The U.S. electric utility industry continues to undergo dramatic change due to a number of key trends and also prolonged uncertainty. These trends include:
• Increasing environmental regulations uncertainty
• Natural gas supply uncertainty and price
• Economic / decoupling of electricity demand growth from GDP
• Aging coal and nuclear generation fleet / coal retirements
• Aging workforce
• Increasing distributed energy resources
• Increasing customer expectations
The transformation ultimately demands significant increases in power plant generation operating capabilities (e.g. flexibility, operating envelop, ramp rates, turn-down etc.) and higher levels of equipment reliability, while reducing O&M and capital budgets. Achieving higher levels of equipment reliability and flexibility, with such tightening budget and resource constraints, requires a very disciplined approach to maintenance and an optimized mix of the following maintenance practices:
• Reactive (run-to-failure)
• Preventive (time-based)
• Predictive (condition-based)
• Proactive (combination of 1, 2 and 3 + root cause failure analysis)
Many U.S. electric utilities with fossil generation have adopted and implemented elements of an equipment reliability process consistent with Institute of Nuclear Power Operations (INPO) AP-913. The Electric Power Research Institute has created a guideline modeled from the learnings of AP-913, that consists of six key sub-processes :
1. Scoping and identification of critical components (identifying system and component criticality)
2. Continuing equipment reliability improvement (establishing and continuously improving system and component maintenance bases)
3. Preventive Maintenance (PM) implementation (implementing the PM program effectively)
4. Performance monitoring (monitoring system and component performance)
5. Corrective action
6. Life cycle management (long-term asset management)
A significant proportion of Duke Energy’s coal fleet is of an age where individual components have reached their design intent end-of-life thereby creating an increased need for performance monitoring. Until recent times this was largely performed by maintenance technicians with handheld devices. This approach does not allow regular data collection for trending and optimization of maintenance practices across the fleet.
Significant and recent advances in sensor technology, microprocessors, data acquisition, data storage, communication technology, and software have enabled the transformation of critical power plant assets such as steam turbines, combustion turbines, generators, transformers, and large balance-of-plant equipment into smart, connected power plant assets. These enhanced assets, in conjunction with visualization software, provide a comprehensive conditioning monitoring solution that continuously acquires sensory data and performs real time analysis to provide information and insight. This advanced condition monitoring capability has been successfully applied to obtain earlier detection of equipment issues and failures and is key to improving overall equipment reliability.
This paper describes an approach by Duke Energy to create and apply smart, connected power plant assets to greatly enhance its fossil generation continuous condition monitoring capabilities. It will discuss the value that is currently being realized and also look at future possibilities to apply big data and analytics to enhance information, insight, and actionable intelligence.