Direct Answer
Package substations in Saudi Arabia are supplied in four main configurations: compact kiosk substations for standard SEC-connected sites, skid-mounted substations for industrial process areas, containerised substations for remote and temporary deployments, and unitised substations for buildings and facilities served by external MV switchgear. Selection depends on site access, environmental exposure, load profile, and the need for future mobility or expansion.
Climate Considerations for Saudi Arabia
Before examining substation types, it is essential to understand the operating environment that all package substations in Saudi Arabia must be designed for. Any substation regardless of type installed in the Kingdom must address three primary environmental stressors:
Extreme Heat
Ambient temperatures of 45–55°C in summer (exceeding 60°C on exposed metal surfaces). Transformer cooling and enclosure ventilation must be sized for these conditions, not the IEC standard 40°C ambient.
Windborne Sand & Dust
Particularly in the Eastern Province, Western Region, and remote sites. Enclosures must be IP54 minimum, with sand-filtered forced ventilation to prevent filter clogging and motor burnout from abrasive ingress.
Coastal Corrosion
Salt-laden air within 5 km of coastlines Jubail, Yanbu, Jeddah, Ras Al Khair accelerates corrosion of enclosure steel, busbar connections, and cable terminations. Marine-grade materials and coatings are required.
IEC 62271-202 defines environmental classes for package substations. Saudi Arabia's outdoor industrial environments typically require Class E2 (severe pollution, condensation, heavy rain) as a minimum which mandates IP54 or higher, specific temperature endurance, and stringent corrosion protection.
The Four Main Package Substation Types
Type 01
Compact Kiosk Substation
The compact kiosk substation is the standard package substation type used for SEC-connected commercial and light industrial applications throughout Saudi Arabia. It integrates an SF₆ Ring Main Unit (RMU), oil-immersed or dry-type transformer, and LV distribution panel within a single purpose-built steel or GRP enclosure. The enclosure is designed as a complete unit not adapted from a container and is optimised for minimum footprint on a concrete pad. Typical ratings are 250 kVA to 1,600 kVA. SEC-approved compact substations are widely used in residential compounds, commercial buildings, university campuses, and light manufacturing facilities throughout Riyadh, Jeddah, Dammam, and Makkah. EAMFCO supplied compact package substations for the Jubail Naval Base (2,500 kVA) as well as water treatment and infrastructure projects across the Eastern Province.
Advantages
- Smallest footprint designed specifically for substation function
- Factory-assembled and type-tested to IEC 62271-202
- SEC-approved configurations readily available
- Lower cost than skid or containerised options for standard loads
- Available with IP33 to IP54 depending on outdoor/indoor application
Limitations
- Not intended to be relocated after permanent installation
- Limited internal space cannot accommodate auxiliary equipment beyond core components
- Standard units designed for 40°C ambient Saudi outdoor deployment requires upgraded thermal design
- Requires concrete pad preparation before delivery
Type 02
Skid-Mounted Substation
A skid-mounted substation mounts all components MV switchgear, transformer, LV panel, cabling, protection equipment, and auxiliary panels on a single structural steel skid frame. The skid serves as the base for all equipment rather than an enclosure. Individual components may be individually enclosed or weather-protected, but the skid itself is open. This type is the standard solution for industrial process areas in petrochemical plants, oil & gas facilities, water treatment plants, and fabrication yards where the substation is located inside an existing building or under a weatherproof canopy. Skid substations are also used where the transformer rating exceeds what a compact kiosk can accommodate typically above 2,500 kVA.
Advantages
- Handles large transformer ratings 2,500 kVA to 10,000+ kVA
- Can accommodate auxiliary panels, APFC, UPS, and metering cubicles on the same skid
- Modular individual components can be replaced or upgraded independently
- Standard for Saudi Aramco and NWC project specifications
- Lower cost at large ratings versus purpose-built enclosed substations
Limitations
- Requires a building, canopy, or shelter not self-protecting against the outdoor environment
- Larger footprint than compact kiosk type
- Longer installation time individual components must be connected and tested on site
- Heavier crane access required for installation and relocation
Type 03
Containerised Substation
A containerised substation mounts all substation components RMU, transformer, LV panel, and auxiliaries inside a standard ISO 20- or 40-foot shipping container, or a custom-built weatherproof steel container. The container provides a completely sealed, self-contained, and relocatable electrical installation. Containerised substations are the preferred choice for construction sites and temporary camps serving NEOM, Red Sea Project, and other Vision 2030 giga-projects where power infrastructure must be deployed rapidly, operated for several years, and then relocated as the project progresses. They are also used for permanent remote site installations pipeline pump stations, telecom towers, remote water booster stations where conventional civil substation construction is impractical.
Advantages
- Fully relocatable can be lifted by crane and transported by flatbed truck
- Fastest deployment delivered fully assembled and ready to energise
- Can include air conditioning, lighting, fire suppression, and SCADA in the same container
- Completely weatherproof suitable for outdoor desert and coastal environments without additional shelter
- Standard container dimensions simplify transport logistics
Limitations
- Higher capital cost than compact kiosk for equivalent rating
- Container floor space limits transformer size typically to 2,000 kVA in a 20-foot container
- Container ventilation must be carefully designed for Saudi heat inadequate ventilation leads to transformer overtemperature
- Requires level concrete pad or compacted gravel base for stability
Type 04
Unitised Substation
A unitised substation combines only a transformer and an LV distribution panel without an integrated RMU in a compact assembly. It connects to externally provided MV switchgear, which may be a standalone switchboard in the facility's main MV room or a separate RMU unit. Unitised substations are the standard solution for multi-storey commercial buildings, hospitals, data centres, and large retail developments in Saudi Arabia, where MV switchgear is centralised in a dedicated MV room and multiple unitised substations distribute power to individual floors or zones. They are typically installed indoors in dedicated electrical rooms.
Advantages
- Smallest footprint of all types no RMU component
- Lower cost than package substation external MV switchgear shared across multiple units
- Easier to install in tight building electrical rooms
- Dry-type or cast resin transformers eliminate oil containment requirements
- Can be installed in stacked configurations on multiple floors
Limitations
- Requires a separately engineered and installed MV switchgear system
- Not self-contained MV fault on the external switchgear affects all connected unitised substations
- Not suitable for outdoor or remote deployment
- MV cable routing from switchgear to each unit requires careful building coordination
Side-by-Side Comparison
| Parameter | Compact Kiosk | Skid-Mounted | Containerised | Unitised |
|---|---|---|---|---|
| MV switchgear | Integrated RMU | Integrated MV switchboard | Integrated RMU or switchboard | External (not included) |
| Typical rating | 250–1,600 kVA | 1,000–10,000+ kVA | 250–2,000 kVA | 250–3,150 kVA |
| Outdoor suitability | Yes (IP33–IP54) | No (needs shelter) | Yes (IP54–IP65) | No (indoor only) |
| Relocatable | Difficult | Yes (with crane) | Yes (crane/truck) | No |
| Deployment speed | Fast (pad + cable) | Moderate (site assembly) | Fastest (plug & play) | Moderate |
| Climate adaptation | Standard; upgrade needed for Saudi outdoor | N/A sheltered | Engineered per site | N/A indoors |
| Capital cost (relative) | Low–Medium | Medium–High | Medium–High | Low |
| Best for | SEC urban/suburban sites | Industrial process plants | Remote/temporary/mobile | Commercial buildings |
Typical Voltage Ratings for Saudi Projects
Voltage selection is determined by the SEC supply network or the project's internal MV distribution system. The following ratings apply across Saudi projects:
| MV Primary Voltage | Application | Typical Transformer kVA |
|---|---|---|
| 13.8 kV | Most common SEC supply voltage for urban industrial and commercial consumers in the Eastern Province, Riyadh, and Jeddah regions | 250–2,500 kVA |
| 33 kV | High-density industrial zones (Jubail Industrial City, Yanbu Industrial City, Ras Al Khair), large commercial developments, SEC bulk supply points | 1,000–5,000 kVA |
| 11 kV | Legacy SEC networks in some regions and private industrial networks less common in new projects | 250–2,500 kVA |
| 6.6 kV | Private industrial medium voltage distribution within large plants used for large motor loads (> 200 kW) where LV is impractical | Varies |
| LV Output (all types) | 380/400 V three-phase at 50 Hz the standard Saudi utilisation voltage per SEC and IEC 60038 | N/A |
All substation transformer windings must be specified for the exact SEC incoming voltage at the delivery point. Saudi SEC voltages can vary by up to ±10% of nominal under load. Off-load tap-changers (OLTC) with ±2×2.5% taps are standard on package substation transformers to allow voltage adjustment after commissioning.
Frequently Asked Questions
Q: What type of package substation is most common in Saudi Arabia?
A: The compact kiosk-type package substation is most widely used for SEC-connected commercial and light industrial applications. For oil & gas, remote infrastructure, and giga-projects, containerised and skid-mounted substations are preferred due to their mobility, rapid deployment capability, and ability to be specified for extreme outdoor environments including sand, heat, and salt-laden air.
Q: What is the standard incoming MV voltage for package substations in Saudi Arabia?
A: The two primary MV supply voltages are 13.8 kV (most common for urban and industrial areas) and 33 kV (used in high-density industrial zones including Jubail and Yanbu). Legacy systems may use 11 kV. The standard LV output in all cases is 380/400 V three-phase at 50 Hz.
Q: Can a package substation be used in an outdoor desert environment in Saudi Arabia?
A: Yes, but it must be specified for the actual site conditions. Saudi outdoor desert environments require as a minimum: IP54 or IP65 enclosure rating, forced ventilation with sand and dust filters, hot-dip galvanised or epoxy powder-coated steel, and transformer cooling systems rated for 50°C+ ambient. IEC 62271-202 Class E2 environmental classification applies.
Q: What is the difference between a compact substation and a containerised substation?
A: A compact substation is a purpose-designed all-in-one kiosk enclosure smaller, lighter, and lower cost for permanent fixed installation. A containerised substation uses a shipping container as the enclosure. Containerised units are larger, fully relocatable, and can house additional equipment including battery systems, SCADA panels, and APFC units. They are the standard choice for temporary sites, remote locations, and projects where relocation is anticipated.
EAMFCO - All Four Package Substation Types, Factory-Assembled for Saudi Projects
EAMFCO manufactures package and unit substations in compact kiosk, skid-mounted, and containerised configurations each integrating SF₆ RMUs, oil or dry-type transformers, and IEC 61439-compliant LV panels. All units are factory assembled and tested before delivery to Saudi project sites. Continue reading: