The German giant will start with simple products, with the main offer consisting of one-, two- and three-year deals, and packages without subscription. It will also sell LED lights.

"Our clients will be able to save EUR 100 annually and at the same time reduce their consumption by up to 15 percent," Krečar said, adding that the company would offer competitive and fair pricing.

He believes that RWE's entry in the Slovenian market will bring significant change, and that its presence will bring positive effects in terms of competition.

"I believe that our arrival will be beneficial for all consumers, including those who will not come to us."

Karl Kraus of the RWE Central and Southeast Europe management board said that RWE wanted to become one of the leading energy companies in Slovenia, noting that the Slovenian electricity supply market "is very liberalised."

According to him, the company will first focus on households, which is to be followed by business consumers and industry. RWE could later sell natural gas and will look to launch renewable projects, Kraus added.

RWE is present in 12 European markets and supplies around 24 million consumers with electricity and gas. The RWE group, which employs some 60,000 people, last year generated EUR 50bn in revenue.

According to Krečar, the company will directly and indirectly create around 150 jobs in Slovenia.