BESS project profitability for investors: key legal and regulatory insights from Austria and Romania

Battery energy storage systems (BESS) have emerged as one of the most compelling asset classes in the energy transition. As renewable energy capacity continues to expand across Europe, the ability to store and dispatch electricity efficiently has become a critical component of modern energy infrastructure. For investors looking to enter or grow their exposure in this space, understanding the regulatory and commercial landscape is essential – and the contrasting frameworks in Austria and Romania offer a revealing case study.

Austria: navigating a maturing regulatory landscape

Austria has taken significant steps toward providing legal clarity for BESS operators. The recently adopted Austrian Electricity Act (ElWG) introduces a formal definition of energy storage, recognising BESS as a distinct category within the electricity system. Under the current framework, BESS is classified as electricity generation, meaning operators must obtain the full suite of relevant permits – including electricity, building and nature conservation permits.

One of the more complex aspects of the Austrian regime relates to system charges. Because BESS functions as both a consumer and a generator depending on the direction of energy flow, operators can currently face a double-charging situation – paying fees both when drawing energy from the grid and when injecting it. This represents a meaningful cost consideration for project economics.

However, Austrian law does provide a significant relief mechanism. BESS projects that qualify as operating in a “system-supportive” manner can benefit from a 20-year exemption from grid usage and grid loss charges on energy withdrawn for storage. It is up to the regulator to define what “system supportive” means in an ordinance. Currently, the draft issued by the regulator proposes relatively high requirements: to qualify, a project must meet several cumulative conditions – a minimum bottleneck capacity of 1 MW, a valid flexibility services contract with the control zone manager APG, inclusion in the relevant grid development plan and participation in public tenders for grid-connection capacity. Grid operators also retain rights to impose operational requirements regarding power range and reactive power.

For investors, this regime creates a clear trade-off: compliance with the system-supportive framework offers substantial long-term cost relief and planning certainty, but introduces dependencies on location, tender outcomes and operational constraints that must be factored into project structuring from the outset.

Romania: two routes to profitability

Romania presents a more commercially driven landscape, where BESS is attracting strong investor interest through two primary models.

The first is hybrid BESS – storage integrated with existing or new solar or wind assets. This model is well suited to investors seeking stable, infrastructure-style returns. By storing renewable energy and dispatching it during peak-price periods, hybrid BESS increases the value of electricity sold, smooths revenue volatility and improves utilisation of both the generation asset and its grid-connection point. Revenue is anchored largely through long-term, fixed-price agreements, reducing exposure to spot-market fluctuations.

The second model is stand-alone BESS, which participates directly in system-level markets – including balancing services, congestion management support and energy price arbitrage. This approach carries greater income variability, as returns depend on market activity, price volatility and the procurement needs of the transmission system operator. However, the upside potential is correspondingly higher, particularly in markets where demand for balancing services is growing or where supply of such services remains limited.

Matching investor profile to project type

The choice between these models is not simply a financial one – it also reflects investor appetite and capabilities. Hybrid BESS projects are best suited to utilities, private energy companies with established renewables portfolios and corporate offtakers seeking predictable, long-term income streams. Stand-alone BESS, by contrast, is better aligned with infrastructure funds targeting higher yields or with investors with active energy-trading capabilities and the expertise to navigate market fluctuations.

Conclusion

BESS investment in Central and Eastern Europe offers genuine opportunity, but success depends on a clear-eyed assessment of the regulatory environment and a well-matched investment strategy. Whether navigating Austria’s system-supportive exemption framework or structuring a hybrid or stand-alone project in Romania, early legal and commercial structuring is key to unlocking value and managing risk.

Wolf Theiss advises clients across the full lifecycle of BESS projects – from regulatory analysis and permitting through development, as well as project finance and long-term contract structuring. We would be happy to discuss how these frameworks apply to your specific investment objectives.