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eversource.jpg
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549
FORM10-K
ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT OF 1934

For the fiscal year ended
December 31, 2023
or
TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE     
SECURITIES EXCHANGE ACT OF 1934

For the transition period from ____________ to ____________

Registrant; State of Incorporation; Address; Telephone Number;
Commission File Number; and I.R.S. Employer Identification No.

EVERSOURCE ENERGY
(a Massachusetts voluntary association)
300 Cadwell Drive, Springfield, Massachusetts 01104
Telephone: (800) 286-5000
Commission File Number: 001-05324
I.R.S. Employer Identification No. 04-2147929


THE CONNECTICUT LIGHT AND POWER COMPANY
(a Connecticut corporation)
107 Selden Street, Berlin, Connecticut 06037-1616
Telephone: (800) 286-5000
Commission File Number: 000-00404
I.R.S. Employer Identification No. 06-0303850


NSTAR ELECTRIC COMPANY
(a Massachusetts corporation)
800 Boylston Street, Boston, Massachusetts 02199
Telephone: (800) 286-5000
Commission File Number: 001-02301
I.R.S. Employer Identification No. 04-1278810


PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE
(a New Hampshire corporation)
Energy Park
780 North Commercial Street, Manchester, New Hampshire 03101-1134
Telephone: (800) 286-5000
Commission File Number: 001-06392
I.R.S. Employer Identification No. 02-0181050
Securities registered pursuant to Section 12(b) of the Act:
Title of each classTrading Symbol(s)Name of each exchange on which registered
Common Shares, $5.00 par value per shareESNew York Stock Exchange

Indicate by check mark if the registrants are well-known seasoned issuers, as defined in Rule 405 of the Securities Act.
 YesNo
 

Indicate by check mark if the registrants are not required to file reports pursuant to Section 13 or Section 15(d) of the Act.
 YesNo
 

Indicate by check mark whether the registrants (1) have filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrants were required to file such reports), and (2) have been subject to such filing requirements for the past 90 days.
 YesNo
 

Indicate by check mark whether the registrants have submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrants were required to submit such files).
 YesNo
 

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.
Eversource EnergyLarge accelerated filerAccelerated
filer
Non-accelerated
filer
Smaller reporting companyEmerging growth company
The Connecticut Light and Power CompanyLarge accelerated filerAccelerated
filer
Non-accelerated filerSmaller reporting companyEmerging growth company
NSTAR Electric CompanyLarge accelerated filerAccelerated
filer
Non-accelerated filerSmaller reporting companyEmerging growth company
Public Service Company of New HampshireLarge accelerated filerAccelerated
filer
Non-accelerated filerSmaller reporting companyEmerging growth company

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ¨

Indicate by check mark whether the registrant has filed a report on and attestation to its management's assessment of the effectiveness of its internal control over financial reporting under Section 404(b) of the Sarbanes-Oxley Act (15 U.S.C. 7262(b)) by the registered public accounting firm that prepared or issued its audit report.

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant’s executive officers during the relevant recovery period pursuant to §240.10D-1(b). ☐

Indicate by check mark whether the registrants are shell companies (as defined in Rule 12b-2 of the Exchange Act):
 YesNo
Eversource Energy
The Connecticut Light and Power Company
NSTAR Electric Company
Public Service Company of New Hampshire

The aggregate market value of Eversource Energy's Common Shares, $5.00 par value, held by non-affiliates, computed by reference to the price at which the common equity was last sold, or the average bid and asked price of such common equity, as of the last business day of Eversource Energy's most recently completed second fiscal quarter (June 30, 2023) was $24,734,207,777 based on a closing market price of $70.92 per share for the 348,762,095 common shares outstanding held by non-affiliates on June 30, 2023. 

Indicate the number of shares outstanding of each of the registrant's classes of common stock, as of the latest practicable date:
Company - Class of StockOutstanding as of January 31, 2024
Eversource Energy
Common Shares, $5.00 par value
349,687,183 shares
The Connecticut Light and Power Company
Common Stock, $10.00 par value
6,035,205 shares
NSTAR Electric Company
Common Stock, $1.00 par value
200 shares
  
Public Service Company of New Hampshire
Common Stock, $1.00 par value
301 shares

Eversource Energy holds all of the 6,035,205 shares, 200 shares, and 301 shares of the outstanding common stock of The Connecticut Light and Power Company, NSTAR Electric Company and Public Service Company of New Hampshire, respectively.

The Connecticut Light and Power Company, NSTAR Electric Company and Public Service Company of New Hampshire each meet the conditions set forth in General Instruction I(1)(a) and (b) of Form 10-K, and each is therefore filing this Form 10-K with the reduced disclosure format specified in General Instruction I(2) of Form 10‑K.  

Eversource Energy, The Connecticut Light and Power Company, NSTAR Electric Company and Public Service Company of New Hampshire each separately file this combined Form 10-K.  Information contained herein relating to any individual registrant is filed by such registrant on its own behalf.  Each registrant makes no representation as to information relating to the other registrants.

Documents Incorporated by Reference

Portions of the Eversource Energy and Subsidiaries 2022 combined Annual Report on Form 10-K and portions of the Proxy Statement relating to the Annual Meeting of Shareholders to be held on May 1, 2024, are incorporated by reference into Parts II and III of this Report.



GLOSSARY OF TERMS

The following is a glossary of abbreviations and acronyms that are found in this report:

Current or former Eversource Energy companies, segments or investments:
Eversource, ES or the CompanyEversource Energy and subsidiaries
Eversource parent or ES parentEversource Energy, a public utility holding company
ES parent and other companiesES parent and other companies are comprised of Eversource parent, Eversource Service, and other subsidiaries, which primarily includes our unregulated businesses, HWP Company, The Rocky River Realty Company (a real estate subsidiary), the consolidated operations of CYAPC and YAEC, and Eversource parent's equity ownership interests that are not consolidated
CL&PThe Connecticut Light and Power Company
NSTAR ElectricNSTAR Electric Company
PSNHPublic Service Company of New Hampshire
PSNH FundingPSNH Funding LLC 3, a bankruptcy remote, special purpose, wholly-owned subsidiary of PSNH
NSTAR GasNSTAR Gas Company
EGMAEversource Gas Company of Massachusetts
Yankee GasYankee Gas Services Company
AquarionAquarion Company and its subsidiaries
HEECHarbor Electric Energy Company, a wholly-owned subsidiary of NSTAR Electric
Eversource ServiceEversource Energy Service Company
North East OffshoreNorth East Offshore, LLC, an offshore wind business being developed jointly by Eversource and Denmark-based Ørsted
CYAPCConnecticut Yankee Atomic Power Company
MYAPCMaine Yankee Atomic Power Company
YAECYankee Atomic Electric Company
Yankee CompaniesCYAPC, YAEC and MYAPC
Regulated companiesThe Eversource regulated companies are comprised of the electric distribution and transmission businesses of CL&P, NSTAR Electric and PSNH, the natural gas distribution businesses of Yankee Gas, NSTAR Gas and EGMA, Aquarion’s water distribution businesses, and the solar power facilities of NSTAR Electric
Regulators and Government Agencies:
BOEM
U.S. Bureau of Ocean Energy Management
DEEPConnecticut Department of Energy and Environmental Protection
DOEU.S. Department of Energy
DOERMassachusetts Department of Energy Resources
DPUMassachusetts Department of Public Utilities
EPAU.S. Environmental Protection Agency
FERCFederal Energy Regulatory Commission
ISO-NEISO New England, Inc., the New England Independent System Operator
MA DEPMassachusetts Department of Environmental Protection
NHPUCNew Hampshire Public Utilities Commission
PURAConnecticut Public Utilities Regulatory Authority
SECU.S. Securities and Exchange Commission
Other Terms and Abbreviations:
ADITAccumulated Deferred Income Taxes
AFUDCAllowance For Funds Used During Construction
AOCIAccumulated Other Comprehensive Income
AROAsset Retirement Obligation
BcfBillion cubic feet
CfDContract for Differences
CWIPConstruction Work in Progress
EDCElectric distribution company
EDITExcess Deferred Income Taxes
EPSEarnings Per Share
ERISAEmployee Retirement Income Security Act of 1974
i


ESOPEmployee Stock Ownership Plan
Eversource 2022 Form 10-KThe Eversource Energy and Subsidiaries 2022 combined Annual Report on Form 10-K as filed with the SEC
FitchFitch Ratings, Inc.
FMCCFederally Mandated Congestion Charge
GAAPAccounting principles generally accepted in the United States of America
GWhGigawatt-Hours
IPPIndependent Power Producers
ISO-NE TariffISO-NE FERC Transmission, Markets and Services Tariff
kVKilovolt
kVaKilovolt-ampere
kWKilowatt (equal to one thousand watts)
LNGLiquefied natural gas
LPGLiquefied petroleum gas
LRSSupplier of last resort service
MGMillion gallons
MGPManufactured Gas Plant
MMBtuMillion British thermal units
MMcfMillion cubic feet
Moody'sMoody's Investors Services, Inc.
MWMegawatt
MWhMegawatt-Hours
NETOsNew England Transmission Owners (including Eversource, National Grid and Avangrid)
OCIOther Comprehensive Income/(Loss)
ORECOffshore Wind Renewable Energy Certificate
PAMPension and PBOP Rate Adjustment Mechanism
PBOPPostretirement Benefits Other Than Pension
PBOP PlanPostretirement Benefits Other Than Pension Plan
Pension PlanSingle uniform noncontributory defined benefit retirement plan
PPAPower purchase agreement
PPAM
Pole Plant Adjustment Mechanism
RECsRenewable Energy Certificates
Regulatory ROEThe average cost of capital method for calculating the return on equity related to the distribution business segment excluding the wholesale transmission segment
ROEReturn on Equity
RRBsRate Reduction Bonds or Rate Reduction Certificates
RSUsRestricted share units
S&PStandard & Poor's Financial Services LLC
SERPSupplemental Executive Retirement Plans and non-qualified defined benefit retirement plans
SSStandard service
UIThe United Illuminating Company
VIEVariable Interest Entity

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EVERSOURCE ENERGY AND SUBSIDIARIES
THE CONNECTICUT LIGHT AND POWER COMPANY
NSTAR ELECTRIC COMPANY AND SUBSIDIARY
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES

2023 FORM 10-K ANNUAL REPORT

TABLE OF CONTENTS
 Page
PART I 
Item 1.
Item 1A.
Item 1B.
Item 1C.
Item 2.
Item 3.
Item 4.
   
PART II 
Item 5.
Item 6.
Item 7.
Item 7A.
Item 8.
Item 9.
Item 9A.
Item 9B.
   
PART III 
Item 10.
Item 11.
Item 12.
Item 13.
Item 14.
   
PART IV 
Item 15.
Item 16.
E-9


iii


EVERSOURCE ENERGY AND SUBSIDIARIES
THE CONNECTICUT LIGHT AND POWER COMPANY
NSTAR ELECTRIC COMPANY AND SUBSIDIARY
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES


SAFE HARBOR STATEMENT UNDER THE PRIVATE SECURITIES
LITIGATION REFORM ACT OF 1995

References in this Annual Report on Form 10-K to "Eversource," the "Company," "we," "our," and "us" refer to Eversource Energy and its consolidated subsidiaries. CL&P, NSTAR Electric, and PSNH are each doing business as Eversource Energy.  

We make statements concerning our expectations, beliefs, plans, objectives, goals, strategies, assumptions of future events, future financial performance or growth and other statements that are not historical facts. These statements are "forward-looking statements" within the meaning of U.S. federal securities laws. You can generally identify our forward-looking statements through the use of words or phrases such as "estimate," "expect," "anticipate," "intend," "plan," "project," "believe," "forecast," "would," "should," "could," and other similar expressions. Forward-looking statements involve risks and uncertainties that may cause actual results or outcomes to differ materially from those included in our forward-looking statements. Forward-looking statements are based on the current expectations, estimates, assumptions or projections of management and are not guarantees of future performance. These expectations, estimates, assumptions or projections may vary materially from actual results. Accordingly, any such statements are qualified in their entirety by reference to, and are accompanied by, the following important factors that may cause our actual results or outcomes to differ materially from those contained in our forward-looking statements, including, but not limited to:

cyberattacks or breaches, including those resulting in the compromise of the confidentiality of our proprietary information and the personal information of our customers,
our ability to complete the offshore wind investments sales process on the timelines, terms and pricing we expect; if we and the counterparties are unable to satisfy all closing conditions and consummate the purchase and sale transactions with respect to our offshore wind assets; if Sunrise Wind does not win in the OREC contract solicitation process; if we are unable to qualify for investment tax credits related to these projects; if we experience variability in the projected construction costs of the offshore wind projects, if there is a deterioration of market conditions in the offshore wind industry; and if the projects do not commence operation as scheduled or within budget or are not completed,
disruptions in the capital markets or other events that make our access to necessary capital more difficult or costly,
•    changes in economic conditions, including impact on interest rates, tax policies, and customer demand and payment ability,
•    ability or inability to commence and complete our major strategic development projects and opportunities,
•    acts of war or terrorism, physical attacks or grid disturbances that may damage and disrupt our electric transmission and electric, natural gas, and water distribution systems,
•    actions or inaction of local, state and federal regulatory, public policy and taxing bodies,
•    substandard performance of third-party suppliers and service providers,
•    fluctuations in weather patterns, including extreme weather due to climate change,
•    changes in business conditions, which could include disruptive technology or development of alternative energy sources related to our current or future business model,
•    contamination of, or disruption in, our water supplies,
•    changes in levels or timing of capital expenditures,
•    changes in laws, regulations or regulatory policy, including compliance with environmental laws and regulations,
•    changes in accounting standards and financial reporting regulations,
•    actions of rating agencies, and
•    other presently unknown or unforeseen factors.

Other risk factors are detailed in our reports filed with the SEC and are updated as necessary and available on our website at www.eversource.com and on the SEC’s website at www.sec.gov, and we encourage you to consult such disclosures.

All such factors are difficult to predict and contain uncertainties that may materially affect our actual results, many of which are beyond our control.  You should not place undue reliance on the forward-looking statements, as each speaks only as of the date on which such statement is made, and, except as required by federal securities laws, we undertake no obligation to update any forward-looking statement or statements to reflect events or circumstances after the date on which such statement is made or to reflect the occurrence of unanticipated events. New factors emerge from time to time and it is not possible for us to predict all of such factors, nor can we assess the impact of each such factor on the business or the extent to which any factor, or combination of factors, may cause actual results to differ materially from those contained in any forward-looking statements. For more information, see Item 1A, Risk Factors, included in this combined Annual Report on Form 10-K. This Annual Report on Form 10-K also describes material contingencies and critical accounting policies in the accompanying Management's Discussion and Analysis of Financial Condition and Results of Operations and Combined Notes to Financial Statements.  We encourage you to review these items.  

1



EVERSOURCE ENERGY AND SUBSIDIARIES
THE CONNECTICUT LIGHT AND POWER COMPANY
NSTAR ELECTRIC COMPANY AND SUBSIDIARY
PUBLIC SERVICE COMPANY OF NEW HAMPSHIRE AND SUBSIDIARIES

PART I

Item 1.    Business

Please refer to the Glossary of Terms for definitions of defined terms and abbreviations used in this combined Annual Report on Form 10-K.

Eversource Energy (Eversource), headquartered in Boston, Massachusetts and Hartford, Connecticut, is a public utility holding company subject to regulation by the Federal Energy Regulatory Commission (FERC) under the Public Utility Holding Company Act of 2005. We are engaged primarily in the energy delivery business through the following wholly-owned utility subsidiaries:

The Connecticut Light and Power Company (CL&P), a regulated electric utility that serves residential, commercial and industrial customers in parts of Connecticut;

NSTAR Electric Company (NSTAR Electric), a regulated electric utility that serves residential, commercial and industrial customers in parts of eastern and western Massachusetts and owns solar power facilities, and its wholly-owned subsidiary Harbor Electric Energy Company (HEEC), also a regulated electric utility that distributes electric energy to its sole customer;

Public Service Company of New Hampshire (PSNH), a regulated electric utility that serves residential, commercial and industrial customers in parts of New Hampshire;

NSTAR Gas Company (NSTAR Gas), a regulated natural gas utility that serves residential, commercial and industrial customers in parts of Massachusetts;

Eversource Gas Company of Massachusetts (EGMA), a regulated natural gas utility that serves residential, commercial and industrial customers in parts of Massachusetts;

Yankee Gas Services Company (Yankee Gas), a regulated natural gas utility that serves residential, commercial and industrial customers in parts of Connecticut; and

Aquarion Company (Aquarion), a utility holding company that owns five separate regulated water utility subsidiaries and collectively serves residential, commercial, industrial, and municipal and fire protection customers in parts of Connecticut, Massachusetts and New Hampshire.

CL&P, NSTAR Electric and PSNH also serve New England customers through Eversource's electric transmission business. Along with NSTAR Gas, EGMA and Yankee Gas, each is doing business as Eversource Energy in its respective service territory.

Eversource, CL&P, NSTAR Electric and PSNH each report their financial results separately. We also include information in this report on a segment basis for Eversource. Eversource has four reportable segments: electric distribution, electric transmission, natural gas distribution and water distribution. These segments represent substantially all of Eversource's total consolidated revenues. CL&P, NSTAR Electric and PSNH do not report separate business segments.

Eversource has an offshore wind business, which includes 50 percent ownership interests in three offshore wind projects and a tax equity investment in one of the projects. For further information, see "Offshore Wind Business” below.

ELECTRIC DISTRIBUTION SEGMENT

Eversource's electric distribution segment consists of the distribution businesses of CL&P, NSTAR Electric and PSNH, which are engaged in the distribution of electricity to retail customers in Connecticut, Massachusetts and New Hampshire, respectively, and the solar power facilities of NSTAR Electric.

2


ELECTRIC DISTRIBUTION – CONNECTICUT – THE CONNECTICUT LIGHT AND POWER COMPANY

CL&P's distribution business consists primarily of the purchase, delivery and sale of electricity to its residential, commercial and industrial customers. As of December 31, 2023, CL&P furnished retail franchise electric service to approximately 1.28 million customers in 157 cities and towns in Connecticut. CL&P does not own any electric generation facilities.

Rates

CL&P is subject to regulation by the Connecticut Public Utilities Regulatory Authority (PURA), which, among other things, has jurisdiction over rates, certain dispositions of property and plant, mergers and consolidations, issuances of long-term securities, standards of service and construction and operation of facilities.  CL&P's present general rate structure consists of various rate and service classifications covering residential, commercial and industrial services.  CL&P's retail rates include a delivery service component, which includes distribution, transmission, conservation, renewable energy programs and other charges that are assessed on all customers.

Under Connecticut law, all of CL&P's customers are entitled to choose their energy suppliers, while CL&P remains their electric distribution company.  For those customers who do not choose a competitive energy supplier, CL&P purchases power on behalf of, and passes the related cost without mark-up through to, those customers under standard service (SS) rates for customers with less than 500 kilowatts of demand (residential customers and small and medium commercial and industrial customers), and supplier of last resort service (LRS) rates for customers with 500 kilowatts or more of demand (larger commercial and industrial customers). CL&P charges customers only the amount that it pays generators for producing electricity and does not earn a profit on the cost of electricity.

The rates established by PURA for CL&P are comprised of the following:

An electric generation service charge, which recovers energy-related costs incurred as a result of providing electric generation service supply to all customers who have not migrated to competitive energy suppliers.  The generation service charge is adjusted periodically and reconciled annually in accordance with the policies and procedures of the PURA, with any differences refunded to, or recovered from, customers.

A distribution charge, which includes a fixed customer charge and a demand and/or energy charge to collect the costs of building and expanding the infrastructure to deliver electricity to customers, as well as ongoing operating costs to maintain the infrastructure.  

A revenue decoupling adjustment that reconciles annual base distribution rate recovery amounts recovered from customers to the pre-established level of baseline distribution delivery service revenue requirement approved by PURA.

An Electric System Improvements (ESI) charge, which collects the costs of building and expanding the infrastructure to deliver electricity to customers above the level recovered through the distribution charge. The ESI also recovers costs associated with CL&P’s system resiliency program. The ESI is adjusted periodically and reconciled annually in accordance with the policies and procedures of the PURA, with any differences refunded to, or recovered from, customers.

A Federally Mandated Congestion Charge (FMCC), which recovers any costs imposed by the FERC as part of the New England Standard Market Design, including locational marginal pricing, locational installed capacity payments, any costs approved by PURA to reduce these charges, as well as other costs approved by PURA.  The FMCC has both a bypassable component and a non-bypassable component, and is adjusted periodically and reconciled annually in accordance with the policies and procedures of the PURA, with any differences refunded to, or recovered from, customers.

A transmission charge that recovers the cost of transporting electricity over high-voltage lines from generating plants to substations, including costs allocated by ISO-NE to maintain the wholesale electric market. The transmission charge is adjusted periodically and reconciled annually to actual costs incurred, and reviewed by PURA, with any difference refunded to, or recovered from, customers.

A Competitive Transition Assessment (CTA) charge, assessed to recover stranded costs associated with electric industry restructuring such as various IPP contracts.  The CTA is reconciled annually to actual costs incurred and reviewed by PURA, with any difference refunded to, or recovered from, customers.

A Systems Benefits Charge (SBC), established to fund expenses associated with various hardship and low-income programs. The SBC is reconciled annually to actual costs incurred, and reviewed by PURA, with any difference refunded to, or recovered from, customers.  

A Renewable Energy Investment Charge, which is used to promote investment in renewable energy sources.  Amounts collected by this charge are deposited into the Connecticut Clean Energy Fund and administered by the Connecticut Green Bank.  

A Conservation Adjustment Mechanism (CAM) charge established to implement cost-effective energy conservation programs and market transformation initiatives. The CAM charge is reconciled annually to actual costs incurred, and reviewed by PURA, with any difference refunded to, or recovered from, customers through an approved adjustment to the following year’s energy conservation spending plan budget.

3


As required by regulation, CL&P has entered into long-term contracts for the purchase of (i) products from renewable energy facilities, which may include energy, renewable energy certificates, or capacity, (ii) capacity-related contracts with generation facilities, and (iii) contracts for peaking capacity.  Some of these contracts are subject to sharing agreements with UI, whereby CL&P is responsible for 80 percent and UI for 20 percent of the n