B&W 177-FA
The B&W 177-FA is a Generation II pressurised water reactor from Babcock & Wilcox. 5 units are operating and 0 are under construction, out of 8 on record.
Babcock & Wilcox's 177-fuel-assembly plant, distinguished from every other American PWR by its once-through steam generators, which produce superheated steam and hold a far smaller water inventory on the secondary side. That small inventory is why a stuck-open relief valve at Three Mile Island Unit 2 escalated as fast as it did. GNPT's LLP and RLP suffixes are the lowered-loop and raised-loop arrangements. Oconee and Davis-Besse are the survivors.
| Vendor | Babcock & Wilcox |
|---|---|
| Reactor type | Pressurised water reactor (PWR) |
| Generation | II |
| Capacity range | 850–950 MWe gross |
| Also recorded as | B&W LLP (DRYAMB) B&W RLP (DRYAMB)in the source tracker |
| Coolant | Light water |
| Typical enrichment | 3–5% U-235 |
| United States | 8 units, 5 operating |
|---|
How long it took to build
Years from construction start to grid connection, for units with both dates on record. The median across 7 finished units is 6.1 years.
| Unit | Country | Started | Connected | Years |
|---|---|---|---|---|
| Oconee nuclear power plant 1 | United States | 1967 | 1973 | 5.5 |
| Oconee nuclear power plant 2 | United States | 1967 | 1973 | 6.1 |
| Three Mile Island nuclear power plant 1 | United States | 1968 | 1974 | 6.1 |
| Arkansas Nuclear One nuclear power plant 1 | United States | 1968 | 1974 | 5.9 |
| Oconee nuclear power plant 3 | United States | 1967 | 1974 | 6.9 |
| Crystal River nuclear power plant 3 | United States | 1968 | 1977 | 8.3 |
| Davis Besse nuclear power plant 1 | United States | 1970 | 1977 | 7.0 |
All B&W 177-FA units
| Unit | Country | Status | Gross MW | Online |
|---|---|---|---|---|
| Arkansas Nuclear One nuclear power plant 1 | United States | 903 | 1974 | |
| Davis Besse nuclear power plant 1 | United States | 925 | 1978 | |
| Oconee nuclear power plant 1 | United States | 891 | 1973 | |
| Oconee nuclear power plant 2 | United States | 891 | 1974 | |
| Oconee nuclear power plant 3 | United States | 900 | 1974 | |
| Crystal River nuclear power plant 3 | United States | Retired | 890 | 1977 |
| Three Mile Island nuclear power plant 1 | United States | Retired | 880 | 1974 |
| Three Mile Island nuclear power plant Unit 1 Repower | United States | Pre-construction | 880 | 2027 |
Sources
- B&W 177-FA, vendor documentation
- Global Nuclear Power Tracker, Global Energy Monitor, August 2026 release , CC BY 4.0 · retrieved 2026-09-06
How these sources are used, including the corrections applied on top of them and what is deliberately left blank · download the underlying data