UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934 (Amendment No.           )

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☐ Preliminary Proxy Statement

☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))

☐ Definitive Proxy Statement

☒ Definitive Additional Materials

☐ Soliciting Material Pursuant to §240.14a-12

FuelCell Energy, Inc.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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On March 26, 2021, the following information was sent via Federal Express and U.S. Mail to certain beneficial owners of FuelCell Energy, Inc.’s common stock:

IMPORTANT REMINDER TO VOTE YOUR PROXY

         March 26,2021

DearStockholder:

The annual meeting of stockholders of FuelCell Energy, Inc. is scheduled to be held on Thursday, April 8, 2021 at 10:00 a.m. Eastern Daylight Time.

As an investor in FuelCell Energy now is the opportunity to vote your shares. It is very important that all stockholders have their voices heard.   MacKenzie Partners has been engaged by FuelCell Energy to assist ingathering the votes for the Special Meeting.  Nomatterhowmanysharesyouholdyourvoteisveryimportant.MacKenziePartnerscantakeyourvoteviatelephoneoremail.Tovoteviaphonepleasecall800-322-2885(Toll-FreeintheUS)or212-929-5500.We urge you to please vote your shares today.  

YoumayalsocontactMacKenziePartnerswithyourvotinginstructions via emailatjjaegers@mackenziepartners.com.

Hereisasampleemail;

To:jjaegers@mackenziepartnes.com

Dear Mr. Jaegers

PleaseletthisemailserveasmyauthorizationtovotemysharesofFuelCellEnergy,Inc.commonstockasfollows:

1. FOR each Director Nominee: To elect five directors to serve until the 2022 Annual Meeting of Stockholders and until their successors are duly elected and qualified.

2. FOR: To ratify the selection of KPMG LLP as FuelCell Energy, Inc.’s independent registered public accounting firm for the fiscal year ending October 31, 2021.

3. FOR: To approve, on a non-binding advisory basis, the compensation of FuelCell Energy, Inc.’s named executive officers as set forth in the “Executive Compensation” section of the Proxy Statement.

4. FOR: To approve the amendment of the FuelCell Energy, Inc. Certificate of Incorporation, as amended, to increase the number of authorized shares of common stock of FuelCell Energy, Inc. from 337,500,000 shares to 500,000,000 shares (the “Increase Authorized Shares Proposal”).

5. FOR: To approve the amendment and restatement of the FuelCell Energy, Inc. 2018 Omnibus Incentive Plan, as amended and restated.

Thesharesareregisteredinthenameof

PleasecontactMacKenziePartnerstodaysotheymayassistinprocessingyourvote–thiswillonlytakeafewminutesofyourtime butwill save FuelCellEnergy thecost of additionalmailings.

Sincerely,

FuelCellEnergy,Inc.