Exhibit
10.8


 


ESGEN
Acquisition Corporation

5956 Sherry Lane


Suite 1400


Dallas, TX 75225


September [●], 2021


 


 


 


Salient Partners, L.P.


4265 San Felipe 8th Floor


Houston, TX 77027


 


RE:          Securities
Subscription Agreement


 


Gentlemen:


 


This agreement (this “Agreement”)
is entered into on September [●], 2021 by and between certain client accounts of Salient Partners, L.P., (each, a “Subscriber”
or “you”), and ESGEN Acquisition Corporation, a Cayman Islands exempted company (the “Company”).
Pursuant to the terms hereof, the Company hereby accepts the offer of the Subscribers to purchase an aggregate amount of 831,393 Class
B ordinary shares (the “Shares”) in the individual purchase amounts indicated on the signature pages hereto. Up to
29,575 of such Shares, in the aggregate, are subject to surrender and cancellation by you, in the individual amounts indicated on the
signature pages hereto, if the underwriters of the initial public offering (“IPO”) of units (“Units”)
of the Company do not fully exercise their over-allotment option (the “Over-allotment Option”). The Company and each
Subscriber’s agreements regarding such Shares are as follows:


 


1.             Purchase of Securities


 


1.1              
Purchase of Shares


 


For the sum of $0.35 per share
(the “Purchase Price”), which the Company acknowledges receiving in cash, the Company hereby issues the Shares to the
Subscribers, and the Subscribers hereby subscribe for and purchases the Shares from the Company, 29,575 of which are subject to surrender
and cancellation in the aggregate, on the terms and subject to the conditions set forth in this Agreement. All references in this Agreement
to shares of the Company being surrendered and canceled shall take effect as surrenders and cancellations for no consideration of such
shares as a matter of Cayman Islands law.


 


2.             Representations, Warranties and Agreements


 


2.1              
Subscriber’s Representations, Warranties and Agreements


 


To induce the Company to issue
the Shares to each Subscriber, each Subscriber hereby represents and warrants to the Company and agrees with the Company as follows:


 


2.1.1         
No Government Recommendation or Approval


 


The Subscriber understands that
no federal or state agency has passed upon or made any recommendation or endorsement of the offering of the Shares.


 






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2.1.2         
No Conflicts


 


The execution, delivery and
performance of this Agreement and the consummation by the Subscriber of the transactions contemplated hereby do not violate, conflict
with or constitute a default under (i) the formation and governing documents of the Subscriber, (ii) any agreement, indenture or instrument
to which the Subscriber is a party or (iii) any law, statute, rule or regulation to which the Subscriber is subject, or any agreement,
order, judgment or decree to which the Subscriber is subject.


 


2.1.3         
Registration and Authority


 


The Subscriber possesses all
requisite power and authority necessary to carry out the transactions contemplated by this Agreement. Upon execution and delivery by you,
this Agreement will be a legal, valid and binding agreement of Subscriber, enforceable against Subscriber in accordance with its terms,
except as such enforceability may be limited by applicable bankruptcy, insolvency, fraudulent conveyance or similar laws affecting the
enforcement of creditors’ rights generally and subject to general principles of equity (regardless of whether enforcement is sought
in a proceeding at law or in equity).


 


2.1.4         
Experience, Financial Capability and Suitability


 


Subscriber is: (i) sophisticated
in financial matters and is able to evaluate the risks and benefits of the investment in the Shares; and (ii) able to bear the economic
risk of its investment in the Shares for an indefinite period of time because the Shares have not been registered under the Securities
Act (as defined below) and therefore cannot be sold unless subsequently registered under the Securities Act or an exemption from such
registration is available. Subscriber is capable of evaluating the merits and risks of its investment in the Company and has the capacity
to protect its own interests. Subscriber must bear the economic risk of this investment until the Shares are sold pursuant to: (i) an
effective registration statement under the Securities Act; or (ii) an exemption from registration available with respect to such sale.
Subscriber is able to bear the economic risks of an investment in the Shares and to afford a complete loss of Subscriber’s investment
in the Shares.


 


2.1.5         
Access to Information; Independent Investigation


 


Prior to the execution of this
Agreement, the Subscriber has had the opportunity to ask questions of and receive answers from representatives of the Company concerning
an investment in the Company, as well as the finances, operations, business and prospects of the Company, and the opportunity to obtain
additional information to verify the accuracy of all information so obtained. In determining whether to make this investment, Subscriber
has relied solely on Subscriber’s own knowledge and understanding of the Company and its business based upon Subscriber’s
own due diligence investigation and the information furnished pursuant to this paragraph. Subscriber understands that no person has been
authorized to give any information or to make any representations which were not furnished pursuant to this Section 2 and Subscriber has
not relied on any other representations or information in making its investment decision, whether written or oral, relating to the Company,
its operations and/or its prospects.


 


2.1.6         
Regulation D Offering


 


Subscriber represents that it
is an “accredited investor” as such term is defined in Rule 501(a) of Regulation D under the Securities Act of 1933, as amended
(the “Securities Act”) and acknowledges the sale contemplated hereby is being made in reliance on a private placement
exemption to “accredited investors” within the meaning of Section 501(a) of Regulation D under the Securities Act or similar
exemptions under federal and state law.


 






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2.1.7         
Investment Purposes


 


The Subscriber is purchasing
the Shares solely for investment purposes, for the Subscriber’s own account and not for the account or benefit of any other person,
and not with a view towards the distribution or dissemination thereof. The Subscriber did not decide to enter into this Agreement as a
result of any general solicitation or general advertising within the meaning of Rule 502 of Regulation D under the Securities Act.


 


2.1.8         
Restrictions on Transfer; Shell Company


 


Subscriber understands the Shares
are being offered in a transaction not involving a public offering within the meaning of the Securities Act. Subscriber understands the
Shares will be “restricted securities” within the meaning of Rule 144(a)(3) under the Securities Act, and Subscriber understands
that the certificates representing the Shares will contain a legend in respect of such restrictions. If in the future the Subscriber decides
to offer, resell, pledge or otherwise transfer the Shares, such Shares may be offered, resold, pledged or otherwise transferred only pursuant
to: (i) registration under the Securities Act; or (ii) an available exemption from registration. Subscriber agrees that if any transfer
of its Shares or any interest therein is proposed to be made, as a condition precedent to any such transfer, Subscriber may be required
to deliver to the Company an opinion of counsel satisfactory to the Company. Absent registration or an exemption, the Subscriber agrees
not to resell the Shares. Subscriber further acknowledges that because the Company is a shell company, Rule 144 may not be available to
the Subscriber for the resale of the Shares until one year following consummation of the initial business combination of the Company,
despite technical compliance with the requirements of Rule 144 and the release or waiver of any contractual transfer restrictions.


 


2.1.9         
No Governmental Consents


 


No governmental, administrative
or other third party consents or approvals are required or necessary on the part of Subscriber in connection with the transactions contemplated
by this Agreement.


 


2.2              
Company’s Representations, Warranties and Agreements


 


To induce each Subscriber
to purchase the Shares, the Company hereby represents and warrants to each Subscriber and agrees with each Subscriber as follows:


 


2.2.1         
Incorporation and Corporate Power


 


The Company is a Cayman Islands
exempted company and is qualified to do business in every jurisdiction in which the failure to so qualify would reasonably be expected
to have a material adverse effect on the financial condition, operating results or assets of the Company. The Company possesses all requisite
corporate power and authority necessary to carry out the transactions contemplated by this Agreement. Upon execution and delivery by the
Company, this Agreement will be a legal, valid and binding agreement of the Company, enforceable against the Company in accordance with
its terms, except as such enforceability may be limited by applicable bankruptcy, insolvency, fraudulent conveyance or similar laws affecting
the enforcement of creditors’ rights generally and subject to general principles of equity (regardless of whether enforcement is
sought in a proceeding at law or in equity).


 


2.2.2         
No Conflicts


 


The execution, delivery
and performance of this Agreement and the consummation by the Company of the transactions contemplated hereby do not violate,
conflict with or constitute a default under (i) the memorandum and articles of association of the Company, (ii) any agreement,
indenture or instrument to which the Company is a party or (iii) any law, statute, rule or regulation to which the Company is
subject, or any agreement, order, judgment or decree to which the Company is subject.


 






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2.2.3         
Title to Securities


 


Upon issuance in accordance
with, and payment pursuant to, the terms hereof, and registration in the Company’s register of members, the Shares will be duly
and validly issued, fully paid and nonassessable. Upon issuance in accordance with, and payment pursuant to, the terms hereof, and registration
in the Company’s register of members, each Subscriber will have or receive good title to the Shares, free and clear of all liens,
claims and encumbrances of any kind, other than (i) transfer restrictions hereunder and other agreements to which the Shares may be subject,
(ii) transfer restrictions under federal and state securities laws, and (iii) liens, claims or encumbrances imposed due to the actions
of each Subscriber.


 


2.2.4         
No Adverse Actions


 


There are no actions, suits,
investigations or proceedings pending, threatened against or affecting the Company which: (i) seek to restrain, enjoin, prevent the consummation
of or otherwise affect the transactions contemplated by this Agreement; or (ii) question the validity or legality of any transactions
or seeks to recover damages or to obtain other relief in connection with any transactions.


 


2.2.5         
Change in Investment.


 


If,
prior to, or in connection with, the Company’s initial business combination, the Company’s sponsor or members of management
of the Company who directly or indirectly hold Shares and/or private placement warrants agree to forfeit, transfer, exchange, defer, escrow,
make contingent, subject to earnout or vesting, lockup or amend the terms of all or any portion of the Shares, private placement warrants
and/or the Company’s Class A ordinary shares, par value $0.0001 per share (the “Class A Ordinary Shares”)
issuable upon conversion of the Shares or exercise of the private placement warrants (collectively, the “Insider Securities”)
or any rights or agreements relating thereto (including any lockup agreement, insider letter or registration rights agreement entered
into with respect to such securities) or to enter into any other arrangements (including agreements relating to lockup, forfeiture, earnout,
escrow and vesting provisions) with respect to the any of the Insider Securities to facilitate the consummation of an initial business
combination, including voting in favor of any amendment to the terms of the any such Insider Securities (each, a “Change in Investment”),
each Subscriber (and any transferees or successors) shall be bound by such terms and shall enter into any such agreement or arrangement
involving a Change in Investment (including any amendment to this Agreement), vote in favor of any proposal involving a Change in Investment
and otherwise facilitate or take any action to effect or permit any Change in Investment with respect to the Shares, warrants and/or shares
of Class A Ordinary Shares issuable upon exercise of the warrants on the same terms and conditions and on a pro rata basis as the Company’s
sponsor and members of management of the Company (and/or their affiliates) which hold such shares of such affected Insider Securities.


 


3.             Surrender and Cancellation of Shares


 


3.1              
Partial or No Exercise of the Over-allotment Option


 


In the event the
Over-allotment Option granted to the representative(s) of the underwriters of the Company’s IPO is not exercised in full, each
Subscriber acknowledges and agrees that it shall surrender for cancellation any and all rights to such number of Shares (up to an
aggregate of 29,575 Shares and pro rata based upon the percentage of the Over-allotment Option exercised, in the individual amounts
indicated on the signature pages hereto) such that immediately following such surrender, the Subscribers (and all other initial
shareholders prior to the IPO, if any) will own an aggregate number of Shares (not including ordinary shares issuable upon exercise
of any warrants or any ordinary shares purchased by the Subscribers in the Company’s IPO or in the aftermarket), which, when
combined with the shares of our sponsor and independent directors, equal to 20% of the issued and outstanding ordinary shares of the
Company immediately following the IPO.


 






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3.2              
Termination of Rights as Shareholder


 


If any of the Shares are surrendered
and cancelled in accordance with this Section 3, then after such time each Subscriber (or successor in interest), shall no longer have
any rights as a holder of such Shares, and the Company shall take such action as is appropriate to cancel such Shares.


 


4.            
Waiver of Liquidation Distributions; Redemption Rights


 


In connection with the Shares
purchased pursuant to this Agreement, each Subscriber hereby waives any and all right, title, interest or claim of any kind in or to any
distributions by the Company from the trust account which will be established for the benefit of the Company’s public shareholders
and into which substantially all of the proceeds of the IPO will be deposited (the “Trust Account”), in the event of
a liquidation of the Company upon the Company’s failure to timely complete an initial business combination. For purposes of clarity,
in the event any Subscriber purchases ordinary shares in the IPO or in the aftermarket, any additional Shares so purchased shall be eligible
to receive any liquidating distributions by the Company. However, in no event will any Subscriber have the right to redeem any ordinary
shares into funds held in the Trust Account upon the successful completion of an initial business combination.


 


5.             Restrictions
on Transfer


 


5.1              
Securities Law Restrictions


 


In addition to any restrictions
to be contained in that certain letter agreement (commonly known as an “Insider Letter”) to be dated as of the closing
of the IPO by and between each Subscriber and the Company, each Subscriber agrees not to sell, transfer, pledge, hypothecate or otherwise
dispose of all or any part of the Shares unless, prior thereto (i) a registration statement on the appropriate form under the Securities
Act and applicable state securities laws with respect to the Shares proposed to be transferred shall then be effective or (ii) the Company
has received an opinion from counsel reasonably satisfactory to the Company, that such registration is not required because such transaction
is exempt from registration under the Securities Act and the rules promulgated by the Securities and Exchange Commission thereunder and
with all applicable state securities laws.


 


5.2              
Restrictive Legends


 


Any certificates representing
the Shares shall have endorsed thereon legends substantially as follows:


 


“THE SECURITIES REPRESENTED HEREBY
HAVE NOT BEEN REGISTERED UNDER THE UNITED STATES SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS AND NEITHER THE
SECURITIES NOR ANY INTEREST THEREIN MAY BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN
EFFECTIVE REGISTRATION STATEMENT UNDER SUCH ACT OR SUCH LAWS OR AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT AND SUCH LAWS WHICH,
IN THE OPINION OF COUNSEL, IS AVAILABLE.”


 


“THE SECURITIES REPRESENTED BY THIS CERTIFICATE
ARE SUBJECT TO LOCKUP PROVISIONS AND MAY NOT BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED DURING THE TERM OF THE LOCKUP.”


 






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5.3              
Additional Shares or Substituted Securities


 


In the event of the declaration
of a share capitalization, the declaration of an extraordinary dividend payable in a form other than Shares, a spin-off, a share sub-division,
an adjustment in conversion ratio, a recapitalization or a similar transaction affecting the Company’s outstanding Shares without
receipt of consideration, any new, substituted or additional securities or other property which are by reason of such transaction distributed
with respect to any Shares subject to this Section 5 or into which such Shares thereby become convertible shall immediately be subject
to Section 3 or this Section 5. Appropriate adjustments to reflect the distribution of such securities or property shall be made to the
number and/or class of Shares subject to Section 3 or this Section 5.


 


5.4              
Registration Rights


 


Each Subscriber acknowledges
that the Shares are being purchased pursuant to an exemption from the registration requirements of the Securities Act and will become
freely tradable only after certain conditions are met or they are registered pursuant to a Registration and Shareholder Rights Agreement
to be entered into with the Company prior to the closing of the IPO.


 


6.             Other Agreements


 


6.1              
Further Assurances


 


Each Subscriber agrees to
execute such further instruments and to take such further action as may reasonably be necessary to carry out the intent of this Agreement.


 


6.2              
Notices


 


All notices, statements or
other documents which are required or contemplated by this Agreement shall be: (i) in writing and delivered personally or sent by first
class registered or certified mail, overnight courier service or facsimile or electronic transmission to the address designated in writing;
(ii) by facsimile to the number most recently provided to such party or such other address or fax number as may be designated in writing
by such party; and (iii) by electronic mail, to the electronic mail address most recently provided to such party or such other electronic
mail address as may be designated in writing by such party. Any notice or other communication so transmitted shall be deemed to have been
given on the day of delivery, if delivered personally, on the business day following receipt of written confirmation, if sent by facsimile
or electronic transmission, one (1) business day after delivery to an overnight courier service or five (5) days after mailing if sent
by mail.


 


6.3              
Entire Agreement


 


. This Agreement,
together with that certain Insider Letter to be entered into between each Subscriber and the Company, substantially in the form to
be filed as an exhibit to the Registration Statement on Form S-1 associated with the Company’s IPO, embodies the entire
agreement and understanding between the Subscriber and the Company with respect to the subject matter hereof and supersedes all
prior oral or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty,
covenant or agreement of any kind not expressly set forth in this Agreement shall affect, or be used to interpret, change or
restrict, the express terms and provisions of this Agreement.


 






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6.4              
Modifications and Amendments


 


The terms and provisions of
this Agreement may be modified or amended only by written agreement executed by all parties hereto.


 


6.5              
Waivers and Consents


 


The terms and provisions of
this Agreement may be waived, or consent for the departure therefrom granted, only by a written document executed by the party entitled
to the benefits of such terms or provisions. No such waiver or consent shall be deemed to be or shall constitute a waiver or consent with
respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver or consent shall be effective only
in the specific instance and for the purpose for which it was given, and shall not constitute a continuing waiver or consent.


 


6.6              
Assignment


 


The rights and obligations
under this Agreement may not be assigned by either party hereto without the prior written consent of the other party.


 


6.7              
Benefit


 


All statements, representations,
warranties, covenants and agreements in this Agreement shall be binding on the parties hereto and shall inure to the benefit of the respective
successors and permitted assigns of each party hereto. Nothing in this Agreement shall be construed to create any rights or obligations
except among the parties hereto, and no person or entity shall be regarded as a third-party beneficiary of this Agreement.


 


6.8              
Governing Law


 


This Agreement and the rights
and obligations of the parties hereunder shall be construed in accordance with and governed by the laws of Delaware applicable to contracts
wholly performed within the borders of such state, without giving effect to the conflict of law principles thereof.


 


6.9              
Severability


 


In the event that any court
of competent jurisdiction shall determine that any provision, or any portion thereof, contained in this Agreement shall be unreasonable
or unenforceable in any respect, then such provision shall be deemed limited to the extent that such court deems it reasonable and enforceable,
and as so limited shall remain in full force and effect. In the event that such court shall deem any such provision, or portion thereof,
wholly unenforceable, the remaining provisions of this Agreement shall nevertheless remain in full force and effect.


 


6.10           
No Waiver of Rights, Powers and Remedies


 


No failure or delay by a
party hereto in exercising any right, power or remedy under this Agreement, and no course of dealing between the parties hereto,
shall operate as a waiver of any such right, power or remedy of such party. No single or partial exercise of any right, power or
remedy under this Agreement by a party hereto, nor any abandonment or discontinuance of steps to enforce any such right, power or
remedy, shall preclude such party from any other or further exercise thereof or the exercise of any other right, power or remedy
hereunder. The election of any remedy by a party hereto shall not constitute a waiver of the right of such party to pursue other
available remedies. No notice to or demand on a party not expressly required under this Agreement shall entitle the party receiving
such notice or demand to any other or further notice or demand in similar or other circumstances or constitute a waiver of the
rights of the party giving such notice or demand to any other or further action in any circumstances without such notice or
demand.


 






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6.11           
Survival of Representations and Warranties


 


All representations and warranties
made by the parties hereto in this Agreement or in any other agreement, certificate or instrument provided for or contemplated hereby,
shall survive the execution and delivery hereof and any investigations made by or on behalf of the parties.


 


6.12           
No Broker or Finder


 


Each of the parties hereto
represents and warrants to the other that no broker, finder or other financial consultant has acted on its behalf in connection with this
Agreement or the transactions contemplated hereby in such a way as to create any liability on the other. Each of the parties hereto agrees
to indemnify and save the other harmless from any claim or demand for commission or other compensation by any broker, finder, financial
consultant or similar agent claiming to have been employed by or on behalf of such party and to bear the cost of legal expenses incurred
in defending against any such claim.


 


6.13           
Headings and Captions


 


The headings and captions
of the various subdivisions of this Agreement are for convenience of reference only and shall in no way modify or affect the meaning or
construction of any of the terms or provisions hereof.


 


6.14           
Counterparts


 


This Agreement may be executed
in one or more counterparts, all of which when taken together shall be considered one and the same agreement and shall become effective
when counterparts have been signed by each party and delivered to the other party, it being understood that both parties need not sign
the same counterpart. In the event that any signature is delivered by facsimile transmission or any other form of electronic delivery,
such signature shall create a valid and binding obligation of the party executing (or on whose behalf such signature is executed) with
the same force and effect as if such signature page were an original thereof.


 


6.15           
Construction


 


The parties hereto have
participated jointly in the negotiation and drafting of this Agreement. If an ambiguity or question of intent or interpretation
arises, this Agreement will be construed as if drafted jointly by the parties hereto and no presumption or burden of proof will
arise favoring or disfavoring any party hereto because of the authorship of any provision of this Agreement. The words
 “include,” “includes,” and “including” will be deemed to be followed by
 “without limitation.” Pronouns in masculine, feminine, and neuter genders will be construed to include any other
gender, and words in the singular form will be construed to include the plural and vice versa, unless the context otherwise
requires. The words “this Agreement,” “herein,” “hereof,”
 “hereby,” “hereunder,” and words of similar import refer to this Agreement as a whole and not
to any particular subdivision unless expressly so limited. The parties hereto intend that each representation, warranty, and
covenant contained herein will have independent significance. If any party hereto has breached any representation, warranty, or
covenant contained herein in any respect, the fact that there exists another representation, warranty or covenant relating to the
same subject matter (regardless of the relative levels of specificity) which such party hereto has not breached will not detract
from or mitigate the fact that such party hereto is in breach of the first representation, warranty, or covenant.


 






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6.16           
Mutual Drafting


 


This Agreement is the joint
product of the Subscriber and the Company and each provision hereof has been subject to the mutual consultation, negotiation and agreement
of such parties and shall not be construed for or against any party hereto.


 


7.             Voting and Redemption of Shares


 


Each Subscriber agrees to vote the Shares in favor
of an initial business combination that the Company negotiates and submits for approval to the Company’s shareholders and shall
not seek redemption or repurchase with respect to such Shares. Additionally, each Subscriber agrees not to tender any Shares in connection
with a tender offer presented to the Company’s shareholders in connection with an initial business combination negotiated by the
Company.


 


[Signature Page Follows]


 






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If the foregoing accurately
sets forth our understanding and agreement, please sign the enclosed copy of this Agreement and return it to us.


 


 


	 	Very truly yours,
	 	 
	 	ESGEN ACQUISITION CORPORATION
	 	 
	 	By:	 
	 	Name:	James P. Benson
	 	Title:	Authorized Signatory




 


Accepted and agreed as of the date first written
above.


 


	[SIGNATORY]	 
	 	 
	By:	 	 
	Name:	[●]	 
	Title:	[●]