Industry: Offshore Wind Energy | Asset: 5 MVA Platform Transformer | Location: Northern Europe, 12 km Offshore | Product: DGA-200 + LoRa | Result: 60% Cost Reduction vs. Cable-Based Monitoring
Background
A wind farm operator in Northern Europe manages a fleet of 5 MVA step-up transformers distributed across multiple offshore platforms, located 12 km from the nearest shore. Each platform transformer is a critical link in the energy supply chain — a failure would require costly offshore crane mobilization and months of downtime waiting for weather windows.
Prior to 2021, the operator relied on annual manual oil sampling — requiring helicopter or crew vessel transport, with a per-visit cost exceeding €8,000 per platform. No online monitoring was in place due to the prohibitive cost of running communication cables to each platform.
The Challenge
Offshore wind platforms represent the most demanding environment for transformer monitoring: unmanned operation (zero on-site maintenance personnel), no wired communication infrastructure (fiber optic cable installation costs €50,000+ per platform), salt-spray corrosion environment, limited physical access (helicopter/crew vessel only, weather-dependent), and highly variable transformer loading (wind speed dependent, frequent 0-100% cycling).
The operator needed a zero-maintenance monitoring solution that could transmit data to the onshore control center without cable infrastructure.
PAS DGA Solution
In 2021, the operator deployed DGA-200 monitors with LoRa wireless on all offshore platform transformers. DGA-200 combines a Pd alloy thin-film H₂ sensor (1-2 ppm detection) with an optional IR-PAS multi-gas module for CO, CH₄, C₂H₂, and C₂H₄ monitoring. The integrated LoRa module provides 10+ km wireless range — more than sufficient for the 12 km offshore distance to the onshore receiving station.
Installation was completed during a routine maintenance visit. The DGA-200 units were valve-mounted on energized transformers in under 1 hour each. LoRa gateway antennas were installed on the platform helideck railings for maximum line-of-sight.
Results
| Metric | Before (Annual Lab Sampling) | After (DGA-200 + LoRa) |
|---|---|---|
| Measurement frequency | 1× per year | Every 60 minutes (8,760× per year) |
| Data latency | 2-4 weeks (lab turnaround) | Real-time (onshore dashboard) |
| Annual monitoring cost per platform | €8,000+ (crew vessel + lab) | €0 (after initial investment) |
| Communication infrastructure cost | €50,000+ per platform (fiber optic) | €0 (LoRa wireless, included) |
| Maintenance visits | 1 per year | 0 (3+ years zero maintenance) |
After 3+ years of continuous operation, the DGA-200 fleet has required zero maintenance visits. Hydrogen baselines and trends for all 22 platform transformers are monitored from the onshore control center via a single dashboard. The operators now receive real-time alerts for any H₂ deviation exceeding 5 ppm/day — enabling condition-based maintenance planning during scheduled weather windows rather than reactive emergency response.
Key Takeaways
- LoRa wireless eliminated the communication barrier. The 60% cost reduction vs. cable-based monitoring was the deciding factor in the operator’s business case.
- Zero maintenance is non-negotiable offshore. Every maintenance visit costs thousands and depends on weather. The DGA-200’s zero-consumable design made the deployment economically viable.
- Fleet-wide trending transforms asset management. Comparing H₂ trends across 22 identical transformers enables early identification of outliers — transformers with abnormal behavior are flagged for investigation before any alarm threshold is reached.
- Continuous data revealed load-dependent gas patterns. Wind speed-correlated H₂ variations were identified — normal behavior that would have been misdiagnosed as a fault from a single annual sample.