Eskom acting CEO Collin Matjila on Wednesday told MPs there had been no bias in the tender process that led to French company Areva securing the contract to replace six steam generators at the Koeberg nuclear power plant.

"We believe the process was beyond reproach," Matjila told members of Parliament's economic development and energy portfolio committees.

He was responding to a question from the Democratic Alliance's Gordon Mackay who asked "why the technical committee of Eskom was overruled in terms of the recommendations on Westinghouse" -- the losing bidder that has taken the matter to court.

Mackay added: "We are also incredibly concerned that it seems to be the case that Eskom board members purposely or deliberately misled the minister in terms of the information made available to her."

Matjila said there was no indication of Energy Minister Tina Joemat-Pettersson being misled and added that Eskom had a proud history of properly handling large procurement processes.

"I just want to indicate that Eskom has a very robust procurement process that it follows, and we have a proud history of a fair and objective evaluation process.

"We have handled projects of a value much higher than this one."

In the case of the Koeberg project, he said, Eskom "has implemented the integrity that has always accompanied such processes".

Matjila said he respected Westinghouse's right to launch a legal challenge. Eskom likewise had a right to protect its interests and responding more fully to MPs' questions at present could compromise the outcome of the case.

"We have subjected ourselves to that court process, the hearing of which will be on Friday.

"We are therefore constrained in terms of our ability to provide answers on the merits of the case least we prejudice that process -- save to say that we believe that there has not been any wrongdoing or partiality on the side of the Eskom procurement processes and structures in dealing with this particular matter."

Mackay asked that Eskom hand all bid documents to the energy and public enterprises committees, to obviate the need for the DA to launch a Promotion of Access to Information Act application to secure the paperwork.

Matjila said he would be happy to so once the court case had run its course.

"We will in due course, if so required and once the legal processes have been exhausted, make available the information that honourable members may require to further ensure that there is open transparency in the processes that Eskom has followed."

Westinghouse has asked the High Court in Pretoria to suspend execution of the contract and to order Eskom to hand it all the relevant documents supporting its decision to reject the Westinghouse tender.

The US embassy in Pretoria has registered its concern about the contract. Westinghouse Electric SA is a US company.

Mackay said the opposition feared the court case would lead to significant delays in upgrading Koeberg and that this would have a dire impact on the country's energy supply.