Massachusetts natural gas case study, Worcester, Massachusetts. October 2026

Worcester-area natural gas capacity: the utility's plan projects a design day deficiency every year, mostly on the pipeline that serves Worcester

NSTAR Gas told the Massachusetts Department of Public Utilities (the Department) in July 2024 that its base-case design day is short of its resources in every one of its five forecast years, by 23.5 BBtu in 2024-25 and 46.8 BBtu in 2028-29 for its four divisions together, and that for the first four years the deficiency is mostly on the Tennessee Gas Pipeline system that serves Worcester. The Department found in July 2025 that NSTAR Gas has adequate supplies and can reasonably be expected to secure incremental supplies under design conditions.

88 EDDsDesign day standard for NSTAR Gas's Worcester and Framingham divisions, per the Department's order
23.5 BBtuNSTAR Gas's base-case design day deficiency for 2024-25, four divisions together, per NSTAR Gas
46.8 BBtuThe same deficiency for 2028-29, four divisions together, per NSTAR Gas
8.2%Winter service supplies as a share of 2028-29 design day sendout, calculated from NSTAR Gas figures, four divisions

By Sam Strong, Vice President of Business Development, Discovery Energy. Technical review by Tara Dugger, Chief Operating Officer. Updated .

Metro used: the Worcester, MA metropolitan statistical area, as delineated in OMB Bulletin No. 23-01 (July 21, 2023): Worcester County, Massachusetts. The gas distribution utility identified in the record for Worcester is NSTAR Gas Company, doing business as Eversource Energy (NSTAR Gas), whose service territory includes a Worcester division served by Tennessee Gas Pipeline. NSTAR Gas's plan gives most of its figures for its four divisions together, so those figures are system-wide and labeled as such. Eversource Gas Company of Massachusetts (EGMA) was checked and its plan names no Worcester division. Other gas utilities in Worcester County are not established in the record.1

Key takeaways

  • NSTAR Gas said in its July 2024 plan that its design day standard is 1:50, and the Department's July 2025 order records a design day standard of 88 equivalent degree days for the Worcester and Framingham divisions.2
  • NSTAR Gas's base-case design day sendout for its four divisions together is 544.8 BBtu in 2024-25 and 568.1 BBtu in 2028-29, and the plan fills the gap between resources and the design day with winter service supplies of 23.5 BBtu in 2024-25 and 46.8 BBtu in 2028-29.3
  • NSTAR Gas said the design day deficiency is mostly on the Tennessee Gas Pipeline system for the first four years; Worcester is served by that pipeline.3
  • The Department found in its July 2025 order that NSTAR Gas has established that it possesses adequate supplies to meet its expected sendout requirements, and that it can reasonably be expected to secure incremental supplies that will satisfy its projected requirements under design conditions.4
  • NSTAR Gas said it has contracts providing 40,000 MMBtu per day of Tennessee Gas Pipeline capacity to its largest take station on that system, at Upland Street in Worcester, and that it still lacks sufficient long haul pipeline capacity on that system.3
  • A search of official records found no planned natural gas-fired generator in Worcester County in EIA's September 2026 inventory, and no pipeline notice naming the county among Federal Energy Regulatory Commission notices since January 1, 2025.7

Which parts of the record fall inside the Worcester metro?

NSTAR Gas said its service territory consists of four major operating divisions: Worcester, Framingham, Cambridge and New Bedford. It said Worcester is served by Tennessee Gas Pipeline, and that its Hopkinton LNG facility sits on the boundary between its Framingham division and its Worcester division.1

Where Item in NSTAR Gas's plan
Inside the metro The Worcester division, served by Tennessee Gas Pipeline, including its Upland Street take station in Worcester
Outside the metro, system context The four-division totals (design day sendout, deficiency); the Framingham, Cambridge and New Bedford divisions served by Algonquin; the Constellation LNG contract
Unclear The towns in the Worcester division; other gas utilities in Worcester County; Windham County, Connecticut (outside the OMB county list)

NSTAR Gas's divisions and figures, by whether they fall inside the Worcester metro (OMB delineation). Source: Forecast and Supply Plan, D.P.U. 24-106.1

System context: only the location of the deficiency, mostly the Tennessee Gas Pipeline system, points to the Worcester division. The plan does not give a Worcester-only design day or deficiency.

How much spare gas capacity does Worcester have on the coldest day?

Major natural gas pipelines serving Worcester N Tennessee Gas Pipeline Tennessee Gas Pipeline Algonquin Algonquin Other transmission pipelines in the EIA layer (interstate and intrastate; unlabeled) Pipeline named in a verified claim on this page (labeled, one color each) Metro counties (boundary used on this page) Major highways (for orientation)
Figure 1. Major natural gas pipelines serving Worcester. Simplified, not to scale. Discovery Energy illustration from EIA and U.S. Census data. Coastline, lakes and highways: Natural Earth (public domain).

NSTAR Gas plans for a 1:50 design day. For its four divisions together, its base-case design day resources fall short of the design day in each of the five forecast years, and the plan fills the gap with winter service supplies.23

Gas year Design day sendout (BBtu) Winter service supplies filling the gap (BBtu)
2024-25 544.8 23.5
2025-26 550.2 28.9
2026-27 556.2 34.9
2027-28 562.1 40.8
2028-29 568.1 46.8

NSTAR Gas's base-case design day adequacy, BBtu, four divisions together, per NSTAR Gas. Source: Forecast and Supply Plan, D.P.U. 24-106, Figure 47.3

Calculated from NSTAR Gas figures for the same year, the winter service supplies are 4.3% of the design day sendout in 2024-25 and 8.2% in 2028-29 (illustrative; the plan states no share).3

NSTAR Gas said for the first four years the deficiency is mostly on the Tennessee Gas Pipeline system. Its SENDOUT design-weather run for 2024-25 shows system unserved of zero, a modeled result for its whole system.3

The plan says it maintains a design hour criterion, the peak hour on a design day, which can vary throughout the system; it gives no hourly requirement and no take-station balance, so spare capacity at the Worcester gate stations is not established here.3

What is driving new natural gas demand?

The passages of NSTAR Gas's plan read for this page name no large new gas load in Worcester County.1

A search of other official records found no further documented gas load in Worcester County: EIA's September 2026 generator inventory lists no planned natural gas-fired generator there, and a search of Federal Register notices of the Federal Energy Regulatory Commission since January 1, 2025 found no pipeline notice naming the county.7

Are upgrades arriving in time?

NSTAR Gas said the deficiency would be addressed with additional supplies. Its plan says, in its high growth case discussion, that the Tennessee Gas Pipeline deficiencies would be purchased at either Dracut or Everett and transported on the pipeline's Zone 6 to Zone 6 capacity, and that it plans to address its shortfall with supplies from Constellation LNG at Everett Marine Terminal. The record shows no contract for the incremental winter supplies.3

The Constellation LNG peaking contract approved on May 17, 2024 has a total maximum daily quantity of 15,000 Dth and runs through May 31, 2030; its volumes serve the New Bedford, Plymouth and Cambridge areas or the pipeline at Everett, not Worcester directly.3

The Department directed NSTAR Gas to file its next forecast and supply plan by July 17, 2026. That later plan is not in the record read for this page.4

Winter and market context

Context only, as of October 2026. It does not set the outlook level and makes no prediction of outages. Its sources are listed separately under Market and weather sources and are refreshed on the publication date.

NOAA's Climate Prediction Center said on October 15, 2026 that its November 2026 to January 2027 discussion puts the highest odds of warmer than normal conditions over, among other areas, the interior Northeast, a discussion that names regions and not counties, and that the probability of at least a strong El Nino continuing through January to March 2027 is 80%.B1 The U.S. Energy Information Administration (EIA) said on October 6, 2026 that it expects U.S. natural gas inventories to enter the winter heating season 2% above the previous five-year average, and that prolonged periods of cold weather could increase withdrawals beyond its forecast.A1A2 EIA lists U.S. liquefied natural gas gross exports of 15 billion cubic feet per day in 2025, 18 in 2026 and 19 in 2027.A1 These are national and regional facts, not statements about the utility's system, and none of them is used to set the outlook on this page.

What is the outlook for Worcester gas capacity through 2029?

Discovery Energy rates the outlook for Worcester-area natural gas capacity through 2029 as Elevated (confidence: Medium): NSTAR Gas's own plan projects a design day deficiency in every forecast year, mostly on the pipeline that serves Worcester, filled by winter service supplies with no contract shown in the record, though the Department found adequate supplies. Documented risk factors: none beyond the base level. Three developments would change the assessment: NSTAR Gas's next forecast and supply plan (due July 2026, not yet read) and the Department's order on it; any contract for the incremental winter supplies on the Tennessee Gas Pipeline system; the end of the Constellation LNG contract on May 31, 2030.

Outlook levels, from least to most concern: Stable, Watch, Elevated, High, Severe. Levels describe the public record of capacity and supply risk; confidence is reported separately. They are qualitative assessments, not forecasts of outages.

What should Worcester-area facilities check now?

  • Tariffs and charges, through a utility audit. Confirm each account is on the right rate class and tariff, and that riders, demand charges and capacity-related charges are billed correctly. Over 70% of the clients Discovery Energy has audited were billed incorrectly. An audit verifies tariffs and charges and recovers overcharges before winter costs rise.
  • Which utility and which service. Confirm which gas utility serves each site and whether it takes firm or interruptible service, and read the interruption terms in the current approved tariff.
  • Backup plans and fuel. Check that alternate-fuel and curtailment plans are current and feasible, and that fuel inventories and resupply arrangements are in place before December.
  • Upcoming proceedings. Track NSTAR Gas's 2026 forecast and supply plan and the Department's order on it.

Frequently asked questions

Will Worcester businesses face natural gas shortages this winter?

The record does not show a shortage. NSTAR Gas projects a design day deficiency in each of its five forecast years, filled in its plan by winter service supplies, and the Department found it has adequate supplies and can reasonably be expected to secure incremental supplies. This page makes no prediction about outages.

Is there spare gas capacity in the Worcester area on the coldest day?

NSTAR Gas's plan shows a design day deficiency of 23.5 BBtu in 2024-25 for its four divisions together, mostly on the Tennessee Gas Pipeline system that serves Worcester. The plan gives no Worcester-only margin.

Which utility serves Worcester, and does the EGMA plan cover it?

The saved NSTAR Gas plan names a Worcester division served by Tennessee Gas Pipeline. EGMA's plan names the Brockton, Lawrence and Springfield divisions and no Worcester division. Other utilities in Worcester County are not established.

Did the Department approve NSTAR Gas's plan?

The Department's July 2025 order found that NSTAR Gas has adequate supplies for its expected requirements and can reasonably be expected to secure incremental supplies under design conditions, and it directed the next plan by July 17, 2026.

Is a data center or power plant driving gas demand in Worcester?

The record does not show one. EIA's September 2026 inventory lists no planned gas-fired generator in Worcester County and no Federal Energy Regulatory Commission pipeline notice names it.

Related case studies

Discovery Energy publishes gas capacity case studies for other metros, using the same method and outlook scale.

All gas capacity ratings by U.S. metro

Understand your capacity exposure

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Notes

  1. NSTAR Gas Company d/b/a Eversource Energy, Forecast and Supply Plan, Massachusetts DPU D.P.U. 24-106 (filed July 19, 2024), service territory pages and PDF 93 (Hopkinton LNG and the Worcester division). Utility statements. Metro county from metro_counties.csv; classification in worcester_metro_classification.csv. EGMA (D.P.U. 23-125) checked and excluded: its saved plan has no Worcester text. Windham County, Connecticut: not in the OMB 2023 county list for CBSA 49340; Yankee Gas (Eversource Connecticut) serves part of Windham County (a search lead, not saved); Connecticut Natural Gas's website timed out on its robots check and was not fetched. [WOR-01 to WOR-03] ↩
  2. Same plan, PDF 14 (design day standard) and Massachusetts DPU, Order on D.P.U. 24-106 (July 14, 2025), PDF 7 and 36. Department finding. [WOR-04 to WOR-06] ↩
  3. Same plan, PDF 93, 98, 101, 103, 104, 106 and 377 (Figure 47 and related text; SENDOUT run). Shares run by code (worcester_calculations.csv; illustrative): 23.5 divided by 544.8 is 4.3% and 46.8 divided by 568.1 is 8.2%; the EMT contract's 15,000 Dth per day is 2.75% of the 2024-25 design day. The document was saved for the Boston case study from a manual DPU download. [WOR-07 to WOR-12, WOR-15 to WOR-20, WOR-30, WOR-31] ↩
  4. Massachusetts DPU, Order on D.P.U. 24-106, PDF 35 and 36. Department finding. [WOR-13, WOR-14, WOR-21] ↩
  5. Not established, and left out of the page: supply events since January 1, 2020 affecting the Worcester division in an official record (none found); delivery-point utilization from pipeline postings (Tennessee Gas Pipeline's postings were not captured; next capture about March 2027); cost allocation among customer classes and the interruption sequence (the tariff was not read); the towns in the Worcester division and whether Unitil, National Grid or another utility serves part of Worcester County; NSTAR Gas's 2026 forecast and supply plan, due July 17, 2026.
  6. The Constellation LNG contract and the Algonquin-system items belong to other NSTAR Gas divisions; they are system context and do not set the outlook.
  7. EIA-860M inventory for September 2026 (Planned sheet, operator-reported planned dates), filtered to Worcester County by code, and a Federal Register search of FERC notices since January 1, 2025 by county phrase, both computed by code. A notice that spells a place differently would be missed. [WOR-22, WOR-23] ↩
  8. R3 not established, and left out of the claims (searches run: EIA-860M, a Federal Register search of FERC notices by county, and the plan text): state air permit records (Massachusetts Department of Environmental Protection), ISO New England queue entries by county, FERC eLibrary filings, none of which a script could save; news reports are leads only and are not claimed.

Market and weather sources

Public web sources saved and hashed on October 25, 2026. They are context, separate from the regulatory record cited in the Notes. The Climate Prediction Center issues its seasonal outlook once each month near mid-month; this section is refreshed on the publication date.

  1. A1. U.S. Energy Information Administration, press release, "EIA expects a mixed picture for winter fuel costs this year," October 6, 2026. Link ↩
  2. A2. U.S. Energy Information Administration, Short-Term Energy Outlook, October 2026 (natural gas storage). Link ↩
  3. B1. NOAA Climate Prediction Center, Prognostic Discussion for Long-Lead Seasonal Outlooks, issued October 15, 2026. Link ↩

Sources

  1. NSTAR Gas Company d/b/a Eversource Energy, Forecast and Supply Plan, D.P.U. 24-106 (filed July 19, 2024). Massachusetts Department of Public Utilities file room (manual download).
  2. Massachusetts Department of Public Utilities, Order on D.P.U. 24-106 (July 14, 2025), and Joint Order on D.P.U. 25-133 and 25-134 (January 30, 2026). Massachusetts Department of Public Utilities file room (manual download).
  3. Office of Management and Budget, OMB Bulletin No. 23-01, Revised Delineations of Metropolitan Statistical Areas, Micropolitan Statistical Areas, and Combined Statistical Areas, July 21, 2023.
  4. U.S. Energy Information Administration, EIA-860M Preliminary Monthly Electric Generator Inventory, September 2026. Link
  5. Federal Register, API search of Federal Energy Regulatory Commission notices by county. Link