Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MILLER W. THADDEUS
   2. Issuer Name and Ticker or Trading Symbol
CALPINE CORP [CPN] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
EVP, CLO and Secretary
(Last)
(First)
(Middle)
CALPINE CORPORATION, 717 TEXAS AVENUE, SUITE 1000		 3. Date of Earliest Transaction (Month/Day/Year)
12/31/2017
(Street)

HOUSTON, TX 77002		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)		 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)		 4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)		 5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock, par value $0.001 per share 12/31/2017   M(1)   59,622 A $ 0 (2) 120,772 D  
Common Stock, par value $0.001 per share 12/31/2017   F(3)   22,905 D $ 15.13 (4) 97,867 D  
Common Stock, par value $0.001 per share               157,381 I By December 2016 GRAT
Common Stock, par value $0.001 per share               26,967 I By Trust
Common Stock, par value $0.001 per share               11,676 I By August 2016 GRAT
Common Stock, par value $0.001 per share               40,462 I By Trust
Common Stock, par value $0.001 per share               40,462 I By Trust

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)		 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)		 5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)		 6. Date Exercisable and Expiration Date
(Month/Day/Year)		 7. Title and Amount of Underlying Securities
(Instr. 3 and 4)		 8. Price of Derivative Security
(Instr. 5)		 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stock Units $ 0 (2) 12/31/2017   M     59,622   (5)   (5) Common Stock, par value $0.001 per share 59,622 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MILLER W. THADDEUS
CALPINE CORPORATION
717 TEXAS AVENUE, SUITE 1000
HOUSTON, TX 77002		       EVP, CLO and Secretary  

Signatures

 W. Thaddeus Miller   01/03/2018
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Represents the conversion upon vesting of restricted stock units ("RSUs") into common stock of Calpine Corporation (the "Company"). On May 10, 2017, the reporting person was granted 59,622 RSUs that were previously reported on Table II of a Form 4 filed with the Securities and Exchange Commission on May 10, 2017.
(2) RSUs convert into common stock on a one-for-one basis.
(3) Represents shares withheld by the Company at the reporting person's request, as permitted under the Company's 2017 Equity Incentive Plan (the "Equity Plan"), to satisfy the reporting person's tax withholding obligation in connection with the vesting on December 31, 2017 of certain shares of restricted stock units previously awarded to the reporting person. There was no open market sale of shares by the reporting person.
(4) Closing market price of the Company common stock on Friday, December 29, 2017, representing the closing price per share on the day immediately preceding the Sunday, December 31, 2017 vesting date, on which the New York Stock Exchange was open for trading, as provided under the Equity Plan.
(5) The award vested on December 31, 2017.

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