Czech nuclear power plant operator ?EZ has launched what it calls one of its largest nuclear tenders in the past 20 years - for two new steam generators for the Temelín nuclear power plant. They are expected to increase output from 1125 MWe to 1150 MWe and will have an anticipated lifespan of 40 years.

The existing generators are the largest in the Czech Republic (Image: ?EZ)

The plan is for the new steam generators to be installed at Temelín between 2028 and 2030, which would be about halfway through the current anticipated 60-year lifespan of the units which started-up in 2000 and 2002 respectively.

Bohdan Zronek, director of ?EZ's nuclear energy division, said that the aim was to have selected the supplier by next spring, with the equipment replaced at the end of the decade.

Jan Kruml, director of the Temelín plant, said: "We want to operate the power plant for at least 60 years. We will change the generators in the middle of this period and we will demand a 40-year lifespan for them."

The tender is open until 9 June and is to "supply two complete generators including one spare rotor, accessories, installation and subsequent service".

The total weight of the generator rotor is 90 tonnes and it is more than 14 metres long. The steam turbine rotates at a speed of 3000 revolutions per minute. The current ones were made in Pilsen and are the only two of their kind in the Czech Republic.

Earlier this year ?EZ said it was investing in modernising the Temelin plant to prepare it for at least 60 years of operation, and also extending its operating cycle from a year to about 18 months. Two VVER-1000 units are in operation at Temelin.

The Czech Republic already uses nuclear power for 34% of its electricity, generating this from four reactors at Dukovany and two at Temelín. ?EZ has been evaluating bids for the construction of a new reactor at Dukovany and near Temelín, an area has been designated the South Bohemia Nuclear Park and earmarked for small reactors to operate in the early 2030s.