Updated July 2026: the Essential Edition and its companion database are refreshedGet it on Amazon→
NH — Power Infrastructure Updated 2026-07-17

New Hampshire

ISO-NE Data Center PPAs Transmission Constraints

1) Grid operator and market structure

  • Balancing authority / RTO-ISO: New Hampshire is within ISO New England’s regional transmission organization footprint; ISO-NE manages transmission service in the New England Balancing Authority Area, which spans Connecticut, Rhode Island, Massachusetts, New Hampshire, Vermont, and most of Maine. ISO New England, accessed 2026-07-17
  • Market structure: New Hampshire remains a retail-choice/restructured state under RSA 374-F. The statute identifies customer choice, default service as a safety-net service, and the principle that restructuring should not shift costs unfairly among customer classes. New Hampshire RSA 374-F:3, accessed 2026-07-17

2) Interconnection queue status (ISO-NE)

  • Queue/interconnection reforms: ISO-NE’s public interconnection guide routes new interconnection requests through FERC Order 2023 cluster windows; the guide states that the next complete-request window for the next cluster study is expected to run from October 5, 2026 to November 19, 2026. ISO New England Interconnection Process Guide, accessed 2026-07-17
  • Scope of public queue materials: ISO-NE’s interconnection process applies to generating facilities, elective transmission upgrades, and related administered-transmission-system connections; public queue materials do not provide a standardized New Hampshire data-center load queue or identify end-use customers by data-center status. ISO New England Interconnection Process Guide, accessed 2026-07-17
  • Large-load forecasting added in 2026: ISO-NE separately added a large-load forecast to the 2026-2035 CELT process. ISO-NE describes large loads as including data centers, crypto mining, industrial agriculture, and other localized high-demand uses, but its May 2026 public write-up is regional rather than New Hampshire-specific. ISO Newswire, 2026-05-18
  • FERC opened an ISO-NE large-load integration proceeding: On June 18, FERC issued an order to show cause in Docket EL26-72-000 requiring ISO-NE and the New England Participating Transmission Owners to justify their existing tariff or propose changes addressing large-load applications and studies, cost allocation and transparency, co-location and behind-the-meter generation, flexible-load transmission service, and generator interconnections serving nearby large loads. This is a live regional wholesale-transmission proceeding that applies in New Hampshire, not a New Hampshire retail-tariff order. FERC, 2026-06-18; FERC Order to Show Cause, Docket EL26-72-000, 2026-06-18

3) Ratepayer protection (large load / data centers)

  • General cost-shift principle: RSA 374-F:3 still supplies the baseline state-law principle: electric restructuring should benefit consumers equitably and costs should not be shifted unfairly among customers. New Hampshire RSA 374-F:3, accessed 2026-07-17
  • HB 1722 large-load tariff proposal failed: HB 1722 would have created a 20 MW-plus “large-energy-use facility” class covering NAICS 518210 computer processing, data processing centers, and web hosting services, with separate PUC-approved tariffs, minimum 10-year contracts, and express protections against shifting costs to other retail customers. The House killed the bill on March 12, 2026, so no HB 1722 large-load tariff framework was enacted. New Hampshire General Court HB1722 text, 2026-03-12; LegiScan HB1722, 2026-03-12
  • HB 1724 reporting proposal died: HB 1724 would have required annual utility reporting on transmission, wholesale-market, capacity, and generation-adequacy issues, including generation-capacity needs for data centers requiring 5 MW or more and recommendations to insulate ratepayers from data-center interconnection, transmission, rate-structure, and stranded-cost risks. After competing committee reports on February 25, the House took no further action before the June 4 sine-die adjournment, so the bill died. New Hampshire General Court HB1724 status, accessed 2026-07-17; NCSL legislative session calendar, 2026-06-12
  • HB 1739 incentive/grid-modernization proposal failed: HB 1739 would have conditioned data-center incentives on grid-modernization agreements requiring payment of direct interconnection costs, a share of network upgrades, non-gas generation procurement or financing, demand-response enrollment, and clawbacks. The House killed it on February 19, 2026. LegiScan HB1739 text, 2026-02-19; LegiScan HB1739, 2026-02-19
  • Federal cost-allocation review is pending: FERC’s June 18 order asks whether ISO-NE’s tariff prevents speculative requests, makes large loads pay study and network-upgrade costs, protects existing transmission customers from stranded costs, and supplies sufficient transparency. ISO-NE said it and the transmission owners planned to ask FERC by August 3 to hold the show-cause proceeding in abeyance for 90 days for stakeholder work, followed by a proposed November 16 tariff filing if FERC agreed; none of those steps had occurred by July 17. FERC Order to Show Cause, Docket EL26-72-000, 2026-06-18; ISO Newswire, 2026-06-29
  • No state retail large-load tariff found: The 2026 session produced proposed ratepayer-protection mechanisms, but the data-center-specific tariff/reporting bills above were not enacted. A review of the PUC docket book through July 17 did not identify a New Hampshire PUC order establishing a data-center-specific retail tariff or special rate class. New Hampshire PUC docket book, accessed 2026-07-17

4) Generation adequacy (projects likely to serve load)

  • Regional demand forecast: ISO-NE’s 2026 CELT summary projects regional net annual energy use rising from 116,679 GWh in 2026 to 127,660 GWh in 2035, with 50/50 net summer peak rising from 25,228 MW in 2026 to 26,849 MW in 2035 and 50/50 net winter peak rising from 20,483 MW in winter 2026/2027 to 26,411 MW in winter 2035/2036. ISO Newswire, 2026-05-01
  • Large-load contribution remains modest in ISO-NE’s 2026 forecast: ISO-NE reported that transmission-owner survey data showed two proposed New England large-load projects in formal study, with maximum combined demand of 285 MW. ISO-NE expected no effect before winter 2027/2028 and forecast those large loads to contribute about 110 MW to summer and winter peak demand in the 2030s, rising to about 130 MW in the 2040s; annual energy use from large loads was forecast around 800 GWh from 2030 to 2035, rising to about 1,000 GWh in the 2040s. ISO Newswire, 2026-05-18
  • Regional resource-adequacy report pending: FERC also directed each RTO/ISO to report on whether its region has adequate generation to meet expected large-load growth. ISO-NE said its informational report was due July 20, after this file’s cutoff date. FERC, 2026-06-18; ISO Newswire, 2026-06-29
  • New Hampshire-specific generation tied to data centers not identified: No public source reviewed through July 17 linked a New Hampshire data center to a new generator interconnection, a utility integrated-resource-plan update, or an executed data-center power purchase agreement. ISO New England Interconnection Process Guide, accessed 2026-07-17; New Hampshire PUC docket book, accessed 2026-07-17

5) Utility load forecasts / data center demand

  • Statewide and ISO-NE forecasts: ISO-NE’s 2026 public CELT summaries now include a large-load component, but the public summaries are regional and do not isolate a New Hampshire data-center forecast. ISO Newswire, 2026-05-01; ISO Newswire, 2026-05-18
  • Project-level demand disclosures remain thin: The FirstLight Bedford expansion announcement added approximately 25% more data center space, additional power and cooling infrastructure, and up to 100 additional racks, but it did not disclose MW demand. FirstLight, 2026-03-10
  • Nottingham proposal disclosed no MW: Thomas Moulton withdrew the conceptual Nottingham Business Park proposal on May 27, then said on July 3 that he might reintroduce it after further research. Public reporting supplied a roughly 200,000-square-foot building and an investment estimate in the tens of millions of dollars, but no MW load or utility service request. Granite Post, 2026-05-27; Yahoo News/Seacoastonline, 2026-07-03

6) Behind-the-meter (BTM), co-location, and direct procurement

7) Transmission constraints and upgrades

Notes on method and gaps

  • Priority was given to ISO-NE materials, New Hampshire statutes, New Hampshire General Court bill text, LegiScan status pages, operator announcements, and local reporting for project-specific facts.
  • Data-center-specific gaps remain material: no public NH PUC data-center retail-tariff docket, no project MW for FirstLight Bedford or Nottingham, no New Hampshire-specific public data-center load forecast, and no identified executed New Hampshire data-center PPA or interconnection agreement. The ISO-NE tariff response and resource-adequacy report were still pending at the July 17 cutoff. New Hampshire PUC docket book, accessed 2026-07-17; ISO Newswire, 2026-06-29