Who is SP Group / SP PowerGrid?
SP Group is the holding company. SP PowerGrid is the subsidiary that owns and operates Singapore's electricity transmission and distribution network — the cables under the streets, the substations on the corners, the metering at every connected building. Under licence from EMA, SP PowerGrid is the sole provider of grid connections in Singapore.
Whether you are a homeowner connecting a new condominium or an industrialist commissioning a 22 kV factory, your physical connection to the grid is via SP PowerGrid. They are not the retailer (that's any of the licensed electricity retailers under the Open Electricity Market), but they are the operator of the wires.
LT or HT? The first decision
The connection voltage depends on your maximum demand. Roughly:
- Low Tension (LT, 230/400 V) — small premises, typical residential, light commercial, demand up to a defined threshold (commonly cited around the 45 kVA level for single-phase / small three-phase).
- 22 kV High Tension intake — larger commercial and industrial demand. Requires the customer to build a 22 kV substation, switchgear, transformer and LV side.
- 66 kV intake — very large industrial demand or specific infrastructure (typically rail depots, large process plants).
SP confirms the connection voltage as part of the application — you can request a level, but they make the final call based on network capacity, demand, and policy.
The seven stages
- Preliminary enquiry. Owner or consultant submits a preliminary load estimate to SP PowerGrid. SP advises connection voltage, available capacity in the area, and indicative timeline.
- Formal application. A detailed application (the "Pink Folder" in older parlance, now a digital submission) is filed by the consultant or LEW, with single-line diagrams, load schedules, site plans and substation room details.
- Technical clarification. SP reviews the application and issues queries or Conditions of Service Connection. RFIs are responded to until SP is satisfied.
- Conditional approval. SP issues the technical conditions, capacity offer, contribution charge (if any) and approval to proceed.
- Construction. The owner builds the customer substation, installs HT cables, switchgear and transformer. SP simultaneously arranges its own works (incoming feeder cables, metering).
- Testing & Commissioning. Both sides (customer and SP) conduct T&C. The customer's LEW or PE conducts customer-side T&C; SP conducts its own.
- Energisation. SP performs the final HT switching to energise the cable into the customer substation. The customer LEW handles all subsequent switching downstream.
The technical conditions document
SP issues a Conditions of Service Connection document tied to each application. This typically prescribes:
- Substation room size, ventilation, fire compartmentation requirements.
- Switchgear specifications (e.g. SF6-insulated RMU at 22 kV).
- Transformer ratings, vector group (Dyn11), impedance.
- Protection co-ordination requirements at the customer-SP interface.
- Earthing and bonding requirements.
- Metering location and type.
- HT cable type, sizing, route requirements.
- Any specific contribution charges and timelines.
Realistic timeline
| Stage | Typical duration |
|---|---|
| Preliminary enquiry → application acceptance | 2–4 weeks |
| Application review → conditional approval | 1–3 months |
| Detailed design → equipment procurement (long-lead 22 kV switchgear, transformer) | 4–8 months |
| Installation | 2–4 months |
| T&C and SP energisation | 2–6 weeks |
Overall: 8 to 14 months for a typical 22 kV intake from preliminary enquiry to energisation. Longer if the SP feeder route requires road cutting permits, or if the local grid is at capacity.
Practical tips
- Talk to SP before detailed design. Capacity in your area can constrain feasible options. Build that constraint into your design assumptions.
- Lock in long-lead items early. 22 kV switchgear and transformer lead times can be six months or longer. Place orders against the conditional approval, not the final.
- Build the substation room first. SP's HT cable cannot terminate until the room is ready, accessible and meets the conditions. A delayed substation room delays the entire intake.
- Coordinate the LEW early. Your customer-side LEW needs to be briefed on the switching sequence well before energisation day.
- Engage a PE who has seen this before. SP RFIs are easier to close out when the consultant has been through several intakes.
Frequently asked questions
Can we get an LT supply instead of an HT one?
If your demand fits within LT limits, yes — and it is dramatically simpler. If your demand exceeds LT thresholds, SP will mandate HT.
Who owns the substation room and equipment?
On a customer 22 kV intake, the substation room and equipment are owned by the customer. SP owns the incoming HT cable and the metering. The demarcation is at the interface point defined in the Conditions.
What if the area has no spare capacity?
SP will say so up-front. Solutions may include phased connection, network upgrades funded partly by the customer, or relocation of the load. Always raise this at the preliminary enquiry stage.
How early can we order the transformer?
Most owners place the transformer order after conditional approval — once the rating and specification are locked in. Ordering before that carries the risk of having to re-specify.