The Connection Between Inventory Accuracy and Outage Success
Planned outages are the most expensive and time-critical events at a power plant. A nuclear refueling outage can cost $1–2 million per day in replacement power costs and labor. A fossil plant turnaround may run $500,000+ per day. Every day of extension directly hits the bottom line.
Research from the Electric Power Research Institute (EPRI) consistently shows that material availability is among the top causes of outage extensions. When a maintenance team opens a valve and needs a seal kit that the system says is in stock but isn't — that's not a maintenance failure, it's an inventory failure.
Accurate MRO inventory management is the foundation of outage success. Without it, every other outage planning effort is built on unreliable data.
Pre-Outage Inventory Planning Timeline
A structured timeline ensures materials are available when needed. Here's the critical path for outage inventory readiness:
12 Months Before: Strategic Planning
- Review previous outage lessons learned for inventory-related delays
- Identify long-lead-time items (>6 months) and initiate procurement
- Assess current inventory accuracy — if below 90%, schedule a wall-to-wall count before outage planning begins
6 Months Before: Scope and Materials
- Freeze major outage scope and develop work order packages
- Generate outage bill of materials from planned work scopes
- Compare BOM requirements against current inventory — identify gaps
- Order all items with lead times >90 days
3 Months Before: Verification and Staging
- Physical verification count of all outage-critical parts — confirm they're on hand and in proper condition
- Begin pre-staging materials by work order or craft area using spare parts management best practices
- Verify shelf-life dates on consumables (gaskets, adhesives, lubricants)
- Confirm receiving and inspection of all long-lead procurements
1 Month Before: Final Readiness
- Complete all pre-staging and kitting
- Conduct readiness review with maintenance, operations, and warehouse teams
- Establish outage material support protocols (after-hours access, expediting procedures)
- Set up dedicated outage laydown areas with controlled access
Inventory Management During the Outage
During the outage itself, inventory management shifts to rapid-response mode:
Ensure material support matches outage work hours (typically 24/7 operations)
Pre-authorized issue procedures for outage-critical work to minimize wait times
Update CMMS/EAM transactions daily — don't let paperwork stack up
Established protocols for items needed that weren't in the original scope (typically 10-15% of total material usage)
Track unused staged materials for prompt return to stock
Post-Outage Inventory Reconciliation
The 30 days following outage completion are critical for inventory integrity:
All unused pre-staged and kitted materials returned to proper storeroom locations within 14 days
Resolve all pending material transactions — receipts, issues, returns, transfers
Identify and root-cause any material that was consumed without proper documentation
Count all storeroom locations that had significant activity during the outage
Feed actual outage consumption data back into reorder point calculations
Document what worked, what didn't, and what to change for the next outage
The Role of Wall-to-Wall Counts in Outage Planning
Many energy facilities strategically time their annual wall-to-wall inventory count relative to their outage schedule:
Ensures accurate starting data for outage material planning. Most common for nuclear refueling outages.
Captures all inventory changes from the outage and resets the accuracy baseline. Common for fossil plant turnarounds.
Conducted during the least busy operational period, independent of outage timing.
For nuclear plants conducting 18–24 month refueling cycles, aligning the wall-to-wall count approximately 4–6 months before the outage provides the best balance of data accuracy and planning lead time.
Frequently Asked Questions
How far in advance should power plants plan outage material needs?
Material planning should begin 12 months before the outage for long-lead items and 6 months before for the full bill of materials. The bill of materials should be developed from the planned work scope and compared against verified inventory on hand.
What percentage of outage materials are typically emergent (unplanned)?
Industry experience shows that 10-15% of total outage material consumption comes from emergent or scope-growth work items. Effective outage planning includes contingency stock for commonly needed emergent items based on historical data.
Should we count inventory before or after a planned outage?
Both have value. A pre-outage count ensures accurate data for material planning. A post-outage count resets the accuracy baseline after high-volume transactions. Many facilities do a targeted count of outage-impacted areas within 30 days of completion.
Ready to Improve Your MRO Inventory Accuracy?
CPCON helps power plants and nuclear facilities optimize MRO inventory starting with accurate physical inventory services. Let us help you find the hidden value in your storerooms.
Related Resources
Wall-to-wall inventory count guide
Complete guide to planning and executing wall-to-wall inventory counts at energy facilities
MRO inventory management
Best practices for managing maintenance, repair, and operations inventory at power plants
Spare parts management
Strategic approaches to spare parts inventory for energy and nuclear facilities
Physical inventory services
Professional inventory counting services for power plants and industrial facilities
