EXHIBIT 21  MISSION ENERGY HOLDING COMPANY  LIST OF SUBSIDIARIES  As of March 22, 2002

|Entity                                       |  | Jurisdiction Of Organization
|-------------------------------------------- |  | ----------------------------
|Adelaide Ventures Limited                    |  | Cayman Islands              
|Aguila Energy Company                        |  | California                  
|Anacapa Energy Company                       |  | California                  
|Arrowhead Energy Company (Inactive)          |  | California                  
|Athens Funding, L.L.C.                       |  | Delaware                    
|Balboa Energy Company                        |  | California                  
|Beheer-en Beleggingsmaatschappij Jydeno B.V. |  | The Netherlands             
|Blue Ridge Energy Company                    |  | California                  
|Bretton Woods Energy Company                 |  | California                  
|Bretton Woods Funding I, L.L.C.              |  | Delaware                    
|Camino Energy Company                        |  | California                  
|Caresale Services Limited                    |  | United Kingdom              
|Centerport Energy Company                    |  | California                  
|Chesapeake Bay Energy Company                |  | California                  
|Chester Energy Company                       |  | California                  
|Chestnut Ridge Energy Company                |  | California                  
|Citizens Power Holdings One, LLC             |  | Delaware                    
|CL Power Sales Eight, L.L.C.                 |  | Delaware                    
|CL Power Sales Nine, L.L.C.                  |  | Delaware                    
|CL Power Sales One, L.L.C.                   |  | Delaware                    
|CL Power Sales Seven, L.L.C.                 |  | Delaware                    
|CL Power Sales Six, L.L.C.                   |  | Delaware                    
|CL Power Sales Ten, L.L.C.                   |  | Delaware                    
|CL Power Sales Two, L.L.C.                   |  | Delaware                    
|Clayville Energy Company                     |  | California                  
|Coaltrade Services International Pte Ltd     |  | Singapore                   
|Collins Holdings EME, LLC                    |  | Delaware                    
|Colonial Energy Company (Inactive)           |  | California                  
|Coronado Energy Company                      |  | California                  
|CP Power Sales Eighteen, L.L.C.              |  | Delaware                    
|CP Power Sales Fifteen, L.L.C.               |  | Delaware                    
|CP Power Sales Five, L.L.C.                  |  | Delaware                    
|CP Power Sales Fourteen, L.L.C.              |  | Delaware                    
|CP Power Sales Nineteen, L.L.C.              |  | Delaware                    
|CP Power Sales Seventeen, L.L.C.             |  | Delaware                    
|CP Power Sales Thirteen, L.L.C.              |  | Delaware                    

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|CP Power Sales Twelve, L.L.C.                      |  | Delaware        
|-------------------------------------------------- |  | ----------------
|CP Power Sales Twenty, L.L.C.                      |  | Delaware        
|Crescent Valley Energy Company (Inactive)          |  | California      
|Del Mar Energy Company                             |  | California      
|Delaware Energy Conservers, Inc. (Inactive)        |  | Delaware        
|Desert Sunrise Energy Company (Inactive)           |  | Nevada          
|Devereaux Energy Company                           |  | California      
|East Maine Energy Company (Inactive)               |  | California      
|EcoElectrica Holdings, Ltd.                        |  | Cayman Islands  
|EcoElectrica Ltd.                                  |  | Cayman Islands  
|EcoElectrica S.a.r.l.                              |  | Luxembourg      
|Edison Alabama Generating Company                  |  | California      
|Edison First Power Holdings I                      |  | United Kingdom  
|Edison First Power Holdings II                     |  | United Kingdom  
|Edison First Power Limited                         |  | Guernsey        
|Edison Mission Advantage B.V.                      |  | The Netherlands 
|Edison Mission Ausone Pty. Ltd.                    |  | Australia       
|Edison Mission Development, Inc.                   |  | Delaware        
|Edison Mission Energy                              |  | Delaware        
|Edison Mission Energy Asia Pacific Pte. Ltd.       |  | Singapore       
|Edison Mission Energy Asia Pte Ltd.                |  | Singapore       
|Edison Mission Energy Australia Pilbara Power Ltd. |  | Australia       
|Edison Mission Energy Australia Ltd.               |  | Australia       
|Edison Mission Energy Fuel                         |  | California      
|Edison Mission Energy Fuel Company Pte Ltd.        |  | Singapore       
|Edison Mission Energy Fuel Services, LLC           |  | Delaware        
|Edison Mission Energy Funding Corp.                |  | Delaware        
|Edison Mission Energy Holdings Pty. Ltd.           |  | Australia       
|Edison Mission Energy Interface Ltd.               |  | British Columbia
|Edison Mission Energy International B.V.           |  | The Netherlands 
|Edison Mission Energy Limited                      |  | United Kingdom  
|Edison Mission Energy Oil & Gas                    |  | California      
|Edison Mission Energy Petroleum                    |  | California      
|Edison Mission Energy Power (Inactive)             |  | Mauritius       
|Edison Mission Energy Services B.V.                |  | The Netherlands 
|Edison Mission Energy Services, Inc.               |  | California      
|Edison Mission Energy Taupo Limited                |  | New Zealand     
|Edison Mission Finance Co.                         |  | California      
|Edison Mission Fuel Resources, Inc.                |  | Delaware        
|Edison Mission Fuel Transportation, Inc.           |  | Delaware        

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|Edison Mission Holdings Co.                                                  |  | California     
|---------------------------------------------------------------------------- |  | ---------------
|Edison Mission LYB PEDS Pty Ltd (formerly Edison Mission De Laide Pty. Ltd.) |  | Australia      
|Edison Mission Marketing & Trading, Inc.                                     |  | California     
|Edison Mission Marketing and Services Limited                                |  | United Kingdom 
|Edison Mission Midwest Holdings Co.                                          |  | Delaware       
|Edison Mission Millennium B.V.                                               |  | The Netherlands
|Edison Mission Operation & Maintenance (Thailand) Company Limited            |  | Thailand       
|Edison Mission Operation & Maintenance Kwinana Pty Ltd.                      |  | Australia      
|Edison Mission Operation & Maintenance Limited                               |  | United Kingdom 
|Edison Mission Operation & Maintenance Loy Yang Pty Ltd.                     |  | Australia      
|Edison Mission Operation & Maintenance Services B.V.                         |  | The Netherlands
|Edison Mission Operation & Maintenance Services Pte Ltd                      |  | Singapore      
|Edison Mission Operation & Maintenance, Inc.                                 |  | California     
|Edison Mission Overseas Co.                                                  |  | Delaware       
|Edison Mission Overseas Ltd.                                                 |  | United Kingdom 
|Edison Mission Project Co.                                                   |  | Delaware       
|Edison Mission Retail Pty Ltd.                                               |  | Australia      
|Edison Mission Services Limited                                              |  | United Kingdom 
|Edison Mission Utilities Pty Ltd.                                            |  | Australia      
|Edison Mission Vendesi Pty Ltd.                                              |  | Australia      
|Edison Mission Wind Power Italy B.V.                                         |  | The Netherlands
|El Dorado Energy Company                                                     |  | California     
|EME Adelaide Energy Ltd.                                                     |  | United Kingdom 
|EME Ascot Limited                                                            |  | United Kingdom 
|EME Atlantic Holdings Limited                                                |  | United Kingdom 
|EME Buckingham Limited                                                       |  | United Kingdom 
|EME Caliraya B.V.                                                            |  | The Netherlands
|EME CP Holdings Co.                                                          |  | Delaware       
|EME del Caribe                                                               |  | Cayman Islands 
|EME del Caribe Holding GmbH                                                  |  | Austria        
|EME Desarrello Espana S.L.                                                   |  | Spain          
|EME Eastern Holdings Co.                                                     |  | Delaware       
|EME Finance UK Limited                                                       |  | United Kingdom 
|EME Generation Holdings Limited                                              |  | United Kingdom 
|EME International Dragon Limited                                             |  | United Kingdom 
|EME Investments, LLC                                                         |  | Delaware       
|EME Kalayaan B.V.                                                            |  | The Netherlands
|EME Monet Limited                                                            |  | United Kingdom 

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|EME Philippines Services Corporation (formerly EME Philippines O&M Corporation) |  | The Philippines
|------------------------------------------------------------------------------- |  | ---------------
|EME Precision B.V.                                                              |  | The Netherlands
|EME Royale                                                                      |  | New Zealand    
|EME Southwest Power Corporation                                                 |  | Delaware       
|EME Tri Gen B.V.                                                                |  | The Netherlands
|EME UK International LLC                                                        |  | Delaware       
|EME Victoria B.V. (Inactive)                                                    |  | The Netherlands
|EME Victoria Generation Limited                                                 |  | United Kingdom 
|EMP, Inc. (Inactive)                                                            |  | Oregon         
|Energy Generation Finance PLC                                                   |  | United Kingdom 
|Enerloy Pty Ltd                                                                 |  | Australia      
|First Hydro Company                                                             |  | United Kingdom 
|First Hydro Finance plc                                                         |  | United Kingdom 
|First Hydro Holdings Company                                                    |  | United Kingdom 
|First Hydro Renewables Limited                                                  |  | United Kingdom 
|Four Counties Gas Company (Inactive)                                            |  | California     
|Gippsland Power Pty Ltd                                                         |  | Australia      
|Global Generation B.V.                                                          |  | The Netherlands
|Global Power Investors, Inc.                                                    |  | California     
|Hancock Generation LLC                                                          |  | Delaware       
|Holtsville Energy Company                                                       |  | California     
|Homer City Property Holdings, Inc.                                              |  | California     
|Hydro Energy B.V.                                                               |  | The Netherlands
|Iberian Hy-Power Amsterdam B.V.                                                 |  | The Netherlands
|Iberica de Energias, S.L.                                                       |  | Spain          
|Indian Bay Energy Company                                                       |  | California     
|Jefferson Energy Company (Inactive)                                             |  | California     
|Kings Canyon Energy Company (Inactive)                                          |  | California     
|Kingspark Energy Company                                                        |  | California     
|La Jolla Energy Company (Inactive)                                              |  | California     
|Laguna Energy Company (Inactive)                                                |  | California     
|Lakeland Power Development Company                                              |  | United Kingdom 
|Lakeland Power Ltd.                                                             |  | United Kingdom 
|Lakeview Energy Company                                                         |  | California     
|Latrobe Power Pty. Ltd.                                                         |  | Australia      
|Latrobe Valley B.V. (formerly Beheer-en Beleggingsmaatschappij Botara B.V.)     |  | The Netherlands
|Lehigh River Energy Company (Inactive)                                          |  | California     
|Longview Cogeneration Company                                                   |  | California     
|Loy Yang Holdings Pty Ltd                                                       |  | Australia      

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|Loyvic Pty. Ltd.                                    |  | Australia      
|--------------------------------------------------- |  | ---------------
|Madera Energy Company                               |  | California     
|Madison Energy Company                              |  | California     
|Majestic Energy Limited                             |  | United Kingdom 
|Maplekey Holdings Limited                           |  | United Kingdom 
|Maplekey UK Finance Limited                         |  | United Kingdom 
|Maplekey UK Limited                                 |  | United Kingdom 
|MEC Esenyurt B.V.                                   |  | The Netherlands
|MEC IES B.V.                                        |  | The Netherlands
|MEC India B.V.                                      |  | The Netherlands
|MEC Indo Coal B.V.                                  |  | The Netherlands
|MEC Indonesia B.V.                                  |  | The Netherlands
|MEC International B.V.                              |  | The Netherlands
|MEC International Holdings B.V.                     |  | The Netherlands
|MEC Laguna Power B.V.                               |  | The Netherlands
|MEC Perth B.V.                                      |  | The Netherlands
|MEC Priolo B.V.                                     |  | The Netherlands
|MEC San Pascual B.V.                                |  | The Netherlands
|MEC Sidi Krir B.V.                                  |  | The Netherlands
|MEC Sumatra B.V.                                    |  | The Netherlands
|MEC Wales B.V.                                      |  | The Netherlands
|Midwest Generation EME, LLC                         |  | Delaware       
|Midwest Generation, LLC                             |  | Delaware       
|Midwest Peaker Holdings, Inc.                       |  | Delaware       
|Mission Contact Finance Limited                     |  | New Zealand    
|Mission De Las Estrellas LLC                        |  | Delaware       
|Mission Del Cielo Inc.                              |  | Delaware       
|Mission Del Sol, LLC                                |  | Delaware       
|Mission Energy (Kwinana) Pty. Ltd.                  |  | Australia      
|Mission Energy Company (UK) Limited                 |  | United Kingdom 
|Mission Energy Construction Services, Inc.          |  | California     
|Mission Energy Development Australia Pty Ltd        |  | Australia      
|Mission Energy Five Star                            |  | New Zealand    
|Mission Energy Generation, Inc. (Inactive)          |  | California     
|Mission Energy Holdings International, Inc.         |  | California     
|Mission Energy Holdings Superannuation Fund Pty Ltd |  | Australia      
|Mission Energy Holdings, Inc.                       |  | California     
|Mission Energy Indonesia (Inactive)                 |  | California     
|Mission Energy Italia s.r.l.                        |  | Italy          
|Mission Energy Mexico (Inactive)                    |  | California     

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|Mission Energy New York, Inc.                                                     |  | California     
|--------------------------------------------------------------------------------- |  | ---------------
|Mission Energy Pacific Holdings (formerly EME Pacific Holdings)                   |  | New Zealand    
|Mission Energy Universal Holdings (formerly EME Universal Holdings)               |  | New Zealand    
|Mission Energy Ventures Australia Pty Ltd                                         |  | Australia      
|Mission Energy Wales Company                                                      |  | California     
|Mission Energy Westside, Inc.                                                     |  | California     
|Mission Hydro (UK) Limited                                                        |  | United Kingdom 
|Mission NZ Operations B.V. (Inactive)                                             |  | The Netherlands
|Mission Operations de Mexico, S.A. de C.V. (Inactive)                             |  | Mexico         
|Mission Triple Cycle Systems Company                                              |  | California     
|Mission/Eagle Energy Company (Inactive)                                           |  | California     
|Morningstar Holdings B.V. (formerly Beheer-en Beleggingsmaatschappij Vestra B.V.) |  | The Netherlands
|North Jackson Energy Company (Inactive)                                           |  | California     
|Northern Sierra Energy Company                                                    |  | California     
|Ortega Energy Company                                                             |  | California     
|P.T. Edison Mission Operation & Maintenance Indonesia                             |  | Indonesia      
|Panther Timber Company                                                            |  | California     
|Paradise Energy Company (Inactive)                                                |  | California     
|Pleasant Valley Energy Company                                                    |  | California     
|Pocono Fuels Company (Inactive)                                                   |  | California     
|Pride Hold Limited                                                                |  | United Kingdom 
|Quartz Peak Energy Company                                                        |  | California     
|Rapid Energy Limited                                                              |  | United Kingdom 
|Rapidan Energy Company                                                            |  | California     
|Redbill Contracts Limited                                                         |  | United Kingdom 
|Reeves Bay Energy Company                                                         |  | California     
|Ridgecrest Energy Company                                                         |  | California     
|Rio Escondido Energy Company                                                      |  | California     
|Riverport Energy Company                                                          |  | California     
|San Gabriel Energy Company (Inactive)                                             |  | California     
|San Joaquin Energy Company                                                        |  | California     
|San Juan Energy Company                                                           |  | California     
|San Pedro Energy Company                                                          |  | California     
|Santa Ana Energy Company                                                          |  | California     
|Santa Clara Energy Company                                                        |  | California     
|Silver Springs Energy Company                                                     |  | California     
|Silverado Energy Company                                                          |  | California     
|Sonoma Geothermal Company (Inactive)                                              |  | California     
|South Australian Holdings Ltd.                                                    |  | United Kingdom 

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|South Coast Energy Company              |  | California     
|--------------------------------------- |  | ---------------
|Southern Sierra Energy Company          |  | California     
|Southern Sierra Gas Company             |  | California     
|Southwestern Generation B.V.            |  | The Netherlands
|Sunapee Funding I, L.L.C.               |  | Delaware       
|Thorofare Energy Company (Inactive)     |  | California     
|Traralgon Power Pty. Ltd.               |  | Australia      
|Viejo Energy Company                    |  | California     
|Vindoor Investments (Mauritius) Limited |  | Mauritius      
|Vista Energy Company (Inactive)         |  | New Jersey     
|Western Sierra Energy Company           |  | California     

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