Project Type: Clustered Utility-Scale Grid-Side Battery Energy Storage Systems
Total Capacity: 1.5 GW (Phased Implementation)
Location: Nationwide Portugal, with focus on Alentejo, Central, and Northern regions
Project Owners: Portuguese National Grid Operator (REN) and multiple renewable energy developers
Technical Scope: Medium Voltage (MV) Switchgear, High Voltage (HV) Substation, and System Integration Solutions
Commercial Operation Dates (COD): Starting Q1 2027 with phased commissioning
| Project Scale | Number of Sites | Single Site Capacity | Voltage Level | Target COD | Primary Function |
|---|---|---|---|---|---|
| Large Hub Stations | 2 | 300 MW / 600 MWh | 220 kV | 2027 Q4 | Regional Frequency Regulation, Reserve Capacity |
| Medium Hub Stations | 4 | 150 MW / 300 MWh | 110 kV | 2027 Q3 | Renewable Smoothing, Voltage Support |
| Distributed Sites | 10 | 50-100 MW | 33-60 kV | 2027 Q2 | Local Grid Support, Peak Shaving |
| Small Access Points | 12 | 5-30 MW | 15-20 kV | 2027 Q1 | Distribution Grid Reinforcement, Community Storage |
Technical Solutions
A. Medium Voltage Switchgear Solutions (15-60 kV)
1. Standardized BESS-Dedicated Switchgear Series
Product Series: ESS-PACK-MV (Energy Storage System MV Integration Package)
Key Ratings:
Voltage: 15 kV, 24 kV, 36 kV, 40.5 kV, 60 kV
Current: 1250 A, 2000 A, 3150 A (customizable)
Short-Circuit Breaking: 25 kA, 31.5 kA, 40 kA
Core Technical Features:
Fast Operation Capability: Circuit breakers with full opening time < 50 ms to support rapid grid response.
High Cycling Endurance: Designed for > 50,000 mechanical operations and frequent switching cycles typical of BESS operation (3-5 cycles/day).
Arc-Resistant Design: Optional arc-flash resistant construction (up to IEEE C37.20.7 Class 2B) for enhanced safety in containerized environments.
Smart Protection Integration: Pre-configured for integration with BESS Energy Management System (EMS), including differential protection for transformer and battery converter interfaces.
Modular & Scalable: Pre-fabricated, containerized MV modules (e.g., "Power Conversion Container" with switchgear, transformers, PCS) for rapid on-site deployment.
B. High Voltage Substation Solutions (60-220 kV)
1. GIS Substation for Large Hub Stations (220 kV)
Configuration: Hybrid Air-Insulated Busbar (AIS) / Gas-Insulated Switchgear (GIS).
220 kV GIS for critical bays (incoming grid, transformer feeder).
Compact design with minimized footprint.
Key Components & Features:
Power Transformers: 300 MVA, 220/33 kV, ONAF/ONAN cooling, with on-load tap changers for voltage regulation.
Reactive Power Compensation: Static Synchronous Compensators (STATCOMs) or SVCs (± 100 MVAR) co-located for dynamic grid support.
Grid-Forming Inverter Interface: Dedicated bays and protection for grid-forming BESS inverters, ensuring black-start capability and system strength.
Cybersecurity: IEC 62443 compliant substation automation and hardended remote access.
2. Prefabricated Substation for Medium & Distributed Sites (33-110 kV)
Solution: All-in-one, transportable "e-House" or modular substation.
Design Philosophy: Factory-assembled, tested, and commissioned substations delivered in containerized modules.
Standard Layout Includes:
HV GIS Section (e.g., 110 kV, 5-bay ring main configuration).
Auxiliary Transformer & LVAC Board.
Control & Relay Room with SCADA and protection panels.
Fire Suppression & HVAC System.
Cable Connection Chambers.
System-Wide Integration & Control
1. Hierarchical Control Architecture
Level 1 (Site Level): Local EMS for optimal battery cycling, setpoint tracking.
Level 2 (Cluster Level): Aggregator control platform for managing multiple sites within a region for portfolio services.
Level 3 (System Level): REN's central dispatch interface for TSO-level services (frequency control, congestion management).
2. Specialized Protection Schemes
Battery Protection: DC arc-fault detection, battery management system (BMS) interlocks.
Converter Protection: Fast overcurrent, anti-islanding, harmonic overload protection.
Grid Interconnection Protection: Adaptative protection settings for different grid modes (charging/discharging, islanded).
Project Execution & Timeline
Phase 1 (2024-2025): FEED Studies, Grid Impact Assessments, and Procurement for early sites (5-30 MW).
Phase 2 (2025-2026): Detailed Engineering, Manufacturing, and Site Preparation for 50-150 MW sites.
Phase 3 (2026-2027): Manufacturing, Installation, and Commissioning of Large Hub Stations (300 MW).
Phase 4 (2027+): System-wide Integration, Performance Testing, and Full Commercial Operation.
Value Proposition for Portugal's Energy Transition
Grid Stability: Provides essential inertia and fast frequency response to complement high solar and wind penetration.
Renewable Integration: Enables higher hosting capacity for new solar PV in sun-rich regions like Alentejo.
Infrastructure Optimization: Defer or avoid costly grid upgrades through strategic placement of storage.
Market Participation: Enables project owners to generate revenue through energy arbitrage and ancillary service markets.
Energy Security: Enhances national and regional energy independence and resilience.
This portfolio of solutions demonstrates a scalable, standardized approach to delivering the critical grid infrastructure needed to integrate Portugal's ambitious 1.5 GW energy storage target, ensuring reliability, safety, and cost-effectiveness across projects of varying sizes.
