Combined cycle to come up in Croatia

The Elektrana-Toplana Zagreb power plant (EL-TO Zagreb power plant) located in Trešnjevka, Zagreb, Croatia, is being modernised by replacing unit A of the plant with a new combined-cycle co-generation unit.

Hrvatska elektroprivreda (HEP), Croatia’s national energy company, is undertaking the project with an estimated investment of €214.7m (approximately $249m).

With an electrical output of 150MW and heat output of 114MW, the plant is estimated to produce 675GW of electricity, 450GW of heat, and 160GW of process steam a year.

Construction of the unit is expected to begin in 2018, with completion anticipated by the end of 2021.

The combined-cycle power unit will be equipped with two gas turbines, two heat recovery steam generators (HRSG), and one extraction back-pressure steam turbine.

Each gas turbine, combined with a generator, will have a nominal output of 50.5MW. The HRSGs will generate super-heated steam by using hot flue gases at the gas turbine exit.

With two extractions and a nominal output of 35MW, the steam turbine will be capable of operating in electricity generation and co-generation mode.

The cooling system of the plant will comprise air-cooled heat exchangers, divided into two sections. The first section will be used for cooling the steam from the steam turbine, especially during the hottest time of the year, while the other will be used for cooling certain systems of the plant such as electric generators, lubricating oil system, and feed pumps.

Process steam will be used for industrial needs, while generated heat will be used in the district heating system (DHS) of Zagreb city.