Exhibit 8.1

Exhibit 8.1 Scottish Power plc Subsidiaries at 31 March 2006



|  |  |                                         |  |         |  |              
|- |  | --------------------------------------- |  | ------- |  | -------------
|  |  | Subsidiary                              |  | % Owned |  | Group % Owned
|1 |  | Scottish Power Finance (Jersey) Limited |  | 100     |  | 100          
|1 |  | Scottish Power UK Group Limited         |  | 100     |  | 100          
|2 |  | Scottish Power UK Holdings Limited      |  | 100     |  | 100          
|3 |  | Callagheen Wind Farm Limited            |  | 100     |  | 100          
|3 |  | Coldham Windfarm Limited                |  | 80      |  | 80           
|3 |  | Scottish Power Intermediate Limited     |  | 100     |  | 100          
|3 |  | Scottish Power UK plc                   |  | 100     |  | 100          
|4 |  | Aspen 1 Limited                         |  | 100     |  | 100          
|4 |  | Caledonian Gas Limited                  |  | 100     |  | 100          
|4 |  | Camjar plc                              |  | 100     |  | 100          
|5 |  | Spotlight Trading Limited               |  | 100     |  | 100          
|5 |  | Telephone Information Services plc      |  | 100     |  | 100          
|4 |  | Core Utility Solutions Limited          |  | 50      |  | 100          
|4 |  | Manweb Limited                          |  | 100     |  | 100          
|4 |  | RoboScot (38) Limited                   |  | 50      |  | 50           
|4 |  | SaBRe Water Limited                     |  | 100     |  | 100          
|4 |  | Scottish Power Trustees Limited         |  | 100     |  | 100          
|4 |  | Scottish Utility Services Limited       |  | 100     |  | 100          
|4 |  | ScottishPower Generation Limited        |  | 100     |  | 100          
|5 |  | Beaufort Energy Limited                 |  | 100     |  | 100          
|6 |  | CRE Energy Limited                      |  | 100     |  | 100          
|7 |  | Morecambe Wind Limited                  |  | 33.33   |  | 33.33        
|6 |  | Wind Resources Limited                  |  | 45      |  | 45           
|7 |  | Carland Cross Limited                   |  | 100     |  | 45           
|7 |  | Coal Clough Limited                     |  | 100     |  | 45           
|5 |  | CeltPower Limited                       |  | 50      |  | 50           
|5 |  | Emerald Power Generation Limited        |  | 100     |  | 100          
|5 |  | Manweb Generation Holdings Limited      |  | 100     |  | 100          
|6 |  | Manweb Generation (Winnington) Limited  |  | 100     |  | 100          
|5 |  | Scotash Limited                         |  | 50      |  | 100          
|5 |  | ScottishPower (SCPL) Limited            |  | 100     |  | 100          
|5 |  | ScottishPower (SOCL) Limited            |  | 100     |  | 100          
|5 |  | SMW Limited                             |  | 100     |  | 100          
|4 |  | ScottishPower Investments Limited       |  | 100     |  | 100          
|5 |  | Caledonian Communications Limited       |  | 100     |  | 100          
|5 |  | Dornoch International Insurance Limited |  | 100     |  | 100          
|5 |  | Genscot Limited                         |  | 100     |  | 100          
|5 |  | Manweb Holdings Limited                 |  | 100     |  | 100          
|6 |  | Manweb Contracting Services Limited     |  | 100     |  | 100          
|6 |  | Manweb Gas Limited                      |  | 100     |  | 100          
|6 |  | Manweb Pensions Trustee Limited         |  | 100     |  | 100          
|5 |  | Mawlaw 526 Limited                      |  | 100     |  | 100          
|5 |  | Scotsgrid Limited                       |  | 100     |  | 100          
|5 |  | Scotspower Limited                      |  | 100     |  | 100          
|5 |  | ScottishPower Energy Retail Limited     |  | 100     |  | 100          
|6 |  | Gemserv Limited                         |  | 7.82    |  | 13.38        
|6 |  | Manweb Energy Consultants Limited       |  | 100     |  | 100          
|6 |  | N.E.S.T.MAKERS Limited                  |  | 50      |  | 50           
|6 |  | NFPA Holdings Limited                   |  | 8.33    |  | 8.33         
|6 |  | St. Clements Services Limited           |  | 12.5    |  | 12.5         
|5 |  | ScottishPower Finance Limited           |  | 100     |  | 100          
|5 |  | ScottishPower Insurance Limited         |  | 100     |  | 100          
|5 |  | ScottishPower Leasing Limited           |  | 100     |  | 100          



---

|  |  |                                                  |  |      |  |      
|- |  | ------------------------------------------------ |  | ---- |  | -----
|5 |  | ScottishPower Securities Limited                 |  | 100  |  | 100  
|5 |  | ScottishPower Telecommunications Limited         |  | 100  |  | 100  
|6 |  | Demon Internet Limited                           |  | 100  |  | 100  
|7 |  | Cityscape Global Media Limited                   |  | 100  |  | 100  
|7 |  | Cityscape Internet Services Limited              |  | 100  |  | 100  
|7 |  | Cityscape Limited                                |  | 100  |  | 100  
|7 |  | Demon Limited                                    |  | 100  |  | 100  
|7 |  | Dispatch Publishing Limited                      |  | 100  |  | 100  
|7 |  | Locomotive Software Group Limited                |  | 100  |  | 100  
|8 |  | Locomotive Software Developments Limited         |  | 100  |  | 100  
|8 |  | Turnpike 1996 Limited                            |  | 100  |  | 100  
|8 |  | Turnpike Limited                                 |  | 100  |  | 100  
|7 |  | The IP Systems Operation Limited                 |  | 100  |  | 100  
|6 |  | Lancastrian Holdings Limited                     |  | 100  |  | 100  
|7 |  | Megafone (UK) Limited                            |  | 100  |  | 100  
|7 |  | Psychic Companions Limited                       |  | 100  |  | 100  
|6 |  | SPPT Limited                                     |  | 100  |  | 100  
|6 |  | Watermark Games Limited                          |  | 100  |  | 100  
|5 |  | SP Manweb plc                                    |  | 100  |  | 100  
|6 |  | ElectraLink Limited                              |  | 6.19 |  | 13.36
|6 |  | Gemserv Limited                                  |  | 2.78 |  | 13.38
|6 |  | Manweb Nominees Limited                          |  | 100  |  | 100  
|6 |  | Manweb Services Limited                          |  | 100  |  | 100  
|6 |  | Manweb Share Scheme Trustees Limited             |  | 100  |  | 100  
|5 |  | SSEB Limited                                     |  | 100  |  | 100  
|4 |  | ScottishPower Share Scheme Trustees Limited      |  | 100  |  | 100  
|4 |  | ScottishPower Sharesave Trustees Limited         |  | 100  |  | 100  
|4 |  | Selectusonline Limited                           |  | 25   |  | 25   
|4 |  | SP Dataserve Limited                             |  | 100  |  | 100  
|4 |  | SP Distribution Limited                          |  | 100  |  | 100  
|5 |  | ElectraLink Limited                              |  | 7.17 |  | 13.36
|5 |  | Gemserv Limited                                  |  | 2.78 |  | 13.38
|5 |  | Scottish Electricity Settlements Limited         |  | 50   |  | 50   
|4 |  | SP Gas Limited                                   |  | 100  |  | 100  
|4 |  | SP Power Systems Limited                         |  | 100  |  | 100  
|5 |  | Core Utility Solutions Limited                   |  | 50   |  | 100  
|4 |  | SP Transmission Limited                          |  | 100  |  | 100  
|4 |  | Teledata (Holdings) Limited                      |  | 100  |  | 100  
|5 |  | Teledata (Outsourcing) Limited                   |  | 100  |  | 100  
|6 |  | The CallCentre Service Limited                   |  | 100  |  | 100  
|5 |  | Teledata Scotland Limited                        |  | 100  |  | 100  
|5 |  | The Information Service Limited                  |  | 100  |  | 100  
|6 |  | Clubcall Telephone Services Limited              |  | 100  |  | 100  
|6 |  | Clubline Services Limited                        |  | 100  |  | 100  
|4 |  | Telephone International Media Holdings Limited   |  | 100  |  | 100  
|5 |  | Copperteam Limited                               |  | 100  |  | 100  
|5 |  | Telephone International Media Limited            |  | 100  |  | 100  
|5 |  | TIM Limited                                      |  | 100  |  | 100  
|3 |  | ScottishPower (DCL) Limited                      |  | 100  |  | 100  
|4 |  | Damhead Creek Finance Limited                    |  | 100  |  | 100  
|4 |  | ScottishPower (DCOL) Limited                     |  | 100  |  | 100  
|3 |  | ScottishPower Energy Management (Agency) Limited |  | 100  |  | 100  
|3 |  | ScottishPower Energy Management Limited          |  | 100  |  | 100  
|1 |  | ScottishPower Finance V Limited                  |  | 100  |  | 100  
|1 |  | ScottishPower Inc.                               |  | 100  |  | 100  
|1 |  | ScottishPower NA 1 Limited                       |  | 100  |  | 100  



---

|  |  |                                                 |  |      |  |     
|- |  | ----------------------------------------------- |  | ---- |  | ----
|1 |  | ScottishPower NA 2 Limited                      |  | 100  |  | 100 
|2 |  | ScottishPower Holdings, Inc.                    |  | 100  |  | 100 
|3 |  | Pacific Klamath Energy, Inc.                    |  | 100  |  | 100 
|3 |  | PacifiCorp Group Holdings Company               |  | 100  |  | 100 
|4 |  | New Energy Holdings I, Inc.                     |  | 100  |  | 100 
|5 |  | EnergyWorks Holdings I                          |  | 100  |  | 100 
|4 |  | PACE Group, Inc.                                |  | 100  |  | 100 
|4 |  | PacifiCorp Energy Ventures, Inc.                |  | 100  |  | 100 
|5 |  | Black Light (Minority Interest)                 |  | 0.05 |  | 0.05
|5 |  | Nth Power Technologies Fund I, L.P.             |  | 19   |  | 19  
|4 |  | PacifiCorp Financial Services, Inc.             |  | 100  |  | 100 
|5 |  | Birmingham Syn Fuel I, Inc.                     |  | 100  |  | 100 
|5 |  | Leblon Sales Corporation                        |  | 100  |  | 100 
|5 |  | Pacific Development (Property), Inc.            |  | 100  |  | 100 
|5 |  | Pacific Harbor Capital, Inc.                    |  | 100  |  | 100 
|6 |  | PFI International, Inc.                         |  | 100  |  | 100 
|6 |  | PHC Properties Corporation                      |  | 100  |  | 100 
|5 |  | PCC Holdings, Inc.                              |  | 100  |  | 100 
|6 |  | Hillsborough Leasing Services, Inc.             |  | 100  |  | 100 
|4 |  | PacifiCorp International Group Holdings Company |  | 100  |  | 100 
|5 |  | PacifiCorp Hazelwood Pty Ltd.                   |  | 100  |  | 100 
|6 |  | Hazelwood Australia, Inc.                       |  | 100  |  | 100 
|7 |  | Hazelwood Ventures, Inc.                        |  | 100  |  | 100 
|8 |  | Hazelwood Finance LP                            |  | 12.8 |  | 12.8
|4 |  | PacifiCorp Trans, Inc.                          |  | 100  |  | 100 
|3 |  | PPM Energy, Inc.                                |  | 100  |  | 100 
|4 |  | Atlantic Renewable Energy Corporation           |  | 100  |  | 100 
|5 |  | Casselman Windpower LLC                         |  | 100  |  | 100 
|5 |  | Chestnut Ridge Windpower LLC                    |  | 100  |  | 100 
|5 |  | West Virginia Windpower LLC                     |  | 100  |  | 100 
|4 |  | Atlantic Renewable Projects LLC                 |  | 100  |  | 100 
|5 |  | Flat Rock Windpower II LLC                      |  | 50   |  | 100 
|5 |  | Flat Rock Windpower LLC                         |  | 50   |  | 100 
|4 |  | Big Horn Wind Project LLC                       |  | 100  |  | 100 
|4 |  | Dillon Wind LLC                                 |  | 100  |  | 100 
|4 |  | Eastern Desert Power, LLC                       |  | 100  |  | 100 
|4 |  | Elk River Wind, LLC                             |  | 100  |  | 100 
|4 |  | Enstor, Inc.                                    |  | 100  |  | 100 
|5 |  | Brentwood Gas Storage LLC                       |  | 100  |  | 100 
|5 |  | City Gate L.L.C.                                |  | 100  |  | 100 
|5 |  | Columbia Gas Storage L.L.C.                     |  | 100  |  | 100 
|5 |  | Delta Gas Storage L.L.C.                        |  | 100  |  | 100 
|5 |  | Enstor Louisiana LLC                            |  | 100  |  | 100 
|5 |  | Enstor Operating Company, LLC                   |  | 100  |  | 100 
|6 |  | Houston Hub Storage and Transportation, L.P.    |  | 100  |  | 100 
|6 |  | Katy Storage and Transportation, L.P.           |  | 100  |  | 100 
|6 |  | Waha Storage & Transportation, L.P.             |  | 100  |  | 100 
|5 |  | Grama Ridge Storage and Transportation, LLC     |  | 100  |  | 100 
|5 |  | Houston Hub Storage and Transportation, L.P.    |  | 100  |  | 100 
|4 |  | Heartland Wind LLC                              |  | 100  |  | 100 
|5 |  | Flying Cloud Power Partners, LLC                |  | 100  |  | 100 
|4 |  | Klamath Energy LLC                              |  | 100  |  | 100 
|4 |  | Klamath Generation LLC                          |  | 100  |  | 100 
|4 |  | Klondike Wind Power II LLC                      |  | 100  |  | 100 
|4 |  | Klondike Wind Power III LLC                     |  | 100  |  | 100 
|4 |  | Klondike Wind Power LLC                         |  | 100  |  | 100 



---

|  |  |                                         |  |     |  |    
|- |  | --------------------------------------- |  | --- |  | ---
|4 |  | Leaning Juniper Wind Power LLC          |  | 100 |  | 100
|4 |  | Manzana Wind LLC                        |  | 100 |  | 100
|4 |  | MinnDakota Wind, LLC                    |  | 100 |  | 100
|4 |  | Moraine Wind II LLC                     |  | 100 |  | 100
|4 |  | Moraine Wind LLC                        |  | 100 |  | 100
|4 |  | Mountain View Green LLC                 |  | 100 |  | 100
|4 |  | Mountain View Power Partners III, LLC   |  | 100 |  | 100
|4 |  | Pacific Wind Development LLC            |  | 100 |  | 100
|4 |  | Phoenix Wind Power LLC                  |  | 100 |  | 100
|4 |  | PPM Colorado Wind Ventures, Inc.        |  | 100 |  | 100
|5 |  | Colorado Wind Ventures, LLC             |  | 50  |  | 50 
|6 |  | Colorado Green Holdings, LLC            |  | 100 |  | 50 
|4 |  | PPM Wind Energy LLC                     |  | 100 |  | 100
|4 |  | PPM Wind Management LLC                 |  | 100 |  | 100
|4 |  | Rugby Wind LLC                          |  | 100 |  | 100
|4 |  | Scenic Vista Wind Power, LLC            |  | 100 |  | 100
|4 |  | Shiloh I Wind Project LLC               |  | 100 |  | 100
|4 |  | Trimont Wind I LLC                      |  | 100 |  | 100
|4 |  | Twin Buttes Wind LLC                    |  | 100 |  | 100
|4 |  | West Valley Leasing Company, LLC        |  | 100 |  | 100
|3 |  | ScotPower Limited                       |  | 100 |  | 100
|4 |  | ScotPower UK                            |  | 50  |  | 100
|3 |  | Scottish Power Finance (US), Inc.       |  | 100 |  | 100
|1 |  | ScottishPower Overseas Holdings Limited |  | 100 |  | 100
|2 |  | PPM Energy Canada Limited               |  | 100 |  | 100
|1 |  | SP Finance                              |  | 100 |  | 100
|1 |  | SP Finance 2 Limited                    |  | 100 |  | 100
|1 |  | SP Finance 4 Limited                    |  | 100 |  | 100
|1 |  | SP Finance 5 Limited                    |  | 100 |  | 100