As of today, energy companies do not have funds to increase their reserves of fuel for the next heating season, Kharchenko said.

"Today, the deficit of the energy sector is at least 3 GW,” he said.

“If we start the next [heating] season with the current condition and situation that we have now at power plant blocks, we will have a deficit of 6 to 9 GW constantly, which will be impossible to compensate for with imports of electricity from Russia and Belarus."

According to the expert, in the 2015-2016 heating season, Ukraine may again be faced with the need to introduce a schedule of rolling blackouts, as the country saw in the 1990s and in December last year.

"If the energy sector do not receive resources to carry out purchases of fuel, coal, reserve fuel, and to perform repairs, then next season we will not have a power system as a whole," the expert warned.

As UNIAN reported earlier, in January-February 2015, Ukraine saw coal production fall by more than two times - to 4.6 million tonnes - on a year-over-year basis.

For the first time in many years, Ukraine is experiencing an acute shortage of thermal coal. Feeding thermal power plants with domestically produced coal is almost impossible today due to the fighting in the east of the country, where the majority of the country’s existing mines are located.

About 50% of the electricity in Ukraine is generated by nuclear power plants, with the rest produced by thermal power plants by burning coal and gas, as well as by hydro power plants and "green" energy. Gas shortages and the shutdown of 80% of the country’s mines has led to a shortage of energy and, as a result, electricity.