Hot and hot water are the most common thermal carriers, but older high-pressure steam transports still account for about a quarter of the primary distribution, resulting in more losses in the system. [90] As regards the structure of the market, in 2016 there were 338 heat suppliers licensed for the production and/or distribution of heat, of which 87% were both producers and distributors. Most are small companies that operate in a single municipality, but some large companies such as Veolia are also present on the market. The state owns and operates large cogeneration plants that produce district heating and electricity in six cities (Bratislava, Košice, Žilina, Trnava, Zvolen and Martin). Several companies can operate in the same city, which is the case in large cities.
