Exhibit 4.1

This instrument was prepared

under the supervision of:

John T. Burnett, Deputy General Counsel

Duke Energy Florida, LLC

299 First Avenue North

St. Petersburg, Florida 33701

DUKE ENERGY FLORIDA, LLC

TO

THE BANK OF NEW YORK MELLON, TRUSTEE

FIFTY-THIRD

SUPPLEMENTAL INDENTURE

Dated as of September 1, 2016

This is a security agreement covering personal property as

well as a mortgage upon real estate and other property.

SUPPLEMENT TO INDENTURE

DATED AS OF JANUARY 1, 1944, AS SUPPLEMENTED

TABLE OF CONTENTS*

*      The headings listed in this Table of Contents are for convenience only and should not be included for substantive purposes as part of this Supplemental Indenture.

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RECITALS

SUPPLEMENTAL INDENTURE , dated as of the 1st day of September 2016, made and entered into by and between DUKE ENERGY FLORIDA, LLC , a limited liability company of the State of Florida (hereinafter sometimes called the “Company”), party of the first part, and THE BANK OF NEW YORK MELLON (formerly known of record as The Bank of New York), a New York banking corporation, whose post office address is 101 Barclay Street, New York, New York 10286, as successor trustee (hereinafter sometimes called the “Trustee”), party of the second part.

WHEREAS , the Company has heretofore executed and delivered an indenture of mortgage and deed of trust, titled the Indenture, dated as of January 1, 1944, and the same has been recorded in the public records and on the dates listed on Exhibit A hereto, and for the purpose of preventing the extinguishment of said Indenture under Chapter 712, Florida Statutes, the above-referred-to Indenture applicable to each county in which this instrument is recorded is hereby incorporated herein and made a part hereof by this reference thereto (said Indenture is hereinafter referred to as the “Original Indenture” and with the below-mentioned fifty-two Supplemental Indentures and this Supplemental Indenture and all other indentures, if any, supplemental to the Original Indenture collectively referred to as the “Indenture”), in and by which the Company conveyed and mortgaged to the Trustee certain property therein described to secure the payment of all bonds of the Company to be issued thereunder in one or more series; and

WHEREAS , pursuant to and under the terms of the Original Indenture, the Company issued $16,500,000 First Mortgage Bonds, 3 3/8% Series due 1974; and

WHEREAS , subsequent to the date of the execution and delivery of the Original Indenture, the Company has from time to time executed and delivered fifty-two indentures supplemental to the Original Indenture (together with this Supplemental Indenture, collectively, the “Supplemental Indentures”), providing for the creation of additional series of bonds secured by the Original Indenture and/or for amendment of certain terms and provisions of the Original Indenture and of indentures supplemental thereto, such Supplemental Indentures, and the purposes thereof, being as follows:

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WHEREAS , such Supplemental Indentures have each been recorded in the public records of the counties listed on Exhibit A hereto, on the dates and in the official record books and at the page numbers listed thereon; and

WHEREAS , the Company converted its form of organization effective August 1, 2015 from a Florida corporation to a Florida limited liability company named “Duke Energy Florida, LLC,” and evidence of such conversion was recorded in all counties in the State of Florida in which this Supplemental Indenture is to be recorded; and

WHEREAS , subsequent to the date of the execution and delivery of the Fifty-Second Supplemental Indenture the Company has purchased, constructed or otherwise acquired certain property hereinafter referred to, and the Company desires by this Supplemental Indenture to confirm the lien of the Original Indenture on such property; and

WHEREAS , pursuant to the Forty-Seventh Supplemental Indenture, JPMorgan Chase Bank, N.A., resigned as Trustee and The Bank of New York Mellon was appointed as the successor Trustee, effective December 13, 2007; and

WHEREAS, The Bank of New York Mellon is eligible and qualified to serve as Trustee under the Indenture; and

WHEREAS , the Company desires by this Supplemental Indenture to create a new series of bonds to be designated as First Mortgage Bonds, 3.40% Series due 2046 (the “ 2046 Bonds” or the “New Series Bonds”), to be issued under the Original Indenture pursuant to Section 2.01 of the Original Indenture, and also desires to deliver to the Trustee prior to or simultaneously with the authentication and delivery of the initial issue of Six Hundred Million Dollars

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($600,000,000) principal amount of New Series Bonds pursuant to Section 4.05 of the Original Indenture the documents and instruments required by said section; and

WHEREAS , the Company in the exercise of the powers and authority conferred upon and reserved to it under and by virtue of the Indenture, and pursuant to the resolutions of its Board of Directors (as defined in the Indenture, which definition includes any duly authorized committee of the Board of Directors, including the First Mortgage Bond Indenture Committee of the Board of Directors) has duly resolved and determined to make, execute and deliver to the Trustee a Supplemental Indenture in the form hereof for the purposes herein provided; and

WHEREAS , all conditions and requirements necessary to make this Supplemental Indenture a valid, binding and legal instrument in accordance with its terms have been done, performed and fulfilled, and the execution and delivery hereof have been in all respects duly authorized;

NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE WITNESSETH : That the Company, in consideration of the premises and of One Dollar ($1.00) and other good and valuable consideration to it duly paid by the Trustee at or before the ensealing and delivery of these presents, the receipt whereof is hereby acknowledged, and in order to secure the payment of both the principal of and interest and premium, if any, on the bonds from time to time issued and to be issued under the Indenture, according to their tenor and effect, does hereby confirm the grant, sale, resale, conveyance, assignment, transfer, mortgage and pledge of the property described in the Original Indenture and the Supplemental Indentures (except such properties or interests therein as may have been released or sold or disposed of in whole or in part as permitted by the provisions of the Original Indenture), and hath granted, bargained, sold, released, conveyed, assigned, transferred, mortgaged, pledged, set over and confirmed, and by these presents doth grant, bargain, sell, release, convey, assign, transfer, mortgage, pledge, set over and confirm unto The Bank of New York Mellon, as Trustee, and to its successors in the trust and to its successors and assigns, forever, all property, real, personal and mixed, tangible and intangible, owned by the Company on the date of the execution of this Supplemental Indenture or which may be hereafter acquired by it, including (but not limited to) all property which it has acquired subsequent to the date of execution of the Fifty-Second Supplemental Indenture and situated in the State of Florida, including without limitation the property described on Exhibit  B hereto (in all cases, except such property as is expressly excepted by the Original Indenture from the lien and operation thereof); and without in any way limiting or impairing by the enumeration of the same the scope and intent of the foregoing, all lands, power sites, flowage rights, water rights, water locations, water appropriations, ditches, flumes, reservoirs, reservoir sites, canals, raceways, dams, dam sites, aqueducts and all other rights or means for appropriating, conveying, storing and supplying water; all rights of way and roads; all plants for the generation of electricity by steam, water and/or other power; all power houses, facilities for utilization of natural gas, street lighting systems, if any, standards and other equipment incidental thereto, telephone, radio and television systems, microwave systems, facilities for utilization of water, steam heat and hot water plants, if any, all substations, lines, service and supply systems, bridges, culverts, tracks, offices, buildings and other structures and equipment and fixtures thereof; all machinery, engines, boilers, dynamos, electric machines, regulators, meters, transformers, generators, motors, electrical and mechanical appliances, conduits, cables, pipes, fittings, valves and connections, poles (wood, metal and concrete), and transmission lines, wires, cables, conductors, insulators, tools, implements, apparatus, furniture, chattels, and choses in action; all municipal and other franchises, consents, licenses or permits; all lines for the distribution of electric current, gas, steam heat or water for any purpose including towers, poles (wood, metal and concrete), wires, cables, pipes, conduits, ducts and all apparatus for use in connection therewith; all real estate, lands, easements, servitudes, licenses, permits, franchises, privileges, rights-of-way and other rights in or relating to real estate or the use and occupancy of the same (except as herein or in the Original Indenture or any of the Supplemental Indentures expressly excepted); all the right, title and interest of the Company in and to all other property of any kind or nature appertaining to and/or used and/or occupied and/or enjoyed in connection with any property hereinbefore, or in the Original Indenture and said Supplemental Indentures, described.

IT IS HEREBY AGREED by the Company that all the property, rights and franchises acquired by the Company after the date hereof (except any property herein or in the Original Indenture or any of the Supplemental Indentures expressly excepted) shall, subject to the provisions of Section 9.01 of the Original Indenture and to the extent permitted by law, be as fully embraced within the lien hereof as if such property, rights and franchises were now owned by the Company and/or specifically described herein and conveyed hereby.

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TOGETHER WITH all and singular the tenements, hereditaments and appurtenances belonging or in any way appertaining to the aforesaid mortgaged property or any part thereof, with the reversion and reversions, remainder and remainders and (subject to the provisions of Section 9.01 of the Original Indenture) the tolls, rents, revenues, issues, earnings, income, product and profits thereof, and all the estate, right, title and interest and claim whatsoever, at law as well as in equity, which the Company now has or may hereafter acquire in and to the aforesaid mortgaged property and every part and parcel thereof.

TO HAVE AND TO HOLD THE SAME unto The Bank of New York Mellon, as Trustee, and its successors in the trust and its assigns forever, but IN TRUST NEVERTHELESS upon the terms and trusts set forth in the Indenture, for the benefit and security of those who shall hold the bonds and coupons issued and to be issued under the Indenture, without preference, priority or distinction as to lien of any of said bonds and coupons over any others thereof by reason or priority in the time of the issue or negotiation thereof, or otherwise howsoever, subject, however, to the provisions of Sections 10.03 and 10.12 of the Original Indenture.

SUBJECT, HOWEVER , to the reservations, exceptions, conditions, limitations and restrictions contained in the several deeds, servitudes and contracts or other instruments through which the Company acquired, and/or claims title to and/or enjoys the use of the aforesaid properties; and subject also to encumbrances of the character defined in the Original Indenture as “excepted encumbrances” in so far as the same may attach to any of the property embraced herein.

Without derogating from the security and priority presently afforded by the Indenture and by law for all of the bonds of the Company that have been, are being, and may in the future be, issued pursuant to the Indenture, for purposes of obtaining any additional benefits and security provided by Section 697.04 of the Florida Statutes, the following provisions of this paragraph shall be applicable.  The Indenture also shall secure the payment of both principal and interest and premium, if any, on the bonds from time to time hereafter issued pursuant to the Indenture, according to their tenor and effect, and the performance and observance of all the provisions of the Indenture (including any indentures supplemental thereto and any modification or alteration thereof made as therein provided), whether the issuance of such bonds may be optional or mandatory, and for any purpose, within twenty (20) years from the date of this Supplemental Indenture.  The total amount of indebtedness secured by the Indenture may decrease or increase from time to time, but the total unpaid balance so secured at any one time shall not exceed the maximum principal amount of $10,000,000,000, plus interest and premium, if any, as well as any disbursements made for the payment of taxes, levies or insurance on the property encumbered by the Indenture, with interest on those disbursements, plus any increase in the principal balance as the result of negative amortization or deferred interest.  For purposes of Section 697.04 of the Florida Statutes, the Original Indenture, as well as all of the indentures supplemental thereto that have been executed prior to the date of this Supplemental Indenture, are incorporated herein by this reference with the same effect as if they had been set forth in full herein.

And, upon the consideration hereinbefore set forth, the Company does hereby covenant and agree to and with the Trustee and its successors in trust under the Indenture for the benefit of those who shall hold bonds and coupons issued and to be issued under the Indenture, as follows:

ARTICLE I

THE NEW SERIES BONDS

A.  CREATION OF FIRST MORTGAGE BONDS, 3.40% SERIES DUE 2046

Section 1.  The Company hereby creates a new series of bonds, not limited in principal amount except as provided in the Original Indenture, to be issued under and secured by the Original Indenture, to be designated by the title “First Mortgage Bonds, 3.40% Series due 2046.” The initial issue of the 2046 Bonds shall consist of Six Hundred Million Dollars ($600,000,000) principal amount thereof.  Subject to the terms of the Indenture, the principal amount of the 2046 Bonds is unlimited.  The Company may, at its option in the future, issue additional 2046 Bonds.

The 2046 Bonds shall be issued only as registered bonds without coupons in the denomination of Two Thousand Dollars ($2,000) and any integral multiple of One Thousand Dollars ($1,000) above that amount.

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Section 2.  (a) The 2046 Bonds shall be issued in registered form without coupons and shall be issued initially in the form of one or more Global Bonds (each such Global Bond, a “2046 Global Bond”) to or on behalf of The Depository Trust Company (“DTC”), as depositary therefor (in such capacity, the “Depositary”), and registered in the name of such Depositary or its nominee.  Any 2046 Bonds to be issued or transferred to, or to be held by or on behalf of DTC as such Depositary or such nominee (or any successor of such nominee) for such purpose shall bear the depositary legends in substantially the form set forth at the top of the form of the 2046 Bonds in Section B of this Article I, unless otherwise agreed by the Company, and in the case of a successor Depositary, such legend or legends as such Depositary and/or the Company shall require and to which each shall agree, in each case such agreement to be confirmed in writing to the Trustee.  Principal of, and interest on, the 2046 Bonds and the Redemption Price (as defined below), if applicable, will be payable, the transfer of the 2046 Bonds will be registrable and the 2046 Bonds will be exchangeable for the 2046 Bonds bearing identical terms and provisions, at the office or agency of the Company in the Borough of Manhattan, The City and State of New York; provided, however, that payment of interest may be made at the option of the Company by check mailed to the registered holders thereof at their registered address; and further provided, however, that with respect to a 2046 Global Bond, the Company may make payments of principal of, and interest on, the 2046 Global Bond and the Redemption Price, if applicable, and interest on such 2046 Global Bond pursuant to and in accordance with such arrangements as are agreed upon by the Company and the Depositary for such 2046 Global Bond.  The 2046 Bonds shall have the terms set forth in the form of the New Series Bond set forth in Section B of this Article I.

(b)                                  Notwithstanding any other provision of this Subsection A.2 of this Article I or of Section 2.03 of the Original Indenture, except as contemplated by the provisions of paragraph (c) below, a 2046 Global Bond may be transferred, in whole but not in part and in the manner provided in Section 2.03 of the Original Indenture, only to a nominee of the Depositary for such 2046 Global Bond, or to the Depositary, or to a successor Depositary for such 2046 Global Bond selected or approved by the Company, or to a nominee of such successor Depositary.

(c)                                   (1) If at any time the Depositary for a 2046 Global Bond notifies the Company that it is unwilling or unable to continue as the Depositary for such 2046 Global Bond or if at any time the Depositary for a 2046 Global Bond ceases to be a clearing agency registered under the Securities Exchange Act of 1934, as amended, at a time when the Depositary is required to be so registered to act as such Depositary, the Company shall appoint a successor Depositary with respect to such 2046 Global Bond.  If a successor Depositary for such 2046 Global Bond is not appointed by the Company within 90 days after the Company receives such notice or becomes aware of such cessation, the Company will execute, and the Trustee, upon receipt of a Company order for the authentication and delivery of 2046 Bonds in the form of definitive certificates in exchange for such 2046 Global Bond, will authenticate and deliver, without service charge, 2046 Bonds in the form of definitive certificates of like tenor and terms in an aggregate principal amount equal to the principal amount of the 2046 Global Bond in exchange for such 2046 Global Bond.  Such 2046 Bonds will be issued to and registered in the name of such person or persons as are specified by the Depositary.

(2)                                  The Company may at any time and in its sole discretion (subject to the procedures of the Depositary) determine that any 2046 Bonds issued or issuable in the form of one or more 2046 Global Bonds shall no longer be represented by such 2046 Global Bond or Bonds.  In any such event the Company will execute, and the Trustee, upon receipt of a Company order for the authentication and delivery of 2046 Bonds in the form of definitive certificates in exchange in whole or in part for such 2046 Global Bond or Bonds, will authenticate and deliver, without service charge, to each person specified by the Depositary, 2046 Bonds in the form of definitive certificates of like tenor and terms in an aggregate principal amount equal to the principal amount of such 2046 Global Bond or the aggregate principal amount of such 2046 Global Bonds in exchange for such 2046 Global Bond or Bonds.

(3)                                  If at any time a completed default has occurred and is continuing with respect to the 2046 Bonds and beneficial owners of a majority in aggregate principal amount of the 2046 Bonds represented by 2046 Global Bonds advise the Depositary to cease acting as the Depositary, the Company will execute, and the Trustee, upon receipt of a Company order for the authentication and delivery of 2046 Bonds in the form of definitive certificates in exchange for such 2046 Global Bond, will authenticate and deliver, without service charge, 2046 Bonds in the form of definitive certificates of like tenor and terms in an aggregate principal amount equal to the principal amount of the 2046 Global Bond in exchange for such 2046 Global Bond.  Such 2046 Bonds will be issued to and registered in the name of such person or persons as are specified by the Depositary.

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(4)           In any exchange provided for in any of the preceding three subparagraphs, the Company shall execute and the Trustee shall authenticate and deliver 2046 Bonds in the form of definitive certificates in authorized denominations.  Upon the exchange of the entire principal amount of a 2046 Global Bond for 2046 Bonds in the form of definitive certificates, such 2046 Global Bond shall be canceled by the Trustee.  Except as provided in the immediately preceding subparagraph, 2046 Bonds issued in exchange for a 2046 Global Bond pursuant to Subsection A.2 of this Article I shall be registered in such names and in such authorized denominations as the Depositary for such 2046 Global Bond, acting pursuant to instructions from its direct or indirect participants or otherwise, shall instruct the Trustee.  Provided that the Company and the Trustee have so agreed, the Trustee shall deliver such 2046 Bonds to the persons in whose names the 2046 Bonds are so to be registered.

(5)           Any endorsement of a 2046 Global Bond to reflect the principal amount thereof, or any increase or decrease in such principal amount, shall be made in such manner and by such person or persons as shall be specified in or pursuant to any applicable letter of representations or other arrangement entered into with, or procedures of, the Depositary with respect to such 2046 Global Bond or in the Company order delivered or to be delivered pursuant to Section 4.07 of the Original Indenture with respect thereto.  Subject to the provisions of Section 4.07 of the Original Indenture, the Trustee shall deliver and redeliver any such 2046 Global Bond in the manner and upon instructions given by the person or persons specified in or pursuant to any applicable letter of representations or other arrangement entered into with, or procedures of, the Depositary with respect to such 2046 Global Bond or in any applicable Company order.  If a Company order pursuant to Section 4.07 of the Original Indenture is so delivered, any instructions by the Company with respect to such 2046 Global Bond contained therein shall be in writing but need not be accompanied by or contained in an officers’ certificate and need not be accompanied by an opinion of counsel.

(6)           The Depositary or, if there be one, its nominee, shall be the holder of a 2046 Global Bond for all purposes under the Indenture and the 2046 Bonds and beneficial owners with respect to such 2046 Global Bond shall hold their interests pursuant to applicable procedures of such Depositary.  The Company, the Trustee and any bond registrar shall be entitled to deal with such Depositary for all purposes of the Indenture relating to such 2046 Global Bond (including the payment of principal, the Redemption Price, if applicable, and interest and the giving of instructions or directions by or to the beneficial owners of such 2046 Global Bond as the sole holder of such 2046 Global Bond and shall have no obligations to the beneficial owners thereof (including any direct or indirect participants in such Depositary)).  None of the Company, the Trustee, any paying agent or bond registrar shall have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests of a beneficial owner in or pursuant to any applicable letter of representations or other arrangement entered into with, or procedures of, the Depositary with respect to such 2046 Global Bond or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

Section 3.  September 9, 2016, shall be the date of the beginning of the first interest period for the 2046 Bonds.  The first Interest Payment Date (as defined below) shall be April 1, 2017.  The 2046 Bonds shall be dated as provided in Section 2.01 of the Original Indenture.  The 2046 Bonds shall be payable on October 1, 2046, in such coin or currency of the United States of America as at the time of payment is legal tender for the payment of public and private debts, and shall bear interest, payable in like coin or currency, at the rate of 3.40% per annum, payable semiannually on April 1 and October 1 of each year (each an “Interest Payment Date”) to the persons in whose names the 2046 Bonds are registered at the close of business on the tenth calendar day next preceding the Interest Payment Date (i.e., March 22 and September 21, respectively) (each a “Regular Record Date”), provided, however, that so long as the 2046 Bonds are registered in the name of DTC, its nominee or a successor depository, the Regular Record Date for interest payable on any Interest Payment Date shall be the close of business on the business day immediately preceding such Interest Payment Date (each subject to certain exceptions provided in this Supplemental Indenture and the Indenture), until maturity, according to the terms of the bonds or on prior redemption or by declaration or otherwise, and at the highest rate of interest borne by any of the bonds outstanding under the Indenture from such date of maturity until they shall be paid or payment thereof shall have been duly provided for.  Principal of, and interest on, the 2046 Bonds and the Redemption Price, if applicable, shall be payable at the office or agency of the Company in the Borough of Manhattan, The City of New York; provided, however , that payment of interest may be made, at the option of the Company, by check mailed by the Company or its affiliate to the person entitled thereto at his registered address.  If a due date for the payment of interest, principal or the Redemption Price, if applicable, falls on a day that is not a business day, then the payment will be made on the next succeeding business day, and no interest will accrue on the amounts payable for the period from and after the original due date

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and until the next business day.  The term “business day” means any day other than a Saturday or Sunday or day on which banking institutions in The City of New York are required or authorized to close.

At any time before April 1, 2046 (the “Par Call Date”), the 2046 Bonds shall be redeemable, in whole or in part and from time to time, at the option of the Company, on any date (a “Redemption Date”), at a redemption price (the “Make-Whole Redemption Price”) equal to the greater of (i) 100% of the principal amount of the 2046 Bonds being redeemed and (ii) the sum of the present values of the remaining scheduled payments of principal and interest on the 2046 Bonds being redeemed that would be due if the 2046 Bonds matured on the Par Call Date (exclusive of interest accrued to such Redemption Date) discounted to such Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus 20 basis points, plus, in either case, accrued and unpaid interest on the principal amount being redeemed to, but excluding, such Redemption Date.

At any time on or after the Par Call Date, the 2046 Bonds shall be redeemable, in whole or in part and from time to time, at the option of the Company, at a redemption price (together with any Make-Whole Redemption Price, each a “Redemption Price”) equal to 100% of the principal amount of the 2046 Bonds being redeemed plus accrued and unpaid interest on the principal amount being redeemed to, but excluding, such Redemption Date.

For purposes of the second preceding paragraph of this Section 3, the following terms have the following meanings:

“Comparable Treasury Issue” means the United States Treasury security selected by the Quotation Agent as having an actual or interpolated maturity comparable to the remaining term of the 2046 Bonds to be redeemed (assuming, for this purpose, that the 2046 Bonds matured on the Par Call Date), that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the 2046 Bonds.

“Comparable Treasury Price” means, with respect to any Redemption Date, (1) the average of the Reference Treasury Dealer Quotations for such Redemption Date, after excluding the highest and lowest of such Reference Treasury Dealer Quotations, or (2) if the Quotation Agent obtains fewer than four of such Reference Treasury Dealer Quotations, the average of all such Reference Treasury Dealer Quotations as determined by the Company.

“Quotation Agent” means a Reference Treasury Dealer appointed by the Company.

“Reference Treasury Dealer” means each of J.P. Morgan Securities LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated, The Bank of Nova Scotia, New York Agency (an affiliate of Scotia Capital (USA) Inc.), and a Primary Treasury Dealer (as defined below) selected by SunTrust Robinson Humphrey, Inc., plus one other financial institution appointed by the Company at the time of any redemption, or their respective affiliates or successors, each of which is a primary U.S. Government securities dealer in the United States (a “Primary Treasury Dealer”); provided, however , that if any of the foregoing or their affiliates or successors shall cease to be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any Redemption Date, the average, as determined by the Quotation Agent, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Quotation Agent by such Reference Treasury Dealer at 5:00 p.m., New York City time, on the third business day preceding such Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date, the rate per annum equal to the semi-annual equivalent yield to maturity or interpolated maturity (on a day count basis) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal amount) equal to the Comparable Treasury Price for such Redemption Date.  The Treasury Rate shall be calculated by the Company on the third business day preceding the Redemption Date.

So long as the 2046 Bonds are registered in the name of DTC, its nominee or a successor depositary, if the Company elects to redeem less than all of the 2046 Bonds, DTC’s practice is to determine by lot the amount of the interest of

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each Direct Participant in the 2046 Bonds to be redeemed.  At all other times, the Trustee shall draw by lot, in such manner as it deems appropriate, the particular 2046 Bonds, or portions of them, to be redeemed.

The 2046 Bonds shall also be redeemable, as a whole but not in part, at the Make-Whole Redemption Price in the event that (i) all the outstanding common stock of the Company shall be acquired by some governmental body or instrumentality and the Company elects to redeem all of the bonds of all series, the Redemption Date in any such event to be not more than one hundred twenty (120) days after the date on which all said stock is so acquired, or (ii) all, or substantially all, the mortgaged and pledged property constituting bondable property which at the time shall be subject to the lien of the Indenture as a first lien shall be released from the lien of the Indenture pursuant to the provisions thereof, and available moneys in the hands of the Trustee, including any moneys deposited by the Company available for the purpose, are sufficient to redeem all the bonds of all series at the redemption prices (together with accrued interest to the date of redemption) specified therein applicable to the redemption thereof upon the happening of such event.

Notice of redemption shall be given by mail not less than 30 nor more than 90 days prior to the date fixed for redemption to the holders of 2046 Bonds to be redeemed (which, as long as the 2046 Bonds are held in the book-entry only system, will be the Depositary, its nominee or a successor depositary).  On and after the date fixed for redemption (unless the Company defaults in the payment of the Redemption Price and interest accrued thereon to such date), interest on the 2046 Bonds or the portions of them so called for redemption shall cease to accrue.  If the Company elects to redeem any 2046 Bonds, the Company will notify the Trustee of its election at least 45 days prior to the Redemption Date (or a shorter period acceptable to the Trustee).  The Company will provide the Trustee a reasonably detailed computation of the Redemption Price with such notice (or if the Redemption Price includes the Make Whole Redemption Price, the manner of calculation, with the actual computation provided by the Company to the Trustee promptly following its computation).

The 2046 Bonds of the several denominations are exchangeable for a like aggregate principal amount of other 2046 Bonds of other authorized denominations.  Notwithstanding the provisions of Section 2.03 of the Original Indenture, for any exchange of the 2046 Bonds for other 2046 Bonds of different authorized denominations, or for any transfer of 2046 Bonds, the Company may require the payment of a sum sufficient to reimburse it for any tax or other governmental charge incident thereto only.  The 2046 Bonds may be presented for transfer or exchange at the corporate trust office of the Trustee in New York, New York.

B.  FORM OF THE NEW SERIES BONDS

The New Series Bonds shall be substantially in the following form, with such inclusions, omissions, and variations as the Board of Directors of the Company may determine in accordance with the provisions of the Indenture and with such variations, as set forth therein:

[FORM OF THE NEW SERIES BONDS]

[Insert applicable depositary legend or legends, which initially shall be the following:

THIS SECURITY IS A GLOBAL NOTE WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF A DEPOSITARY OR A NOMINEE THEREOF.  THIS SECURITY MAY NOT BE EXCHANGED IN WHOLE OR IN PART FOR A SECURITY REGISTERED, AND NO TRANSFER OF THIS SECURITY IN WHOLE OR IN PART MAY BE REGISTERED, IN THE NAME OF ANY PERSON OTHER THAN SUCH DEPOSITARY OR A NOMINEE THEREOF, EXCEPT IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE INDENTURE.

UNLESS THIS CERTIFICATE IS PRESENTED BY AN AUTHORIZED REPRESENTATIVE OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), TO DUKE ENERGY FLORIDA, LLC OR ITS AGENT FOR REGISTRATION OF TRANSFER, EXCHANGE, OR PAYMENT, AND ANY CERTIFICATE ISSUED IS REGISTERED IN THE NAME OF CEDE & CO. OR IN SUCH OTHER NAME AS IS REQUESTED BY AN AUTHORIZED REPRESENTATIVE OF DTC (AND ANY PAYMENT IS MADE TO CEDE & CO. OR TO SUCH OTHER ENTITY AS IS REQUESTED BY AN AUTHORIZED

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REPRESENTATIVE OF DTC), ANY TRANSFER, PLEDGE, OR OTHER USE HEREOF FOR VALUE OR OTHERWISE BY OR TO ANY PERSON IS WRONGFUL INASMUCH AS THE REGISTERED OWNER HEREOF, CEDE & CO., HAS AN INTEREST HEREIN.

THIS FIRST MORTGAGE BOND,       % SERIES DUE 20       MAY, UNDER CONDITIONS PROVIDED IN THE INDENTURE, BE EXCHANGED FOR FIRST MORTGAGE BONDS,     % SERIES DUE 20       IN THE FORM OF DEFINITIVE CERTIFICATES OF LIKE TENOR AND OF AN EQUAL AGGREGATE PRINCIPAL AMOUNT, IN AUTHORIZED DENOMINATIONS, REGISTERED IN THE NAMES OF SUCH PERSONS AS THE DEPOSITARY SHALL INSTRUCT THE TRUSTEE.  ANY SUCH EXCHANGE SHALL BE MADE UPON RECEIPT BY THE TRUSTEE OF AN OFFICERS’ CERTIFICATE THEREFOR AND A WRITTEN INSTRUCTION FROM THE DEPOSITARY SETTING FORTH THE NAME OR NAMES IN WHICH THE TRUSTEE IS TO REGISTER SUCH FIRST MORTGAGE BONDS,       % SERIES DUE 20       IN THE FORM OF DEFINITIVE CERTIFICATES.]

DUKE ENERGY FLORIDA, LLC

(Organized under the laws of the State of Florida)

FIRST MORTGAGE BOND,
% SERIES DUE 20

DUE               , 20

DUKE ENERGY FLORIDA, LLC, a limited liability company of the State of Florida (hereinafter called the Company), for value received, hereby promises to pay to                    or registered assigns, on                    at the office or agency of the Company in the Borough of Manhattan, The City of New York,                    Dollars ($                  ) in such coin or currency of the United States of America as at the time of payment is legal tender for the payment of public and private debts, and to pay interest thereon, semiannually on April 1 and October 1 of each year, commencing April 1, 2017, to the person in whose name this bond is registered at the close of business on the tenth calendar day next preceding the interest payment date (i.e., March 22 and September 21, respectively), provided, however , that so long as this bond is registered in the name of The Depository Trust Company, its nominee or a successor depository, the record date for interest payable on any interest payment date shall be the close of business on the business day immediately preceding such interest payment date (each subject to certain exceptions provided in the Mortgage hereinafter mentioned), at the rate of                    per annum, at said office or agency in like coin or currency, from the date hereof until this bond shall mature, according to its terms or on prior redemption or by declaration or otherwise, and at the highest rate of interest borne by any of the bonds outstanding under the Mortgage hereinafter mentioned from such date of maturity until this bond shall be paid or the payment hereof shall have been duly provided for; provided, however , that payment of interest may be made at the option of the Company by check mailed by the Company or its affiliate to the person entitled thereto at his registered address.  If a due date for the payment of interest, principal, or the Redemption Price, if applicable, falls on a day that is not a business day, then the payment will be made on the next succeeding business day, and no interest will accrue on the amounts payable for the period from and after the original due date and until the next business day.  The term “business day” means any day other than a Saturday or Sunday or day on which banking institutions in The City of New York are required or authorized to close.

Additional provisions of this bond are set forth on the reverse hereof and such provisions shall for all purposes have the same effect as though fully set forth at this place.

This bond shall not become valid or obligatory for any purpose until The Bank of New York Mellon, or its successor as Trustee under the Mortgage, shall have signed the certificate of authentication endorsed hereon.

IN WITNESS WHEREOF, DUKE ENERGY FLORIDA, LLC has caused this bond to be signed in its name by its President or one of its Vice Presidents by his signature or a facsimile thereof, and its company seal, or a facsimile

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thereof, to be affixed hereto and attested by its Secretary or one of its Assistant Secretaries by his signature or a facsimile thereof.

Dated: September    , 2016

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TRUSTEE’S AUTHENTICATION CERTIFICATE

This bond is one of the bonds, of the series herein designated, described or provided for in the within-mentioned Mortgage.

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[TEXT APPEARING ON REVERSE SIDE OF BOND]

DUKE ENERGY FLORIDA, LLC

FIRST MORTGAGE BOND
% SERIES DUE 20

DUE                    , 20

This bond is one of an issue of bonds of the Company (herein referred to as the bonds), not limited in principal amount except as provided in the Mortgage hereinafter mentioned, issuable in series, which different series may mature at different times, may bear interest at different rates, and may otherwise vary as provided in the Mortgage hereinafter mentioned, and is one of a series known as its First Mortgage Bonds,     % Series due 20     (herein referred to as the “Bonds of this Series”), all bonds of all series issued and to be issued under and equally and ratably secured (except insofar as any sinking or analogous fund, established in accordance with the provisions of the Mortgage hereinafter mentioned, may afford additional security for the bonds of any particular series) by an Indenture dated as of January 1, 1944 (the “Original Indenture” and herein, together with all indentures supplemental thereto including the Fifty-Third Supplemental Indenture dated as of September 1, 2016 (the “Fifty-Third Supplemental Indenture”) between the Company and The Bank of New York Mellon, as Trustee, called the “Mortgage”), to which reference is made for the nature and extent of the security, the rights of the holders of bonds and of the Company in respect thereof, the rights, duties and immunities of the Trustee, and the terms and conditions upon which the bonds are, and are to be, issued and secured.  The Mortgage contains provisions permitting the holders of not less than seventy-five per centum (75%) in principal amount of all the bonds at the time outstanding, determined and evidenced as provided in the Mortgage, or in case the rights under the Mortgage of the holders of bonds of one or more, but less than all, of the series of bonds outstanding shall be affected, the holders of not less than seventy-five per centum (75%) in principal amount of the bonds at the time outstanding of all series affected, determined and evidenced as provided in the Mortgage, on behalf of the holders of all the bonds to waive any past default under the Mortgage and its consequences except a completed default, as defined in the Mortgage, in respect of the payment of the principal of or interest on any bond or default arising from the creation of any lien ranking prior to or equal with the lien of the Mortgage on any of the mortgaged and pledged property.  The Mortgage also contains provisions permitting the Company and the Trustee, with the consent of the holders of not less than seventy-five per centum (75%) in principal amount of all the bonds at the time outstanding, determined and evidenced as provided in the Mortgage, or in case the rights under the Mortgage of the holders of bonds of one or more, but less than all, of the series of bonds outstanding shall be affected, then with the consent of the holders of not less than seventy-five per centum (75%) in principal amount of the bonds at the time outstanding of all series affected, determined and evidenced as provided in the Mortgage, to execute supplemental indentures adding any provisions to or changing in any manner or eliminating any of the provisions of the Mortgage or modifying in any manner the rights of the holders of the bonds and coupons; provided, however, that no such supplemental indenture shall (i) extend the fixed maturity of any bonds, or reduce the rate or extend the time of payment of interest thereon, or reduce the principal amount thereof, without the express consent of the holder of each bond so affected, or (ii) reduce the aforesaid percentage of bonds, the holders of which are required to consent to any such supplemental indenture, without the consent of the holders of all bonds then outstanding, or (iii) permit the creation of any lien ranking prior to or equal with the lien of the Mortgage on any of the mortgaged and pledged property, or (iv) deprive the holder of any outstanding bond of the lien of the Mortgage on any of the mortgaged and pledged property.  Any such waiver or consent by the registered holder of this bond (unless effectively revoked as provided in the Mortgage) shall be conclusive and binding upon such holder and upon all future holders of this bond, irrespective of whether or not any notation of such waiver or consent is made upon this bond.  No reference herein to the Mortgage and no provision of this bond or of the Mortgage shall alter or impair the obligation of the Company, which is absolute and unconditional, to pay the principal of and interest on this bond at the time and place and at the rate and in the coin or currency herein prescribed.

The Bonds of this Series are issuable in denominations of Two Thousand Dollars ($2,000) and any integral multiple of One Thousand Dollars ($1,000) above that amount and are exchangeable for a like aggregate principal amount of Bonds of this Series of other authorized denominations.  This bond is transferable as prescribed in the Mortgage by the registered holder hereof in person, or by his duly authorized attorney, at the office or agency of the Company in said Borough of Manhattan, The City of New York, upon surrender and cancellation of this bond, and upon payment, if the Company shall require it, of the transfer charges prescribed in the Fifty-Third Supplemental

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Indenture hereinabove referred to, and thereupon a new fully registered bond or bonds of authorized denominations of the same series and for the same aggregate principal amount will be issued to the transferee in exchange herefor as provided in the Mortgage.  The Company and the Trustee, any paying agent and any bond registrar may deem and treat the person in whose name this bond is registered as the absolute owner hereof, whether or not this bond shall be overdue, for the purpose of receiving payment and for all other purposes and neither the Company nor the Trustee nor any paying agent nor any bond registrar shall be affected by any notice to the contrary.

At any time before April 1, 2046 (the “Par Call Date”), the Bonds of this Series shall be redeemable, in whole or in part and from time to time, at the option of the Company, on any date (a “Redemption Date”), at a redemption price (the “Make-Whole Redemption Price”) equal to the greater of (i) 100% of the principal amount of the Bonds of this Series being redeemed and (ii) the sum of the present values of the remaining scheduled payments of principal and interest on the Bonds of this series being redeemed that would be due if the Bonds of this series matured on the Par Call Date (exclusive of interest accrued to such Redemption Date) discounted to such Redemption Date on a semi-annual basis (assuming a 360-day year consisting of twelve 30-day months) at the Treasury Rate plus 20 basis points, plus, in either case, accrued and unpaid interest on the principal amount being redeemed to, but excluding, such Redemption Date.

At any time on or after the Par Call Date, the Bonds of this Series shall be redeemable, in whole or in part and from time to time, at the option of the Company, at a redemption price (together with any Make-Whole Redemption Price, each a “Redemption Price”) equal to 100% of the principal amount of the Bonds of this Series being redeemed plus accrued and unpaid interest on the principal amount being redeemed to, but excluding, such Redemption Date.

For purposes of the second immediately preceding paragraph, the following terms have the following meanings:

“Comparable Treasury Issue” means the United States Treasury security selected by the Quotation Agent as having an actual or interpolated maturity comparable to the remaining term of the Bonds of this Series to be redeemed (assuming, for this purpose, that the Bond of this series matured on the Par Call Date) that would be utilized, at the time of selection and in accordance with customary financial practice, in pricing new issues of corporate debt securities of comparable maturity to the remaining term of the Bonds of this Series.

“Comparable Treasury Price” means, with respect to any Redemption Date for the Bonds of this Series, (1) the average of the Reference Treasury Dealer Quotations for such Redemption Date, after excluding the highest and lowest of such Reference Treasury Dealer Quotations, or (2) if the Quotation Agent obtains fewer than four of such Reference Treasury Dealer Quotations, the average of all such Reference Treasury Dealer Quotations as determined by the Company.

“Quotation Agent” means a Reference Treasury Dealer appointed by the Company.

“Reference Treasury Dealer” means each of J.P. Morgan Securities LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated, The Bank of Nova Scotia, New York Agency (an affiliate of Scotia Capital (USA) Inc.), and a Primary Treasury Dealer (as defined below) selected by SunTrust Robinson Humphrey, Inc., plus one other financial institution appointed by the Company at the time of any redemption of the Bonds of this Series], or their respective affiliates or successors, each of which is a primary U.S. Government securities dealer in the United States (a “Primary Treasury Dealer”); provided, however , that if any of the foregoing or their affiliates or successors shall cease to be a Primary Treasury Dealer, the Company shall substitute therefor another Primary Treasury Dealer.

“Reference Treasury Dealer Quotations” means, with respect to each Reference Treasury Dealer and any Redemption Date for the Bonds of this Series, the average, as determined by the Quotation Agent, of the bid and asked prices for the Comparable Treasury Issue (expressed in each case as a percentage of its principal amount) quoted in writing to the Quotation Agent by such Reference Treasury Dealer at 5:00 p.m., New York City time, on the third business day preceding such Redemption Date.

“Treasury Rate” means, with respect to any Redemption Date for the Bonds of this Series, the rate per annum equal to the semi-annual equivalent yield to maturity or interpolated maturity (on a day count basis) of the Comparable Treasury Issue, assuming a price for the Comparable Treasury Issue (expressed as a percentage of its principal

14

amount) equal to the Comparable Treasury Price for such Redemption Date.  The Treasury Rate shall be calculated  by the Company on the third business day preceding the Redemption Date.

So long as the Bonds of this Series are registered in the name of DTC, its nominee or a successor depositary, if the Company elects to redeem less than all of the Bonds of this Series, DTC’s practice is to determine by lot the amount of the interest of each Direct Participant in the Bonds of this Series to be redeemed.  At all other times, the Trustee shall draw by lot, in such manner as it deems appropriate, the particular Bonds of this Series, or portions of them, to be redeemed.

The Bonds of this Series shall also be redeemable, as a whole but not in part, at the Make-Whole Redemption Price in the event that (i) all the outstanding common stock of the Company shall be acquired by some governmental body or instrumentality and the Company elects to redeem all of the bonds of all series, the Redemption Date in any such event to be not more than one hundred twenty (120) days after the date on which all said stock is so acquired, or (ii) all, or substantially all, the mortgaged and pledged property constituting bondable property which at the time shall be subject to the lien of the Mortgage as a first lien shall be released from the lien of the Mortgage pursuant to the provisions thereof, and available moneys in the hands of the Trustee, including any moneys deposited by the Company available for the purpose, are sufficient to redeem all the bonds of all series at the redemption prices (together with accrued interest to the date of redemption) specified therein applicable to the redemption thereof upon the happening of such event.

Notice of redemption shall be given by mail not less than 30 nor more than 90 days prior to the date fixed for redemption to the holders of the Bonds of this Series to be redeemed (which, as long as the Bonds of this Series are held in the book-entry only system, will be the Depositary, its nominee or a successor depositary).  On and after the date fixed for redemption (unless the Company defaults in the payment of the Redemption Price and interest accrued thereon to such date), interest on the Bonds of this Series or the portions of them so called for redemption shall cease to accrue.  If the Company elects to redeem any Bonds of this Series, the Company will notify the Trustee of its election at least 45 days prior to the Redemption Date (or a shorter period acceptable to the Trustee).  The Company will provide the Trustee a reasonably detailed computation of the Redemption Price with such notice (or if the Redemption Price includes the Make Whole Redemption Price, the manner of calculation, with the actual computation provided by the Company to the Trustee promptly following its computation).

The Mortgage provides that if the Company shall deposit with The Bank of New York Mellon or its successor as Trustee in trust for the purpose funds sufficient to pay the principal of all the bonds of any series, or such of the bonds of any series as have been or are to be called for redemption (including any portions, constituting $1,000 or an integral multiple thereof, of fully registered bonds), and premium, if any, thereon, and all interest payable on such bonds (or portions) to the date on which they become due and payable at maturity or upon redemption or otherwise, and complies with the other provisions of the Mortgage in respect thereof, then from the date of such deposit such bonds (or portions) shall no longer be secured by the lien of the Mortgage.

The Mortgage provides that, upon any partial redemption of a fully registered bond, upon surrender thereof endorsed for transfer, new bonds of the same series and of authorized denominations in principal amount equal to the unredeemed portion of such fully registered bond will be delivered in exchange therefor.

The principal hereof may be declared or may become due prior to the express date of the maturity hereof on the conditions, in the manner and at the time set forth in the Mortgage, upon the occurrence of a completed default as in the Mortgage provided.

No recourse shall be had for the payment of the principal of, the Redemption Price, if applicable, or interest on this bond, or for any claim based hereon, or otherwise in respect hereof, or based on or in respect of the Mortgage or under or upon any obligation, covenant or agreement contained in the Mortgage, against any incorporator or any past, present or future subscriber to the capital stock, stockholder, officer or director, as such, of the Company or of any predecessor or successor corporation, either directly or through the Company or any predecessor or successor corporation under any present or future rule of law, statute or constitution or by the enforcement of any assessment or otherwise, all such liability of incorporators, subscribers, stockholders, officers and directors, as such, being waived and released by the holder and owner hereof by the acceptance of this bond and being likewise waived and released by the terms of the Mortgage.

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C.  INTEREST ON THE NEW SERIES BONDS

Interest on any New Series Bond which is payable, and is punctually paid or duly provided for, on any Interest Payment Date shall be paid to the person in whose name that bond (or one or more predecessor bonds) is registered at the close of business on the Regular Record Date for such interest specified in the provisions of this Supplemental Indenture .  Interest shall be computed on the basis of a 360-day year composed of twelve 30-day months.

Any interest on any New Series Bond which is payable, but is not punctually paid or duly provided for, on any Interest Payment Date (herein called “Defaulted Interest”) shall forthwith cease to be payable to the registered holder on the relevant Regular Record Date solely by virtue of such holder having been such holder; and such Defaulted Interest may be paid by the Company, at its election in each case, as provided in Subsection A or B below:

A.            The Company may elect to make payment of any Defaulted Interest on the New Series Bonds to the persons in whose names such bonds (or their respective predecessor bonds) are registered at the close of business on a special record date for the payment of such Defaulted Interest, which shall be fixed in the following manner (a “Special Record Date”).  The Company shall notify the Trustee in writing of the amount of Defaulted Interest proposed to be paid on each bond and the date of the proposed payment (which date shall be such as will enable the Trustee to comply with the next sentence hereof), and at the same time the Company shall deposit with the Trustee an amount of money equal to the aggregate amount proposed to be paid in respect of such Defaulted Interest or shall make arrangements satisfactory to the Trustee for such deposit prior to the date of the proposed payment, such money when deposited to be held in trust for the benefit of the persons entitled to such Defaulted Interest as in this Subsection provided and not to be deemed part of the trust estate or trust moneys .  Thereupon the Trustee shall fix a Special Record Date for the payment of such Defaulted Interest which shall be not more than 15 nor less than 10 days prior to the date of the proposed payment and not less than 10 days after the receipt by the Trustee of the notice of the proposed payment .  The Trustee shall promptly notify the Company of such Special Record Date and, in the name and at the expense of the Company, shall cause notice of the proposed payment of such Defaulted Interest and the Special Record Date therefor to be mailed, first-class postage prepaid, to each holder of a bond of the New Series Bonds at the address as it appears in the bond register not less than 10 days prior to such Special Record Date.  The Trustee may, in its discretion in the name and at the expense of the Company, cause a similar notice to be published at least once in a newspaper approved by the Company in each place of payment of the New Series Bonds, but such publication shall not be a condition precedent to the establishment of such Special Record Date .  Notice of the proposed payment of such Defaulted Interest and the Special Record Date therefor having been mailed as aforesaid, such Defaulted Interest shall be paid to the persons in whose names the New Series Bonds (or their respective predecessor bonds) are registered on such Special Record Date and shall no longer be payable pursuant to the following Subsection B.

B.            The Company may make payment of any Defaulted Interest on the New Series Bonds in any other lawful manner not inconsistent with the requirements of any securities exchange on which such bonds may be listed and upon such notice as may be required by such exchange, if, after notice given by the Company to the Trustee of the proposed payment pursuant to this Subsection, such payment shall be deemed practicable by the Trustee.

Subject to the foregoing provisions of this Section, each New Series Bond delivered under this Supplemental Indenture upon transfer of or in exchange for or in lieu of any other New Series Bonds shall carry all the rights to interest accrued and unpaid, and to accrue, which were carried by such other bond and each such bond shall bear interest from such date, that neither gain nor loss in interest shall result from such transfer, exchange or substitution.

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ARTICLE II

ADDITIONAL COVENANTS

The Company hereby covenants as follows:

Section 1.  That it will, prior to or simultaneously with the initial authentication and delivery by the Trustee of the New Series Bonds under Section 4.05 of the Original Indenture, deliver to the Trustee the instruments required by said Section.

Section 2.  That, so long as any of the New Series Bonds shall be outstanding, it will not declare or pay any dividends (except a dividend in its own common stock) upon its common stock, or make any other distribution (by way of purchase, or otherwise) to the holders thereof, except a payment or distribution out of net income of the Company subsequent to December 31, 1943; and that it will not permit any subsidiary of the Company to purchase any shares of common stock of the Company.  The terms (i) “dividend” shall be interpreted so as to include distributions and (ii) “common stock” and “shares of common stock” shall be interpreted so as to include membership interests.

For the purpose of this Section, net income of the Company shall be determined by regarding as charges or credits to income, as the case may be, any and all charges or credits to earned surplus subsequent to December 31, 1943, representing adjustments on account of excessive or deficient accruals to income for taxes, and operating expenses shall include all proper charges for the maintenance and repairs of the property owned by the Company and appropriations out of income for the retirement or depreciation of the property used in its electric business in an amount of not less than the amount of the minimum provision for depreciation determined as provided in clause (5) of paragraph A of Section 1.05 of the Original Indenture.

ARTICLE III

SUNDRY PROVISIONS

Section 1.  This Supplemental Indenture is executed and shall be construed as an indenture supplemental to the Original Indenture, and shall form a part thereof and all of the provisions contained in the Original Indenture in respect to the rights, privileges, immunities, powers and duties of the Trustee shall be applicable in respect hereof as fully and with like effect as if set forth herein in full .  The Trustee agrees to accept and act upon instructions or directions pursuant to this Supplemental Indenture sent by unsecured e-mail, facsimile transmission or other similar unsecured electronic methods, provided, however, that the Company shall provide to the Trustee an incumbency certificate listing designated persons authorized to provide such instructions, which incumbency certificate shall be amended whenever a person is to be added or deleted from the listing.  If the Company elects to give the Trustee e-mail or facsimile instructions pursuant to this Supplemental Indenture (or instructions by a similar electronic method) and the Trustee in its discretion elects to act upon such instructions, the Trustee’s understanding of such instructions shall be deemed controlling in the absence of manifest error .  Subject to Sections 14.02 and 14.03 of the Indenture, the Trustee shall not be liable for any losses, costs or expenses arising directly or indirectly from the Trustee’s reliance upon and compliance with such instructions notwithstanding whether such instructions conflict or are inconsistent with a subsequent written instruction.  Subject to Sections 14.02 and 14.03 of the Indenture, the Company agrees to assume all risks arising out of the use of such electronic methods to submit instructions and directions to the Trustee pursuant to this Supplemental Indenture, including without limitation the risk of the Trustee acting on unauthorized instructions, and the risk or interception and misuse by third parties.

Section 2.  This Supplemental Indenture may be simultaneously executed in any number of counterparts, and all of said counterparts executed and delivered, each as an original, shall constitute but one and the same instrument.

Section 3.  The Trustee shall not be responsible in any manner whatsoever for or in respect of the validity or sufficiency of this Supplemental Indenture or of the due execution hereof by the Company or for or in respect of the recitals contained herein, all of which recitals are made by the Company solely.

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Section 4.  Although this Supplemental Indenture is dated for convenience and for purposes of reference as of September 1, 2016, the actual dates of execution by the Company and by the Trustee are as indicated by the respective acknowledgments hereto annexed.

[signature page follows]

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IN WITNESS WHEREOF, DUKE ENERGY FLORIDA, LLC has caused this Supplemental Indenture to be signed in its name and behalf by its Assistant Treasurer, and its company seal to be hereunto affixed and attested by its Assistant Secretary, and THE BANK OF NEW YORK MELLON has caused this Supplemental Indenture to be signed and sealed in its name and behalf by a Vice President, and its company seal to be attested by a Vice President, all as of the day and year first above written.

[Company’s Signature Page of Fifty-Third Supplemental Indenture]

Before me, the undersigned, a notary public in and for the State and County aforesaid, an officer duly authorized to take acknowledgments of deeds and other instruments, personally appeared John L. Sullivan, III, Assistant Treasurer of DUKE ENERGY FLORIDA, LLC , a limited liability company, the limited liability company party of the first part in and to the above written instrument, and also personally appeared before me Robert T. Lucas III, Assistant Secretary of the said limited liability company; such persons being severally personally known to me, who did take an oath and are known by me to be the same individuals who as such Assistant Treasurer and as such Assistant Secretary executed the above written instrument on behalf of said limited liability company; and he, the said Assistant Treasurer, acknowledged that as such Assistant Treasurer, he subscribed the said company name to said instrument on behalf and by authority of said limited liability company, and he, the said Assistant Secretary, acknowledged that he affixed the seal of said limited liability company to said instrument and attested the same by subscribing his name as Assistant Secretary of said limited liability company, by authority and on behalf of said limited liability company, and each of the two persons above named acknowledged that, being informed of the contents of said instrument, they, as such Assistant Treasurer and Assistant Secretary, delivered said instrument by authority and on behalf of said limited liability company and that all such acts were done freely and voluntarily and for the uses and purposes in said instrument set forth and that such instrument is the free act and deed of said limited liability company; and each of said persons further acknowledged and declared that he/she knows the seal of said limited liability company, and that the seal affixed to said instrument is the company seal of the limited liability company aforesaid.

IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official seal this 9th day of September, 2016 at Charlotte in the State and County aforesaid.

Before me, the undersigned, a notary public in and for the State of New York, an officer duly authorized to take acknowledgments of deeds and other instruments, personally appeared Francine Kincaid, Vice President (the “Executing Vice President”) of THE BANK OF NEW YORK MELLON , a New York banking corporation, the corporate party of the second part in and to the above written instrument, and also personally appeared before me Thomas Hacker, Vice President (the “Attesting Vice President”) of the said corporation; said persons being severally personally known to me, who did take an oath and are known by me to be the same individuals who as such Executing Vice President and as such Attesting Vice President executed the above written instrument on behalf of said corporation; and she, the said Executing Vice President, acknowledged that as such Executing Vice President she subscribed the said corporate name to said instrument and affixed the seal of said corporation to said instrument on behalf and by authority of said corporation, and he, the said Attesting Vice President, acknowledged that he attested the same by subscribing his name as Vice President of said corporation, by authority and on behalf of said corporation, and each of the two persons above named acknowledged that, being informed of the contents of said instrument, they, as such Executing Vice President and Attesting Vice President, delivered said instrument by authority and on behalf of said corporation and that all such acts were done freely and voluntarily and for the uses and purposes in said instrument set forth and that such instrument is the free act and deed of said corporation, and each of said persons further acknowledged and declared that he knows the seal of said corporation, and that the seal affixed to said instrument is the corporate seal of the corporation aforesaid.

IN WITNESS WHEREOF, I have hereunto set my hand and affixed my official seal this 7th day of September, 2016, at New York, in the State and County aforesaid.

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