Bulgaria’s energy sector has seen a wave of activity over the past year, spanning offshore oil and gas exploration, large-scale renewables, and battery storage projects, keeping CMS Sofia’s Energy, Projects, and Construction team at full speed, according to Partner Kostadin Sirleshtov. Backed by strong investor interest and a more stable regulatory environment, the sector’s upward trend looks set to continue into 2025.
CEELM: What’s been keeping your firm’s energy team busy over the past year?
Sirleshtov: It’s been a very active year, with a strong mix of headline deals and ongoing work across different segments of the energy sector. We’ve been busy, particularly upstream oil and gas, renewables, and energy storage.
On the oil and gas side, we’ve continued our long-standing work with OMV Offshore Bulgaria. We helped secure a 23-month extension of their exploration agreement for the Han Asparuh offshore block, which created opportunities for new drilling activities. That work also led to a successful farm-out to NewMed Energy Balkan earlier this year. We’ve been supporting OMV since 2011, so it’s been great to see the project evolve.
Another key highlight was advising Shell on the Han Tervel offshore block. That tender finally launched after some delays, and Shell won the bid. We supported them throughout the tender process and in signing the exploration agreement with the Bulgarian government.
On the renewables front, there’s been a lot of movement too. We helped Solar Park Trakya wrap up the development and licensing of their 50-megawatt Sinotovo photovoltaic project – and secure EUR 32 million in financing from Eurobank. There are more components still to come, including battery storage and a water-from-waste facility, so we’re continuing to support their growth.
We were also involved in Greenvolt’s acquisition of its Bulgarian subsidiary and advised R Engineering, backed by Actis and Rezolv, on securing a EUR 90 million financing package for their St. George PV project, which is 229 megawatts. That’s one of the biggest deals in the market recently.
In hydro, we’re particularly proud of our work with Toshiba. We advised them on a major rehabilitation project for one of the units of Bulgaria’s Chaira pumped-storage hydro plant. Toshiba’s been a client of ours for nearly two decades, and this project is quite meaningful – it’s about ensuring Bulgaria can balance out its growing renewable capacity.
On the disputes side, we represented MET Suvorovo Wind Park in a successful claim against the state over an old wind tax. And we’ve been advising IBEX and the regulator, EWRC, in several ongoing court and arbitration proceedings.
Another big area this past year has been battery storage. We supported a number of clients, including Aratiden, on tenders related to stand-alone and co-located battery energy storage systems, which are being funded through the EU Recovery and Resilience Facility. These projects are really starting to pick up speed.
CEELM: What’s been driving this high level of activity?
Sirleshtov: Several key factors have contributed. First, the sector has benefited from regulatory stability. The formation of a functioning government in Bulgaria has created a more predictable environment for investors. Coordination between regulatory bodies, particularly the EWRC, the transmission system operator, and the Ministry of Energy, has improved, allowing project development timelines to accelerate.
Second, EU funding, especially under the Recovery and Resilience Facility, has created significant opportunities in energy infrastructure, most notably in energy storage, where funding mechanisms are time-bound and implementation is urgent.
Finally, investor interest remains strong. Major players in oil and gas, renewables, and equipment supply continue to enter or expand in Bulgaria. Shell, OMV, Greenvolt, Actis/Rezolv, and Toshiba are among the companies committing to new or ongoing projects.
CEELM: And what’s your outlook for the next 12 months?
Sirleshtov: The next year will likely be even more active. A key driver is the installation of more than 10 gigawatt-hours of battery energy storage capacity – stand-alone and co-located – which needs to be completed by the first quarter of 2026 under the terms of the EU-funded programs. This will be a critical period for procurement, permitting, and contracting. We also expect 2 to 3 gigawatt-peak of photovoltaic projects currently under development to move into construction, with related financings, M&A, and EPC agreements to follow.
In oil and gas, an offshore discovery would be a game-changer for Bulgaria’s energy mix. There’s cautious optimism in that direction, depending on the outcome of exploration campaigns in the Han Asparuh and Han Tervel blocks.
At the same time, Bulgaria’s renewable market is maturing. We’re likely to see more consolidation, more structured project finance, and the entry of institutional investors looking for scale. Regulatory litigation, particularly involving historical policy issues and compliance disputes, will also continue.
