After almost three years of ecological rehabilitation works, generator 5 of the Šoštanj Thermal Power Plant (TEŠ) started sending electricity into the Slovenian network again on Thursday, 16 August 2018, at 8:50 p.m., starting a two-month phase of testing and trial operation. The ecological rehabilitation of generator 5 was intended for reducing the levels of emissions of harmful substances in flue gases. In comparison with generator 4, which was recently shut down permanently, these emissions are 60% lower for nitrogen oxides (NOx), 50% lower for sulphur dioxide (SO2) and as much as 80% lower for dust particles.

With the installed power of 345 MW, generator 5 was launched in 1978. As it failed to reach the prescribed permissible level of nitrogen oxide emissions, it was shut down on 6 October 2015, with its revitalisation and ecological rehabilitation starting on 1 September 2017. The cost of these modernisation works amounted to more than EUR 10 million. “The biggest share of the investment represented the device for decomposition of nitrogen oxides (NOx), connecting the generator to a 220 kV overhead power line with the replacement of the generator transformer, upgrading of the generator management system and replacement of re-heating collectors,” explained Branko Debeljak, the executive director of the technical sector of TEŠ, and added: ”The revitalised generator is expected to be in operation until 2030, in the case of increased electricity needs or as a back-up for generator 6, when it is being repaired or overhauled.” It has been estimated by TEŠ that generator 5 could produce up to 1500 GWh of electricity a year.

After the permanent shut-down of the oldest and outdated generators 1 to 3 years ago, and this year’s shut-down of generator 4, TEŠ currently operates with the ecologically rehabilitated and revitalised generator 5, with the 600-megawatt generator 6 and two 42 MW gas units. With its share in total electricity production in Slovenia at 36%, the newly revitalised power plant will contribute to the cleaner environment in the Šalek Valley and, consequently, to improving the quality of life of the local population.

The ecological rehabilitation of generator 5 was completed ahead of schedule, which had envisaged the renewed synchronisation with the electricity network on 3 September.