Appendix C – Future Power Flows

Electricity Ten Year Statement 2017 Electricity Ten Year Statement 2017 1 Appendix Contents

To demonstrate the impact of future changes on the transmission network a set of winter peak power flow C diagrams are presented in Appendix C. These show snapshots of present and future power flows along major circuit routes for the Two Degrees and Steady State Scenarios. The expected changes in the network are based on the previous year’s development decisions. Power flow diagrams

Appendix C

C1 – GB Power Flow Diagram Two Degrees 2017/18...... 2 C2 – GB Power Flow Diagram Two Degrees 2019/20...... 3 C3 – GB Power Flow Diagram Two Degrees 2021/22...... 4 C4 – GB Power Flow Diagram Two Degrees 2023/24...... 5 C5 – GB Power Flow Diagram Two Degrees 2026/27...... 6 C6 – GB Power Flow Diagram Steady State 2021/22...... 7 C7 – GB Power Flow Diagram Steady State 2023/24...... 8 C8 – GB Power Flow Diagram Steady State 2026/27...... 9 A ppendi x C x C ppendi A 2 Figure C1: GB Power Flow Diagram Two Degrees 2017/18

400kV Substations 275 kV Substations 132kV Substations Offshore AC Platform Offshore DC Platform 400kV Circuits 275kV Circuits 220kV Circuits 132kV Circuits Offshore AC Cable Offshore DC Cable Interconnectors (as of Nov 2017 IC Register) Dounreay Thurso Reconductor Circuit 264 Mybster New Circuit / Network changes Cassley Stornoway Dunbeath 1234 Power Flow MW

Lairg Flow Direction

Brora Harris Shin Loch Buidhe Major Generating Sites Including Pumped Storage

400 Connected at 400kV Mossford Grudie Bridge Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin Elgin Macduff St. Fergus Ardmore Deanie 90 Keith Culligran Dingwall Strichen Nairn Blackhillock Offshore Wind Projects (as of Oct 2017 - TEC) Aigas Kilmorack Inverness Dunvegan Peterhead Beauly 444 621 Knocknagael 194 Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 42 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 829

Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 403 Errochty 458 Rannoch Scottish Territorial Waters Sites 175 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Cruachan Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits 1020 346 St. Fillans Nant Clachan Inverarnan intact and no boundary constraints applied. SCOTTISH HYDRO-ELECTRIC 393 Cupar Inveraray Sloy TRANSMISSION Glenrothes 287 Leven 183 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill 552 Bathgate Crystal Rig Torness Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Crossaig 1088 Hunterston Neilston Clydes Mill 161Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 155 East Black Law Marshall Meadows Busby East 85 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels24 South Coalburn Galashiels Ayr 683 278 Clyde (North) Coylton Clyde (South) 1223 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes

Kendoon Ewe Hill 478 CarsfadBlackcraig To Northern Ireland Markhill 150 Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross820 Harker South Shields 60 247 Stella West Tongland West Boldon Glenluce Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 2260 546 Lackenby

353 Hutton 426 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 210 Fryston754 Saltend North Hedon Penwortham Drax Humber Gateway 766 Elland Saltend South Eggborough Rochdale Ferrybridge To Ireland 360 To Ireland Washway Keadby Humber Refinery Thorpe Farm Kearsley Whitegate Templeborough Killingholme Kirkby 866 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs Connah’s Quay High Dinorwig 2242 South Manchester Connah’s Quay Marnham Sheringham Shoal 2980 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 1542 Bicker Fen 610 Ratcliffe 2115 Willington on Soar Trawsfynydd 1548 2700 Drakelow Walpole Rugeley Spalding2150 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Scroby sands Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 2220 Coventry 2140 Oldbury 1816 Kitwell Berkswell 750

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 1190 Socon 2100 Patford Bramford Bridge 1770 230 Greater Gabbard 635 Sundon East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 594 Walham Waltham 1017 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 1405 Swansea North 408 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 1813 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 1452 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington Beddington East West Weybridge Rowdown Bramley 992 826 Fleet Canterbury 532 North 500 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 334 251 Bolney 645 Taunton Nursling 515 1565 Dungeness 707 Mannington Marchwood Lovedean Ninfield Axminster 1192 155 Fawley Botley Wood Exeter 135 To France

11 Chickerell To France

Langage Abham

Indian Queens Landulph 3 Figure C2: GB Power Flow Diagram Two Degrees 2019/20

400kV Substations 275 kV Substations 132kV Substations Offshore AC Platform Offshore DC Platform 400kV Circuits 275kV Circuits 220kV Circuits 132kV Circuits Offshore AC Cable Offshore DC Cable Interconnectors (as of Nov 2017 IC Register) Dounreay Thurso Reconductor Circuit Spittal 150 206 Mybster New Circuit / Network changes Cassley Beatrice Stornoway Dunbeath 1234 Power Flow MW

Lairg Flow Direction

Brora Harris Shin Loch Buidhe Major Generating Sites Including Pumped Storage

340 Connected at 400kV Mossford Grudie Bridge Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin Elgin Macduff St. Fergus Ardmore Deanie 33 Keith Culligran Dingwall Strichen Offshore Wind Projects (as of Oct 2017 - TEC) Nairn Blackhillock 456 Aigas Kilmorack Inverness Dunvegan Peterhead Beauly 374 955 Knocknagael 93 Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 60 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Aberdeen Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 1072 Kincardine Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 568 Errochty 662 Rannoch Scottish Territorial Waters Sites 148 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Cruachan Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits 1236 512 St. Fillans Nant Clachan Inverarnan intact and no boundary constraints applied. SCOTTISH HYDRO-ELECTRIC608 Cupar Inveraray Sloy TRANSMISSION Glenrothes 294 Leven 176 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill Bathgate Crystal Rig Torness Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Crossaig 1370 Hunterston Neilston Clydes Mill 13Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 172 East Black Law Marshall Meadows Busby East 270 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels35 South Coalburn Galashiels Ayr 773 Clyde (North) Coylton Clyde (South) 1692 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes

Kendoon Ewe Hill 527 CarsfadBlackcraig To Northern Ireland 186 Markhill Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross1347 Harker South Shields 59 282 Stella West Tongland West Boldon Glenluce Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 946 2260 Lackenby

690 Hutton 930 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 54 Fryston1475 Saltend North Hedon Penwortham Drax Humber Gateway 595 Elland Saltend South Eggborough Rochdale Ferrybridge To Ireland 2305 To Ireland Washway Keadby Humber Refinery Farm Kearsley Templeborough Thorpe Whitegate Killingholme Triton Knoll Kirkby 416 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs High Dinorwig Connah’s Quay 1955 South Manchester Connah’s Quay Marnham Sheringham Shoal East Anglia 2640 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 525 Bicker Fen 595 Ratcliffe 1745 Willington on Soar Trawsfynydd 562 2370 Drakelow Walpole Rugeley Spalding1140 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 1900 Coventry 1580 Oldbury 1165 Kitwell Berkswell 320

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 790 Socon 1800 Patford Bramford Bridge 973 690 Greater Gabbard 500MW 245 Sundon East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 575 Walham Waltham 465 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 860 Swansea North 340 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 1155 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 1115 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington East Beddington Bramley West Weybridge Rowdown 2450 To Belgium 626 Fleet Canterbury 230 North 975 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 268 505 Bolney 1015 Taunton Nursling 1185 1935 Dungeness Marchwood 525 Mannington Chilling Lovedean Ninfield Axminster 1580 113 Fawley Botley Wood Exeter 15 To France

13 Chickerell Rampion To France

Langage Abham

Indian Queens Landulph

To France 4 Figure C3: GB Power Flow Diagram Two Degrees 2021/22

400kV Substations 275 kV Substations 132kV Substations Offshore AC Platform Offshore DC Platform 400kV Circuits 275kV Circuits 220kV Circuits 132kV Circuits Offshore AC Cable Offshore DC Cable Interconnectors (as of Nov 2017 IC Register) Dounreay Thurso 300 Reconductor Circuit 219 Mybster New Circuit / Network changes Cassley Beatrice Stornoway Dunbeath 1234 Power Flow MW

Lairg Flow Direction Moray Firth Brora Harris Shin Loch Buidhe Major Generating Sites Including Pumped Storage

345 Connected at 400kV Mossford Grudie Bridge To Norway Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin Elgin Macduff St. Fergus Ardmore Deanie 42 Keith Culligran Dingwall Strichen Offshore Wind Projects (as of Oct 2017 - TEC) Nairn Blackhillock 468 Aigas Kilmorack Inverness Dunvegan Peterhead Beauly 320 949 Knocknagael 97 Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 58 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Aberdeen Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 1121 Kincardine Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 606 Errochty 699 Rannoch Scottish Territorial Waters Sites 164 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Inch Cape Cruachan Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits 1301 563 St. Fillans Nant Inverarnan intact and no boundary constraints applied. Clachan Neart na Gaolthe SCOTTISH HYDRO-ELECTRIC616 Cupar Inveraray Sloy TRANSMISSION Glenrothes 297 Leven 148 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill Bathgate Crystal Rig Torness To Norway Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Crossaig 1549 Hunterston Neilston Clydes Mill 277Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 178 East Black Law Marshall Meadows Busby East 421 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels48 South Coalburn Galashiels Ayr 1535 Clyde (North) Coylton Clyde (South) 2024 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes KendoonMargree 2036 Ewe Hill Dogger Bank 360 CarsfadBlackcraig To Northern Ireland 18 Markhill Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross2141 Harker South Shields 70 143 Stella West Tongland West Boldon Glenluce Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 2260 1850 Lackenby

1526 Hutton 1883 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton Hornsea West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 740 Fryston2420 Saltend North Hedon Penwortham Drax Humber Gateway 647 Elland Saltend South Eggborough Rochdale Ferrybridge To Ireland 1210 To Ireland Washway Keadby Humber Refinery Farm Kearsley Templeborough Thorpe Whitegate Killingholme Triton Knoll Kirkby 572 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs High Dinorwig Connah’s Quay South Manchester Connah’1435s Quay Marnham Sheringham Shoal East Anglia 2632 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 795 Bicker Fen 696 Ratcliffe 2145 Willington on Soar Trawsfynydd 846 2370 Drakelow Walpole Rugeley Spalding1330 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Scroby Sands Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 1916 Coventry 1660 Oldbury 1305 Kitwell Berkswell 153

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 600 Socon 1825 Patford Bramford Bridge 1062 1023 Greater Gabbard 500MW 210 Sundon East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 508 Walham Waltham 317 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 773 Swansea North 307 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 762 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 907 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington East Beddington Bramley West Weybridge Rowdown 2613 To Belgium 566 Fleet Canterbury 84 North1120 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 260 1102 Bolney 877 Taunton Nursling 1030 1800 Dungeness Marchwood Mannington Chilling Lovedean Ninfield 385 Axminster 1447 110 Fawley Botley Wood Exeter 180 To France To France 51 Chickerell Rampion

Langage Abham

Indian Queens Landulph

To France To France To France 5 Figure C4: GB Power Flow Diagram Two Degrees 2023/24

542 Connected at 400kV Mossford Grudie Bridge To Norway Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin Elgin Macduff St. Fergus Ardmore Deanie 10 Keith Culligran Dingwall Strichen Offshore Wind Projects (as of Oct 2017 - TEC) Nairn Blackhillock 578 New Deer Aigas Kilmorack Inverness Dunvegan Peterhead Beauly 172 1014 318 Knocknagael Rothiernorman Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 92 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Aberdeen Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 1621 Kincardine Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 960 Errochty 1154 Rannoch Scottish Territorial Waters Sites 130 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Inch Cape Cruachan Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits 1758 1147 St. Fillans Nant Inverarnan intact and no boundary constraints applied. Clachan58 Neart na Gaolthe SCOTTISH HYDRO-ELECTRIC North Argyll 1134 Cupar Inveraray Sloy TRANSMISSION Glenrothes Firth of Forth 328 Leven 149 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill Bathgate Crystal Rig Torness To Norway Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Branxton Crossaig 2272 Hunterston Neilston Clydes Mill 184Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 254 East Black Law Marshall Meadows Busby East 884 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels73 South Coalburn Galashiels Ayr 2408 Clyde (North) Coylton Clyde (South) 3216 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes KendoonMargree 3044 Ewe Hill Dogger Bank 586 CarsfadBlackcraig To Northern Ireland 140 Markhill Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross3285 Harker South Shields 255 Stella West Tongland West Boldon Glenluce Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 2260 2655 Lackenby

2070 Hutton 2400 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton Hornsea West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 1595 Fryston2685 Saltend North Hedon Penwortham Drax Humber Gateway 843 Elland Saltend South Eggborough Rochdale Ferrybridge To Ireland 1630 To Ireland Washway Keadby Humber Refinery Farm Kearsley Templeborough Thorpe Whitegate Killingholme Triton Knoll Kirkby 377 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers To Denmark North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs High Dinorwig Connah’s Quay South Manchester Connah’s1670 Quay Marnham Sheringham Shoal East Anglia 2663 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 45 Bicker Fen 730 Ratcliffe 2230 Willington on Soar Trawsfynydd 1353 2402 Drakelow Walpole Rugeley Spalding1692 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Scroby Sands Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 2115 Coventry 1435 Oldbury 1170 Kitwell Berkswell 214

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 570 Socon 2026 To Ireland Patford Bramford To Germany Bridge 850 Greater Gabbard 500MW 222 Sundon 1060 East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 430 Walham Waltham 140 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 795 Swansea North 358 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 157 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 612 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington Beddington East West Weybridge Rowdown Bramley 3346 To Belgium 290 Fleet Canterbury 200 North1996 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 163 2405 Bolney 625 Taunton Nursling 710 1550 To France Dungeness Marchwood Mannington Chilling Lovedean Ninfield 600 Axminster 1196 24 Fawley Botley Wood Exeter 142 To France To France 260 Chickerell Rampion

Langage Abham

Indian Queens Landulph

To France To France To France 6 Figure C5: GB Power Flow Diagram Two Degrees 2026/27

1092 Connected at 400kV Mossford Grudie Bridge To Norway Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin Elgin Macduff St. Fergus Ardmore Deanie 66 Keith Culligran Dingwall Strichen Offshore Wind Projects (as of Oct 2017 - TEC) Nairn Blackhillock 1062 New Deer Aigas Kilmorack Inverness Dunvegan Peterhead Beauly 570 1112 Knocknagael Rothiernorman 161 Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 110 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Aberdeen Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 2000 1722 Kincardine Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 774 Errochty 1096 Rannoch Scottish Territorial Waters Sites 84 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Inch Cape Cruachan Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits 1880 1161 St. Fillans Nant Inverarnan intact and no boundary constraints applied. Clachan94 Neart na Gaolthe SCOTTISH HYDRO-ELECTRIC North Argyll 1292 Cupar Inveraray Sloy TRANSMISSION Glenrothes Firth of Forth 332 Leven 145 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill Bathgate Crystal Rig Torness To Norway Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Branxton Crossaig 1148 Hunterston Neilston Clydes Mill 88Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 290 East Black Law Marshall Meadows Busby East 947 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles 2000 Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels76 South Coalburn Galashiels Ayr 2559 Clyde (North) Coylton Clyde (South) 2164 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes KendoonMargree 3178 Ewe Hill Dogger Bank 539 CarsfadBlackcraig To Northern Ireland 92 Markhill Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross3256 Harker South Shields 15 Stella West Tongland West Boldon Glenluce Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 2260 3030 Lackenby

2650 Hutton 3750 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton Hornsea West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 1590 Fryston2010 Saltend North Hedon Penwortham Drax Humber Gateway 455 Elland Saltend South Eggborough 1593 Rochdale Ferrybridge To Ireland To Ireland Washway Keadby Humber Refinery Farm Kearsley Templeborough Thorpe Whitegate Killingholme Triton Knoll Kirkby 752 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers To Denmark North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs High Dinorwig Connah’s Quay South Manchester Connah’1427s Quay Marnham Sheringham Shoal East Anglia 2600 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 158 Bicker Fen 700 Ratcliffe 2320 Willington on Soar Trawsfynydd 1665

2347 Drakelow Walpole Rugeley Spalding1835 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Scroby Sands Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 2315 Coventry 1600 Oldbury 1415 Kitwell Berkswell 308

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 795 Socon 2235 To Ireland Patford Bramford To Germany Bridge 1030 Greater Gabbard 500MW 405 Sundon 1047 East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 450 Walham Waltham 425 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 1258 Swansea North 493 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 320 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 640 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington Beddington East West Weybridge Rowdown Bramley 1703 To Belgium 636 Fleet Canterbury 470 North1062 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 280 1500 Bolney 342 Taunton Nursling 315 1270 To France Dungeness Marchwood Mannington Chilling Lovedean Ninfield 168 Axminster 872 140 Fawley Botley Wood Exeter 174 To France

273 Chickerell Rampion To France

Langage Abham

Indian Queens Landulph

To France To France To France 7 Figure C6: GB Power Flow Diagram Steady State 2021/22

400kV Substations 275 kV Substations 132kV Substations Offshore AC Platform Offshore DC Platform 400kV Circuits 275kV Circuits 220kV Circuits 132kV Circuits Offshore AC Cable Offshore DC Cable Interconnectors (as of Nov 2017 IC Register) Dounreay Thurso Reconductor Circuit Mybster New Circuit / Network changes Cassley Beatrice Stornoway Dunbeath 1234 Power Flow MW

Lairg 340 Flow Direction Moray Firth Brora Harris Shin Loch Buidhe Major Generating Sites Including Pumped Storage Connected at 400kV Mossford Grudie Bridge To Norway Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin Elgin Macduff St. Fergus Ardmore 480 Deanie 85 Keith Culligran Dingwall Strichen Offshore Wind Projects (as of Oct 2017 - TEC) Nairn Blackhillock *** Aigas Kilmorack Inverness Dunvegan Peterhead Beauly 570 930 Knocknagael 80 Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 60 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Aberdeen Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 1090 Kincardine Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 560 Errochty 630 Rannoch Scottish Territorial Waters Sites 60 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Inch Cape Cruachan Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits 1260 430 St. Fillans Nant Inverarnan intact and no boundary constraints applied. Clachan Neart na Gaolthe SCOTTISH HYDRO-ELECTRIC570 Cupar Inveraray Sloy TRANSMISSION Glenrothes 236 Leven 195 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill Bathgate Crystal Rig Torness To Norway Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Crossaig 1175 Hunterston Neilston Clydes Mill 240Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 180 East Black Law Marshall Meadows Busby East 150 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels30 South Coalburn Galashiels Ayr 660 Clyde (North) Coylton Clyde (South) 1400 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes KendoonMargree 1120 Ewe Hill Dogger Bank 178 CarsfadBlackcraig To Northern Ireland 163 Markhill Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross1160 Harker South Shields 43 200 Stella West Tongland West Boldon Glenluce Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 2260 980 Lackenby

440 Hutton 650 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton Hornsea West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 470 Fryston1370 Saltend North Hedon Penwortham Drax Humber Gateway 325 Elland Saltend South Eggborough Rochdale Ferrybridge To Ireland 295 To Ireland Washway Keadby Humber Refinery Farm Kearsley Templeborough Thorpe Whitegate Killingholme Triton Knoll Kirkby 480 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs High Dinorwig Connah’s Quay South Manchester Connah’1925s Quay Marnham Sheringham Shoal East Anglia 2245 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 88 Bicker Fen 810 Ratcliffe 1300 Willington on Soar Trawsfynydd 112 1980 Drakelow Walpole Rugeley Spalding1095 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Scroby Sands Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 2060 Coventry 1380 Oldbury 1045 Kitwell Berkswell 355

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 605 Socon 1950 Patford Bramford Bridge 1040 740 Greater Gabbard 500MW 275 Sundon East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 995 Walham Waltham 60 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 920 Swansea North 620 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 1040 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 1600 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington East Beddington Bramley West Weybridge Rowdown 1695 To Belgium 970 Fleet Canterbury 285 North1140 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 265 370 Bolney 630 Taunton Nursling 830 1550 Dungeness Marchwood Mannington Chilling Lovedean Ninfield 620 Axminster 1205 115 Fawley Botley Wood Exeter 155 To France To France 44 Chickerell Rampion

Langage Abham

Indian Queens Landulph

To France To France To France 8 Figure C7: GB Power Flow Diagram Steady State 2023/24

400kV Substations 275 kV Substations 132kV Substations Offshore AC Platform Offshore DC Platform 400kV Circuits 275kV Circuits To Shetland 220kV Circuits 132kV Circuits Offshore AC Cable 0 Offshore DC Cable Interconnectors (as of Nov 2017 IC Register) Dounreay Thurso Reconductor Circuit Spittal 200 Mybster New Circuit / Network changes Cassley Beatrice Stornoway Dunbeath 1234 Power Flow MW 0 Lairg Flow Direction 165 Moray Firth Brora Harris Shin Loch Buidhe Major Generating Sites Including Pumped Storage Connected at 400kV Mossford Grudie Bridge To Norway Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin 270 Elgin Macduff St. Fergus Ardmore Deanie 66 Keith Culligran Dingwall Strichen Nairn Blackhillock New Deer Offshore Wind Projects (as of Oct 2017 - TEC) Aigas Kilmorack Inverness Dunvegan 405 130 Peterhead Beauly 860 60 Knocknagael Rothiernorman Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 28 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Aberdeen Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 1070 Kincardine Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 570 Errochty 650 Rannoch Scottish Territorial Waters Sites 40 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Inch Cape Cruachan Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits 1260 517 St. Fillans Nant Inverarnan intact and no boundary constraints applied. Clachan58 Neart na Gaolthe SCOTTISH HYDRO-ELECTRIC North Argyll 660 Cupar Inveraray Sloy TRANSMISSION Glenrothes Firth of Forth 50 Leven 160 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill Bathgate Crystal Rig Torness To Norway Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Branxton Crossaig 1070 Hunterston Neilston Clydes Mill 350Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 180 East Black Law Marshall Meadows Busby East 100 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels32 South Coalburn Galashiels Ayr 310 Clyde (North) Coylton Clyde (South) 1240 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes KendoonMargree 775 Ewe Hill Dogger Bank 305 CarsfadBlackcraig To Northern Ireland 34 Markhill Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross790 Harker South Shields 200 Stella West Tongland West Boldon Glenluce Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 2260 625 Lackenby

445 Hutton 520 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton Hornsea West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 1595 Fryston910 Saltend North Hedon Penwortham Drax Humber Gateway 483 Elland Saltend South Eggborough Rochdale Ferrybridge To Ireland 420 To Ireland Washway Keadby Humber Refinery Farm Kearsley Templeborough Thorpe Whitegate Killingholme Triton Knoll Kirkby 505 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers To Denmark North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs High Dinorwig Connah’s Quay South Manchester Connah’1460s Quay Marnham Sheringham Shoal East Anglia 2490 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 310 Bicker Fen 585 Ratcliffe 1870 Willington on Soar Trawsfynydd 355 2220 Drakelow Walpole Rugeley Spalding1300 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Scroby Sands Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 1185 Coventry 1585 Oldbury 1180 Kitwell Berkswell 320

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 820 Socon 2060 To Ireland Patford Bramford To Germany Bridge 980 Greater Gabbard 500MW 535 Sundon 1045 East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 370 Walham Waltham 900 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 950 Swansea North 290 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 1295 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 612 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington Beddington East West Weybridge Rowdown Bramley 1905 To Belgium 200 Fleet Canterbury 200 North 660 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 115 415 Bolney 1100 Taunton Nursling 1300 2015 To France Dungeness Marchwood Mannington Chilling Lovedean Ninfield 240 Axminster 1680 70 Fawley Botley Wood Exeter 265 To France

7 Chickerell Rampion To France

Langage Abham

Indian Queens Landulph 170

To France To France To France 9 Figure C8: GB Power Flow Diagram Steady State 2026/27

400kV Substations 275 kV Substations 132kV Substations Offshore AC Platform Offshore DC Platform 400kV Circuits 275kV Circuits To Shetland 220kV Circuits 132kV Circuits Offshore AC Cable Offshore DC Cable Interconnectors (as of Nov 2017 IC Register) Dounreay Thurso 0 Reconductor Circuit Spittal 0 205 Mybster New Circuit / Network changes Cassley Beatrice Stornoway Dunbeath 1234 Power Flow MW 32 Lairg Flow Direction Moray Firth Brora Harris Shin Loch Buidhe Major Generating Sites Including Pumped Storage Connected at 400kV Mossford Grudie Bridge To Norway Connected at 275 kV Fyrish Alness Corriemoillie Fraserburgh Hydro Generation Luichart Orrin Elgin Macduff St. Fergus Ardmore 560 Deanie 88 Keith Culligran Dingwall Strichen Offshore Wind Projects (as of Oct 2017 - TEC) Nairn Blackhillock 700 New Deer Aigas Kilmorack Inverness Dunvegan 1060 Peterhead Beauly 835 730 Knocknagael Rothiernorman Fasnakyle Dyce Round 1 Kintore Persley Glen Broadford 46 Morrison Woodhill Willowdale Round 2 Caennacroc Foyers Clayhills Fort Augustus Boat of Quoich Garten Tarland Aberdeen Glendoe Craigiebuckler Redmoss Round 2.5 Invergarry 1000 1220 Kincardine Kinlochleven Round 3 Tummel Fiddes

Fort William Errochty Power Station 390 Errochty 565 Rannoch Scottish Territorial Waters Sites 70 Clunie Tummel Bridge Tealing Dudhope Arbroath Note : The power flows shown on this diagram represent the Lochay Cashlie Lyndhurst Milton of Craigie Economy planned transfer conditions as specified in appendix E Taynuilt Killin Charleston Dalmally Finlarig Dudhope Inch Cape Cruachan 1210 Burghmuir Glenagnes of the NETS SQSS. The network is complete with all circuits St. Fillans Nant Inverarnan intact and no boundary constraints applied. Clachan42 Neart na Gaolthe SCOTTISH HYDRO-ELECTRIC North Argyll 650 Cupar Inveraray Sloy TRANSMISSION Glenrothes Firth of Forth 357 550 Leven 177 Devonside Westfield Redhouse Whistlefield Kincardine Stirling Dunfemline Glenniston Helensburgh Denny Mossmorran Port Ann Longannet Inverkeithing Dunoon Bonnybridge Grangemouth Shrubhill Cockenzie Dunbar Spango Cumbernald BroxburnTelford Rd. Portobelllo Bainsford Gorgie Valley Strathleven Windyhill Bathgate Crystal Rig Torness To Norway Erskine Lambhill Whitehouse Devol Easterhouse Fallago Smeaton Moor Coatbridge Livingston Newarthill Currie Kaimes Branxton Crossaig 267 Hunterston Neilston Clydes Mill 260Black Law Extension NorthHunterston Strathaven Dunlaw Extension Berwick 200 East Black Law Marshall Meadows Busby East 132 Kilwinning Whitelee Wishaw Hunterston Kilmarnock Kilbride Saltcoats Town Whitelee ExtnSouth CoalburnLinnmill Eccles 1000 Meadowhead SP TRANSMISSION LTD Carradale Kilmarnock Galashiels82 South Coalburn Galashiels Ayr 500 Clyde (North) Coylton Clyde (South) 485 Elvanfoot Hawick New Cumnock Harestanes Maybole Moffat Auchenwynd New CumnockBlack Hill Glenglass Moffat Hadyard Dun Hill Harestanes KendoonMargree 964 Ewe Hill Dogger Bank 290 CarsfadBlackcraig To Northern Ireland 50 Markhill Glenlee Gretna Blyth Arecleoch Kilgallioch Earlstoun Dumfries Ecclefechan Auchencrosh Fourstones Newton Stewart Tynemouth Chapelcross978 Harker South Shields 60 Stella West Tongland West Boldon Glenluce 805 Offerton Hawthorne Pit Hartmoor Spennymoor Hartlepool Saltholme Tod Point Teesside Cashlie Norton Robin Rigg Greystones Grangetown 2260 435 Lackenby

1115 Hutton 1280 Ormonde

Walney I & II Quernmore Heysham Osbaldwick Knaresborough West of Duddon Sands Middleton Barrow Bradford Thornton Hornsea West Kirkstall Skelton Poppleton Creyke Beck Westermost Rough Stanah Padiham Grange Monk 475 Fryston1750 Saltend North Hedon Penwortham Drax Humber Gateway 345 Elland Saltend South Eggborough 925 Rochdale Ferrybridge To Ireland To Ireland Washway Keadby Humber Refinery Farm Kearsley Templeborough Thorpe Whitegate Killingholme Triton Knoll Kirkby 663 West Marsh South Burbo Bank Stalybridge Melton Humber Grimsby West Gwynt y Mor Carrington Pitsmoor West Wylfa Rainhill Stocksbridge Aldwarke Bank Birkenhead Winco Bank Burton Bredbury Neepsend Thurcroft Rhyl Flats Fiddlers To Denmark North Hoyle RocksavageRocksavage Daines Sheffield City Ferry Cottam Brinsworth Race Bank Dudgeon Flintshire Frodsham Jordanthorpe Bodelwyddan Bridge Macclesfield Norton Lees Pentir Inner Dowsing Capenhurst Chesterfield Lincs High Dinorwig Connah’s Quay South Manchester Connah’1285s Quay Marnham Sheringham Shoal East Anglia 2470 Staythorpe Lynn Legacy Ffestiniog Cellarhead Stoke Bardolph 50 Bicker Fen 590 Ratcliffe 2000 Willington on Soar Trawsfynydd 310 2205 Drakelow Walpole Rugeley Spalding1190 North Necton Ironbridge Sutton Norwich Main Bushbury Ryhall Bridge Scroby Sands Willenhall Bustleholm Shrewsbury Penn Enderby Nechells Hams Hall Ocker Hill 2556 Coventry 1720 Oldbury 1300 Kitwell Berkswell 620

Burwell Main Sizewell Feckenham Grendon Bishops Wood Eaton 890 Socon 2440 To Ireland Patford Bramford To Germany Bridge 1130 Greater Gabbard 500MW 600 Sundon 1360 East Claydon Pelham Braintree Wymondley Leighton Buzzard Greater Gabbard 2nd part (Galloper) Rassau 420 Walham Waltham 1190 Rye House Cross Rhigos Imperial Brimsdown Park Gunfleet Sands I&II Cowley 1265 Swansea North 355 Watford Elstree Highbury To Netherlands Pembroke Amersham Main Hackney London Array Cilfynydd Culham Tottenham Redbridge Rayleigh Main Baglan Bay Mill Hill Warley Upper Boat Uskmouth Minety Didcot Willesden Margam Iron Acton Coryton Iver Kensal Green West Ham Alpha Steel Whitson Barking Pyle Ealing Pudding St Johns City Rd Mill Grain Hurst West Thurrock Tilbury Seabank Wood Kentish Flats Wimbledon New Cross 880 Northfleet Thanet Tremorfa Laleham Littlebrook Kingsnorth 715 East Singlewell Kemsley Cleve Hill Aberthaw Cardiff Melksham Chessington East Beddington Bramley West Weybridge Rowdown 860 To Belgium 520 Fleet Canterbury 170 North 430 Hinkley Point Sellindge West Sellindge Bridgwater Alverdiscott 240 570 Bolney 535 Taunton Nursling 755 1460 To France Dungeness Marchwood 444 Mannington Chilling Lovedean Ninfield Axminster 1090 100 Fawley Botley Wood Exeter 40 To France

4 Chickerell Rampion To France

Langage Abham 170 Indian Queens Landulph

To France To France To France