Exhibit 21.1

Subsidiaries of Atlantic Power Corporation

(as of February 27, 2019)

Subsidiary |  | State of Organization
Atlantic Power Holdings, LLC | Delaware
Atlantic Power Services, LLC | Delaware
Atlantic Piedmont Holdings, LLC | Delaware
Atlantic Power (US) GP Holdings, Inc. | Delaware
AP USGP Holdings, LLC | Delaware
Atlantic CDP, Inc. | Delaware
Piedmont Green Power, LLC | Delaware
Atlantic Cadillac Holdings, LLC | Delaware
Cadillac Renewable Energy, LLC | Delaware
Orlando Power Generation I, LLC | Delaware
Orlando Power Generation II, LLC | Delaware
Orlando Cogen Limited, LP | Delaware
Baker Lake Hydro, LLC | Delaware
Olympia Hydro, LLC | Delaware
Koma Kulshan Associates, a California Limited Partnership | California
Harbor Capital Holdings, LLC | Delaware
Epsilon Power Partners, LLC | Delaware
Chambers Cogeneration Limited Partnership | Delaware
Atlantic Ridgeline Holdings, LLC. | Delaware
Delta Person LLC | Delaware
Epsilon Power Funding, LLC. | Delaware
Teton East Coast Generation, LLC. | Delaware
Teton Selkirk, LLC | Delaware
Teton Power Funding, LLC | Delaware
Atlantic Power Services Canada GP Inc. | British Columbia
Atlantic Power Services Canada LP | Ontario
Atlantic Power Limited Partnership (f/k/a Capital Power Income L.P.) | Ontario
Atlantic Power GP Inc. (f/k/a CPI Income Services Ltd.) | British Columbia
Atlantic Power Preferred Equity Ltd. (f/k/a CPI Preferred Equity Ltd.) | Alberta
Atlantic Power Energy Services (Canada) Inc. (f/k/a CP Energy Services (Canada) Inc.) | British Columbia
Atlantic Power (US) GP (f/k/a CP Power (US) GP) | Delaware
Atlantic Power (Coastal Rivers) Corporation (f/k/a Coastal Rivers Power Corporation) | British Columbia
Atlantic Power (Williams Lake) Ltd. (f/k/a CPI Power (Williams Lake) Ltd.) | British Columbia
Atlantic Power FPLP Holdings LLC (f/k/a CPI FPLP Holdings LLC) | Delaware
Frederickson Power Management Inc. | Washington
Atlantic Power GP II Inc. | British Columbia
APLP Holdings Limited Partnership | Ontario
Frederickson Power LP | Washington
APDC, Inc. (f/k/a CPIDC, Inc.) | Washington
AP Power Holdings LLC (f/k/a CPI Power Holdings Inc.) | Delaware
Atlantic Power USA LLC (f/k/a CPI Power USA LLC) | Delaware
Atlantic Power USA Holdings LLC (f/k/a CPI Power Holdings USA LLC) | Delaware
Atlantic Power Enterprises LLC (f/k/a CPI Power Enterprises LLC) | Delaware

Subsidiary |  | State of Organization
Manchief LLC. | Delaware
Manchief Holding LLC | Delaware
Manchief Power Company LLC | Delaware
Curtis Palmer LLC | Delaware
AP (Curtis Palmer) LLC | Delaware
Curtis/Palmer Hydroelectric Company L.P. | New York
Atlantic Power Energy Services (US) LLC (f/k/a CPI Energy Services (US) LLC) | Delaware
Morris Cogeneration, LLC | Delaware
Atlantic Power USA Ventures, LLC (f/k/a CPI USA Ventures LLC) | Delaware
EF Oxnard LLC | California
EF Kenilworth LLC | California
Applied Energy LLC | California
Ridgeline Energy Holdings LLC | Delaware
Ridgeline Energy LLC | Delaware
Ridgeline Energy Solar LLC | Delaware
Atlantic Midway Ventures LLC | Delaware
Allendale Biomass LLC | Delaware
Atlantic Decker Energy, Inc. | California
Decker Energy – Craven GP LLC | Delaware
Decker Energy – Craven LP LLC | Delaware
Decker Energy Grayling, Inc. | Delaware
Dorchester Biomass, LLC | Delaware
AJD Forest Products Limited Partnership | Michigan
Craven County Wood Energy LP | Delaware
GGS Holdings Company | Delaware
Grayling Development Partners | Michigan
Grayling Partners Land Development, LLC | Michigan
Grayling Generating Station Limited Partnership | Michigan
Javelin Energy, LLC | Delaware