Exhibit 10.8


 


TortoiseEcofin
Acquisition Corp. III


5100 W. 115th Place


Leawood, KS 66211


 


[●], 2021


 


Tortoise Capital Advisors, L.L.C.


5100 W. 115th Place


Leawood, KS 66211


 


Re: Administrative Services
Agreement


 


Ladies and Gentlemen:


 


This letter agreement
by and between TortoiseEcofin Acquisition Corp. III (the “Company”) and Tortoise Capital Advisors, L.L.C.
(“Tortoise Capital Advisors”), dated as of the date hereof, will confirm our agreement that, commencing
on the date the securities of the Company are first listed on the New York Stock Exchange (the “Listing Date”),
pursuant to a Registration Statement on Form S-1 and prospectus filed with the Securities and Exchange Commission (the “Registration
Statement”) and continuing until the earlier of the consummation by the Company of an initial business combination
and the Company’s liquidation (in each case as described in the Registration Statement) (such earlier date hereinafter referred
to as the “Termination Date”):


 


(i) Tortoise
Capital Advisors shall make available to the Company, at 5100 W. 115th Place, Leawood, KS 66211 (or any successor location
of Tortoise Capital Advisors), certain office space, utilities, secretarial support and administrative services as may be reasonably
required by the Company. In exchange therefor, the Company shall pay Tortoise Capital Advisors the sum of $10,000 per month on
the Listing Date and continuing monthly thereafter until the Termination Date; provided, however, if the Listing Date occurs on
a day other than the first day of the month, the first payment due under this letter agreement shall be pro-rated based on a 30
day month; and


 


(ii) Tortoise
Capital Advisors hereby irrevocably waives any and all right, title, interest, causes of action and claims of any kind (each, a
“Claim”) in or to, and any and all right to seek payment of any amounts due to it out of, the trust account
established for the benefit of the public shareholders of the Company and into which substantially all of the proceeds of the Company’s
initial public offering will be deposited (the “Trust Account”), and hereby irrevocably waives any Claim
it may have in the future as a result of, or arising out of, this letter agreement, which Claim would reduce, encumber or otherwise
adversely affect the Trust Account or any monies or other assets in the Trust Account, and further agrees not to seek recourse,
reimbursement, payment or satisfaction of any Claim against the Trust Account or any monies or other assets in the Trust Account
for any reason whatsoever.


 


This letter agreement
constitutes the entire agreement and understanding of the parties hereto in respect of its subject matter and supersedes all prior
understandings, agreements or representations by or among the parties hereto, written or oral, to the extent they relate in any
way to the subject matter hereof or the transactions contemplated hereby.


 


This letter agreement
may not be amended, modified or waived as to any particular provision, except by a written instrument executed by the parties hereto.


 


No party hereto may
assign either this letter agreement or any of its rights, interests or obligations hereunder without the prior written approval
of the other party. Any purported assignment in violation of this paragraph shall be void and ineffectual and shall not operate
to transfer or assign any interest or title to the purported assignee.


 


This letter agreement,
the entire relationship of the parties hereto, and any litigation between the parties (whether grounded in contract, tort, statute,
law or equity) shall be governed by, construed in accordance with, and interpreted pursuant to the laws of the State of New York,
without giving effect to its choice of laws principles.


 


[signature page follows]


 




     


     


    

 


	 	Very truly yours,
	 	 
	 	TortoiseEcofin Acquisition Corp. III
	 	 
	 	By:	                             
	 	Name: 	Vincent T. Cubbage
	 	Title:	Chief Executive Officer


 


	AGREED TO AND ACCEPTED BY:	 
	 	 
	TORTOISE CAPITAL ADVISORS, L.L.C.	 
	 	 	 
	By:	                      	 
	Name: 	Michelle Johnston	 
	Title:	Authorized Signer	 


 


 


[Signature Page to Administrative Services
Agreement]