The Democratic Alliance has welcomed an investigation into the activities of power utility Eskom.
DA MP, Natasha Michael says the probe by the Special Investigating Unit is a chance to hold the parastatal accountable for South Africa's electricity problems.
On Tuesday, Eskom said the SIU investigation had been authorised by presidential proclamation.
The SIU would be examining the procurement of coal and transport services, and also look at any undisclosed interests held in companies doing business with Eskom.