Combine whose basic operation is the production of electrical energy and coal is the largest company in the Macedonian energy supply system and it is composed of two production units: Mines and Thermal Plant.

The production in the combine began in 1980, by digging out barren soil from the first BTO system (dredge, belt, disposer), and the first electrical energy was generated in 1982, when the first of the three units of the thermal power plant was started.

REK Bitola has a share of over 72% in the total energy production of the Macedonian energy system.