United States securities and exchange commission logo

                              March 3, 2021

       John F. Erhard
       Chief Executive Officer
       ArcLight Clean Transition Corp. II
       200 Clarendon Street, 55th Floor
       Boston, Massachusetts 02116

                                                        Re: ArcLight Clean
Transition Corp. II
Statement on Form S-1
                                                            Filed February 4,
                                                            File No. 333-252730

       Dear Mr. Erhard :

              We have reviewed your registration statement and have the
following comments. In
       some of our comments, we may ask you to provide us with information so
we may better
       understand your disclosure.

              Please respond to this letter by amending your registration
statement and providing the
       requested information. If you do not believe our comments apply to your
facts and
       circumstances or do not believe an amendment is appropriate, please tell
us why in your

              After reviewing any amendment to your registration statement and
the information you
       provide in response to these comments, we may have additional comments.

       Registration Statement on Form S-1 filed February 4, 2021


   1.                                                   We note that the
calculation of registration fee table includes the Class A ordinary shares
                                                        underlying redeemable
warrants included in the units. However, the risk factor on page
                                                        49 indicates you are
not registering the Class A ordinary shares issuable upon exercise of
                                                        the warrants. Please
reconcile or advise.
       Risk Factors, page 35

   2.                                                   Given the length of
this section, please revise to comply with Item 105 of Regulation
                                                        S-K so that the risk
factors are organized logically with relevant headings.
 John F. Erhard
FirstName  LastNameJohn
                Transition F. Erhard
ArcLight Clean             Corp. II
March      NameArcLight Clean Transition Corp. II
       3, 2021
March2 3, 2021 Page 2
FirstName LastName
Capitalization, page 81

3.       Please revise the amount disclosed for As Adjusted Class A ordinary
shares subject to
         possible redemption to reflect the dollar value of the shares rather
than the number of
         shares outstanding.
        We remind you that the company and its management are responsible for
the accuracy
and adequacy of their disclosures, notwithstanding any review, comments, action
or absence of
action by the staff.

       Refer to Rules 460 and 461 regarding requests for acceleration. Please
allow adequate
time for us to review any amendment prior to the requested effective date of
the registration

        You may contact Babette Cooper at 202-551-3396 or Kristina Marrone at
if you have questions regarding comments on the financial statements and
related matters. Please
contact Ronald (Ron) E. Alper at 202-551-3329 or Maryse Mills-Apenteng at
202-551-3457 with
any other questions.


                                                              Division of
Corporation Finance
                                                              Office of Real
Estate & Construction
cc:      James S. Rowe