Exhibit 8.0

Investments in subsidiary undertakings

|Name and nature of business                                 |  | Country of
incorporation and
registration |  | Type of share     |  | Group effective
shareholding |  
|----------------------------------------------------------- |  | ----------------------------------------- |  | ----------------- |  | ---------------------------- | -
|Gippsland Power Pty Limited*(Power generation)              |  | Australia                                 |  | Ordinary Shares   |  | 70                           | %
|Hazelwood Power Partnership*(Power generation)              |  | Australia                                 |  | Partners' Capital |  | 92                           | %
|Latrobe Power Partnership*(Power generation)                |  | Australia                                 |  | Partners' Capital |  | 70                           | %
|Perth Power Partnership*(Power generation)                  |  | Australia                                 |  | Partners' Capital |  | 49                           | %
|Synergen Power Pty Limited*(Power generation)               |  | Australia                                 |  | Ordinary Shares   |  | 100                          | %
|Canunda Power Pty Limited*(Wind power)                      |  | Australia                                 |  | Ordinary Shares   |  | 100                          | %
|Valley Power Pty Limited*(Power generation)                 |  | Australia                                 |  | Ordinary Shares   |  | 70                           | %
|International Power (Cayman) Limited(Financing company)     |  | Cayman Islands**                          |  | Ordinary Shares   |  | 100                          | %
|Elektrárny Opatovice A.S.*(Power generation)                |  | Czech Republic                            |  | Ordinary Shares   |  | 99                           | %
|Deeside Power Development Company Limited(Power generation) |  | England and Wales                         |  | Ordinary Shares   |  | 100                          | %
|First Hydro Company *(Power generation)                     |  | England and Wales                         |  | Ordinary Shares   |  | 70                           | %
|First Hydro Finance plc *(Financing company)                |  | England and Wales                         |  | Ordinary Shares   |  | 70                           | %
|IPM Eagle LLP *(Investment holding company)                 |  | England and Wales                         |  | Partners' Capital |  | 70                           | %
|Normanglade 4 LLP *(Financing company)                      |  | England and Wales                         |  | Partners' Capital |  | 70                           | %
|Pelican Point Power Limited*(Power generation)              |  | England and Wales                        |  | Ordinary Shares   |  | 100                          | %
|Rugeley Power Limited(Power generation)                     |  | England and Wales                         |  | Ordinary Shares   |  | 100                          | %
|IPR Insurance Company Limited*(Insurance captive)           |  | Guernsey                                  |  | Ordinary Shares   |  | 100                          | %
|International Power (Jersey) Limited(Financing company)     |  | Jersey**                                  |  | Ordinary Shares   |  | 100                          | %
|Al Kamil Power Company SAOG*(Power generation)              |  | Oman                                      |  | Ordinary Shares   |  | 65                           | %
|TurbogásProdutora Energetica S.A*(Power generation)        |  | Portugal                                  |  | Ordinary Shares   |  | 75                           | %
|Tihama Power Generation Company Limited*(Power generation)  |  | Saudi Arabia                              |  | Ordinary Shares   |  | 60                           | %
|Electro Metalúrgica del Ebro SL(Power generation)           |  | Spain                                     |  | Ordinary Shares   |  | 64                           | %
|Ibérica de Enérgías SL(Power generation)                    |  | Spain                                     |  | Ordinary Shares   |  | 70                           | %
|                                                            |  |                                           |  |                   |  |                              |  

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|Thai National Power Company Limited*(Power generation)   |  | Thailand |  | Ordinary Shares   |  | 100 | %
|-------------------------------------------------------- |  | -------- |  | ----------------- |  | --- | -
|ANP Bellingham Energy Company, LLC*(Power generation)    |  | US       |  | Ordinary Shares   |  | 100 | %
|ANP Blackstone Energy Company, LLC*(Power generation)    |  | US       |  | Ordinary Shares   |  | 100 | %
|ANP Funding I, LLC*(Financing company)                   |  | US       |  | Ordinary Shares   |  | 100 | %
|Hays Energy Limited Partnership*(Power generation)       |  | US       |  | Partners' Capital |  | 100 | %
|Midlothian Energy Limited Partnership*(Power generation) |  | US       |  | Partners' Capital |  | 100 | %
|Milford Power Limited Partnership*(Power generation)     |  | US       |  | Partners' Capital |  | 100 | %

All
subsidiary undertakings operate in their country of incorporation, except as indicated below. All subsidiary undertakings have a 31 December year end. The Group also has a
number of overseas branch offices.

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