The conference ‘Polish Power Plants’ of the Polish Economic Society with the participation of the National Centre for Research and Development on the ‘200+ Program’ was held on 28-29 March in Warsaw.

The development of renewable power industry mostly based on uncontrolled sources (wind energy, photovoltaics) limits the operating time of currently working 200 MW coal-fired power units and forces them to work with greater variability of the load. Most of such power units need to continue the operation to ensure the power consumption plan in the system. They will, however, work shorter, with a large number of shutdowns and restarts, and their installed capacity will be used less frequently during a year. During the conference, a paper developed by the EPK specialists and delivered by Adam Rajnysz on the use of Duo-Blocks in the modernisation of 200 MW steam power units, was presented. According to the forecasts of the Transmission System Operator, conventional, subcritical coal-fired power units will be used in the following operating regimes;

• below 1,500 h/year and with 50 start-ups a year,
• 1,500 – 4,000 h/year, and some of them will be started up 100 to 200 times a year, and some even up to 300 times a year,
• above 4,000 h/year.

Due to the need to adapt 200 MW power units for the new operating regimes, it will be necessary to develop and implement innovative technologies to meet the above conditions. Some power units are considered to be kept as cold reserve and maintained for longer periods. The operation of units of centrally dispatched power generating facilities under such operating regimes results in a significant increase in the costs of energy production which are even higher due to the growing environmental requirements (ETS Directive, IED, BAT conclusions). To ensure the energy security and meet the above assumptions, power units of centrally dispatched power generating facilities should be modernised to ensure their maximum availability and acceptable efficiency at the lowest cost during their long life (even by 2035).

To perform the tasks arising from the change in the operating regimes of power units, the National Centre for Research and Development intends to launch a program aimed at the development and selection of appropriate technical and formal solutions for the modernisation of subcritical steam power units, in particular, 200 MW power units. The extension of the operating time of 200 MW power units should provide some time needed to make optimal – for the national economy – decisions regarding investments in new generation sources, including the subsequent and anticipated changes in the availability of new technologies of electricity production, storage, and use.