The Polish government on Tuesday issued regulation to reduce power supply, mostly at large-scale companies consuming more than 300kW, citing the continuing heat wave and difficulties with cooling power plants.

The restrictions concern 1,600 companies including factories, steel mills and energy-intensive industrial plants. It will not, however, cause any inconvenience for institutions responsible for the country's security and well-being such as hospitals and other "vulnerable subjects" or private households.

On Monday, Polish Electricity Networks said "limitation of production capacity due to continued difficulties with cooling the power plants, as well as emergency withdrawals" made it necessary to introduce the restrictions.

Poland's most important power plant in Belchatow also suffered a breakdown Sunday.

However, experts point out that Poland's electricity networks are obsolete and underinvested. Until 2020, Poland is supposed to spend 100 billion zloty (26 billion U.S. dollars) on the modernization of network systems.

The latest restrictions introduced by the government are supposed to last until Aug. 30.

Polish Prime Minister Ewa Kopacz believes the reduction will not have a negative influence on companies.

However, firms have been forced to decrease production, including ArcelorMittal Poland, a leading steel manufacturer, Kompania Weglowa, a coal mining company, and Jastrzebska Spolka Weglowa, EU's largest coking coal producer.

This is the first reduction in Poland's power supply since the 1980s.

Poland has been experiencing temperatures of up to 35 to 38 Celsius degrees in some regions.