Reducing Condenser Inspection Costs Using Unmanned Aerial Vehicles (UAV) - MTA-MA-020-R1

Administrative Items
Date	March 2023
Functional Area Where Benefits Will Be Realized	Maintenance Quality Control
Reference Implementation Guidance	Remote Visual Inspections with Unmanned Aerial Systems (EPRI 3002013193) Unmanned Aircraft System (UAS) User’s Guide for Nuclear Power Plants: Implementation Guidance, Technologies and Applications, and Cost Savings Opportunities (EPRI 3002020913)
Industry SME	EPRI – Sam Johnson Contact: NuclearPlantMod@epri.com
Previous Implementation	Please contact EPRI for implementation examples and contacts.
Implementation Enablers	N/A
SWEEP Score	Cost – Level 3 – Utilizing the services of a vendor or an internal drone program will both cost less than $1 million. Savings – Level 1 – Savings are less than $1 million per year. Payback – Level 3 – Performing a condenser inspection with drones can produce an immediate payback with eliminated scaffolding costs, eliminated permit costs and reduced personnel usage alone. License readiness – Level 3 – This approach has already been implemented at nuclear power plants. Technology readiness – Level 3 – This approach has already been implemented at nuclear power plants. Implementation proficiency – Level 3 – The implementation and operation of drone technology does not require any special knowledge. Although indoor inspections do not require a Federal Aviation Administration (FAA) Part 107 license, drone pilots are required to have a Part 107 license for inspections in FAA airspace.
Applicability	All reactor types All geographic regions
Keywords	Drones; mobile unmanned systems; condenser inspections; maintenance; equipment reliability; unmanned aerial system (UAS); unmanned aerial vehicle (UAV) integration; personnel safety; remote visual inspection
Business Case Analysis Cross-Reference	N/A

Description

Condensers are used in nuclear power plants to convert steam from turbine exhaust into liquid water. To function properly, condensers require routine planned inspection and could also require emergent inspections for leaking valves or compromised piping. Traditional means of condenser inspections may expose personnel to dose and safety risks. Furthermore, unplanned inspections can require a plant derate or forced outage. The inspections also involve additional costs associated with obtaining scaffolding and permits. These costs and safety concerns can be reduced or eliminated with the use of unmanned aerial vehicles (UAV), also known as drones.

Drones can be used in a condenser inspection to reduce personnel dose and exposure, reduce inspection costs and time, and provide enhanced inspection methods. These drone inspections may even be conducted while a plant is at full power, saving on lost generation from derates or forced outages from traditional inspection methods. Drone inspection insights (e.g., discovering a leaking valve, inspecting pipes with thermography) may inform maintenance decisions that may lead to recovered thermal efficiency, reduced maintenance, or extended maintenance intervals. Drone technology functions with a remote operator and can provide both live and downloaded data feed insights. This MTA describes the benefits of using drone technology for condenser inspections.

Benefits

Benefits Estimate

Level 1 – Savings are expected to be less than $1 million per year and are achieved through reductions in scaffolding, permit and personnel costs ($30,000 to $100,000 in savings). Potential savings can be greater (> Level 1) from recovered thermal efficiency, reduced maintenance, or extended maintenance cycles depending on the results of the condenser inspection using drones.

Benefits Description

• Reduced or eliminated personnel dosage and exposure.
• Reduced planning and inspection costs from a reduction or elimination of scaffolding/permits/personnel.
• Reduced inspection time for both emergent and routine condenser inspections.
• Enhanced methods of condenser inspection. Traditional inspection tools can capture imagery but not with high‑resolution video and thermography simultaneously. Drones are capable of capturing data during condenser inspections using HD video, thermography, laser scanning and photogrammetry.
• Potential reduction in derated or outage conditions. Some inspections can be conducted while plant is at full power.
• Improved accessibility to traditionally difficult‑to‑reach inspection areas (e.g., steam space and areas under turbines).

Costs and Schedule

Cost

Level 3 – Implementing drone condenser inspections (either through an internal drone program or through a vendor) should be limited to $1 million or less. Using a drone vendor or implementation using an internal program are expected to be less than $100,000 per implementation. Vendor costs cover the inspection itself and an inspection report.

Schedule

A full condenser inspection typically takes 1‑2 days. The planning involved for a condenser inspection is plant specific but is less than six months.

Scope Context

Per inspection

This MQG assumes that the utility will either be using an external vendor or has an internal drone program.

Risks

• IT data risks are present when operating drones, such as automatic upload to an unsecure cloud. These risks can be mitigated by taking appropriate measures in selecting and setting up the drone inspections.
• There is a risk of generating foreign materials when conducting drone inspections inside the condenser. Proper training and appropriate usage and maintenance of the drone would mitigate this risk.
• Drones can be limited by battery life, thermal restrictions, and signal range.
• Standard project risks associated with implementing a new inspection method and potentially utilizing a contractor service at nuclear power plants.