Gas-fired plants can set a high marginal price for electricity in Southeast Europe when weak hydro output, low wind or thermal outages leave them needed to balance supply. The exposure extends beyond countries with substantial gas generation: regional power trade can transmit the effect to neighbouring markets.
A modern combined-cycle gas turbine (CCGT) operating at around 55-60% efficiency requires roughly 1.7-1.8 MWh of gas input to produce 1 MWh of electricity. With gas at €90/MWh, fuel alone can cost more than €150/MWh of electricity, before carbon, variable operating and start-up costs. That fuel bill creates a high floor for marginal power prices when gas units are called on.
At gas prices of €80-100/MWh, fuel costs for an efficient CCGT are roughly €135-180/MWh of electricity. If EU ETS carbon prices and variable costs remain material, gas-fired generation can support wholesale electricity prices above €170-220/MWh during tight hours. A rise in gas prices above €120/MWh would substantially increase that indicated range.
Romania, Greece and Hungary are particularly important to regional price formation because gas-fired capacity there can influence cross-border electricity prices. Serbia is indirectly exposed through imports and regional coupling, even when its domestic gas-fired generation is limited. Bulgaria can also feel the effect through electricity trade with Greece and Romania.
Gas storage and liquefied natural gas news can move Southeast European power prices without a local gas shortage. A change in TTF shifts the opportunity cost of gas-fired generation and the electricity power bid stack, with the impact able to pass across interconnectors. Gas is not the only determinant of electricity prices, but it can become the dominant marginal input in tight winter conditions.
The relationship is likely to remain strong through winter as heating and electricity demand rise together and hydro conditions remain volatile. Weak wind in Central Europe can increase gas consumption across the interconnected system. The effect is strongest when heating demand coincides with low renewable output and limited imports.
Power traders need to monitor TTF, the Balkan Gas Hub and EU ETS carbon prices alongside hydro reservoirs, wind forecasts and cross-border capacity. Price assessments also need to account for gas prices, carbon costs, plant efficiency and available interconnector capacity together.
