In annual terms, the country's power output was down 13%, the office of statistics said in a statement earlier this week, citing provisional data.
The July output of the country's hydropower plants decreased 52% on the year and went down 28% on a monthly comparison basis to 216 GWh.
The output of the thermal power plants in Slovenia totalled 272 GWh in July, up 54% on the year and down 4% month-on-month, while the production of Slovenia's sole nuclear power plant, Krsko, fell 2% month-on-month to 490 GWh.
In July, Slovenia imported 809 GWh of electricity and exported 761 GWh. Imports remained unchanged compared to the previous month, while exports decreased 3%.
On an annual comparison basis, imports went up 13% and exports fell 6%.
Nuclear energy had the largest share of 47.9% in Slovenia's total power production in July, followed by thermal energy with 26.6%, hydro energy with 21.1%, and solar and wind with 4.3%.