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Grid Supply Point Embedded Generation Capacity Heatmap

Click on the substations to see more information about them
Key Red Connection Green Yellow Amber Infrastructure Not a GSP 400 kV circuit 275 kV circuit
Connah's Quay Middleton Sutton Bridge Penn Pyle Iver Drax Fleet Abham Grain Hurst Wylfa Blyth Sundon Legacy Stanah Pentir Kirkby Hutton Walham Pelham Harker Elland Keadby Margam Warley Norton Cowley Bolney Rassau Minety Exeter Fawley Didcot Cottam Seabank Taunton Kitwell Kemsley Whitson Laleham Walpole Grendon Padiham Rugeley Deeside Rowdown Norwich Main Heysham Enderby Ninfield Lovedean Bramford Bredbury Nursling Drakelow Pitsmoor Neepsend Aldwarke Sizewell Melksham Thornton Offerton Aberthaw Rochdale Hartmoor Pembroke Landulph Rye House Sellindge Tynemouth Wymondley Feckenham Poppleton Cilfynydd Axminster Bridgwater Bicker Fen Staythorpe Mannington Ffestiniog Spennymoor Penwortham Osbaldwick Shrewsbury Willington Chickerell Cellarhead Eaton Socon Creyke Beck Trawsfynydd Grimsby West Chesterfield Burwell Main Alverdiscott Langage Indian Queens Hinkley Point Dinorwig Rainhill Capenhurst Frodsham Washway Farm South Manchester Carrington Daines Fiddlers Ferry Macclesfield Kearsley Whitegate Stalybridge Dungeness Canterbury North Braintree Waltham Cross Swansea North Baglan Bay Cardiff East Tremorfa Alpha Steel Upper Boat Uskmouth Imperial Park Iron Acton Marchwood Botley Wood Bramley Culham Quernmore Coventry Nechells Willenhall Bustleholm Hams Hall Berkswell Oldbury Bishops Wood Ironbridge Ocker Hill Spalding North Patford Bridge Ferrybridge Eggborough Thorpe Marsh Thurcroft Brinsworth High Marnham Templeborough West Melton Norton Lees Jordanthorpe Sheffield City Winco Bank Stocksbridge West Burton Saltend North Saltend South South Humber Bank Bradford West Kirkstall Skelton Grange Monk Fryston Killingholme Humber Refinery East Claydon Rayleigh Main Coryton Singlewell Kingsnorth Littlebrook Wimbledon Beddington Chessington West Weybridge St Johns Wood Ealing Willesden Watford Elstree Tottenham Redbridge Barking Leighton Buzzard Amersham Main Tilbury City Rd New Cross Hackney Brimsdown South Shields West Boldon Hawthorne Pit Hartlepool Tod Point Grangetown Greystones Lackenby Stella West Fourstones West Ham Northfleet East West Thurrock Stoke Bardolph Bushbury Bodelwyddan Knaresborough Saltholme Hedon Ratcliffe on Soar Cleve Hill Mill Hill Rocksavage Necton

Categories of sites

Green Connection
There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.


Amber Connection
Connections in this area are, under onerous operating conditions, approaching a limit at the GSP. National Grid will either require the DNO and the developers to an arrange a flexible operating arrangement (e.g. ANM) to prevent GSP limits being breached in which case National Grid will not restrict connections at the GSP, or GSP investment will be required which is likely to delay to connection and a developer may be asked to both fund and secure works in order to solve the issue on a Attributable basis. Most commonly the DNO and developers agree the flexible arrangement.


Yellow Connection
For a timely connection the developer must agree with the DNO to flex their output as required (e.g. by ANM scheme), as, under onerous conditions, the GSP limits would be breached without that flexibility. (Note if a developer requires a firm connection GSP investment will be required which is likely to delay to connection and a developer may be asked to both fund and secure works in order to solve the issue on a Attributable basis.)


Red Connection
There are currently significant limitations on connections due to restrictions on assets at this GSP. There is likely to be a delay to a connection and the developer may be asked to both fund and secure works in order to solve the issue on a Attributable basis.


Green Infrastructure
There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.


Amber Infrastructure
Connections in this area are approaching a limit at the GSP. National Grid may invest in more capacity at this GSP, or look to create an operability scheme to flex generation under onerous conditions, depending on which solution is most economic and efficient. If investment is chosen the developer will be asked to secure that investment on an Attributable basis, the securities will cease to apply when a developer connects and so does not directly fund the investment, but cancelled projects will be liable for the investment they have triggered and not used.


Yellow Infrastructure
Connections will be asked to join an operability scheme and be flexible in their output, as, under onerous conditions, the GSP limits would be breached without that flexibility.


Red Infrastructure
There are currently significant limitations on connections due to restrictions on assets at this GSP. There is likely to be a delay to a connection and the developer may be asked to secure works in order to solve the issue on a Attributable basis. The securities will cease to apply when a developer connects and so does not directly fund the investment, but cancelled projects will be liable for the investment they have triggered and not used.

Abham 400kV

There are currently fault level restrictions on assets interconnected with this GSP. However, there are temporary measures to address this fault level issue whilst a permanent solution is delivered. Any connection prior to the permanent solution being delivered would be subject to constraining under certain conditions. There are no thermal restrictions; tertiaries of both the SGTs at this substation available for the connection of generation.

Aberthaw 275kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Amber. No fault level issues. There are three SGTs, two of which have spare tertiary connections. There is one spare bay at 275 kV and two are spare at 132 kV.

Aldwarke 275kV

Not a GSP.

Alpha Steel 33kV

Not a GSP.

Alverdiscott 400kV

Generation output would subject to constraining as instructed by the ANM scheme due to existing thermal restrictions. Given that Alverdiscott and Indian Queens GSPs are interconnected, ANM scheme also resticts embedded generation connected at Indian Queens. There are no spare bays. The 2 SGTs' tertiaries are not available for the connection of generation.

Amersham Main 400kV

Site has no thermal or fault level issues.

Axminster 400kV

The transmission assets (Fleet - Lovedean) in proximity to this site are above their thermal limits and thus any additional generation at this site would require transmission reinforcement works. There are no spare bays. The 2 SGTs both have tertiaries that are available for the connection of generation.

Axminster 132kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development.

Baglan Bay 275kV

Not a GSP.

Barking 275kV

Site has no thermal or fault level issues.

Barking 400kV

Site has no thermal or fault level issues.

Beddington 400kV

Site has no thermal or fault level issues.

Berkswell 275kV

The Red status has been assigned for battery connections only and the site has a Green status for all other generation technology types. The site currently has no spare bays. The site consists of three supergrid transformers. All supergrid transformers have available tertiary connections.

Bicker Fenn

The site is approaching thermal limits of the existing supergrid transformers and new generation is likely to trigger a reinforcement. The site currently has no spare bays. The site consists of two supergrid transformers. Both supergrid transformers have available tertiary connections.

Birkenhead 275kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of three supergrid transformers. Two of them have available tertiary connections.

Bishops Wood 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Blyth 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Bodelwyddan 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP. National Grid will either require the DNO and the developers to an arrange a flexible operating arrangement (e.g. ANM) to prevent GSP limits being breached. The site currently has no spare bays, no supergrid tramsformer.

Bolney 400kV

Regional voltage collapse limit. Active Network Management under development.

Botley Wood 400kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development.

Braintree 400kV

Site has no thermal or fault level issues.

Bradford West 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Bredbury 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Bramford 400kV

Site has no thermal or fault level issues.

Brimsdown 275kV

Site has no thermal or fault level issues.

Brinsworth 275kV

Not a GSP.

Brinsworth 400kV

Not a GSP.

Bramley 400kV

Site has no thermal or fault level issues.

Bridgewater 275kV

There are neither fault level nor thermal restrictions at the on the NG equipment at the GSP supplied by this substation. There are 6 spare bays at the HV substation that provides supplies to this GSP. Of the 2 SGTs at this GSP, only one of them has ter

Burwell 400kV

SGT capacity limit at the site.

Bushbury 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Bustleholm 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Canterbury 400kV

Regional voltage collapse limit. Active Network Management under development.

Capenhurst 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of two supergrid transformers with their tertiary generally not available to take on load.

Cardiff East 275kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green. No fault level issues. There are two SGTs, both have spare tertiary connections. There are no spare bays.

Carrington 400kV

Connections in this area are approaching a limit at the GSP. National Grid may invest in more capacity at this GSP, or look to create an operability scheme to flex generation under onerous conditions, depending on which solution is most economic and efficient. The site currently has no spare bays. The site consists of one supergrid transformer. It has available tertiary connection.

Cellarhead 400kV

The transmission capacity for demand connection at this site is approaching the limits. Therefore, connection of embedded generation with baterry technology is likely to require reinforcement.

Chickerell 400kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development.

Chessington 275kV

Site has no thermal or fault level issues.

Chesterfield 275kV

The Red status has been assigned for battery connections only and the site has a Green status for all other generation technology types. The site currently has no spare bays. The site consists of four supergrid transformers. The supergrid transformers have three available tertiary connections.

Cilfynydd 400kV

Not a GSP.

Cilfynydd 275kV

Not a GSP.

City Road 400kV

Site has no thermal or fault level issues.

Cleve Hill 400kV Substation

Not a GSP.

Connah's Quay 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP. National Grid will either require the DNO and the developers to arrange a flexible operating arrangement (e.g. ANM) to prevent GSP limits being breached. The site currently has no spare bays. The site consists of four supergrid transformers. Three supergrid transformers have available tertiary connections.

Coryton South 400kV

Not a GSP.

Cottam 400kV

Not a GSP.

Coventry 275kV

The Red status has been assigned for battery connections only and the site has a Green status for all other generation technology types. The site currently has no spare bays. The site consists of four supergrid transformers. The supergrid transformers have two available tertiary connections.

Cowley 400kV

Site has no thermal or fault level issues.

Creyke Beck 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Culham Jet 400kV

Not a GSP.

Daines 400kV

Not a GSP.

Deeside 400kV

Not a GSP.

Didcot 400kV

Not a GSP.

Dinorwig 400kV

Not a GSP.

Drakelow 400kV

Site has no thermal or fault level issues. The 400 kV site currently has two spare bays. The 132 kV site current has 2 spare bays. The site consists of two supergrid transformers. Both supergrid transformers have available tertiary connections.

Drax 400kV

The fault level is approaching the capability limits and hence connection of embedded generation of any type is likely to require reinforcement.

Dungeness 400kV

Not a GSP.

Ealing 275kV

Site has no thermal or fault level issues.

Eaton Socon 400kV

SGT capacity limit at the site.

East Claydon 400kV

The Red status has been assigned for battery connections only and the site has a Green status for all other generation technology types. The site currently has no spare bays. The site consists of four supergrid transformers. The supergrid transformers have two available tertiary connections.

Eggborough 400kV

Not a GSP.

Elland 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Elstree 400kV

Fault level limit at the site.

Enderby 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of four supergrid transformers. The supergrid transformers have two available tertiary connections.

Exeter Main 400kV

There are currently fault level restrictions on assets at this GSP. However, there are temporary measures to address this fault level issue whilst a permanent solution is delivered. Any connection prior to the permanent solution being delivered would be subject to constraining under certain conditions. There are no thermal restrictions. Of the three SGTs at this substation, only one has tertiary available for connection of generation.

Fawley 400kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development. And fault level limit at the site.

Feckenham 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Ferrybridge 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Ffestiniog 275kV

Not a GSP.

Fiddler's Ferry 275kV

The fault level is approaching the capability limits. The site currently has no spare bays. The site consists of four supergrid transformers. Two of them have available tertiary connections, other two supergrid transformers are generally not available to take on load at their tertiary side.

Fleet 400kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development.

Fourstones 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Frodsham 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of three supergrid transformers. One of them has no available tertiary connection, other two are generally not available to take on load at their tertiary side.

Grain 400kV

Not a GSP.

Grendon 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of five supergrid transformers. The supergrid transformers have three available tertiary connections.

Grimsby West 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Greystones B 275kV

Not a GSP.

Greystones 275kV

Not a GSP.

Hackney 400kV

Site has no thermal or fault level issues.

Hams Hall 400kV

Added because Lea Marston fed from here. Applied same colour and commercial status as Lea Marston.

Lea Marston 132kV Substation

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Harker 400kV

Connections in this area are, under onerous operating conditions, approaching a thermal limit at the GSP. Fault levels on the 275kV substation are high and would become a concern with additional connections.

Hartmoor 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Hartlepool 275kV

Not a GSP.

Hawthorn Pit 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Hedon 275 kV S/s

Not a GSP.

Heysham 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

High Marnham 400kV

Not a GSP.

Hinkley Point 400kV

Not a GSP.

Humber Refinery 400kV

Not a GSP.

Hurst 275kV

Site has no thermal or fault level issues.

Hutton 400kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Imperial Park 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of two supergrid transformers. None of them have available tertiary connections.

Indian Queens 400kV

Generation output would subject to constraining as instructed by the ANM scheme due to existing thermal restrictions at Alverdiscott. Given that Alverdiscott and Indian Queens GSPs are interconnected, ANM scheme also resticts embedded generation connected at Indian Queens.

Iron Acton 275kV

There no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green.

Ironbridge 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Iver 400kV

Site has no thermal or fault level issues.

Jordanthorpe 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Keadby 400kV

The fault level is approaching the capability limits and hence connection of embedded generation of any type is likely to require reinforcement. Also, the transmission capacity for demand connection is approaching the limits which is likely to require rei

Kearsley 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Kemsley (sheerness) 400kV

SGT capacity limit at the site.

Kirkby 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP. The site currently has no spare bays. The site consists of five supergrid transformers. Four of them have available tertiary connection, one supergrid transformer is generally not available to take on load at its tertiary side.

Killingholme 400kV

Not a GSP.

Kingsnorth 400kV

Fault level limit at the site.

Kirkstall 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Kitwell 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Knaresborough 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Lackenby 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Langage 400kV

Not a GSP.

Laleham 275kV

Site has no thermal or fault level issues.

Landulph 400kV

There are currently fault level restrictions on assets interconnected with this GSP. However, there are temporary measures to address this fault level issue whilst a permanent solution is delivered. Any connection prior to the permanent solution being delivered would be subject to constraining under certain conditions. There are no thermal restrictions. Of the 2 SGTs only one has a tertiary available for the connection of generation.

Legacy 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of four supergrid transformers. Four supergrid transformers have available tertiary connections.

Leighton Buzzard 400kV

Not a GSP.

Lister Drive 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP. The site currently has no spare bays. The site consists of four supergrid transformers. Four of them have available tertiary connections.

Littlebrook 400kV

Site has no thermal or fault level issues.

Littlebrook 275kV

Site has no thermal or fault level issues.

Lovedean 400kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development. And fault level limit at the site.

Macclesfield 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Margam 275kV

This applies to Grange 66kV substation - There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green. No fault level issues. There are two SGTs. There are no spare bays.

Mannington 400kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development.

Marchwood 400kV Substation

Not a GSP.

Melksham 400kV

The transmission assets (Bramley - Melksham) in proximity to this site are above their thermal limits and thus any additional generation at this site would require transmission reinforcement works. There are no fault level issues at this site. There are no spare bays and of the four SGTs on site, only two have tertiaries that are avalbale for the connection of generation.

Middleton 400kV

Not a GSP.

Mill Hill 275kV

Site has no thermal or fault level issues.

Minety 400kV

Site has no thermal or fault level issues.

Monk Fryston 400kV

Not a GSP.

Nechells 275kV

The fault level is approaching the capability limits and hence connection of embedded generation of any type is likely to require reinforcement. Also, the transmission capacity for demand connection is approaching the limits which is likely to require rei

Necton 400kV

Not a GSP.

Neepsend 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Newcross 275kV

Site has no thermal or fault level issues.

Northfleet East 400kV

Site has no thermal or fault level issues.

Ninfield 400kV

Regional voltage collapse limit. Active Network Management under development.

Norton Lees 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Norton 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Norwich Main 400kV

SGT capacity limit at the site. ANM in place.

Nursling 400kV

Capacity limit on fleet-lovedean circuit. Active Network Management under development.

Ocker Hill 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Offerton 275kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Oldbury 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Osbaldwick 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Padiham 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Patford Bridge 400kV

Not a GSP.

Pelham 400kV

SGT capacity limit at the site.

Pembroke 400kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green. No fault level issues. There are two SGTs. There are no spare bays.

Penn 400kV

GSP has already reached its fault level limits.

Pentir 400kV

Thermal restrictions would have to be managed for battery connections when charging. The site has no thermal or fault level issues for generation connections. The site currently has no spare bays. The site consists of two supergrid transformers. Both supergrid transformers have available tertiary connections.

Penwortham 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Pitsmoor 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Poppleton 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Pyle 275kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Yellow. No fault level issues. There are two SGTs. There are no spare bays.

Rainhill 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP. The site currently has no spare bays. The site consists of four supergrid transformers. Four supergrid transformers are generally not loaded at their tertiary side.

Rassau 400kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Yellow. No fault level issues. There are two SGTs. There are no spare bays.

Ratcliffe-on-soar 400kV

Site has no thermal or fault level issues. The 400 kV site currently has one spare bay. The 132 kV site current has 2 spare bays. The site consists of four supergrid transformers. The supergrid transformers have two available tertiary connections.

Rayleigh 400kV

Site has no thermal or fault level issues.

Redbridge 275kV

Site has no thermal or fault level issues.

Rochdale 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Rocksavage 400kV

Not a GSP.

Castner Kellner 132kV

Connection of additional generation at this site would require transmission investment to overcome thermal restrictions.

Rowdown 400kV

Not a GSP.

Rugeley 400kV

GSP is approaching its thermal limit on demand increase. Connection of additional batteries (as load) may bring the GSP to its thermal limit.

Rye House 400kV

Site has no thermal or fault level issues.

Saltend North 275kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Saltend South 275kV

Not a GSP.

Saltholme 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Seabank 400kV

The transmission assets in proximity to this site are above their thermal limits and thus any additional generation at this site would require transmission reinforcement works. No spare bays and space around the site has been earmarked for other projects.

Sellindge 400kV

Regional voltage collapse limit. Active Network Management under development.

South Humber Bank 400kV

Not a GSP.

Sheffield City 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Shrewsbury 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Singlewell 400kV

Not a GSP.

Sizewell 400kV

Not a GSP.

St John's Wood 400kV

Site has no thermal or fault level issues.

Skelton Grange 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

South Manchester 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Spennymoor 400kV Substation

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Spalding North 400kV

Not a GSP.

South Shields 275kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

Stanah 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Stalybridge 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Staythorpe 400kV

The site has a existing SGT reverse power flow control scheme to manage current levels of embedded generation. The site currently has no spare bays. The site consists of two supergrid transformers. The supergrid transformers have one available tertiary connection.

Stella West 400kV

Added as a parent to Stella North and Stella South, and used the same colour and commercial status.

Stella North 132kV

GSP is approaching its thermal limit on demand increase. Connection of additional batteries (as load) may bring the GSP to its thermal limit.

Stella South 132kV

GSP is approaching its thermal limit on demand increase. Connection of additional batteries (as load) may bring the GSP to its thermal limit.

Stoke Bardolph 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of two supergrid transformers. Both supergrid transformers have available tertiary connections.

Stocksbridge 400kV

Not a GSP.

Sundon 400kV

Site has no thermal or fault level issues.

Sutton Bridge 400kV

Not a GSP.

Swansea North 400kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Yellow. No fault level issues. There are three 400/132 kV, two 400/275 kV and two 275/132 kV SGTs. All have spare tertiary connections.

Taunton 400kV

There are neither fault level nor thermal restrictions at the on the NG equipment at the GSP supplied by this substation. There are no spare bays at this substation. There is only one SGT at this GSP and its tertiary is available for the connection of generation. Space is available for addition of a second SGT for the connection of generation.

Templeborough 275kV

Not a GSP.

Thorpe Marsh 400kV

The fault level is approaching the capability limits and hence connection of embedded generation of any type is likely to require reinforcement. Also, high voltage management is required.

Thornton 400kV

Not a GSP.

Thurcroft 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Tilbury 400kV

Fault level limit at the site.

Tod Point 275kV

Not a GSP.

Tottenham 275kV

Site has no thermal or fault level issues.

Trawsfynydd 400kV

Site has no thermal or fault level issues. The site currently has no spare bays. The site consists of two supergrid transformers with their tertiary generally not available to take on load.

Tremorfa 275kV

Not a GSP.

Tynemouth 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Upper Boat 275kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green. No fault level issues. There are two SGTs. There are no spare bays.

Upper Boat 132kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green. No fault level issues.

Upper Boat 33kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green. No fault level issues. There are two SGTs. There are no spare bays.

Uskmouth 275kV

There is no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green. No fault level issues. There are three SGTs. There are no spare bays.

Walham 400kV

There no transmission capacity for the connection of thermal and battery generation at this site. For other types of generation, the site is categorised as Green.

Walpole 400kV

Site has no thermal or fault level issues.

Waltham Cross 400kV

Not a GSP.

Warley 275kV

Site has no thermal or fault level issues.

Washway Farm 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Watford South 275kV

Fault level limit at the site.

West Boldon 275kV

Connections in this area are, under onerous operating conditions, approaching a limit at the GSP.

West Burton 400kV

The Red status has been assigned for battery connections only and the site has a Green status for all other generation technology types. The 132kV site currently has two spare bays. The site consists of two supergrid transformers. Both supergrid transformers have available tertiary connections.

West Ham 400kV

Site has no thermal or fault level issues.

Whitegate 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Whitson 400kV

Not a GSP.

Whitson 275kV

Not a GSP.

Wincobank 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Willenhall 275kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP.

Willington East 400kV

Site is close to fault level ratings on the circuit breakers at the 132 kV substation. The site currently has no spare bays. The site consists of five supergrid transformers. All supergrid transformers have available tertiary connections.

Wimbledon 275kV

Site has no thermal or fault level issues.

Willesden 275kV

Site has no thermal. Site may have fault level issues due to hard to split running based on Willesden-Wimbledon circuit cut. SO NAP raise this issue and LZ/JC are working on it in SD.

West Melton 275kV

The fault level is approaching the capability limits and hence connection of embedded generation of any type is likely to require reinforcement. Also, some level of high voltage management is required.

West Thurrock 400kV

Site has no thermal or fault level issues.

West Weybridge 400kV

Site has no thermal or fault level issues.

Wylfa 400kV

There are no current or immediately anticipated restrictions for connections caused by the operation of assets at this GSP. The site currently has two spare bays. The site consists of two supergrid transformers. Both of them have available tertiary connections.

Wymondley 400kV

SGT capacity limit at the site. ANM in place.