Nuclear fuel transport: Technology advances
New railcars and packages for higher-enriched fuels
What this tab covers The newest technologies in service or close to adoption, what each improves, and how the main options compare.New railcars and packages are being built for US spent fuel and for the higher-enriched fuels that small and advanced reactors need.
Latest advances
Atlas railcar in service (certified) · 202412-axle railcar for heavy spent-fuel casks, approved under AAR standard S-20433
Improves: Moves casks up to 218 t by rail across the US
Fortis railcar demonstration · 2025 onward8-axle railcar for lighter casks3
Improves: Could be operating before 2030
DN30-X package with 30B-10 cylinder being deployed · 2023 licence, 2025 serial productionOverpack with borated steel rods for UF6 enriched up to 10%5
Improves: Carries LEU+ fuel beyond the 5% limit of standard 30B cylinders
HALEU (up to 20%) packages being deployed (TRISO); development (UF6) · 2023 licence; 2025 statusNAC's Optimus-L package is licensed for HALEU in TRISO fuel form; packages for HALEU as UF6 are not yet on the market511
Improves: Lack of cylinders delayed a 900 kg HALEU UF6 delivery in 2024
2025 edition of IAEA SSR-6 (Rev. 2) in service · Published December 2025Revised international transport regulations: new A1/A2 limits with a 10-year transition, ageing checks for package designs6
Improves: Updates the rules all national regulators copy
New dedicated ships in service · 2021CNNC's Xin An Ji Xiang (delivered 2021); Rosatomflot's Rossita1
Improves: Adds sea capacity in China and Arctic Russia
Comparing the options
| Option | Efficiency | Cost | Capacity or distance | Maturity |
|---|---|---|---|---|
| Road (truck)1 | Negligible energy use | Lowest per trip; no public tariff | About 6 t of fresh fuel per truck | mature |
| Rail3 | Negligible energy use | Atlas development about USD 33 million | Casks up to 218 t | mature (US system being re-established) |
| Dedicated sea vessel1 | Negligible energy use | Rossita ship EUR 70 million | 12 to 24 casks per voyage | mature |
| Air (Type C)1 | Higher energy use, small loads | No public figure found | Small high-activity consignments | mature, rarely used |
Fresh fuel moves mostly by truck because it is light and low in radioactivity. Spent fuel goes by rail or ship because loaded casks exceed road weight limits. Air transport is reserved for small, urgent, high-value consignments. The main frontier is not new vehicles but new packages for fuels enriched above 5%.
Sources
- Transport of Radioactive Materials (updated August 2026) World Nuclear Association, 2026
- DOE-designed railcar cleared for use World Nuclear News, 2024
- Orano begins production of LEU+ transport cylinders World Nuclear News, 2025
- SSR-6 (Rev. 2): Regulations for the Safe Transport of Radioactive Material, 2025 Edition World Nuclear Transport Institute (reporting IAEA), 2025
- NRC approves HALEU transport package World Nuclear News, 2024