?
Current reactor power level from the most recent NRC daily report.
0%
Power
OFFLINE (7 Days)
?
Days of continuous operation since the last outage ended. Ranked against all operating units.
1
Current Run
days
#92 of 95
Bottom Quartile
?
Longest recorded period of continuous operation between outages.
528
Record Run
days
#89 of 95
Bottom Quartile
?
Breaker-to-Breaker runs — continuous operation exceeding the cycle-adjusted threshold (455 days for this 18-month cycle unit) with no trips to 0% power.
9
B2B Runs
#17 of 87
Top Quartile
?
Lifetime capacity factor: average power level across all recorded days (100% = always at full power). Ranked against all NRC-tracked units.
90.6%
Capacity Factor
#43 of 95
Mid Quartile
?
Community rating score (Bayesian-adjusted). Based on 34 votes. Ranked against all rated facilities.
65.5
Rating
34 votes
#8 of 97
Top Quartile
?
Total NRC-reported scram events (emergency reactor shutdowns). Ranked fleet-wide — fewer scrams = better rank.
9
Scrams
#66 of 94
Mid Quartile
?
Years since commercial operation began. License remaining: 23.9 years.
35.6
Operating Age
years
23.9 yrs remaining
Capacity Factor (365-Day)
0%
Current
98.1%
365-Day Avg
#7
of 94 plants
Min: 0%
Max: 100%
7 days <80%
Scram History 9 events since 2011
Automatic and manual reactor scram (emergency shutdown) events reported to the NRC since 2011. Includes event dates, trip type, and average recovery time. Click the title to view the full fleet scram dashboard.
Outage Duration Trend
?Scheduled refueling outage durations over time. Green bars are below average, yellow near average, red above. Dashed line shows the plant's historical average. Shorter outages mean better execution.
Power History (12-Month)
?Daily power output as a percentage of rated capacity over the past 365 days. Green segments indicate full power (90%+), yellow shows reduced output, and red indicates significant power reductions or shutdowns.
Outage Days by Year
?Total days spent in outage each year, split by scheduled refueling (blue) and forced/unplanned (red). Lower totals indicate better reliability and outage execution. Hover for details.
Facility Statistics
Key performance and lifecycle metrics calculated from NRC operational data. Includes operating age, construction timeline, capacity factor, efficiency, generation totals, and reliability records.
Lifecycle & Tenure
Operating Age: 35.6 Yrs
Build Time: 14.1 Yrs
Lic. Remaining: 23.9 Yrs
Production & Power
Lifetime CF: 90.6%
Efficiency: 34.3%
Generated: 270.5 TWh
Reliability & Outages
Record Run: 528 Days
Refuelings: 22
Ratings 34 votes
Community ratings from NukeWorker members. Vote to share your experience working at this facility. Score uses a Bayesian average that accounts for vote count — facilities with few votes are pulled toward the fleet average, so rankings reflect confidence, not just raw percentages.
Above Average
22 (64%)
Average
10 (29%)
Below Average
2 (5%)
Facility Map
Interactive satellite map showing the facility's geographic location. Marker color indicates current status: green for online, red for offline, orange for reduced power. Click the header to open in Google Maps satellite view.
42.899, -70.8509
Location & Contact
Physical address, phone number, and website for this facility. Use the directions link to get driving directions via Google Maps.
Phone:
(516) 929-8300
Per Diem Rates FY 2026
Per diem covers lodging and meals & incidental expenses (M&IE) for government and contractor travel near this facility. Rates are from GSA for FY 2026. Lodging rates vary by month — click "Show Monthly" to see the breakdown.
$129
Lodging/Night
$129–$192 range
$74
M&IE/Day
$203
Total/Day
Portsmouth, Rockingham County, NH
Jobs in NH 2 active
Active nuclear industry job listings in NH from the NukeWorker job board. Click a job title for full details, or click the header to search all jobs in this state.
Photos
Photos of this facility from the NukeWorker photo gallery. Click the header or any photo to browse the full album.
Breaker-to-Breaker Runs 9 runs
Breaker-to-breaker runs measure continuous operation between refueling outages using a cycle-adjusted threshold (90% of cycle length minus RFO duration). An active streak means the unit has been running continuously since the last refueling with no trips to 0% power.
525
Best Run (days)
2014-04-24 → 2015-10-01
505
Avg Run (days)
All Runs
| 2021-11-05 | 2023-04-01 | 512 days |
| 2020-06-11 | 2021-10-02 | 478 days |
| 2018-10-28 | 2020-04-01 | 521 days |
| 2017-05-01 | 2018-10-01 | 518 days |
| 2014-04-24 | 2015-10-01 | 525 days |
| 2012-10-30 | 2014-04-01 | 518 days |
| 2009-12-17 | 2011-04-01 | 470 days |
| 2008-05-08 | 2009-10-01 | 511 days |
| 2002-05-31 | 2003-10-04 | 491 days |
Ownership & Construction
The utility or company that owns and operates the facility, the architect-engineer responsible for plant design, and the primary construction contractor. Click names to view all facilities by that entity on the map.
Technical Specs
Reactor design specifications including type (PWR/BWR), containment design, nuclear steam supply system manufacturer, thermal and electrical power ratings, and current operational status.
Reactor Type:
PWR
Containment:
PWR-DRYAMB
NSS Supplier:
WEST 4LP
Thermal Power:
3648 MWt
Net Capacity:
1250 MWe
Efficiency:
34.3%
Status:
Operating
Licensing
NRC licensing history including docket number, license type and number, construction permit date, operating license issuance, commercial operation date, license renewal, and expiration date.
Docket #:
05000443
License #:
NPF-86
License Type:
OL-FP
Const. Permit:
1976-07-07
Operating Lic:
1990-03-15
Commercial Op:
1990-08-19
License Renewed:
2019-03-12
License Exp:
2050-03-15