BESS Transformers
Purpose-built for battery energy storage systems — bidirectional power flow, cyclic overload capability, and harmonic tolerance for grid-scale BESS applications.
Engineering Features
Bidirectional Power Flow
Designed for charge/discharge cycling with optimized winding configuration for reverse power flow.
Technical Data
| Parameter | Range / Value |
|---|---|
| Rated Power | 1 – 300 MVA |
| Primary Voltage | 11 – 132 kV |
| Secondary Voltage | 400 V – 36 kV |
| Frequency | 50 / 60 Hz |
| Power Flow | Bidirectional |
| Cycle Rating | 5,000+ cycles/year |
| K-Factor | K13 – K20 |
| Ambient Temp | -20°C to +55°C |
| Insulation Fluid | Mineral / FR3 / Midel |
| Design Life | 30+ years |
Standard range parameters — custom specifications available on request.
Related glossary terms
ENATS 35-1
DNO-approved distribution transformer specification
ENATS 35-2
UK secondary substation transformer standard
G99 Compliant
Engineering Recommendation G99 grid interface
BS EN 60076
British Standard for power transformers
KEMA Certified
Independent short-circuit witness testing
EcoDesign Tier 2
EU 548/2014 efficiency compliance
Bidirectional, harmonic-tolerant step-up transformers purpose-built for UK Battery Energy Storage System (BESS) sites. 1 MVA to 100 MVA up to 132 kV — G99 grid-code compliant, designed for cyclic full-load operation in both directions and tolerant of harmonic content from grid-forming inverters. Supplied for stand-alone BESS, co-located solar + BESS and grid-services projects across the UK.
UK Standalone BESS · 100–500 MWh Sites
Co-located Solar + BESS · England & Wales
Grid-Services BESS · Frequency Response, FFR, DC
Capacity Market BESS · UK Auctions
Onshore Wind + BESS Hybrids · Scotland
Distribution-Connected BESS · UKPN, NIE, SP Energy
Where BESS Transformers Excel.
UK Grid-Scale BESS
G99-compliant BESS transformers for UK grid-scale battery storage projects across England, Scotland and Wales.
UK Capacity Market BESS
Bidirectional BESS transformers for UK Capacity Market, T-1 and T-4 auction projects providing peak capacity.
UK Co-located Solar + Storage
ENATS-compliant transformers for UK co-located solar and BESS projects on shared DNO connections.
UK Frequency Response BESS
BESS transformers for UK Dynamic Containment, Dynamic Moderation and Dynamic Regulation frequency-response projects.
Frequently Asked Questions
Related Knowledge
FAQs, glossary terms and sizing steps mapped to this product.
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