FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
X	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* ECP ControlCo, LLC (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol DYNEGY INC. [ DYN ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 01/09/2018
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

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	01/09/2018		S		5,250,000	D	$11.79	14,291,152	I	See footnotes(1)(2)

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 Securities Underlying Derivative Security (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: 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

1. Name and Address of Reporting Person* ECP ControlCo, LLC (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS III, LLC (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* Energy Capital Partners GP III, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS III, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS III-A, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* Energy Capital Partners III-B (Terawatt IP), LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* ENERGY CAPITAL PARTNERS III-C, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* Terawatt Holdings GP, LLC (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

1. Name and Address of Reporting Person* Terawatt Holdings, LP (Last) (First) (Middle) 51 JOHN F. KENNEDY PARKWAY SUITE 200 (Street) SHORT HILLS NJ 07078 (City) (State) (Zip)

Explanation of Responses:

1. Terawatt Holdings, LP is the record holder of the securities reported herein. ECP Control Co, LLC ("ECP Control Co") is the managing member of Energy Capital Partners III, LLC ("ECP GP"), which is the general partner of Energy Capital Partners GP III, LP ("ECP Fund GP"), which is the general partner of each of Energy Capital Partners III, LP, Energy Capital Partners III-A, Energy Capital Partners III-B (Terawatt IP), LP and Energy Capital Partners III-C, LP (collectively, the "ECP Funds"), which are the sole members of Terawatt Holdings GP, LLC ("Terawatt GP"), which is the general partner of Terawatt Holdings, LP.

2. Douglas Kimmelman, Thomas Lane, Andrew Singer, Peter Labbat, Tyler Reeder and Rahman D'Argenio are the managing members of ECP ControlCo and share the power to vote and dispose of the securities beneficially owned by ECP ControlCo. As such, each of Terawatt GP, the ECP Funds, ECP Fund GP, ECP GP, ECP ControlCo and Messrs. Kimmelman, Lane, Singer, Labbat, Reeder and D'Argenio may be deemed to have or share beneficial ownership of the Common Stock held directly by Terawatt Holdings. Each such entity or individual disclaims any such beneficial ownership except to the extent of their pecuniary interest therein.

	ECP ControlCo, LLC By: /s/ Andrew D. Singer, Manging Member	01/11/2018
	Energy Capital Partners III, LLC By: ECP ControlCo, LLC, its managing member By: /s/ Andrew D. Singer, Manging Member	01/11/2018
	Energy Capital Partners GP III, LP By: Energy Capital Partners III, LLC, its general partner By: ECP ControlCo, LLC, its managing member By: /s/ Andrew D. Singer, Manging Member	01/11/2018
	Energy Capital Partners III, LP By: Energy Capital Partners GP III, LP, its general partner By: Energy Capital Partners III, LLC, its general partner By: ECP ControlCo, LLC, its managing member By: /s/ Andrew D. Singer, Manging Member	01/11/2018
	Energy Capital Partners III-A, LP By: Energy Capital Partners GP III, LP, its general partner By: Energy Capital Partners III, LLC, its general partner By: ECP ControlCo, LLC, its managing member By: /s/ Andrew D. Singer, Manging Member	01/11/2018
	Energy Capital Partners III-B (Terawatt IP), LP By: Energy Capital Partners GP III, LP, its general partner By: Energy Capital Partners III, LLC, its general partner By: ECP ControlCo, LLC, its managing member By: /s/ Andrew D. Singer, Manging Member	01/11/2018
	Energy Capital Partners III-C, LP By: Energy Capital Partners GP III, LP, its general partner By: Energy Capital Partners III, LLC, its general partner By: ECP ControlCo, LLC, its managing member By: /s/ Andrew D. Singer, Manging Member	01/11/2018
	Terawatt Holdings GP, LLC By: /s/ Andrew D. Singer, Secretary and General Counsel	01/11/2018
	Terawatt Holdings, LP By: Terawatt Holdings GP, LLC, its general partner By: /s/ Andrew D. Singer, Secretary and General Counsel	01/11/2018
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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