Asset Management, Operations, and Maintenance
This domain tests how a utility decides what to maintain, replace, or run to failure, and how those decisions are documented against risk, cost, and service metrics.
Frameworks
- ISO 55000 defines an asset management system built on value realization, alignment, and leadership; the asset management plan links asset strategies to the service obligation.
- Maintenance strategies: reactive (run to failure), preventive time-based, predictive condition-based, and reliability-centered maintenance, which targets failure modes by consequence.
- FMEA and criticality analysis rank assets by probability and consequence, including safety and environmental consequence, not only outage cost.
Condition assessment
- Transformers: dissolved gas analysis interpreted with the Duval triangle or IEEE key gases, oil quality testing, turns ratio, sweep frequency response, and partial discharge detection.
- Switchgear and breakers: timing and travel analysis, contact resistance, partial discharge, SF6 density and moisture.
- Lines and structures: thermography, corona and audible noise surveys, pole decay testing, vegetation clearance cycles, LiDAR inspection.
- Rotating plant: vibration analysis, lube oil analysis, performance testing against the heat-rate curve.
Worked example
A 40-year-old transformer has a 4% annual probability of failure, and a failure would cost 1.5 million dollars in replacement plus unserved energy. Expected annual failure cost = 0.04 x 1,500,000 = 60,000 dollars. A condition-based monitoring program costs 25,000 dollars per year and reduces failure probability to 1.5%, cutting expected cost to 22,500 dollars. Total annual cost falls from 60,000 to 47,500 dollars, justifying the program on economics alone; safety and environmental consequence strengthen the case.
Operations
- Work management, outage coordination with the reliability coordinator, switching procedures, clearance and tagging, and spare parts strategy.
- KPIs include availability, mean time between failures, SAIDI and SAIFI contribution by asset class, maintenance backlog, and capital renewal backlog.
Traps that cost marks
- Treating age alone as a replacement criterion rather than condition and consequence.
- Assuming preventive maintenance dominates predictive maintenance in every case.
- Excluding safety and environmental consequences from criticality scoring.
- Using a single dissolved gas reading instead of a trend.
- Confusing equipment reliability metrics with system reliability indices.