Data last collected:
PowerPlantFactsEvidence report · prepared 19 October 2026https://powerplantfacts.com/entity/557
EIA plant 557
Preston · New London · CT
Tunnel
Operated by FirstLight Power Resources Services LLC
Published location
Where is Tunnel?
This locator uses the coordinates in the approved source record. It shows geographic context, not a site boundary, safety zone or property-risk area.
41.555425, -72.041829
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Capacity is not generation. Nameplate MW describes equipment; annual MWh describes recorded output. Proposed and retired units are not added to operating capacity.
Equipment mix
Operating capacity by technology
Grouped from this plant’s represented generator records. Use the CT plant index for regional peers.
See the evidence
Electricity output across the year
Monthly net generation shows the seasonal shape of this plant's represented output. A negative value is retained when the source reports net consumption.
11,382
21,340
31,440
41,280
51,380
6444
7114
88
95
100
110
12329
MWh net generation · 2024 final edition · EIA 923 represented operating rows. 12 of 12 supplied rows shown; 0 missing values omitted. Months with no reported numeric value are omitted, not treated as zero.
Read the chart as a table
| Record | MWh net generation |
|---|---|
| 1 | 1,382 |
| 2 | 1,340 |
| 3 | 1,440 |
| 4 | 1,280 |
| 5 | 1,380 |
| 6 | 444 |
| 7 | 114 |
| 8 | 8 |
| 9 | 5 |
| 10 | 0 |
| 11 | 0 |
| 12 | 329 |
2024 monthly net generation
| Month | Net generation |
|---|---|
| 1 | 1,382 MWh |
| 2 | 1,340 MWh |
| 3 | 1,440 MWh |
| 4 | 1,280 MWh |
| 5 | 1,380 MWh |
| 6 | 444 MWh |
| 7 | 114 MWh |
| 8 | 8 MWh |
| 9 | 5 MWh |
| 10 | 0 MWh |
| 11 | 0 MWh |
| 12 | 329 MWh |
Operating generators
| ID | Technology | Fuel | MW | Status |
|---|---|---|---|---|
| 10 | Petroleum Liquids | JF | 18.5 | SB |
| 1 | Conventional Hydroelectric | WAT | 1 | OP |
| 2 | Conventional Hydroelectric | WAT | 1 | OP |
Continue exploring
Similar-capacity plants in the same state
Identity, technology and limitations
EIA plant ID
557
Sector
IPP Non-CHP
Water source
Quinebaug
Data edition
2024-final
Use this record
Questions this evidence can answer
01What exactly is this record?
Use the name, place, date and identifiers above to confirm that you have the right Tunnel power plant: capacity and generation | PowerPlantFacts record.
02What does the evidence establish?
Read the reported values with their units, coverage dates and source notes. Keep observed facts separate from estimates or interpretation.
03What should I verify next?
Follow the primary-source links and check the limitations before using this evidence for a decision, comparison or citation.
A closer look at Tunnel
Variation in the published months
Across 12 numeric monthly generation entries, 3 has the highest recorded value (1,440 MWh) and 10, 11 the lowest (0 MWh). Their difference is 1,440 MWh. Missing months have not been treated as zero.
Reading the MW column
In the 3 numeric rows displayed in this table, MW ranges from 1 (1, 2) to 18.5 (10). The difference is 17.5 in the column's stated units. This summary covers the displayed rows and retains the table's period and scope.
Generator capacity in different operating conditions
| Generator ID | Technology | Nameplate MW | Summer MW | Winter MW | Minimum load MW |
|---|---|---|---|---|---|
| 1 | Conventional Hydroelectric | 1.0 | 0.8 | 1.1 | 0.3 |
| 10 | Petroleum Liquids | 18.5 | 16.5 | 21.8 | 5.0 |
| 2 | Conventional Hydroelectric | 1.0 | 0.8 | 1.1 | 0.3 |
EIA-860 2024 final source. Ratings describe capacity, not actual generation or availability. Missing ratings are not zero.
Source: US Energy Information Administration Form EIA-860 2024 plant and operable-generator workbooks; archive 2024. US EIA-authored information is generally public domain; cite EIA, preserve third-party exceptions, changes and no-endorsement context. Source-specific derived data.