Temelín NPP tests new spent fuel casks

1. 4. 2019

The Temelín nuclear power plant has tested a new spent fuel cask by Škoda JS. The tests took five days to complete. Power engineers tested the principal tasks for the filling and transportation of the cask from the reactor hall to the spent fuel storage. Dummy material was used instead of actual fuel. Spent fuel is planned for filling in the new cask during an outage of Unit 2, scheduled for late June. Unit 1 of the Temelín NPP has been in planned outage since 1 March; restart is scheduled for the end of April, Marek Sviták, spokesperson for the Temelín NPP, informed the Czech News Agency today. Škoda is planning to supply 60 casks to the power plant.

Expedice prvního kontejneru ŠKODA 1000/19Dispatching the first ŠKODA 1000/19 cask

The ŠKODA 1000/19 cask – The tests at the Temelín NPP carried out by power engineers were a follow-up to previous tests conducted in the spent fuel storage area. “We received the cask towards the end of the year. We initially tested the empty cask for transportation to the storage, processing in the main generation block, and handling in the storage,” says Jan Kruml, Director of Temelín NPP.

ČEZ signed the contract with Škoda JS from Pilsen in 2015. The manufacturer will be delivering 60 casks by 2035. “We will provide from two to six units per year, depending on what the Temelín plant needs,” says Bohdan Zronek, member of the Board of Directors and Director of the Nuclear Power Division at ČEZ Group. ČEZ had previously stated that the value of the contract amounts to tens to hundreds of millions of CZK per year.

During the outage at Unit 1 the engineers tested operations in the reactor hall, especially filling the cask with fuel. Dummy material was used instead of actual fuel. The material was placed into each of the 19 positions inside the cask. “We tested operations which can only be practiced during an outage. Apart from insertion of fuel, these include draining, drying of the cask, as well as installation of the lids,” Kruml said. The drying alone takes nearly a whole day.

Václav Svoboda během testování kontejneru ŠKODA 1000_19 v reaktorovém sáleVáclav Svoboda at the testing of the ŠKODA 1000/19 cask in the reactor hall

The body of the cask is a steel cylinder with an outer diameter of 2.3 meters and a length of 5.6 meters. Its empty weight is nearly 105 tons and nearly 119 tons when filled with fuel. The walls are 41 centimeters thick. Fuel can be stored in the cask for up to 60 years.

Škoda JS has been manufacturing these casks since 1995. The company has produced 400 units for nuclear power plants and installations in the Czech Republic, Germany, USA, Switzerland, Lithuania and Bulgaria. Starting in 2021, they will supply casks also for the Dukovany NPP. A total of 35 units will be produced by Škoda JS until 2031.

Unit 1 at the Temelín NPP has been in outage since March 1. The engineers have removed fuel from the generator. “Inspections are ongoing at the turbine, safety systems and other devices in the nuclear and non-nuclear parts,” Sviták said. The unit is scheduled to produce electricity again in late April.

Temelín is the leading producer of electricity in the Czech Republic, covering 1/5 of the country’s consumption. The power plant was commissioned by ČEZ in December 2000. Temelín NPP produced 15.66 TWh of electricity in the past year. The year-to-date production of electricity amounts to 3.9 TWh.

Source: Czech News Agency