The energy price you have to pay as a consumer consists of three components: the energy price, the network charges and taxes and surcharges.
The energy price is what you pay the supplier for the product it delivers, i.e. for the energy. In the liberalised Austrian natural gas market, suppliers compete with each other. The price is set by each supplier individually.
The network charges go to the system operator. These network charges are not set by the companies themselves but by E-Control, the competent regulatory authority.
The third portion of the energy bill are the taxes and surcharges which are levied by the state, the federal provinces or the municipalities. This also includes the support payments for renewable energy charged to all electricity consumers. And of course electricity and gas are subject to VAT.