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Exhibit 10.10a

October 12, 2012

SolarCity Corporation

3055 Clearview Way

San Mateo, CA 94127

Ladies and Gentlemen:

Reference is made to that certain Credit Agreement dated as of September 10, 2012 (the “Revolving Credit Agreement”) among SolarCity Corporation, a Delaware corporation (“Borrower”), the guarantors thereunder, the Lenders thereunder (“Revolving Lenders”), Bank of America, N.A., as administrative agent (in such capacity, “Revolving Facility Agent”), and Merrill Lynch, Pierce, Fenner & Smith Incorporated, as sole lead arranger and sole book manager.

Pursuant to Section 6.18(e) of the Revolving Credit Agreement, Borrower is required to provide evidence the UCC financing statement recorded with the Delaware Secretary of State on March 19, 2009 with the filing number 90892031, naming Duvera Billing Services, LLC as the secured party thereunder and Borrower as the debtor thereunder (the “Duvera Lien”), has been properly terminated within 60 days of the Closing Date. Borrower informed Revolving Facility Agent and the Revolving Lenders that in connection with the Duvera Lien, certain obligations relating to performance based incentives by the California Solar Initiative Program remain outstanding and are secured by the Duvera Lien. Accordingly, Borrower has requested Section 6.18(e) of the Revolving Credit Agreement be deleted in its entirety.

Pursuant to Section 5.21(g) of the Revolving Credit Agreement, Borrower is required to list each location where any personal property Collateral is located at any premises owned or leased by a Loan Party with a Collateral value in excess of $1,000,000. Borrower identified, in part (D) of Schedule 5.21(g)(ii), the Cranbury Township warehouse as containing inventory in excess of $1,000,000 but subsequent to the Closing Date determined such warehouse contains inventory below such threshold. Borrower also informed the Revolving Lenders of additional corrections to Schedule 5.21(g)(ii). Accordingly, Borrower has requested that Schedule 5.21(g)(ii) of the Revolving Credit Agreement be deleted in its entirety and replaced with the Schedule 5.21(g)(ii) attached hereto.

Revolving Facility Agent and Revolving Lenders (by their acceptance and agreement below) hereby (i) consent and authorize the deletion of Section 6.18(e) of the Revolving Credit Agreement in its entirety; and (ii) consent and authorize the deletion of Schedule 5.21(g)(ii) of the Revolving Credit Agreement in its entirety and replacement with Schedule 5.21(g)(ii) attached hereto.

The consents set forth above shall be effective only in this specific instance and for the specific purpose for which it is given, and this consent shall not entitle Borrower to any other or further

consent or waiver in any similar or other circumstances. The consent set forth above shall be limited precisely as written and shall not be deemed to (a) be a waiver or modification of any other term or condition of the Revolving Credit Agreement or any other Loan Document (as defined in the Revolving Credit Agreement) or (b) prejudice any right or remedy which Revolving Facility Agent or Revolving Lenders may now have or may have in the future under or in connection with the Revolving Credit Agreement or any Loan Document (as defined in the Revolving Credit Agreement).

This letter agreement may be executed in any number of counterparts and by different parties hereto in separate counterparts, each of which when so executed and delivered shall be an original, but all of which shall together constitute one and the same instrument. Delivery of an executed counterpart of this letter agreement by telefacsimile or other electronic transmission shall be equally as effective as delivery of an original executed counterpart of this letter agreement. Any party delivering an executed counterpart of this letter agreement by telefacsimile or other electronic transmission shall also deliver an original executed counterpart of this letter agreement, but the failure to do so shall not affect the validity, enforceability or binding effect of this letter agreement.

Please acknowledge your receipt of this letter agreement and acceptance of the foregoing terms and conditions by signing and dating the enclosed counterpart of this letter agreement where indicated below and returning the same to the undersigned as soon as possible.

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If the foregoing is in accordance with your understanding, please sign and return this letter agreement to us.

Consent Letter - Revolving Credit Agreement

Consent Letter - Revolving Credit Agreement

Consent Letter - Revolving Credit Agreement

Consent Letter - Revolving Credit Agreement

Consent Letter - Revolving Credit Agreement

SCHEDULE 5.21(g)(ii)

Other Properties

(A)

(B)

(C)

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-3-

-4-

(D)²

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