County annual report · FIPS 25017
2015 Middlesex County, MA Power Outage Report
In 2015, customers in Middlesex County, MA went without power for an average of 2.7 hours, a total of 1.2M customer-hours (Massachusetts average 1.5 hours). That ranks 4th worst of 14 Massachusetts counties and 1002nd of 2,484 nationally.
Compared with MA, the US
Coverage line is EAGLE-I's share of Massachusetts customers tracked each year.
Biggest outages in Middlesex County, 2015
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | May 29, 2015 05:30 | May 30, 2015 03:30 | 22h | 44,646 | 62K |
| 2 | June 23, 2015 10:00 | June 26, 2015 12:00 | 3d 2h | 22,762 | 40K |
| 3 | August 4, 2015 18:30 | August 5, 2015 03:15 | 8h 45m | 22,430 | 107K |
| 4 | August 24, 2015 11:45 | August 26, 2015 00:45 | 1d 13h | 9,273 | 16K |
| 5 | September 30, 2015 01:45 | October 2, 2015 08:30 | 2d 6h | 8,763 | 22K |
| 6 | August 5, 2015 04:30 | August 8, 2015 07:45 | 3d 3h | 7,402 | 54K |
| 7 | June 16, 2015 05:45 | June 17, 2015 08:45 | 1d 3h | 7,071 | 27K |
| 8 | August 12, 2015 11:45 | August 13, 2015 07:00 | 19h 15m | 6,398 | 7,355 |
| 9 | July 23, 2015 05:15 | July 25, 2015 03:00 | 1d 21h | 5,316 | 20K |
| 10 | October 26, 2015 12:30 | October 27, 2015 07:00 | 18h 30m | 5,145 | 7,033 |
Outage episodes by size in 2015: 228 reached 100+ customers, 94 reached 1,000+ customers, 3 reached 10,000+ customers.
Utility reliability filed with the EIA
SAIDI (average outage time per customer) and SAIFI (average interruptions per customer) that utilities serving Middlesex County reported on EIA Form 861 for 2015, or their most recent earlier filing. Utility-wide figures, not county-specific.
| Utility | EIA year | SAIDI | SAIFI | SAIDI excl. major events | SAIFI excl. major events |
|---|---|---|---|---|---|
| Massachusetts Electric Co | 2014 | 2.4 hrs | 1.12 | 1.6 hrs | 0.96 |
| NSTAR Electric Company | 2015 | 1.6 hrs | 0.83 | 75 min | 0.76 |
| Unitil Energy Systems | 2015 | 1.9 hrs | 1.58 | 1.9 hrs | 1.58 |
| Fitchburg Gas & Elec Light Co | 2015 | 55 min | 1.02 | 55 min | 1.02 |
| Town of Reading - (MA) | 2015 | 64 min | 0.31 | 20 min | - |
| Massachusetts Bay Trans Authority | - | - | - | - | - |
| Town of Belmont - (MA) | - | - | - | - | - |
| Town of Concord - (MA) | - | - | - | - | - |
| Town of Groton - (MA) | - | - | - | - | - |
| Town of Hudson - (MA) | - | - | - | - | - |
| Town of Littleton - (MA) | - | - | - | - | - |
| Town of Wakefield - (MA) | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about n/a of Massachusetts's customers in 2015; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 434,426 customers (ORNL modeled county customer count), including major storm days. It is comparable across counties but is not the SAIDI a utility files.
- An outage event is a continuous stretch with customers out; counts at 100, 1,000 and 10,000+ use its peak.
- Years loaded: 2015–2025. Middlesex County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Middlesex County, MA annual power outage report, 2015, data as of Oct 3, 2026 02:41 UTC, sources: DOE EAGLE-I (https://eagle-i.doe.gov/); EAGLE-I modeled customer counts (MCC) (https://figshare.com/); EIA Form 861 (utility reliability) (https://www.eia.gov/electricity/data/eia861/). https://massoutage.com/reports/2015/massachusetts/middlesex-county