In Southeast Europe, the value of stored electricity depends on a battery’s business model and its revenue after costs, not simply on average power prices or installed capacity. As a result, investors, lenders and portfolio owners may favour different markets.
Batteries earn revenue from hourly price differences and system services, meaning average day-ahead prices do not reveal the earnings available from each usable megawatt-hour. The relevant measure is revenue per usable MWh after accounting for market volatility, competition, grid charges, fees, degradation and access to balancing services.
Storage capacity and market conditions across the region
Capacity figures show the different scales of the markets. Hungary had 1,053.4 MW of grid-scale battery capacity listed at 1 October, while Romania had 1,162 MW and 2,312 MWh of storage capacity on the same date. Bulgaria’s total exceeded 6.2 GW and 19 GWh, according to the latest estimates, although its large fleet also brings intense competition for arbitrage.
Romania combines a rapidly growing storage fleet with merchant and balancing opportunities, and has a non-recourse precedent that may make the market more attractive to banks. Hungary’s expansion is supported by market reform and a large solar base. Bulgaria’s scale and mature dispatch experience may suit portfolio owners combining storage with large solar assets.
Serbia’s operating storage fleet is smaller than those in the other markets discussed, while stronger price volatility may offer wider scarcity margins because flexibility is scarcer. Standalone projects there also face greater regulatory and financing uncertainty. A pure merchant trader may prefer a less saturated market, whereas a portfolio owner may value Bulgaria’s solar assets and dispatch experience.
Market rankings can change depending on the business model and the costs of accessing the market. Investors should model the same battery configuration in each market with identical technical assumptions before deciding where an asset is worth most. The comparison should include competition, fees, degradation and balancing access, rather than rely on average spot prices or capacity totals.