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CAPSTONE TURBINE CORPORATION

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*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on. You are receiving this communication because you hold shares in the above named company. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. Meeting Information Barcode capstone Meeting Type: For holders as of: Date: Time: Location: 0000426028_1 R1.0.1.18 CAPSTONE TURBINE CORPORATION CAPSTONE TURBINE CORPORATION 16640 STAGG STREET VAN NUYS,CA 91406 Investor Address Line 1 Investor Address Line 2 Investor Address Line 3 Investor Address Line 4 Investor Address Line 5 John Sample 1234 ANYWHERE STREET ANY CITY, ON A1A 1A1 Annual Meeting July 03, 2019 August 29, 2019 August 29, 2019 11:00 AM PDT Lewitt, Hackman, Shapiro, Marshall & Harlan 16633 Ventura Boulevard Eleventh Floor Encino, CA 91436 See the reverse side of this notice to obtain proxy materials and voting instructions. Broadridge Internal Use Only Job # Envelope # Sequence # # of # Sequence # 0000426028_1 R1.0.1.18

*** Exercise Your Right to Vote *** Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to Be Held on August 29, 2019 CAPSTONE TURBINE CORPORATION Date: August 29, 2019Time: 11:00 AM PDT 16633 Ventura Boulevard Encino, CA 91436 You are receiving this communication because you hold shares in the above named company. This is not a ballot. You cannot use this notice to vote these shares. This communication presents only an overview of the more complete proxy materials that are available to you on the Internet. You may view the proxy materials online at www.proxyvote.com or easily request a paper copy (see reverse side). We encourage you to access and review all of the important information contained in the proxy materials before voting. 1234567 1234567 Envelope # # of # Sequence # 1 OF 2 12 15 0000426028_1 R1.0.1.18 Broadridge Internal Use Only Job # Sequence # See the reverse side of this notice to obtain proxy materials and voting instructions. CAPSTONE TURBINE CORPORATION 16640 STAGG STREET VAN NUYS,CA 91406 Investor Address Line 1 Investor Address Line 2 Investor Address Line 3 Investor Address Line 4 Investor Address Line 5 John Sample 1234 ANYWHERE STREET ANY CITY, ON A1A 1A1 1234567 1234567 1234567 234567 Meeting Information Meeting Type: Annual Meeting For holders as of: July 03, 2019 Location: Lewitt, Hackman, Shapiro, Marshall & Harlan Eleventh Floor B A R C O D E

Before You Vote How to Access the Proxy Materials Proxy Materials Available to VIEW or RECEIVE:  Have the information that is printed in the box marked by the arrow (located on the  by the arrow (located on the following page) in the subject line. How To Vote Please Choose One of the Following Voting Methods  marked by the arrow available and follow the instructions. Only 0000426028_2 R1.0.1.18 Vote In Person: Many stockholder meetings have attendance requirements including, but not limited to, the possession of an attendance ticket issued by the entity holding the meeting. Please check the meeting materials for any special requirements for meeting attendance. At the meeting, you will need to request a ballot to vote these shares. Vote By Internet: To vote now by Internet, go to www.proxyvote.com. Have the information that is printed in the box Vote By Mail: You can vote by mail by requesting a paper copy of the materials, which will include a proxy card. Internal Use 1. Annual Report2. Notice & Proxy Statement How to View Online: following page) and visit: www.proxyvote.com. How to Request and Receive a PAPER or E-MAIL Copy: If you want to receive a paper or e-mail copy of these documents, you must request one. There is NO charge for requesting a copy. Please choose one of the following methods to make your request: 1) BY INTERNET:www.proxyvote.com 2) BY TELEPHONE:1-800-579-1639 3) BY E-MAIL*:sendmaterial@proxyvote.com * If requesting materials by e-mail, please send a blank e-mail with the information that is printed in the box marked Requests, instructions and other inquiries sent to this e-mail address will NOT be forwarded to your investment advisor. Please make the request as instructed above on or before August 15, 2019 to facilitate timely delivery.

The Board of Directors recommends you vote FOR the following: 1. Election of Directors Nominees 01 Holly A. Van Deursen 06 Gary J. Mayo 02 Paul D. DeWeese 07 Robert F. Powelson 03 Robert C. Flexon 04 Darren R. Jamison 05 Yon Y. Jorden The Board of Directors recommends you vote FOR the following: 2. Approve an amendment to increase the number of shares available under the Capstone Turbine Corporation 2017 Equity Incentive Plan by 3.0 million; 3. Approve an amendment to Capstone's Second Amended and Restated Certificate of Incorporation, as amended, to effect a reverse stock split of our outstanding shares of Company common stock by a ratio within the range of 1-for-5 to 1-for-10, as determined in the sole discretion of our Board of Directors; 4. Approve the NOL Rights Agreement, dated as of May 6, 2019, with Broadridge Financial Solutions, Inc.; 5. Advisory vote to approve the compensation of the Company's named executive officers as presented in the proxy statement; 6. Ratification of the selection of Marcum LLP as the Company's independent registered public accounting firm for the fiscal year ending March 31, 2020; and NOTE: Such other business as may properly come before the meeting or any adjournment thereof. xxxxxxxxxx Cusip Envelope # # of # Sequence # 0000426028_3 R1.0.1.18 Broadridge Internal Use Only xxxxxxxxxx Job # Sequence # B A R C O D E 23456789012 2 2 2 2 12345678901 12345678901 12345678901 12345678901 12345678901 12345678901 12345678901 12345678901 12345678901 12345678901 Voting items