Elektroprivreda Republike Srpske AD Trebinje (ERS) is a Bosnian company that specializes in the development of renewable energy projects in the geothermal, small hydro, and wind sectors. The company is based in Trebinje, a city located in the southern part of the country, and is owned by the government of the Republika Srpska, one of the two entities that make up Bosnia and Herzegovina.

ERS was established in 2005 with the aim of providing reliable and affordable electricity to the citizens of the Republika Srpska. The company's main activities include the production, transmission, and distribution of electricity, as well as the development of renewable energy projects. ERS has a total installed capacity of 1,200 MW, which is generated by a mix of thermal, hydro, and renewable sources.

In recent years, ERS has been focusing on the development of renewable energy projects, particularly in the geothermal, small hydro, and wind sectors. These projects are seen as a way to diversify the company's energy mix, reduce its dependence on fossil fuels, and contribute to the country's energy security and sustainability.

Geothermal energy is one of the most promising sources of renewable energy in Bosnia and Herzegovina, due to the country's abundant geothermal resources. ERS has been exploring the potential of geothermal energy in the country and has identified several sites with high geothermal potential. The company has already developed a geothermal power plant in the city of Teslic, which has an installed capacity of 17.5 MW and produces around 100 GWh of electricity per year. ERS is also working on the development of several other geothermal projects in the country, including a 20 MW plant in the city of Banja Luka and a 30 MW plant in the city of Tuzla.

Small hydro is another important source of renewable energy in Bosnia and Herzegovina, due to the country's numerous rivers and streams. ERS has been developing small hydro projects in various parts of the country, with a total installed capacity of around 60 MW. These projects are typically located in remote areas and provide electricity to local communities that are not connected to the national grid. ERS is currently working on the development of several new small hydro projects, including a 10 MW plant in the city of Bijeljina and a 5 MW plant in the city of Trebinje.

Wind energy is a relatively new source of renewable energy in Bosnia and Herzegovina, but it has significant potential due to the country's favorable wind conditions. ERS has been exploring the potential of wind energy in the country and has identified several sites with high wind potential. The company has already developed a 50 MW wind farm in the city of Nevesinje, which produces around 150 GWh of electricity per year. ERS is also working on the development of several other wind projects in the country, including a 60 MW farm in the city of Foča and a 30 MW farm in the city of Gacko.

In addition to its renewable energy projects, ERS is also involved in various other activities that contribute to the development of the energy sector in Bosnia and Herzegovina. The company is responsible for the operation and maintenance of the national transmission and distribution network, which includes over 10,000 km of high-voltage transmission lines and over 30,000 km of low-voltage distribution lines. ERS is also involved in the development of new thermal power plants and the modernization of existing ones, with the aim of improving the efficiency and environmental performance of these plants.

Overall, ERS is a key player in the development of the energy sector in Bosnia and Herzegovina, particularly in the area of renewable energy. The company's focus on geothermal, small hydro, and wind projects is a testament to its commitment to sustainability and its recognition of the importance of diversifying the country's energy mix. With its extensive experience and expertise in the energy sector, ERS is well-positioned to continue leading the way in the development of renewable energy projects in Bosnia and Herzegovina.