Bulgaria Starts Building Its First Tesla Megapack Park, One of Three in a €350 Million Programme

Bulgaria has started building its first battery park with Tesla's participation. Prime Minister Rumen Radev broke ground on 20 October 2026 in the industrial zone of Tvarditsa, in Sliven Province, with Energy Minister Iva Petrova and Innovation Minister Ivan Vasilev, according to the Ministry of Energy and the government's press office. The park is due to enter service in the second quarter of 2027.

What is being built

Battery Park Tvarditsa is the first of three projects that the Bulgarian companies Asarel Trade and Power Profit are carrying out in partnership with Tesla. The other two are planned for Stara Zagora and Veliko Tarnovo, Mediapool reports, as former energy minister Delyan Dobrev announced last month.

Five hours is long for grid storage. At 300 MWh it implies roughly 60 MW of output; that is TeslAnt's arithmetic, as the government gave no power rating. A longer duration lets a battery carry midday solar output further into the evening, which is the role Petrova described: flexibility for a grid with a rising share of renewables.

Tesla's role, and the meeting afterwards

The government has not said whether Tesla only supplies the equipment or also builds and maintains the site, as it does at Belgium's Green Turtle park. It gave no capacities or dates for the other two parks, and no value for Tvarditsa on its own.

After the ceremony, Radev and the two ministers met Tesla representatives to discuss "potential investments in Bulgaria", the government said, without giving details. Tesla registered a Bulgarian subsidiary to sell and service cars directly in April.

Radev recalled a line heard "for years" at European forums and in the European Council: that whoever succeeds in building capacity for reliable, competitive and sustainable energy storage "holds the key to the future". "I am glad that today Bulgaria confidently holds this key," he said. He also presented the project as evidence of a deepening technology partnership with the United States.

How it compares

Bulgaria is not new to grid batteries. Petrova said the country had put more than 6 GW of storage into service in under a year and a half, which helped supply neighbouring countries during the summer. What is new is Tesla's name on a Bulgarian project.

Among Tesla's European energy deals, Tvarditsa is mid-sized but concrete. The 25 GWh NatPower agreement for Italy and Britain and the roughly 3 GWh Zhero deal in Italy are framework agreements covering future projects. Green Turtle is a single 2,800 MWh site using the newer Megapack 3 and is due at the end of March 2028. Tvarditsa is smaller, uses the Megapack 2XL that Tesla already ships, and is due to start operating nine months to a year sooner.

What to watch

The next steps are the sizes and timetables for Stara Zagora and Veliko Tarnovo, and whether the government's talks with Tesla turn into a named investment. The Tvarditsa site itself is due to start operating in the second quarter of 2027.