Substation Workshop. 7 th February 2018

Transcription

1 Substation Workshop 7 th February

2 Agenda Welcome and Introductions Antony White Substation Design Overview Andy Moore Question & Answer Session Break 1500kVA Transformers James Devriendt & Andy Moore Question & Answer Session Close / Feedback Antony White Lunch 2

3 Andy Moore Lead Design Engineer, LPN Substation Design Overview 3

4 UKPN Substation Design Ideal Scenario Drivers behind the current policy Substation Locations Key Elements Requirements for a basement location UKPN s preferred basement solution Applicable to all areas but predominately an LPN Area guidance 4

5 Ideal Scenario Since 2011; UKPN s stance regarding new build developments has been: The normal location for a substation, whether in a separate building or integral to a customer owned building, is at ground level. This is a similar stance to all other DNOs. 5

6 Ground Level Location ~ Key Drivers 24hr unrestricted access ~ OFGEM KPI : Customer Minutes Lost (CML). Manual Handling ~ Design-out MH of heavy plant wherever possible. Working at Height ~ Design-out WAH wherever possible (e.g. cable entry). CDM Designing out risk installation, maintenance and de-commissioning 6

7 Substation Location: GRP Enclosure EDS _01 Unit or Padmount Substation in GRP Enclosure 7

8 Substation Location: Freestanding Brick EDS _15 Freestanding Brick-Built Substation for a Transformer up to 1000kVA (Earth Ring) 8

9 Substation Location: Ground level Integral EDS _20 Integral Substation for a Single Transformer up to 1000kVA 9

10 UKPN Substation Design Key Elements: Plant Layout Ventilation Cable entry Personnel access Plant access 10

11 UKPN Substation Design Current requirements are detailed in the UKPN Engineering Design Standard: EDS ~ Secondary Substation Civil Design & associated suite of drawings. Available on the G81 section of the UKPN website. 11

12 Substation Location: Basement EDS _30 Basement Substation for a Single Transformer up to 1000kVA 12

13 When considering basement locations: Maximum one level below ground floor 24hr unrestricted UKPN staff access Without recourse to a third party (e.g. via Security Guard). Dedicated normal stairway (e.g. no companionway ladders). Dual-locking arrangements (if necessary). Direct UKPN Plant Access 24hr unrestricted. Manual Handling kept to a minimum Natural Ventilation Scheme Open to free air. Passive Stack principle employed. Maintenance free. 13

14 24hr Unrestricted Personnel Access UKPN dedicated stairway > < Access without 3 rd party involvement 14

15 Direct Plant Access Plant installation via running beam > Plant installation via running beam & hatch; minimising manual handling > & Plant access hatch > < Drop zone from above close to substation < Minimising manual handling 15

16 UKPN s preferred basement solution: The Lightwell substation < Personnel access without 3 rd party involvement Via dedicated stairway > 16

17 Lightwell substation cont d: < Direct plant access via HIAB crane Direct plant access with minimal manual handling > Open to free air ^ Passive stack principles Maintenance free 17

18 When things go wrong - Simple 18

19 When things go wrong - Complex 19

20 Substation Design Summary: Although we will always look for a ground level location in the first instance; UKPN will consider substations located in a basement. A number of aspects need to be considered if we are to meet our own requirements in terms of Health & Safety and network security. Each project requiring a substation will be assessed on its individual circumstances; providing the mandatory elements can be achieved. 20

21 Answering your questions 21

22 James Devriendt Connections Manager, SPN & Andy Moore Lead Design Engineer, LPN 1500kVA Transformers 22

23 Context UK Power Networks charged with stimulating and supporting a competitive market Market share has reduced significantly in majority of relevant market sectors Service delivery has demonstrably improved in recent years Appetite for more competitive offering is increasing Customers want UK Power Networks to be more flexible in offering 23 23

24 Transformers 11kV transformer specification has typically been limited to 1MVA Reduced unit diversity leads to lower unit cost and simpler maintenance schedule Automatic loss of Connections market share to IDNOs, particularly in high land-value / physically constrained locations We have reviewed specification options with a number of customers to determine most useful offering 1500kVA unit with 2500A LV circuit breakers sourced 24 24

25 Current Status Asset Management have reviewed options Standard Drawings drafted Engineering Bulletin issued for comment (internally) Relevant standards in the process of being updated on G81 25

26 Considerations Increased floor loading (compared to 1MVA) Increased ventilation requirements (compared 1MVA) ACB must be close coupled to the transformer (e.g. not wall mounted) 1m deep cable trenches required (due to close coupled ACB) and bending radius requirements for 630mm singles Customer installed back up generation would be strongly recommended 26

27 Uses Single connected customers (only) includes BNO, TBS and IDNO Outstanding constraints Basement locations currently not approved GRP locations currently not approved Refurbishments / upgrades out of scope 27

28 Current drawing 28

29 Answering your questions 29

30 Feedback & Thank you! 30