Exhibit 3.1

AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

of

ALTENERGY ACQUISITION CORP.

(Pursuant to Sections 242 and 245 of the

General Corporation Law of the State of Delaware)

AltEnergy Acquisition Corp., a corporation organized and existing under and by virtue of the provisions of the General Corporation Law of the State of Delaware (the “DGCL”),

DOES HEREBY CERTIFY:

1. That the name of this corporation is AltEnergy Acquisition Corp., and that this corporation was originally incorporated pursuant to the DGCL on February 9, 2021 under the name AltEnergy Acquisition Corp.

2. This Amended and Restated Certificate of Incorporation (this “Certificate”) was duly adopted in accordance with Sections 103, 242 and 245 of the DGCL.

RESOLVED, that the Amended and Restated Certificate of Incorporation of this Corporation be amended and restated in its entirety to read as follows:

ARTICLE I

NAME

The name of the corporation is AltEnergy Acquisition Corp. (the “Corporation”).

ARTICLE II

REGISTERED AGENT

The street address of the initial registered office of the Corporation in the State of Delaware is 251 Little Falls Drive, Wilmington, New Castle County, Delaware, 19808, and the name of the Corporation’s initial registered agent at such address is Corporation Service Company.

ARTICLE III

PURPOSE

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

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ARTICLE IV ARTICLE IV

CAPITALIZATION

Section 4.1 Authorized Capital Stock. The total number of shares of all classes of capital stock which the Corporation is authorized to issue is 111,000,000 shares, consisting of (a) 110,000,000 shares of common stock, par value $0.0001 per share (the “Common Stock”), including (i) 100,000,000 shares of Class A Common Stock (the “Class A Common Stock”) and (ii) 10,000,000 shares of Class B Common Stock (the “Class B Common Stock”), and (b) 1,000,000 shares of preferred stock, par value $0.0001 per share (the “Preferred Stock”). The powers, preferences and relative, participating, optional and other special rights of the respective classes of the Corporation’s capital stock or the holders thereof and the qualifications, limitations and restrictions thereof are set forth below.

Section 4.2 Preferred Stock.

(a) The Preferred Stock may be issued in one or more series from time to time, with each such series to consist of such number of shares and to have such voting powers, full or limited, or no voting powers, and such designations, preferences and relative, participating, optional or other special rights, and the qualifications, limitations or restrictions thereof, as shall be stated in the resolution or resolutions providing for the issuance of such series adopted by the board of directors of the Corporation (the “Board”) and included in a certificate of designations (a “Preferred Stock Designation”) filed pursuant to the DGCL, and the Board is hereby expressly vested with the authority, to the full extent now or hereafter provided by law, to adopt any such resolution or resolutions.

(b) The number of authorized shares of Preferred Stock may be increased or decreased (but not below the number of shares thereof then outstanding) by the affirmative vote of the holders of a majority of the outstanding shares of Common Stock, without a vote of the holders of the Preferred Stock, or any series thereof, unless a vote of any such holders of Preferred Stock is required pursuant to another provision of this Certificate, including any Preferred Stock Designation.

Section 4.3 Common Stock.

(a) Voting.

(1) Except as otherwise required by law or this Certificate (including any Preferred Stock Designation), the holders of the Common Stock shall exclusively possess all voting power with respect to the Corporation.

(2) Except as otherwise required by law or this Certificate (including any Preferred Stock Designation), the holders of shares of Common Stock shall be entitled to one vote for each such share on each matter properly submitted to the stockholders on which the holders of the Common Stock are entitled to vote.

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(3) Except as otherwise required by law or this Certificate (including any Preferred Stock Designation), at any annual or special meeting of the stockholders of the Corporation, holders of the Class A Common Stock and holders of the Class B Common Stock, voting together as a single class, shall have the exclusive right to vote for the election of directors and on all other matters properly submitted to a vote of the stockholders. Notwithstanding the foregoing, except as otherwise required by law or this Certificate (including any Preferred Stock Designation), holders of shares of any series of Common Stock shall not be entitled to vote on any amendment to this Certificate (including any amendment to any Preferred Stock Designation) that relates solely to the terms of one or more outstanding series of Preferred Stock or other series of Common Stock if the holders of such affected series of Preferred Stock or Common Stock, as applicable, are entitled, either separately or together with the holders of one or more other such series, to vote thereon pursuant to this Certificate (including any Preferred Stock Designation) or the DGCL.

(b) Class B Common Stock.

(1) Shares of Class B Common Stock shall be convertible into shares of Class A Common Stock on a one-for-one basis (the “Initial Conversion Ratio”) (A) at any time and from time to time at the option of the holder thereof and (B) automatically on the business day following the closing of the Business Combination (as defined below).

(2) Notwithstanding the Initial Conversion Ratio, in the case that additional shares of Class A Common Stock or equity-linked securities are issued or deemed issued in excess of the amounts sold in the Corporation’s initial public offering of securities (the “Offering”) and related to or in connection with the closing of the Corporation’s initial merger, capital stock exchange, asset acquisition, stock purchase, reorganization or similar business combination with one or more businesses (the “Business Combination”), all issued and outstanding shares of Class B Common Stock shall automatically convert into shares of Class A Common Stock at the time of the closing of the Corporation’s initial Business Combination, the ratio for which the shares of Class B Common Stock shall convert into shares of Class A Common Stock will be adjusted so that the number of shares of Class A Common Stock issuable upon conversion of all shares of Class B Common Stock will equal, in the aggregate, 20% of the sum of (a) the total number of all shares of Common Stock outstanding upon the completion of the Offering (not including the shares of Class A Common Stock underlying the private placement warrants sold in connection with the Offering) plus (b) all shares of Class A Common Stock and equity-linked securities issued or deemed issued in connection with the initial Business Combination (excluding any shares of Class A Common Stock or equity-linked securities issued, or to be issued, to any seller in the initial Business Combination, any private placement-equivalent warrants issued to AltEnergy Acquisition Sponsor, LLC (the “Sponsor”) or its affiliates upon conversion of loans made to the Corporation).

Notwithstanding anything to the contrary contained herein, (i) the foregoing adjustment to the Initial Conversion Ratio may be waived as to any particular issuance or deemed issuance of additional shares of Class A Common Stock or equity-linked securities by the written consent or agreement of holders of a majority of the shares of Class B Common Stock then outstanding consenting or agreeing separately as a single class in the manner provided in Section 4.3(a)(3), and (ii) in no event shall the Class B Common Stock convert into Class A Common Stock at a ratio that is less than one-for-one.

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The foregoing conversion ratio shall also be adjusted to account for any subdivision (by stock split, subdivision, exchange, stock dividend, reclassification, recapitalization or otherwise) or combination (by reverse stock split, exchange, reclassification, recapitalization or otherwise) or similar reclassification or recapitalization of the outstanding shares of Class A Common Stock into a greater or lesser number of shares occurring after the original filing of this Certificate without a proportionate and corresponding subdivision, combination or similar reclassification or recapitalization of the outstanding shares of Class B Common Stock.

Each share of Class B Common Stock shall convert into its pro rata number of shares of Class A Common Stock pursuant to this Section 4.3(b). The pro rata share for each holder of Class B Common Stock will be determined as follows: Each share of Class B Common Stock shall convert into such number of shares of Class A Common Stock as is equal to the product of one (1) multiplied by a fraction, the numerator of which shall be the total number of shares of Class A Common Stock into which all of the issued and outstanding shares of Class B Common Stock shall be converted pursuant to this Section 4.3(b) and the denominator of which shall be the total number of issued and outstanding shares of Class B Common Stock at the time of conversion.

(3) Voting. Except as otherwise required by law or this Certificate (including any Preferred Stock Designation), for so long as any shares of Class B Common Stock shall remain outstanding, the Corporation shall not, without the prior vote or written consent of the holders of a majority of the shares of Class B Common Stock then outstanding, voting separately as a single class, amend, alter or repeal any provision of this Certificate, whether by merger, consolidation or otherwise, if such amendment, alteration or repeal would alter or change the powers, preferences or relative, participating, optional or other or special rights of the Class B Common Stock. Any action required or permitted to be taken at any meeting of the holders of Class B Common Stock may be taken without a meeting, without prior notice and without a vote, if a consent or consents in writing, setting forth the action so taken, shall be signed by the holders of the outstanding Class B Common Stock having not less than the minimum number of votes that would be necessary to authorize or take such action at a meeting at which all shares of Class B Common Stock were present and voted and shall be delivered to the Corporation by delivery to its registered office in the State of Delaware, its principal place of business, or an officer or agent of the Corporation having custody of the book in which minutes of proceedings of stockholders are recorded. Delivery made to the Corporation’s registered office shall be by hand or by certified or registered mail, return receipt requested. Prompt written notice of the taking of corporate action without a meeting by less than unanimous written consent of the holders of Class B Common Stock shall, to the extent required by law, be given to those holders of Class B Common Stock who have not consented in writing and who, if the action had been taken at a meeting, would have been entitled to notice of the meeting if the record date for notice of such meeting had been the date that written consents signed by a sufficient number of holders of Class B Common Stock to take the action were delivered to the Corporation.

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(c) Dividends. Subject to applicable law, the rights, if any, of the holders of any outstanding series of the Preferred Stock, the holders of shares of Common Stock shall be entitled to receive such dividends and other distributions (payable in cash, property or capital stock of the Corporation) when, as and if declared thereon by the Board from time to time out of any assets or funds of the Corporation legally available therefor and shall share equally on a per share basis in such dividends and distributions.

(d) Liquidation, Dissolution or Winding Up of the Corporation. Subject to applicable law, the rights, if any, of the holders of any outstanding series of the Preferred Stock, in the event of any voluntary or involuntary liquidation, dissolution or winding up of the Corporation, after payment or provision for payment of the debts and other liabilities of the Corporation, the holders of shares of Common Stock shall be entitled to receive all the remaining assets of the Corporation available for distribution to its stockholders, ratably in proportion to the number of shares of Class A Common Stock (on an as converted basis with respect to the Class B Common Stock) held by them.

Section 4.4 Rights and Options. The Corporation has the authority to create and issue rights, warrants and options entitling the holders thereof to acquire from the Corporation any shares of its capital stock of any class or classes, with such rights, warrants and options to be evidenced by or in instrument(s) approved by the Board. The Board is empowered to set the exercise price, duration, times for exercise and other terms and conditions of such rights, warrants or options; provided, however, that the consideration to be received for any shares of capital stock issuable upon exercise thereof may not be less than the par value thereof.

ARTICLE V

DIRECTORS

Section 5.1 Board Powers. The business and affairs of the Corporation shall be managed by, or under the direction of, the Board. In addition to the powers and authority expressly conferred upon the Board by statute, this Certificate or the By Laws (the “By Laws”) of the Corporation, the Board is 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 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 Board that would have been valid if such By Laws had not been adopted.

Section 5.2 Number, Election and Term.

(a) The number of directors of the Corporation, other than those who may be elected by the holders of one or more series of the Preferred Stock voting separately by class or series, shall be fixed from time to time exclusively by the Board pursuant to a resolution adopted by a majority of the Board.

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(b) Subject to Section 5.5 hereof, the Board shall be divided into three classes, as nearly equal in number as possible and designated Class I, Class II and Class III. The Board is authorized to assign members of the Board already in office to Class I, Class II or Class III. The term of the initial Class I Directors shall expire at the first annual meeting of the stockholders of the Corporation following the effectiveness of this Certificate, the term of the initial Class II Directors shall expire at the second annual meeting of the stockholders of the Corporation following the effectiveness of this Certificate, and the term of the initial Class III Directors shall expire at the third annual meeting of the stockholders of the Corporation following the effectiveness of this Certificate. At each succeeding annual meeting of the stockholders of the Corporation, beginning with the first annual meeting of the stockholders of the Corporation following the effectiveness of this Certificate, each of the successors elected to replace the class of directors whose term expires at that annual meeting shall be elected for a three-year term or until the election and qualification of their respective successors in office, subject to their earlier death, resignation or removal. Subject to Section 5.5 hereof, if the number of directors that constitute the Board is changed, any increase or decrease shall be apportioned by the Board among the classes so as to maintain the number of directors in each class as nearly equal as possible, but in no case shall a decrease in the number of directors constituting the Board shorten the term of any incumbent director. Subject to the rights of the holders of one or more series of Preferred Stock, voting separately by class or series, to elect directors pursuant to the terms of one or more series of Preferred Stock, the election of directors shall be determined by a plurality of the votes cast by the stockholders present in person or represented by proxy at the meeting and entitled to vote thereon. The Board is hereby expressly authorized, by resolution or resolutions thereof, to assign members of the Board already in office to the aforesaid classes at the time this Certificate (and therefore such classification) becomes effective in accordance with the DGCL.

(c) Subject to Section 5.5 hereof, a director shall hold office until the annual meeting for the year in which his or her term expires and until his or her successor has been elected and qualified, subject, however, to such director’s earlier death, resignation, retirement, disqualification or removal.

(d) Unless and except to the extent that the By-Laws shall so require, the election of directors need not be by written ballot. The holders of shares of Common Stock shall not have cumulative voting rights with regard to election of directors.

Section 5.3 Newly Created Directorships and Vacancies. Subject to Section 5.5 hereof, newly created directorships resulting from an increase in the number of directors and any vacancies on the Board resulting from death, resignation, retirement, disqualification, removal or other cause may be filled solely and exclusively by a majority vote of the remaining directors then in office, even if less than a quorum, or by a sole remaining director (and not by stockholders), and any director so chosen shall hold office for the remainder of the full term of the class of directors to which the new directorship was added or in which the vacancy occurred and until his or her successor has been elected and qualified, subject, however, to such director’s earlier death, resignation, retirement, disqualification or removal.

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Section 5.4 Removal. Subject to Section 5.5 hereof, any or all of the directors may be removed from office at any time, but only for cause and only by the affirmative vote of holders of a majority of the voting power of all then outstanding shares of capital stock of the Corporation entitled to vote generally in the election of directors, voting together as a single class.

Section 5.5 Preferred Stock—Directors. Notwithstanding any other provision of this ARTICLE V, and except as otherwise required by law, whenever the holders of one or more series of the Preferred Stock shall have the right, voting separately by class or series, to elect one or more directors, the term of office, the filling of vacancies, the removal from office and other features of such directorships shall be governed by the terms of such series of the Preferred Stock as set forth in this Amended and Restated Certificate (including any Preferred Stock Designation) and such directors shall not be included in any of the classes created pursuant to this Article V unless expressly provided by such terms.

ARTICLE VI

BY LAWS

In furtherance and not in limitation of the powers conferred upon it by law, the Board shall have the power to adopt, amend, alter or repeal the By Laws. The By Laws also may be adopted, amended, altered or repealed by the stockholders.

ARTICLE VII

LIMITED LIABILITY; INDEMNIFICATION

Section 7.1 Limitation of Personal Liability. No person who is or was a director of the Corporation shall be personally liable to the Corporation or any of its stockholders for monetary damages for breach of fiduciary duty as a director, except to the extent such exemption from liability or limitation thereof is not permitted by the DGCL as the same exists or hereafter may be amended. If the DGCL is hereafter amended to authorize corporate action further limiting or eliminating the liability of directors, then the liability of a director to the Corporation or its stockholders shall be limited or eliminated to the fullest extent permitted by the DGCL, as so amended. Any repeal or amendment of this Section 7.1 by the stockholders of the Corporation or by changes in law, or the adoption of any other provision of this Certificate inconsistent with this Section 7.1 will, unless otherwise required by law, be prospective only (except to the extent such amendment or change in law permits the Corporation to further limit or eliminate the liability of directors) and shall not adversely affect any right or protection of a director of the Corporation existing at the time of such repeal or amendment or adoption of such inconsistent provision with respect to acts or omissions occurring prior to such repeal or amendment or adoption of such inconsistent provision.

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Section 7.2 Indemnification.

(a) Each person who is or was made a party or is threatened to be made a party to or is otherwise involved in any threatened, pending or completed action, suit or proceeding, whether civil, criminal, administrative or investigative (hereinafter a “proceeding”) by reason of the fact that he or she is or was a director or officer, employee or agent of the Corporation or, while a director or officer, employee or agent of the Corporation, is or was serving at the request of the Corporation as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust or other enterprise, including service with respect to an employee benefit plan (hereinafter a “Covered Person”), whether the basis of such proceeding is alleged action in an official capacity as a director, officer, employee or agent, or in any other capacity while serving as a director, officer, employee or agent, shall be indemnified and held harmless by the Corporation to the fullest extent authorized or permitted by applicable law, as the same exists or may hereafter be amended, against all expense, liability and loss (including, without limitation, attorneys’ fees, judgments, fines, ERISA excise taxes and penalties and amounts paid in settlement) reasonably incurred or suffered by such Covered Person in connection with such proceeding, and such right to indemnification shall continue as to a person who has ceased to be a director, officer, employee or agent and shall inure to the benefit of his or her heirs, executors and administrators; provided, however, that, except for proceedings to enforce rights to indemnification, the Corporation shall indemnify a Covered Person in connection with a proceeding (or part thereof) initiated by such Covered Person only if such proceeding (or part thereof) was authorized by the Board. The right to indemnification conferred by this Section 7.2 shall be a contract right and shall include the right to be paid by the Corporation the expenses incurred in defending or otherwise participating in any such proceeding in advance of its final disposition.

(b) The rights conferred on any Covered Person by this Section 7.2 shall not be exclusive of any other rights which any Covered Person may have or hereafter acquire under law, this Certificate, the By Laws, an agreement, vote of stockholders or disinterested directors, or otherwise.

(c) Any repeal or amendment of this Section 7.2 by the stockholders of the Corporation or by changes in law, or the adoption of any other provision of this Certificate inconsistent with this Section 7.2, will, unless otherwise required by law, be prospective only (except to the extent such amendment or change in law permits the Corporation to provide broader indemnification rights on a retroactive basis than permitted prior thereto), and will not in any way diminish or adversely affect any right or protection existing at the time of such repeal or amendment or adoption of such inconsistent provision in respect of any act or omission occurring prior to such repeal or amendment or adoption of such inconsistent provision.

(d) This Section 7.2 shall not limit the right of the Corporation, to the extent and in the manner authorized or permitted by law, to indemnify and to advance expenses to persons other than Covered Persons.

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ARTICLE VIII

BUSINESS COMBINATION REQUIREMENTS; EXISTENCE

Section 8.1 General.

(a) The provisions of this Article VIII shall apply during the period commencing upon the effectiveness of this Amended and Restated Certificate and terminating upon the consummation of the Corporation’s initial Business Combination and no amendment to this Article VIII shall be effective prior to the consummation of the initial Business Combination unless approved by the affirmative vote of the holders of at least sixty-five percent (65%) of all then outstanding shares of the Common Stock.

(b) Immediately after the Offering, a certain amount of the net offering proceeds received by the Corporation in the Offering (including the proceeds of any exercise of the underwriters’ over-allotment option) and certain other amounts specified in the Corporation’s registration statement on Form S-1, as initially filed with the U.S. Securities and Exchange Commission (the “SEC”) on August 6, 2021 (the “Registration Statement”), shall be deposited in a trust account (the “Trust Account”), established for the benefit of the Public Stockholders (as defined below) pursuant to a trust agreement described in the Registration Statement. Except for the withdrawal of interest to pay franchise and income taxes, none of the funds held in the Trust Account (including the interest earned on the funds held in the Trust Account) will be released from the Trust Account until the earliest to occur of (i) the completion of the initial Business Combination, (ii) the redemption of 100% of the Offering Shares (as defined below) if the Corporation is unable to complete its initial Business Combination within 18 months from the closing of the Offering and (iii) the redemption of shares in connection with a vote seeking to amend any provisions of the Amended and Restated Certificate relating to stockholders’ rights or pre-initial Business Combination activity (as described in Section 8.7). Holders of shares of Common Stock included as part of the units sold in the Offering (the “Offering Shares”) (whether such Offering Shares were purchased in the Offering or in the secondary market following the Offering and whether or not such holders are the Sponsor or officers or directors of the Corporation, or affiliates of any of the foregoing) are referred to herein as “Public Stockholders.”

Section 8.2 Redemption Rights.

(a) Prior to the consummation of the initial Business Combination, the Corporation shall provide all holders of Offering Shares with the opportunity to have their Offering Shares redeemed upon the consummation of the initial Business Combination pursuant to, and subject to the limitations of, Section 8.2(b) and 8.2(c) (such rights of such holders to have their Offering Shares redeemed pursuant to such Sections, the “Redemption Rights”) hereof for cash equal to the applicable redemption price per share determined in accordance with Section 8.2(b) hereof (the “Redemption Price”); provided, however, that the Corporation shall not redeem Offering Shares in an amount that would cause the Corporation to have net tangible assets to be less than $5,000,001 upon consummation of the initial Business Combination and after payment of deferred underwriting commissions, or any greater net tangible asset or cash requirement which may be contained in the agreement relating to the initial Business Combination (such limitation hereinafter called the “Redemption Limitation”). Notwithstanding anything to the contrary contained in this Amended and Restated Certificate, there shall be no Redemption Rights or liquidating distributions with respect to any warrant issued pursuant to the Offering.

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(b) If the Corporation offers to redeem the Offering Shares other than in conjunction with a stockholder vote on an initial Business Combination with a proxy solicitation pursuant to Regulation 14A of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (or any successor rules or regulations) and filing proxy materials with the SEC, the Corporation shall offer to redeem the Offering Shares upon the consummation of the initial Business Combination, subject to lawfully available funds therefor, in accordance with the provisions of Section 8.2(a) hereof pursuant to a tender offer in accordance with Rule 13e-4 and Regulation 14E of the Exchange Act (or any successor rule or regulation) (such rules and regulations hereinafter called the “Tender Offer Rules”) which it shall commence prior to the consummation of the initial Business Combination and shall file tender offer documents with the SEC prior to the consummation of the initial Business Combination that contain substantially the same financial and other information about the initial Business Combination and the Redemption Rights as is required under Regulation 14A of the Exchange Act (or any successor rule or regulation) (such rules and regulations hereinafter called the “Proxy Solicitation Rules”), even if such information is not required under the Tender Offer Rules; provided, however, that if a stockholder vote is required by law to approve the proposed initial Business Combination, or the Corporation decides to submit the proposed initial Business Combination to the stockholders for their approval for business or other legal reasons, the Corporation shall offer to redeem the Offering Shares, subject to lawfully available funds therefor, in accordance with the provisions of Section 8.2(a) hereof in conjunction with a proxy solicitation pursuant to the Proxy Solicitation Rules (and not the Tender Offer Rules) at a price per share equal to the Redemption Price calculated in accordance with the following provisions of this Section 8.2(b). In the event that the Corporation offers to redeem the Offering Shares pursuant to a tender offer in accordance with the Tender Offer Rules, the Redemption Price per share of the Common Stock payable to holders of the Offering Shares tendering their Offering Shares pursuant to such tender offer shall be equal to the quotient obtained by dividing: (i) the aggregate amount on deposit in the Trust Account as of two business days prior to the consummation of the initial Business Combination, including interest not previously released to the Corporation to pay its franchise and income taxes, by (ii) the total number of then outstanding Offering Shares. If the Corporation offers to redeem the Offering Shares in conjunction with a stockholder vote on the proposed initial Business Combination pursuant to a proxy solicitation, the Redemption Price per share of the Common Stock payable to holders of the Offering Shares exercising their Redemption Rights (irrespective of whether they voted in favor or against the Business Combination) shall be equal to the quotient obtained by dividing (a) the aggregate amount on deposit in the Trust Account as of two business days prior to the consummation of the initial Business Combination, including interest not previously released to the Corporation to pay its franchise and income taxes, by (b) the total number of then outstanding Offering Shares.

(c) If the Corporation offers to redeem the Offering Shares in conjunction with a stockholder vote on an initial Business Combination pursuant to a proxy solicitation, a Public Stockholder, together with any affiliate of such stockholder or any other person with whom such stockholder is acting in concert or as a “group” (as defined under Section 13(d)(3) of the Exchange Act), shall be restricted from seeking Redemption Rights with respect to more than an aggregate of 20% of the Offering Shares without the prior consent of the Corporation.

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(d) In the event that the Corporation has not consummated an initial Business Combination within 18 months from the closing of the Offering, the Corporation shall (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten (10) business days thereafter subject to lawfully available funds therefor, redeem 100% of the Offering Shares in consideration of a per-share price, payable in cash, equal to the quotient obtained by dividing (A) the aggregate amount then on deposit in the Trust Account, including interest not previously released to the Corporation to pay its franchise and income taxes (less up to $100,000 of such net interest to pay dissolution expenses), by (B) the total number of then outstanding Offering Shares, which redemption will completely extinguish rights of the Public Stockholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the remaining stockholders and the Board in accordance with applicable law, dissolve and liquidate, subject in each case to the Corporation’s obligations under the DGCL to provide for claims of creditors and other requirements of applicable law.

(e) If the Corporation offers to redeem the Offering Shares in conjunction with a stockholder vote on an initial Business Combination, the Corporation shall consummate the proposed initial Business Combination only if (i) such initial Business Combination is approved by the affirmative vote of the holders of a majority of the shares of the Common Stock that are voted at a stockholder meeting held to consider such initial Business Combination and (ii) the Redemption Limitation is not exceeded.

(f) If the Corporation conducts a tender offer pursuant to Section 8.2(b), the Corporation shall consummate the proposed initial Business Combination only if the Redemption Limitation is not exceeded.

Section 8.3 Distributions from the Trust Account.

(a) A Public Stockholder shall be entitled to receive funds from the Trust Account only as provided in Sections 8.2(a), 8.2(b), 8.2(c) or 8.7 hereof. In no other circumstances shall a Public Stockholder have any right or interest of any kind in or to distributions from the Trust Account, and no stockholder other than a Public Stockholder shall have any interest in or to the Trust Account.

(b) Each Public Stockholder that does not exercise its Redemption Rights shall retain its interest in the Corporation and shall be deemed to have given its consent to the release of the remaining funds in the Trust Account to the Corporation, and following payment to any Public Stockholders exercising their Redemption Rights, the remaining funds in the Trust Account shall be released to the Corporation.

(c) The exercise by a Public Stockholder of the Redemption Rights shall be conditioned on such Public Stockholder following the specific procedures for redemptions set forth by the Corporation in any applicable tender offer or proxy materials sent to the Public Stockholders relating to the proposed initial Business Combination. Payment of the amounts necessary to satisfy the Redemption Rights properly exercised shall be made as promptly as practical after the consummation of the initial Business Combination.

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Section 8.4 Share Issuances. Prior to the consummation of the Corporation’s initial Business Combination, the Corporation shall not issue any additional shares of capital stock of the Corporation that would entitle the holders thereof to receive funds from the Trust Account or vote on any initial Business Combination, on any pre-Business Combination activity or on any amendment to this Article VIII.

Section 8.5 Transactions with Affiliates. In the event the Corporation enters into an initial Business Combination with a target business that is affiliated with the Sponsor, or the directors or officers of the Corporation, the Corporation, or a committee of the independent directors of the Corporation, shall obtain an opinion from an independent accounting firm or an independent investment banking firm that is a member of the Financial Industry Regulatory Authority that such Business Combination is fair to the Corporation from a financial point of view.

Section 8.6 No Transactions with Other Blank Check Companies. The Corporation shall not enter into an initial Business Combination with another blank check company or a similar company with nominal operations.

Section 8.7 Additional Redemption Rights. If, in accordance with Section 8.1(a), any amendment is made to this Amended and Restated Certificate (a) to modify the substance or timing of the Corporation’s obligation to redeem 100% of the Offering Shares if the Corporation has not consummated an initial Business Combination within 18 months from the date of the closing of the Offering or to provide for redemption in connection with an initial Business Combination, the Public Stockholders shall be provided with the opportunity to redeem their Offering Shares upon the approval of any such amendment, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest not previously released to the Corporation to pay its franchise and income taxes, divided by the number of then outstanding Offering Shares; provided, however, that any such amendment will be voided, and this Article VIII will remain unchanged, if any stockholders who wish to redeem are unable to redeem due to the Redemption Limitation.

ARTICLE IX

INSOLVENCY; SALE; LEASE OR EXCHANGE OF ASSETS

Whenever a compromise or arrangement is proposed between this Corporation and its creditors or any class of them and/or between this Corporation and its stockholders or any class of them, any court of equitable jurisdiction within the State of Delaware may, on the application in a summary way of this Corporation or of any creditor or stockholder thereof or on the application of any receiver or receivers appointed for this Corporation under Section 291 of the DGCL or on the application of trustees in dissolution or of any receiver or receivers appointed for this Corporation under Section 279 of the DGCL order a meeting of the creditors or class of creditors, and/or of the stockholders or class of stockholders of this Corporation, as the case may be, to be summoned in such manner as the said court directs.

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If a majority in number representing three fourths in value of the creditors or class of creditors, and/or of the stockholders or class of stockholders of this Corporation, as the case may be, agree to any compromise or arrangement and to any reorganization of this Corporation as a consequence of such compromise or arrangement, the said compromise or arrangement and the said reorganization shall, if sanctioned by the court to which the said application has been made, be binding on all the creditors or class of creditors, and/or on all the stockholders or class of stockholders, of this Corporation, as the case may be, and also on this Corporation.

ARTICLE X

AMENDMENT OF CERTIFICATE OF INCORPORATION

The Corporation reserves the right to amend, alter, change or repeal any provision contained in this Certificate (including any Preferred Stock Designation), in the manner now or hereafter prescribed by this Certificate and the DGCL; and except as set forth in ARTICLE VII, all rights, preferences and privileges herein conferred upon stockholders, directors or any other persons by and pursuant to this Certificate in its present form or as hereafter amended are granted subject to the right reserved in this Article.

ARTICLE XI

EXCLUSIVE FORUM FOR CERTAIN LAWSUITS

Section 11.1 Forum. Unless the Corporation consents in writing to the selection of an alternative forum, the Court of Chancery of the State of Delaware (the “Court of Chancery”) shall be the sole and exclusive forum for any stockholder (including a beneficial owner) to bring (i) any derivative action or proceeding brought on behalf of the Corporation, (ii) any action asserting a claim of breach of a fiduciary duty owed by any director, officer or other employee of the Corporation to the Corporation or the Corporation’s stockholders, (iii) any action asserting a claim against the Corporation, its directors, officers or employees arising pursuant to any provision of the DGCL or this Certificate, or (iv) any action asserting a claim against the Corporation, its directors, officers or employees governed by the internal affairs doctrine and, if brought outside of Delaware, the stockholder bringing the suit will be deemed to have consented to service of process on such stockholder’s counsel, except for, as to each of (i) through (iv) above, any claim (A) as to which the Court of Chancery determines that there is an indispensable party not subject to the jurisdiction of the Court of Chancery (and the indispensable party does not consent to the personal jurisdiction of the Court of Chancery within ten days following such determination), (B) which is vested in the exclusive jurisdiction of a court or forum other than the Court of Chancery or (C) for which the Court of Chancery does not have subject matter jurisdiction. Notwithstanding the foregoing, the provisions of this Section 11.1 will not apply to suits brought to enforce a duty or liability created by the Exchange Act or any other claim for which the federal courts have exclusive jurisdiction. Additionally, unless the Corporation consents in writing to the selection of an alternative forum, the federal courts shall be the exclusive forum for the resolution of any complaint asserting a cause of action arising under the Securities Act of 1933, as amended, against the Corporation or any of its directors, officers, other employees or agents. Any person or entity purchasing or otherwise acquiring any interest in any security of the Corporation shall be deemed to have notice of and consented to the provisions of this Section 11.1.

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Section 11.2 Consent to Jurisdiction. If any action the subject matter of which is within the scope of Section 11.1 immediately above is filed in a court other than a court located within the State of Delaware (a “Foreign Action”) in the name of any stockholder, such stockholder shall be deemed to have consented to (i) the personal jurisdiction of the state and federal courts located within the State of Delaware in connection with any action brought in any such court to enforce Section 11.1 immediately above (an “FSC Enforcement Action”) and (ii) having service of process made upon such stockholder in any such FSC Enforcement Action by service upon such stockholder’s counsel in the Foreign Action as agent for such stockholder.

Section 11.3 Severability. If any provision or provisions of this ARTICLE XI shall be held to be invalid, illegal or unenforceable as applied to any person or entity or circumstance for any reason whatsoever, then, to the fullest extent permitted by law, the validity, legality and enforceability of such provisions in any other circumstance and of the remaining provisions of this ARTICLE XI (including, without limitation, each portion of any sentence of this ARTICLE XI containing any such provision held to be invalid, illegal or unenforceable that is not itself held to be invalid, illegal or unenforceable) and the application of such provision to other persons or entities and circumstances shall not in any way be affected or impaired thereby. Any person or entity purchasing or otherwise acquiring any interest in shares of capital stock of the Corporation shall be deemed to have notice of and consented to the provisions of this ARTICLE XI.

*    *    *

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3. That this Certificate, which restates and integrates and further amends the provisions of this Corporation’s Amended and Restated Certificate of Incorporation, has been duly adopted in accordance with Sections 242 and 245 of the General Corporation Law.

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FIRST AMENDMENT

TO THE

AMENDED AND RESTATED

CERTIFICATE OF INCORPORATION

OF

ALTENERGY ACQUISITION CORP.

(Pursuant to Section 242 of the

Delaware General Corporation Law)

The undersigned, being a duly authorized officer of ALTENERGY ACQUISITION CORP. (the “Corporation”), a corporation organized and existing under the laws of the State of Delaware, does hereby certify as follows:

1. The name of the Corporation is AltEnergy Acquisition Corp.

2. The Corporation’s Certificate of Incorporation was filed in the office of the Secretary of State of the State of Delaware on February 9, 2021. An Amended and Restated Certificate of Incorporation was filed in the office of the Secretary of State of the State of Delaware on October 28, 2021 and was further updated pursuant to a Certificate of Correction filed in the office of the Secretary of State of the State of Delaware on March 20, 2023 (the “Amended and Restated Certificate of Incorporation”).

2. This First Amendment to the Amended and Restated Certificate of Incorporation amends the Amended and Restated Certificate of Incorporation.

3. This First Amendment to the Amended and Restated Certificate of Incorporation was duly adopted by the affirmative vote of the holders of at least 65% of the stock entitled to vote at a meeting of stockholders in accordance with Article VII of the Amended and Restated Charter and the provisions of Section 242 of the General Corporation Law of the State of Delaware, as amended from time to time (the “DGCL”).

4. The text of Section 8.1(b) of Article VIII is hereby amended to read in full as follows:

“(b) Immediately after the Offering, a certain amount of the net offering proceeds received by the Corporation in the Offering (including the proceeds of any exercise of the underwriters’ over-allotment option) and certain other amounts specified in the Corporation’s registration statement on Form S-1, as initially filed with the U.S. Securities and Exchange Commission (the “SEC”) on August 6, 2021 (the “Registration Statement”), shall be deposited in a trust account (the “Trust Account”), established for the benefit of the Public Stockholders (as defined below) pursuant to a trust agreement described in the Registration Statement. Except for the withdrawal of interest to pay franchise and income taxes, none of the funds held in the Trust Account (including the interest earned on the funds held in the Trust Account) will be released from the Trust Account until the earliest to occur of (i) the completion of the initial Business Combination, (ii) the redemption of 100% of the Offering Shares (as defined below) if the Corporation is unable to complete its initial Business Combination within 30 months from the closing of the Offering and (iii) the redemption of shares in connection with a vote seeking to amend any provisions of the Amended and Restated Certificate relating to stockholders’ rights or pre-initial Business Combination activity (as described in Section 8.7). Holders of shares of Common Stock included as part of the units sold in the Offering (the “Offering Shares”) (whether such Offering Shares were purchased in the Offering or in the secondary market following the Offering and whether or not such holders are the Sponsor or officers or directors of the Corporation, or affiliates of any of the foregoing) are referred to herein as “Public Stockholders.”.

5. The text of Section 8.2(d) of Article VIII is hereby amended to read in full as follows:

“(d) In the event that the Corporation has not consummated an initial Business Combination within 30 months from the closing of the Offering, the Corporation shall (i) cease all operations except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than ten (10) business days thereafter subject to lawfully available funds therefor, redeem 100% of the Offering Shares in consideration of a per-share price, payable in cash, equal to the quotient obtained by dividing (A) the aggregate amount then on deposit in the Trust Account, including interest not previously released to the Corporation to pay its franchise and income taxes (less up to $100,000 of such net interest to pay dissolution expenses), by (B) the total number of then outstanding Offering Shares, which redemption will completely extinguish rights of the Public Stockholders (including the right to receive further liquidating distributions, if any), subject to applicable law, and (iii) as promptly as reasonably possible following such redemption, subject to the approval of the remaining stockholders and the Board in accordance with applicable law, dissolve and liquidate, subject in each case to the Corporation’s obligations under the DGCL to provide for claims of creditors and other requirements of applicable law.”

6. The text of Section 8.7 of Article VIII is hereby amended to read in full as follows:

“Section 8.7 Additional Redemption Rights. If, in accordance with Section 8.1(a), any amendment is made to this Amended and Restated Certificate (a) to modify the substance or timing of the Corporation’s obligation to redeem 100% of the Offering Shares if the Corporation has not consummated an initial Business Combination within 30 months from the date of the closing of the Offering or to provide for redemption in connection with an initial Business Combination, the Public Stockholders shall be provided with the opportunity to redeem their Offering Shares upon the approval of any such amendment, at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest not previously released to the Corporation to pay its franchise and income taxes, divided by the number of then outstanding Offering Shares; provided, however, that any such amendment will be voided, and this Article VIII will remain unchanged, if any stockholders who wish to redeem are unable to redeem due to the Redemption Limitation.”

IN WITNESS WHEREOF, AltEnergy Acquisition Corp. has caused this Amendment to the Amended and Restated Certificate to be duly executed in its name and on its behalf by an authorized officer as of this 28th day of April, 2023.

EXHIBIT 31.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER

PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Russell Stidolph, certify that:

1. I have reviewed this quarterly report on Form 10-Q of AltEnergy Acquisition Corp.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:

(a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b) (Paragraph omitted pursuant to SEC Release Nos. 33-8238/34-47986 and 33-8392/49313);

(c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing equivalent functions):

(a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: May 22, 2023

EXHIBIT 31.2

CERTIFICATION OF CHIEF FINANCIAL OFFICER

PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Jonathan Darnell, certify that:

1. I have reviewed this quarterly report on Form 10-Q of AltEnergy Acquisition Corp.;

2. Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3. Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4. The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and have:

(a) Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

(b) (Paragraph omitted pursuant to SEC Release Nos. 33-8238/34-47986 and 33-8392/49313);

(c) Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

(d) Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5. The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing equivalent functions):

(a) All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

(b) Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: May 22, 2023

EXHIBIT 32.1

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report on Form 10-Q of AltEnergy Acquisition Corp. (the “Company”) for the quarter ended March 31, 2023 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Russell Stidolph, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that:

1. The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

May 22, 2023

EXHIBIT 32.2

CERTIFICATION PURSUANT TO

18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

In connection with the Quarterly Report on Form 10-Q of AltEnergy Acquisition Corp. (the “Company”) for the quarter ended March 31, 2023 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Jonathan Darnell, Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. § 1350, as adopted pursuant to § 906 of the Sarbanes-Oxley Act of 2002, that:

1. The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2. The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

May 22, 2023