Customer:
Engineering Institute
Application:
Hydrogen Purity Monitoring and Alarm for Power Generator Cooling Systems
Product Used:
Moore Industries SPA2 Programmable Limit Alarm Trip
Overview
Hydrogen is widely used as a cooling medium in large power generators because of its superior thermal conductivity compared to air. At 100°C, hydrogen’s thermal conductivity (6.80) is nearly seven times higher than air (1.00), allowing it to efficiently remove heat from generator windings and maintain safe operating temperatures.
Maintaining high hydrogen purity levels is critical. Even minor contamination from air, oil vapor, or water can cause significant generator inefficiencies. For example:
- A 1% reduction in hydrogen purity creates a 12% increase in windage losses.
- A reduction in purity from 99% to 92% can reduce a 200 MW generator’s output by as much as 2,000 kW, driving up fuel costs and replacement power expenses.
Additionally, hydrogen mixed with air in the presence of an ignition source is explosive, making purity not only an efficiency issue but also a safety-critical factor.
The Challenge
Operators needed a reliable, high-integrity alarm system to continuously monitor hydrogen purity levels. The solution had to:
- Provide instantaneous alarm trip action in the event of purity falling below safe thresholds.
- Deliver fail-safe performance to ensure personnel and asset safety.
- Integrate seamlessly into the generator’s control and trip system to prevent catastrophic events and costly downtime.
The Moore Industries Solution
Application diagram of the SPA2 Programmable Limit Alarm Trip to alert Hydrogen contamination within a power generator cooling system
Key features of the SPA2 that addressed the challenge:
- Multiple programmable trip outputs for staged alarming (early warning vs. critical shutdown).
- User-friendly configuration to set precise alarm points for hydrogen purity.
- Proven reliability in critical trip applications within the power generation industry.
- Built-in fault monitoring to detect input sensor failure or wiring issues.
- By integrating the SPA2 into the generator’s trip system, plant operators gained a trusted safeguard against both efficiency losses and explosive hazards.
Why Moore Industries:
- Improved generator efficiency by ensuring hydrogen purity is maintained at safe, optimal levels.
- Avoided potential 2,000 kW output loss, reducing fuel costs and the need for costly replacement power.
- Enhanced plant safety, with fast-acting trip functions protecting against the dangerous hydrogen-air mixture scenario.
- Increased operational confidence, with reliable alarm trips that plant personnel trust to protect equipment and people.
Conclusion
Hydrogen cooling is essential to maintaining the efficiency of large power generators, but its safe use depends on maintaining high purity levels. The Moore Industries SPA2 Programmable Limit Alarm Trip provides power plant operators with a reliable, configurable, and fast-acting safeguard against purity-related efficiency losses and explosive hazards.
With the SPA2, utilities can protect both their assets and personnel while ensuring their generators operate at peak efficiency.