significant discretion in that tailpiece.
The ExA has to determine the examination procedure within 28 days after the six week representation period has closed. This can be by way of written representations, hearings or a public inquiry (though note that the likelihood of an inquiry being used is incredibly slim – Welsh government does not like inquiries and no DNS project to date that we are aware of has been allowed the use of the inquiry process despite it being requested on a number of DNS projects).
The ExA must hold an open-floor hearing when requested by one or more persons, providing the request is valid (i.e. it complies with the requirements set out in the Welsh ministers’ notice of valid application). An open-floor hearing will not be held if the request concerns representations that are vexatious or those which relate to the merits of a particular planning policy, or which relate to compensation for compulsory acquisition of land or a right over land.
It is interesting to note the Welsh government initially proposed that the trigger for holding an open-floor hearing would be upon the request of at least 10 interested parties. This trigger has been significantly reduced, which could be said to be a direct reflection of the importance placed on community engagement. Looks like every SIP will be having an open floor hearing in that case!
It's also interesting to see inter-party questioning may be permitted at hearings. DNS hearings tend to all flow through the Inspector although inevitably parties discuss issues and this feels like a sensible way to get to the heart of an issue (although Inspectors will be wary of cross-examination in a hearing setting).
Hearings may be recorded. They tend not to be at the moment for DNS schemes. Recordings are helpful, especially when making post-hearing representations or negotiating further points with statutory consultees, and particularly if you are considering a legal challenge.
Applications can be varied at any time during the Examination. This is a helpful change given the only window under the DNS regime is within two weeks of the end of the five week representation period (which we have always considered to be too limited, especially where issues can arise further along in the Examination process).

Optional SIPs

A big entrant to the SIP regime is the concept of the section 22 direction. Whilst developers can request that a scheme falls into the SIP regime, most of the attention has been on the Welsh Minsters’ unilateral use of this power to essentially call projects into the regime, at any stage.
The September 2024 consultation explained that this provision was primarily intended for use by developers of medium energy output projects which could potentially have significant environmental impacts (the example of a 45MW solar farm was given, which could potentially have significant environmental effects) or those of new/novel technology where the application of a capacity threshold is not appropriate (e.g. hydrogen).
The full list of these Optional SIP projects is now set out in Schedule 1 to the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations 2025. Interestingly, rather than a fixed sub-50MW category for all energy projects (which is a category in its own right it should be noted), for solar and onshore wind the optional SIP threshold is 35MW to 50WM (construction and extension).
Other optional SIPs include overhead lines at 132kv under 2km in length, underground lines of at least 2km in length, hydrogen development and substations. The inclusion of underground lines over 2km is a surprise, as is including substations.
This begs the question: what about battery storage? Well, we’ve asked the Welsh government’s Infrastructure Team to clarify this and we will update you. On first blush, given the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations 2025 refer to the definition of a generating station in s.64 of the Electricity Act 1989, it would appear that battery storage falls out of the SIP regime because battery storage does not generate electricity per se. Battery storage not being included in the SIP regime is not what the September Consultation proposed (10MW + was to be an optional SIP), nor is the Welsh government’s response to the Consultation clear. The Planning Act 2008 and the DNS Specified Criteria and Secondary Consents Regulations 2016 both carve out battery storage from the NSIP and DNS regimes (by implication without such an exclusion battery storage would be classed as a generating station). Moreover, battery storage is included in the Electricity Act generation licence regime via changes brought in by the Energy Act in 2023. Without clarity on this point, we assume battery storage is excluded from the SIP regime entirely, albeit if it is included that means sub-50MW battery storage is an optional SIP, and everything above 50MW is a SIP.
Welsh ministers must make a decision on whether to give a direction within 29 days of it being requested (unless further information is required, in which case an additional period of 29 days is permitted). We’re not sure why 29 days has been chosen.
It is worth noting that anyone can request a s.22 direction, providing the requirements of the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations are complied with.
In terms of being brought into the SIP regime, an optional project could very well be in unclear territory in terms of what aspects of the SIP regime may need to be adhered to. For example, if you are part way through a Town and Country Planning Act planning application for a 40MW solar farm, perhaps about to be considered by committee and a s.22 direction is issued, what aspect of the SIP regime need to be followed? Thankfully, discretion abound, the Welsh Minsters can direct that certain provisions of the Infrastructure (Wales) Act 2024 do not apply – this includes the requirement to carry out PAC and the requirement for an ICO. There is a lot of flexibility in Regulation 8 of the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations and our expectation is that Welsh government will supplement how this provision is to be used in practice in their Guidance document.
Cross-border projects: the Infrastructure Consent (Miscellaneous Provisions) (Wales) Regulations allow the SIP regime to be turned off for cross border projects (albeit the Welsh Minsters have previously stated that it would be wholly exceptional for them to do this).

Commentary

The IWA and this suite of Regulations are the future for developing infrastructure in Wales. Those familiar with the DNS and NSIP regimes will recognise a lot of similarities of both in the SIP regime. Reading the Regulations, it feels like the Welsh government have followed their own mantra of including the ‘best of both’.

As we have said before, the regime offers a significant number of new powers which can be used to unlock sites, not just powers of compulsory acquisition and access/surveying powers but also incorporating a raft of other consents in an ICO or disapplying other legislative requirements to facilitate the delivery of a project. The Regulations give the Welsh ministers and the ExA a lot of discretion in terms of process, procedure and timescales which may beg the question around certainty of the decision making process. However, one thing that is missing from the regime’s full picture is the supporting Guidance (as noted above). We would hope for further clarity in this document to address how the Welsh government envisages certain powers being used in practice.

The shift from a regime focussed on full planning permission (for DNS projects) compared to one offering a significant amount of flexibility with defined limits of deviation, as well as use of the Rochdale envelope concept (available to SIP projects) will need a mind-set shift for a number of practitioners and developers operating in Wales but ultimately it should put developers in that rare position of having both control and flexibility over the delivery of their projects.

Get in touch with our planning and infrastructure team if you would like to discuss the changes in greater detail and what they mean for you. We will also be hosting a seminar to offer further insight into the new procedure, so keep an eye on our website for more details to be announced soon.

Key contacts

View all