The transmission tariff - the economic tool for the network infrastructure development

The free access to the transmission network is one of the key elements of the electricity market development both at the national and regional levels. The operation of the electricity market needs the appropriate development of its basic infrastructure, the transmission network. In the frame work of the electricity market, the network ensures the electricity transmission under reliable conditions, from the generators to the suppliers and eligible consumers and creates market opportunities for its users. One of the main market tools, which may influence the optimal development of the network structure, by an efficient location signal of the large consumers and generators, is the pricing system. The overall costs of the Transmission System Operator (TSO) for providing the transmission service may be distinctly focused by categories as follows: - Costs of the existing transmission network (fixed costs), maintenance and operation costs, capital costs; - Costs of electricity losses (variable costs); - Development costs needed to eliminate the network congestion (variable costs). The recovery of all costs involved by the transmission service is based on regulated tariff system approved by ANRE. By the tariff system, the transmission and system operator aims both to cover the transmission service cost and provide locational signals for all market players which should lead to the efficient grid operation as well as to the optimal development of its structure. The tariff values reflect the polarization existing in the Romanian Power System (PS), namely: surplus power in the South area of the PS (4G zone) and a power deficit in the North areas of the PS (2G and 5G zones). Electricity demand is more evenly distributed in the territory than the electricity generated. This assertion is based on the following statement: - the tariffs value range of electricity delivered in the transmission network is wider, between 1.13 and 2.39 USD/MWh (51%) than the one related to the zones of electricity received from the transmission network, between 1.64 and 2.37 USD/MWh (31%); The locational signal provided by the tariff is mitigated in certain respects by the average cost component related to the fixed costs, which represent 70% of the total costs of the transmission system operator