AMENDED AND RESTATED INTERIM AGREEMENT

Exhibit 10.2

AMENDED AND RESTATED INTERIM AGREEMENT

This Amended and Restated Interim Agreement (this “Agreement”) is made as of December 9, 2015, by and among SunEdison, Inc., a Delaware corporation (“Parent”), SEV Merger Sub Inc., a Delaware corporation and a wholly-owned subsidiary of Parent (“Merger Sub”), and TerraForm Power, LLC, a Delaware limited liability company (“TERP”) (each, a “Party” and collectively, the “Parties”). Capitalized terms used but not defined herein shall have the respective meanings given to them in the Merger Agreement (as defined below) unless otherwise specified in this Agreement.

RECITALS

1. On July 20, 2015, Parent and Merger Sub entered into an Agreement and Plan of Merger (as amended, restated, amended and restated, supplemented or otherwise modified, the “Merger Agreement”), by and among Parent, Merger Sub and Vivint Solar, Inc., a Delaware corporation (the “Company”), pursuant to which Merger Sub will be merged with and into the Company (the “Merger”), with the Company becoming the surviving entity and a wholly-owned subsidiary of Parent.

2. On the date hereof, TERP and Parent have executed an Amended and Restated Purchase Agreement (as amended, restated, amended and restated, supplemented or otherwise modified, the “Purchase Agreement”), pursuant to which TERP has agreed to pay the Purchase Price (as defined in the Purchase Agreement) to Parent in consideration for the acquisition of certain subsidiaries of the Company.

3. Pursuant to the terms of the Purchase Agreement, Parent and TERP have agreed that immediately following the Effective Time under the Merger Agreement (the “Closing”), Parent will cause the Company to transfer to TERP the assets and interests identified on Exhibit A of the Purchase Agreement that will be owned by the Company at Closing (the “Carveout Assets”, and such transaction, the “Carveout Transaction”), subject to the terms and conditions set forth in the Purchase Agreement.

4. On or about the date hereof, TERP and Parent have executed a consent agreement (the “Consent”), pursuant to which TERP has consented to certain amendments to the Merger Agreement and the grant by Parent of certain waivers and consents under the Merger Agreement, all as set forth in the Consent.

5. On July 19, 2015 the Parties entered into an Interim Agreement (the “Original IA”) memorializing certain agreements among the Parties related to the Merger Agreement and the Purchase Agreement and the Parties desire to amend and restate the Original IA in its entirety.

Therefore, the Parties hereby agree as follows:

1.1. Pre-Closing Decisions. TERP agrees that, notwithstanding the pending Carveout Transaction or any provision of the Purchase Agreement, all decisions to be made under and in connection with the Merger Agreement, and the transactions contemplated thereby, shall be made in agreement by both Parent and TERP, each acting in its reasonable discretion; provided, however, that all determinations to be made under and in connection with the Merger Agreement that pertain to the Carveout Assets shall be made by TERP acting in its sole discretion (provided that if any such determination requires a consent to be granted by Parent under the Merger Agreement, TERP shall not unreasonably withhold, condition or delay its consent if Parent is unable to unreasonably withhold, condition or delay its consent under the Merger Agreement and which consent by TERP shall be deemed to be granted five (5) Business Days after written request for such consent has been delivered to TERP by Parent unless TERP shall have denied such consent request in writing).

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1.2. Termination Fee. Any Termination Fee paid by the Company or any of its affiliates pursuant to the Merger Agreement or otherwise shall be split between each of Parent and TERP in accordance with their respective Pro Rata Share (as defined in Section 1.4 below). Promptly (and, in any event, within two (2) Business Days) after its receipt of the Termination Fee, Parent shall pay, or cause to be paid, to TERP its Pro Rata Share.

1.3. Certain Obligations.

1.3.1. Other than with respect to the indemnification obligations of TERP set forth in Section 1.3.2 below, Parent hereby agrees to indemnify, defend and hold TERP harmless from any and all losses, liabilities, damages, judgments, settlements and expenses, including reasonable attorneys’ fees (collectively, “Losses”), in connection with any suit, action or other proceedings brought by the Company or any other person against TERP, and Parent hereby agrees that it shall be solely responsible for, and indemnify, defend and hold TERP harmless from, any amounts payable by Parent or Merger Sub pursuant to Section 4.05(e) or Section 7.02(b) of the Merger Agreement.

1.3.2. TERP hereby agrees to indemnify Parent and Merger Sub from any and all Losses incurred by Parent and/or Merger Sub (including any reasonable increased out-of-pocket costs to Parent and/or Merger Sub to seek and obtain alternative financing to otherwise fund the Purchase Price not funded by TERP) in connection with any suit, action or other or proceeding brought by the Company against Parent and/or Merger Sub solely in connection with the breach of TERP’s obligation to fund the Purchase Price at the time and on the terms set forth in the Purchase Agreement if all of the conditions to funding in the Purchase Agreement were satisfied at the time of such funding failure; provided, however, that TERP’s indemnification obligations under this Section 1.3.2 shall be conditioned on (x) neither Parent nor Merger Sub being in breach of its obligations under the Merger Agreement (other than any obligations breached by Parent or Merger Sub solely due to the fact that TERP has breached its obligation to fund its Purchase Price pursuant to the Purchase Agreement) and (y) Parent and Merger Sub being, and demonstrating that they are, ready, willing and able to consummate or cause to be consummated the transactions contemplated by the Merger Agreement and the Purchase Agreement.

1.4. Expense Sharing. Each of Parent and TERP agrees that it will be responsible for its Pro Rata Share of all fees, costs, and expenses (including those of representatives, advisors, agents, and counsel) incurred by Parent, TERP and Merger Sub in connection with the Merger Agreement and the transactions contemplated thereby (the “Merger Expenses”); provided, that TERP shall not otherwise be liable (and shall not be required to reimburse Parent or Merger Sub) for any fees, costs or expenses incurred by Parent or Merger Sub in connection with Parent’s or Merger Sub’s arranging of financing (including any equity financing); and provided, further, that neither Parent nor Merger Sub shall otherwise be liable (and shall not be required to reimburse TERP) for any fees, costs or expenses incurred by TERP in connection with TERP’s arranging of financing (including any equity financing) of the Purchase Price; and provided, further, that the Merger Expenses shall be subject to reallocation in accordance with Section 1.3.1 or Section 1.3.2 in instances where Section 1.3 applies. Notwithstanding the foregoing, each of Parent, Merger Sub and TERP (and following the Closing, the Company) shall bear their own fees, costs and expenses incurred in connection with the Carveout Transaction. “Pro Rata Share” shall mean for Parent and Merger Sub jointly: 58% and for TERP 42%.

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1.5. Representations, Warranties and Covenants.

1.5.1. Each Party hereby represents, warrants and covenants to the other Parties that none of the information supplied in writing by such Party specifically for inclusion or incorporation by reference in the Proxy or Information Statement will cause a breach of the representations and warranties of Parent or Merger Sub set forth in Section 3.02(i) the Merger Agreement.

1.5.2. Each Party hereby represents, warrants and covenants to the other Parties that the information supplied in writing by such Party in connection with filings or notifications under, or relating to, Antitrust Law is and will be accurate and complete in all material respects.

1.5.3. Each Party represents and warrants to the other Parties that (i) such Party has full power and authority (including full corporate or other entity power and authority) to execute and deliver this Agreement and to perform its obligations hereunder; (ii) this Agreement constitutes the valid and legally binding obligation of such Party, enforceable in accordance with its terms; and (iii) the execution, delivery and performance of this Agreement and all other agreements contemplated hereby have been duly authorized by such Party.

1.6. Indemnification.

1.6.1. Each Party (an “Indemnifying Party”) shall indemnify, defend and hold each other Party (an “Indemnified Party”), its respective successors and assigns, and their respective shareholders, directors, officers, employees and agents, harmless from and against any and all Losses arising from or relating to a breach of this Agreement by the Indemnifying Party.

1.6.2. Without limiting the provisions of the foregoing Section 1.6.1, and notwithstanding any other provision of this Agreement or any other agreement between Parent or any of its affiliates (other than TerraForm Power, Inc. or TERP or any of its subsidiaries), on the one hand, and TERP or any of its subsidiaries, on the other hand (including, without limitation, the Purchase Agreement), Parent hereby agrees to indemnify TERP and its subsidiaries and to hold each of them harmless for any and all Losses arising from or relating to TERP being required to fund all or part of the Purchase Price under the Purchase Agreement in spite of a breach by Parent or Merger Sub of any of their obligations under this Agreement, without which breach TERP would not have had to make all or part of such funding. In furtherance of and not in limitation of the foregoing, Parent shall promptly (and, in any event, on the same Business Day as TERP funds under the Purchase Agreement) reimburse TERP for the full amount of such funding which TERP would not have had to make without such breach by Parent or Merger Sub.

1.7. Carveout Transaction. Parent shall, concurrently with the Closing, transfer the Carveout Assets to TERP, and Parent and TERP shall enter into one or more definitive agreements in addition to the Purchase Agreement with respect to the Carveout Transaction (together with the Purchase Agreement, the “Carveout Transaction Agreements”), which Carveout Transaction Agreements shall include the following terms and conditions and other terms and conditions that Parent and TERP approve, each acting in their sole but good faith discretion:

1.7.1. [Reserved].

1.7.2. [Reserved].

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1.7.3. Indemnification. With respect to any Carveout Assets transferred to TERP as part of the Carveout Transaction, Parent shall indemnify TERP for any losses (including reduction in projected distributions to TERP from any Carveout Assets), damages, liabilities, costs and expenses suffered or incurred by TERP as a result of:

(i) the IRS determining that the purchase price of any solar system that is a part of any Carveout Asset exceeded its actual fair market value (“FMV”) (including, but not limited to, FMV determinations inferred from the purchase price paid by TERP for such Carveout Asset);

(ii) a breach or inaccuracy in any tax representations or warranties made to TERP in the documentation for any Carveout Assets;

(iii) any inaccuracy in a tax assumption in any “base case model” approved by TERP for such Carveout Asset;

(iv) the imposition of any real or personal property taxes upon any solar system that is a part of any Carveout Asset that are in excess of those projected in the “base case model” approved by TERP for such Carveout Asset within the first 5 years of Closing;

(v) any transfer taxes being imposed on TERP in connection with the transfer of ownership of the Carveout Assets to TERP;

(vi) any fines, penalties or other Losses incurred by TERP as a result of any breach of any consumer protection laws, including any rules or regulations of the Consumer Financial Protection Bureau, with respect to the Carveout Assets (including the applicable solar systems and customer agreements);

(vii) the failure to obtain the consent of any third parties with respect to the transfer of the Carveout Assets to TERP pursuant to the Purchase Agreement; and

(viii) a breach or inaccuracy in any representations or warranties, or any of the Company’s or its subsidiaries’ covenants in the equity capital contribution agreement, limited liability company operating agreement, EPC agreement or other transaction documents relating to any of the Carveout Assets, including representations, warranties and covenants regarding the applicable solar systems and customer agreements, compliance with laws and regulations (including consumer protection laws and regulations) tax items, governmental permits and approvals, system warranties, environmental and regulatory matters and homeowner credit metrics and other portfolio composition requirements, including geographic diversity and technology, all with market standard survival periods after the Closing Date.

1.7.4. O&M Agreement. Parent shall perform certain repair obligations and other services with respect to the Carveout Assets pursuant to one or more agreements (jointly, the “O&M Agreements”) between Parent and TERP, which shall be entered into concurrently with the Closing and be consistent with the terms set forth on Exhibit A attached hereto.

1.8. Long-Term Dropdown Framework Agreement. Concurrently with the Closing, Parent (or a subsidiary of Parent whose obligations are guaranteed by Parent pursuant to a guarantee reasonably acceptable to TERP) and TERP (or a subsidiary of TERP whose obligations are guaranteed by TERP

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pursuant to a guarantee reasonably acceptable to Parent) shall enter into a long-term framework agreement (together with any ancillary agreements, the “US RSC Dropdown Agreement”) for the dropdown of a certain number of US residential and small commercial solar projects developed and constructed by the Company and its subsidiaries following the Closing, which US RSC Dropdown Agreement shall also grant TERP a call right with respect to any such projects beyond the committed dropdown number, all based on the terms set forth on Exhibit B hereto.

1.9. Finalization of Agreements. Parent and TERP shall negotiate in good faith to finalize the forms of the additional Carveout Transaction Agreements, the O&M Agreements, the US RSC Dropdown Agreement and any ancillary agreements that may be necessary or convenient, within thirty (30) days after the date of this Agreement, and in any event prior to the Closing; provided that, as regards TERP, the terms of such agreements shall be subject to approval by its Corporate Governance and Conflicts of Interest Committee of its Board of Directors.

1.10. Notices under Merger Agreement. Each of Parent and Merger Sub agrees to promptly provide TERP with copies of any demands, notices, requests, consents, or other communications that are received by Parent or Merger Sub pursuant to the Merger Agreement.

2.1. Termination. This Agreement shall become effective on the date hereof and shall terminate upon the earliest of (i) the Closing of the Carveout Transaction and the entry into the US RSC Dropdown Agreement as contemplated herein and (ii) the termination of the Merger Agreement; provided, however, that any liability for failure to comply with the terms of this Agreement shall survive any such termination. Notwithstanding the foregoing, Article 2, and Sections 1.3, 1.4, 1.5, 1.6 and 1.7.3 of this Agreement shall survive indefinitely following the termination of this Agreement.

2.2. Amendment. This Agreement may be amended or modified and the provisions hereof may be waived, only by an agreement in writing signed by each of the Parties.

2.3. Severability. In the event that any provision hereof would, under applicable law, be invalid or unenforceable in any respect, such provision shall be construed by modifying or limiting it so as to be valid and enforceable to the maximum extent compatible with applicable law. The provisions hereof are severable, and any provision hereof being held invalid or unenforceable shall not invalidate, render unenforceable or otherwise affect any other provision hereof.

2.4. No Recourse. Notwithstanding anything that may be expressed or implied in this Agreement or any document or instrument delivered in connection herewith, and notwithstanding the fact that certain of the Parties may be partnerships or limited liability companies, by its acceptance of the benefits of this Agreement, Parent and each other Party acknowledges and agrees that no Person other than the Parties has any obligations hereunder and that Parent and each other Party has no right of recovery under this Agreement or in any document or instrument delivered in connection herewith, or for any claim based on, in respect of, or by reason of, such obligations or their creation, against, and no personal liability shall attach to, the former, current and future equity holders, controlling persons, directors, officers, employees, agents, affiliates, members, managers, general or limited partners or assignees of the Parties or any former, current or future stockholder, controlling person, director, officer, employee, general or limited partner, member, manager, affiliate, agent or assignee of any of the foregoing, in each case, other than the Parties hereto (collectively, each a “Non-Recourse Party”), through Parent, Merger Sub, the Company or otherwise, whether by or through attempted piercing of the corporate veil, by or through a claim by or on behalf of Parent, Merger Sub or the Company against any Non-Recourse Party, by the enforcement of any assessment or by any legal or equitable proceeding, by

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virtue of any statute, regulation or applicable law, or otherwise. Nothing set forth in this Agreement shall confer or give or shall be construed to confer or give to any Person other than the Parties hereto (including any Person acting in a representative capacity) any rights or remedies against any Person other than as expressly set forth herein.

2.5. Further Assurances. Each Party agrees to act in good faith and to execute such further documents and perform such further acts as may be reasonably required to carry out the provisions of the Merger Agreement and the transactions contemplated thereby and effectuate the Carveout Transaction.

2.6. Construction. The Parties have participated jointly in the negotiation and drafting of this Agreement. In the event an ambiguity or question of intent or interpretation arises, this Agreement shall be construed as if drafted jointly by the Parties and no presumption or burden of proof shall arise favoring or disfavoring any Party by virtue of the authorship of any of the provisions of this Agreement. Any reference to any federal, state, local, or non-U.S. statute or law shall be deemed also to refer to all rules and regulations promulgated thereunder, unless the context requires otherwise. The word “including” shall mean including without limitation.

2.7. Governing Law; Consent to Jurisdiction. THIS AGREEMENT SHALL BE DEEMED TO BE MADE IN AND IN ALL RESPECTS SHALL BE INTERPRETED, CONSTRUED AND GOVERNED BY AND IN ACCORDANCE WITH THE LAW OF THE STATE OF DELAWARE WITHOUT REGARD TO THE CONFLICTS OF LAW PRINCIPLES THEREOF TO THE EXTENT THAT SUCH PRINCIPLES WOULD DIRECT A MATTER TO ANOTHER JURISDICTION. Each Party hereby irrevocably submit to the exclusive personal jurisdiction of the Court of Chancery of the State of Delaware, or to the extent such court does not have subject matter jurisdiction, the United States District Court for the District of Delaware (the “Chosen Courts”) solely in respect of the interpretation and enforcement of the provisions of this Agreement and of the documents referred to in this Agreement, and in respect of the transactions contemplated hereby, and hereby waive, and agree not to assert, as a defense in any action, suit or proceeding for the interpretation or enforcement hereof or of any such document, that it is not subject thereto or that such action, suit or proceeding may not be brought or is not maintainable in the Chosen Courts or that the Chosen Courts are an inconvenient forum or that the venue thereof may not be appropriate, or that this Agreement or any such document may not be enforced in or by such Chosen Courts, and the Parties hereto irrevocably agree that all claims relating to such action, suit or proceeding shall be heard and determined in the Chosen Courts. The Parties hereby consent to and grant any such Chosen Court jurisdiction over the person of such parties and, to the extent permitted by Law, over the subject matter of such dispute and agree that mailing of process or other papers in connection with any such action, suit or proceeding in the manner provided in this Section 2.7 or in such other manner as may be permitted by law shall be valid, effective and sufficient service thereof.

2.8. WAIVER OF JURY TRIAL. EACH OF PARENT, MERGER SUB, AND TERP ACKNOWLEDGES AND AGREES THAT ANY CONTROVERSY WHICH MAY ARISE UNDER THIS AGREEMENT IS LIKELY TO INVOLVE COMPLICATED AND DIFFICULT ISSUES, AND THEREFORE EACH SUCH PERSON HEREBY IRREVOCABLY AND UNCONDITIONALLY WAIVES ANY RIGHT SUCH PERSON MAY HAVE TO A TRIAL BY JURY IN RESPECT OF ANY ACTION, SUIT OR PROCEEDING DIRECTLY OR INDIRECTLY ARISING OUT OF OR RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY. EACH OF PARENT, MERGER SUB AND TERP CERTIFIES AND ACKNOWLEDGES THAT (a) NO REPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY TO THIS AGREEMENT HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THAT SUCH OTHER PARTY WOULD NOT, IN THE EVENT OF SUCH ACTION, SUIT OR PROCEEDING, SEEK TO ENFORCE THE FOREGOING WAIVER, (b) SUCH PERSON UNDERSTANDS AND HAS CONSIDERED THE IMPLICATIONS OF THIS WAIVER, (c) SUCH PERSON MAKES THIS WAIVER VOLUNTARILY

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AND (d) SUCH PERSON HAS BEEN INDUCED TO ENTER INTO THIS AGREEMENT BY, AMONG OTHER THINGS, THE MUTUAL WAIVERS AND CERTIFICATIONS IN THIS SECTION 2.8.

2.9. Exercise of Rights and Remedies. No delay of or omission in the exercise of any right, power or remedy accruing to any Party as a result of any breach or default by any other Party under this Agreement shall impair any such right, power or remedy, nor shall it be construed as a waiver of or acquiescence in any such breach or default, or of any similar breach or default occurring later, nor shall any such delay, omission or waiver of any single breach or default be deemed a waiver of any other breach or default occurring before or after such waiver. For the avoidance of doubt, nothing in the Purchase Agreement shall prejudice any rights of TERP under this Agreement.

2.10. Other Agreements. This Agreement amends, restates and supersedes the Original IA in its entirety. This Agreement, together with the agreements referenced herein, constitutes the entire agreement, and supersedes all prior agreements, understandings, negotiations and statements, both written and oral, among the parties or any of their affiliates with respect to the subject matter contained herein except for such other agreements as are referenced herein which shall continue in full force and effect in accordance with their terms.

2.11. Assignment. This Agreement may not be assigned by any Party or by operation of law or otherwise without the prior written consent of each of the other Parties, except for any collateral assignment of rights hereunder to any Party’s financing parties. Any attempted assignment in violation of this Section 2.11 shall be null and void.

2.12. No Representations or Duty. (a) Except as expressly provided herein, each Party specifically understands and agrees that no Party has made or will make any representation or warranty with respect to the terms, value or any other aspect of the transactions contemplated hereby, and each Party explicitly disclaims any warranty, express or implied, with respect to such matters from any other Party. In addition, each Party specifically acknowledges, represents and warrants that it is not relying on any other Party (i) for its due diligence concerning, or evaluation of, the Company or its assets or businesses, including but not limited to the Carveout Assets, (ii) for its decision with respect to making any investment contemplated hereby or (iii) with respect to tax and other economic considerations involved in such investment.

(b) In making any determination contemplated by this Agreement, each Party may make such determination in its sole and absolute discretion, taking into account only such Party’s own views, self-interest, objectives and concerns, except as expressly provided herein. No Party shall have any fiduciary or other duty to any other Party except as expressly set forth in this Agreement.

2.13. Counterparts. This Agreement may be executed in one or more counterparts, and by the different Parties hereto in separate counterparts, each of which when executed shall be deemed to be an original but all of which taken together shall constitute one and the same agreement.

2.14. Notices. All demands, notices, requests, consents, and communications hereunder shall be in writing and shall be deemed to have been duly given if personally delivered by courier service, messenger, or telecopy at, or if duly deposited in the mails, by certified or registered mail, postage prepaid — return receipt requested, to each Party at the address set forth on the signature pages hereto, or any other address designated by such Party in writing to the other Parties.

2.15. Specific Performance. The Parties agree that irreparable damage may occur and that the parties may not have any adequate remedy at law in the event that any of the provisions of this Agreement

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were not performed in accordance with their specific terms or were otherwise breached. It is accordingly agreed that, in the event of any breach or threatened breach by any other Party of any covenant or obligation contained in this Agreement, the non-breaching Party shall be entitled to seek an injunction or injunctions to prevent breaches of this Agreement and to enforce specifically the terms and provisions of this Agreement, without the necessity of posting bonds or similar undertakings in connection therewith, this being in addition to any other remedy which may be available to such non-breaching Party at law or in equity, including monetary damages.

[Signature pages follow]

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IN WITNESS WHEREOF, each of the undersigned has duly executed this Agreement (or caused this Agreement to be executed on its behalf by its officer or representative thereunto duly authorized) as of the date first above written.

[Signature Page to A&R Interim Agreement]

[Signature Page to A&R Interim Agreement]

EXHIBIT A

TERMS OF O&M AGREEMENTS

[See Attached]

SUMMARY OF TERMS AND CONDITIONS

O&M AGREEMENTS FOR VIVINT SOLAR DROPDOWNS

A. PARTIES TO THE TRANSACTION:

EXHIBIT B

TERMS OF US RSC DROPDOWN AGREEMENT

[See Attached]

Exhibit B

Summary of the Take/Pay Agreement

This Summary outlines certain terms of the Take/Pay Agreement referred to in the Commitment Letter. Certain capitalized terms used herein are defined in the Commitment Letter.