Exhibit 3.1

EXHIBIT A

AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

DUKE ENERGY CORPORATION

DUKE ENERGY CORPORATION, a corporation organized and existing under the laws of the State of Delaware (the “Corporation”), DOES HEREBY CERTIFY AS FOLLOWS:

1. The name of the corporation is Duke Energy Corporation.  The name under which the corporation was originally incorporated was Deer Holding Corp.  The name of the corporation was changed to Duke Energy Holding Corp. on June 21, 2005.  The original Certificate of Incorporation was filed with the Secretary of State of the State of Delaware on May 3, 2005.

2. This Amended and Restated Certificate of Incorporation, having been duly adopted in accordance with Sections 242 and 245 of the General Corporation Law of the State of Delaware (the “DGCL”) and by the approval of the stockholders of the Corporation in accordance with Section 211 of the DGCL, restates and integrates and further amends the provisions of the Amended and Restated Certificate of Incorporation as amended or supplemented heretofore.  As so restated and integrated and further amended, the Amended and Restated Certificate of Incorporation (hereinafter, this “Certificate of Incorporation”) reads as follows:

ARTICLE FIRST

Name

The name of the corporation is Duke Energy Corporation.

ARTICLE SECOND

Registered Office

The address of the registered office of the Corporation in the State of Delaware is 1209 Orange Street, City of Wilmington, County of New Castle. The name of the registered agent of the Corporation at such address is The Corporation Trust Company.

ARTICLE THIRD

Purpose

The purpose of the Corporation is to engage in any lawful act or activity for which a corporation may be organized under the DGCL.

ARTICLE FOURTH

Capital Stock

(a) The aggregate number of shares of stock that the Corporation shall have authority to issue is two billion forty-four million (2,044,000,000) shares, consisting of two billion (2,000,000,000) shares of Common Stock, par value $0.001 per share (the “Common Stock”), and forty-four million (44,000,000) shares of Preferred Stock, par value $0.001 per share (the “Preferred Stock”).

(b) The Board of Directors of the Corporation shall have the full authority permitted by law, at any time and from time to time, to divide the authorized and unissued shares of Preferred Stock into one or more classes or series and, with respect to each such class or series, to determine by resolution or resolutions the number of shares constituting such class or series and the designation of such class or series, the voting powers, if any, of the shares of such class or series, and the preferences and relative, participating, optional or other special rights, if any, and any qualifications, limitations or restrictions thereof, of the shares of any such class or series of Preferred Stock to the full extent now or hereafter permitted by the law of the State of Delaware. The powers, preferences and relative, participating, optional and other special rights of each class or series of Preferred Stock and the qualifications, limitations or restrictions thereof, if any, may differ from those of any and all other classes or series at any time outstanding.

(c) Subject to applicable law and the rights, if any, of the holders of any class or series of Preferred Stock or any class or series of stock having a preference over or the right to participate with the Common Stock with respect to the payment of dividends, dividends may be declared and paid on the Common Stock at such times and in such amounts as the Board of Directors of the Corporation in its discretion shall determine. Nothing in this ARTICLE FOURTH shall limit the power of the Board of Directors to create a class or series of Preferred Stock with dividends the rate of which is calculated by reference to, and the payment of which is concurrent with, dividends on shares of Common Stock.

(d) In the event of the voluntary or involuntary liquidation, dissolution or winding up of the Corporation, subject to the rights of the holders of any class or series of the Preferred Stock, the net assets of the Corporation available for distribution to stockholders of the Corporation shall be distributed pro rata to the holders of the Common Stock in accordance with their respective rights and interests. If the assets of the Corporation are not sufficient to pay the amounts, if any, owing to holders of shares of Preferred Stock in full, holders of all shares of Preferred Stock will participate in the

distribution of assets ratably in proportion to the full amounts to which they are entitled or in such order or priority, if any, as will have been fixed in the resolution or resolutions providing for the issue of the class or series of Preferred Stock. Neither the merger or consolidation of the Corporation into or with any other corporation, nor a sale, transfer or lease of all or part of its assets, will be deemed a liquidation, dissolution or winding up of the Corporation within the meaning of this paragraph, except to the extent specifically provided in any certificate of designation for any class or series of Preferred Stock. Nothing in this ARTICLE FOURTH shall limit the power of the Board of Directors to create a class or series of Preferred Stock for which the amount to be distributed upon any liquidation, dissolution or winding up of the Corporation is calculated by reference to, and the payment of which is concurrent with, the amount to be distributed to the holders of shares of Common Stock.

(e) Except as otherwise required by law, as otherwise provided herein or as otherwise determined by the Board of Directors as to the shares of any class or series of Preferred Stock, the holders of Preferred Stock shall have no voting rights and shall not be entitled to any notice of meetings of stockholders.

(f) Except as otherwise required by law and subject to the rights of the holders of any class or series of Preferred Stock, with respect to all matters upon which stockholders are entitled to vote or to which stockholders are entitled to give consent, the holders of any outstanding shares of Common Stock shall vote together as a class, and every holder of Common Stock shall be entitled to cast thereon one vote in person or by proxy for each share of Common Stock standing in such holder’s name on the books of the Corporation; provided, however, that, except as otherwise required by law, or unless provided in any certificate of designation for any class or series of Preferred Stock, holders of Common Stock, as such, shall not be entitled to vote on any amendment to this Certificate of Incorporation (including any certificate of designations relating to any class or series of Preferred Stock) that relates solely to the terms of one or more outstanding classes or series of Preferred Stock if the holders of such affected class or series are entitled, either separately or together with the holders of one or more other such classes or series, to vote thereon pursuant to this Certificate of Incorporation (including any certificate of designations relating to any class or series of Preferred Stock) or pursuant to applicable law.  Subject to the rights of the holders of any class or series of Preferred Stock, stockholders of the Corporation shall not have any preemptive rights to subscribe for additional issues of stock of the Corporation and no stockholder will be permitted to cumulate votes at any election of directors.

ARTICLE FIFTH

Board of Directors

(a) The business and affairs of the Corporation shall be managed by or under the direction of the Board of Directors.

(b) Except as otherwise fixed by or pursuant to provisions of ARTICLE FOURTH relating to the rights of the holders of any series of Preferred Stock, the number of directors of the Corporation shall not be less than nine (9) nor more than eighteen (18), as may be fixed from time to time by the Board of Directors.

(c) A director may be removed from office with or without cause; provided, however, that, subject to applicable law, any director elected by the holders of any series of Preferred Stock may be removed without cause only by the holders of a majority of the shares of such series of Preferred Stock.

(d) Except as otherwise fixed by or pursuant to provisions of ARTICLE FOURTH relating to the rights of the holders of any series of Preferred Stock, newly created directorships resulting from any increase in the number of directors and any vacancies on the Board of Directors resulting from death, resignation, disqualification, removal or other cause shall be filled only by the affirmative vote of a majority of the remaining directors then in office, even though less than a quorum of the Board of Directors.  Any director elected in accordance with the preceding sentence shall hold office until the next succeeding annual meeting of stockholders and until his or her successor shall be elected and shall qualify, subject, however, to prior death, resignation, retirement, disqualification or removal from office.  No decrease in the number of directors constituting the Board of Directors shall shorten the term of any incumbent director.

(e) Except as otherwise fixed by or pursuant to provisions of ARTICLE FOURTH relating to the rights of the holders of any series of Preferred Stock, the directors shall be elected by the holders of voting stock and shall hold office until the next annual meeting of stockholders and until their respective successors shall have been duly elected and qualified, subject, however, to prior death, resignation, retirement, disqualification or removal from office.

(f) Election of directors need not be by written ballot unless the By-Laws so provide.

(g) In addition to the powers and authority hereinbefore or by statute expressly conferred upon them, the directors are hereby empowered to exercise all such powers and do all such acts and things as may be exercised or done by the Corporation, subject, nevertheless, to the provisions of the DGCL, this Certificate of Incorporation, and any By-Laws adopted by the stockholders; provided, however, that no By-Laws hereafter adopted by the stockholders shall invalidate any prior act of the directors which would have been valid if such By-Laws had not been adopted.

ARTICLE SIXTH

Action by Stockholders; Books of the Corporation

(a) Meetings of stockholders may be held within or without the State of Delaware, as the By-Laws may provide. The books of the Corporation may be kept (subject to any provision contained in the DGCL) outside the State of Delaware at such place or places as may be designated from time to time by the Board of Directors or in the By-Laws of the Corporation.

(b) Written Consent.   Certain actions required or permitted to be taken by the stockholders of the Corporation at an annual or special meeting of the stockholders may be effected without a meeting by the written consent of the holders of common stock of the Corporation (a “Consent”), but only if such action is taken in accordance with the provisions of this Article Sixth, the Corporation’s By-laws and applicable law.

(i)                                     Record Date.  The record date for determining such stockholders entitled to consent to corporate action in writing without a meeting shall be as fixed by the Board of Directors or as otherwise established under this Article Sixth.  Any holder of common stock of the Corporation seeking to have the stockholders authorize or take corporate action by Consent shall, by written request addressed to the secretary of the Corporation and delivered to the Corporation’s principal executive offices and signed by holders of record at the time such request is delivered representing at least 20 percent (20%) of the outstanding shares of common stock of the Corporation, request that a record date be fixed for such purpose.  The written request must contain the information set forth in paragraph (b)(ii) of this Article Sixth.  Following delivery of the request, the Board of Directors shall, by the later of (x) 20 days after delivery of a valid request to set a record date and (y) 5 days after delivery of any information required by the Corporation to determine the validity of the request for a record date or to determine whether the action to which the request relates may be effected by Consent under paragraph (b)(iii) of this Article Sixth, determine the validity of the request and whether the request relates to an action that may be taken by Consent and, if appropriate, adopt a resolution fixing the record date for such purpose.  The record date for such purpose shall be no more than 10 days after the date upon which the resolution fixing the record date is adopted by the Board of Directors and shall not precede the date such resolution is adopted.  If a request complying with the second and third sentences of this paragraph (b)(i) has been delivered to the secretary of the Corporation but no record date has been fixed by the Board of Directors by the date required by the preceding sentence, the record date shall be the first date on which a signed Consent relating to the action taken or proposed to be taken by Consent is delivered to the Corporation in the manner described in paragraph (b)(vi) of this Article Sixth; provided that, if prior action by the Board of Directors is required under the provisions of Delaware law, the record date shall be at the close of business on the day on which the Board of Directors adopts the resolution taking such prior action.

(ii)                                  Request Requirements.  Any request required by paragraph (b)(i) of this Article Sixth (a) must be delivered by the holders of record of at least 20% of the outstanding shares of common stock of the,

who shall not revoke such request and who shall continue to own not less than 20% of the outstanding shares of common stock of the Corporation through the date of delivery of Consents signed by a sufficient number of stockholders to authorize or take such action; (b) must contain an agreement to solicit Consents in accordance with paragraph (b)(iv) of this Article Sixth, (c) must describe the action proposed to be taken by written consent of stockholders and (d) must contain (1) such information and representations, to the extent applicable, then required by Section 2.03(b) of the Corporation’s By-laws as though such stockholder was intending to propose an amendment to the Corporation’s Restated Certificate of Incorporation or By-laws or other business to be brought before a meeting of stockholders and (2) the text of the proposed action to be taken (including the text of any resolutions to be adopted by Consent) and (e) must include documentary evidence that the requesting stockholder(s) own in the aggregate not less than 20% of the outstanding shares of common stock of the Corporation as of the date of such written request to the secretary; provided, however, that if the stockholder(s) making the request are not the beneficial owners of the shares representing at least 20% of the outstanding shares of common stock of the Corporation, then to be valid, the request must also include documentary evidence (or, if not simultaneously provided with the request, such documentary evidence must be delivered to the secretary within ten business days after the date on which the request is delivered to the secretary) that the beneficial owners on whose behalf the request is made beneficially own at least 20% of the outstanding shares of common stock of the Corporation as of the date on which such request is delivered to the secretary.  If the action proposes to elect directors by written consent, the written request for a record date must also contain the information required by Section 3.03 of the Corporation’s By-laws.  The Corporation may require the stockholder(s) submitting such request to furnish such other information as may be reasonably requested by the Corporation.  Any requesting stockholder may revoke his, her or its request at any time by written revocation delivered to the secretary of the Corporation at the Corporation’s principal executive offices.  Any disposition by a requesting stockholder of any shares of common stock of the Corporation (or of beneficial ownership of such shares by the beneficial owner on whose behalf the request was made) after the date of the request, shall be deemed a revocation of the request with respect to such shares, and each requesting stockholder and the applicable beneficial owner shall certify to the secretary of the Corporation on the day prior to the record date set for the action by written consent as to whether any such disposition has occurred. If the unrevoked requests represent in the aggregate less than 20% of the outstanding shares of common stock of the

Corporation, the Board of Directors, in its discretion, may cancel the action by written consent.

(iii)                               Actions Which May Be Taken by Written Consent.  Stockholders are not entitled to act by Consent if (a) the record date request does not comply with this Article Sixth or the Corporation’s By-Laws; (b) the action relates to an item of business that is not a proper subject for stockholder action under applicable law; (c) the request for a record date for such action is received by the Corporation during the period commencing 90 days prior to the first anniversary of the date of the immediately preceding annual meeting and ending on the date of the next annual meeting; (d) an identical or substantially similar item of business (as determined by the Board of Directors of the Corporation in its reasonable determination, which determination shall be conclusive and binding on the Corporation and its stockholders, (a “Similar Item”)), was presented at a meeting of stockholders held not more than 12 months before the request is received by the secretary of the Corporation; (e) a Similar Item consisting of the election or removal of directors was presented at a meeting of stockholders held not more than 90 days before the request is received by the secretary of the Corporation (and, for purposes of this clause, the election or removal of directors shall be deemed a “Similar Item” with respect to all items of business involving the election or removal of directors), (f) a Similar Item is included in the Corporation’s notice of meeting as an item of business to be brought before an annual or special stockholders meeting that has been called but not yet held or that is called to be held within 90 days after the request is received by the secretary of the Corporation; or (g) such record date request was made in a manner that involved a violation of Regulation 14A under the Securities Exchange Act of 1934 or other applicable law.  For purposes of this paragraph (b)(iii), the nomination, election or removal of directors shall be deemed to be a Similar Item with respect to all actions involving the nomination, election or removal of directors, changing the size of the Board of Directors and filling of vacancies and/or newly created directorships resulting from any increase in the authorized number of directors.

(iv)                              Manner of Consent Solicitation.  Holders of common stock of the Corporation may take action by written consent only if Consents are solicited from all holders of common stock of the Corporation entitled to vote on the matter and in accordance with applicable law.

(v)                                 Date of Consent.  Every Consent purporting to take or authorize the taking of corporate action must bear the date of signature of each stockholder who manually signs the Consent, and no Consent shall be effective to take the corporate action referred to therein unless,

within 60 days of the earliest dated Consent delivered in the manner required by paragraph (b)(vi) of this Article Sixth and not later than 120 days after the record date, Consents signed by a sufficient number of stockholders to take such action are so delivered to the Corporation.

(vi)                              Delivery of Consents.  No Consents may be dated or delivered to the Corporation or its registered office in the State of Delaware until 60 days after the delivery of a valid request to set a record date.  Consents must be delivered to the Corporation by delivery to its registered office in the State of Delaware or its principal place of business.  Delivery must be made by hand or by certified or registered mail, return receipt requested.  The secretary of the Corporation shall provide for the safe-keeping of such Consents and any related revocations and shall promptly designate one or more persons, who shall not be members of the Board of Directors, to serve as inspectors (“Inspectors”) with respect to such Consents.  The Inspectors shall promptly conduct a ministerial review of the sufficiency of all Consents and any related revocations and of the validity of the action to be taken by written consent as the secretary of the Corporation deems necessary or appropriate, including, without limitation, whether the stockholders of a number of shares having the requisite voting power to authorize or take the action specified in Consents have given consent.  If after such investigation the Inspectors shall determine that the action purported to have been taken is duly authorized by the Consents, that fact shall be certified on the records of the Corporation kept for the purpose of recording the proceedings of meetings of stockholders and the Consents shall be filed in such records.  In conducting the investigation required by this section, the Inspectors of the Corporation may, at the expense of the Corporation, retain special legal counsel and any other necessary or appropriate professional advisors as such person or persons may deem necessary or appropriate and, to the fullest extent permitted by law, shall be fully protected in relying in good faith upon the opinion of such counsel or advisors.

(vii)                           Effectiveness of Consent.  No action may be taken by the stockholders by Consent except in accordance with this Article Sixth.  If the Board of Directors shall determine that any request to fix a record date was not properly made in accordance with, or relates to an action that may not be effected by Consent pursuant to, this Article Sixth, or the stockholder or stockholders seeking to take such action do not otherwise comply with this Article Sixth, then the Board of Directors shall not be required to fix a record date and any such purported action by Consent shall be null and void to the fullest extent permitted by applicable law.  No Consent shall be effective until such date as the Inspectors certify to the Corporation

that the Consents delivered to the Corporation in accordance with paragraph (vi) of this Article Sixth, represent at least the minimum number of votes that would be necessary to take the corporate action at a meeting at which all shares entitled to vote thereon were present and voted, in accordance with Delaware law and this Certificate of Incorporation.

(viii)                        Challenge to Validity of Consent.  Nothing contained in this Article Sixth shall in any way be construed to suggest or imply that the Board of Directors of the Corporation or any stockholder shall not be entitled to contest the validity of any Consent or related revocations, whether before or after such certification by the Inspectors, as the case may be, or to prosecute or defend any litigation with respect thereto.

(ix)                              Board-solicited Stockholder Action by Written Consent.  Notwithstanding anything to the contrary set forth above, (x) none of the foregoing provisions of this Article Sixth shall apply to any solicitation of stockholder action by written consent by or at the direction of the Board of Directors and (y) the Board of Directors shall be entitled to solicit stockholder action by written consent in accordance with applicable law.

ARTICLE SEVENTH

Amendment of Certificate of Incorporation

The Corporation reserves the right to supplement, amend, alter, change or repeal any provision contained in this Certificate of Incorporation, in the manner now or hereafter prescribed by the laws of the State of Delaware and this Certificate of Incorporation, and all rights conferred upon stockholders, directors and officers herein are granted subject to this reservation. Notwithstanding the foregoing, this ARTICLE SEVENTH and sections (b) and (d) of ARTICLE FIFTH may not be supplemented, amended, altered, changed, or repealed in any respect, nor may any provision inconsistent therewith be adopted, unless such supplement, amendment, alteration, change or repeal is approved by the affirmative vote of the holders of at least 80% of the combined voting power of the then outstanding shares of stock of all classes of the Corporation entitled to vote generally in the election of directors, voting together as a single class.

ARTICLE EIGHTH

Amendment of By-Laws

In furtherance and not in limitation of the powers conferred upon it by law, the Board of Directors of the Corporation is expressly authorized to adopt, repeal, alter or amend the By-Laws of the Corporation. No By-Laws may be adopted, repealed, altered or amended in any manner that would be inconsistent with this Amended and Restated Certificate of Incorporation (as it may be adopted, repealed, altered or amended from time to time in accordance with ARTICLE SEVENTH).

ARTICLE NINTH

Limitation of Liability

Except to the extent elimination or limitation of liability is not permitted by applicable law, no director of the Corporation shall be personally liable to the Corporation or its stockholders for monetary damages for any breach of fiduciary duty in such capacity. Any repeal or modification of this ARTICLE NINTH by the stockholders of the Corporation shall not adversely affect any right or protection of a director of the Corporation existing at the time of such repeal or modification with respect to acts or omissions occurring prior to such repeal or modification.

ARTICLE TENTH

Liability of Stockholders

The holders of the capital stock of the Corporation shall not be personally liable for the payment of the Corporation’s debts, and the private property of the holders of the capital stock of the Corporation shall not be subject to the payment of debts of the Corporation to any extent whatsoever.

ARTICLE ELEVENTH

Effectiveness

This Amended and Restated Certificate of Incorporation is to become effective at 12:01 a.m. on May 20, 2014.

IN WITNESS WHEREOF, THE UNDERSIGNED, being the Assistant Corporate Secretary, has executed this Amended and Restated Certificate of Incorporation as of the 19th day of May, 2014, and DOES HEREBY CERTIFY under the penalties of perjury that the facts stated in this Amended and Restated Certificate of Incorporation are true.