Projects & Applications

Sunterra RE commissions 94 MWh battery system in Bulgaria

A 47 MW battery system at Kaloyanovo has been commissioned by Sunterra RE, the first of three in a plan.

By

Tristan Rayner

Oct 02, 2025

Bulgarian renewables developer Sunterra RE has commissioned a 47 MW / 94 MWh battery energy storage system (BESS) at its Kaloyanovo solar power plant, near Plovdiv, in southern Bulgaria.

The newly operational system comprises 23 lithium iron phosphate (LFP) battery units. It was developed with BGN 31.7 million (approximately €16.2 million) in funding, supported by Bulgaria’s National Recovery and Resilience Plan (NRRP).

According to Sunterra CEO Emil Shopov, the facility “provides significant flexibility in managing energy flows and contributes to cost optimization.”

The Kaloyanovo site is one of three BESS projects for Sunterra RE with Galabovo and Karlovo making up the other two for a combined capacity of 156 MW / 312 MWh across its portfolio, with plans to further expand upon this in 2026.

In August 2025, Sunterra RE partnered with Sungrow who is supplying 1 GWh of storage for Sunterra RE’s solar parks, using its Power Titan 2.0 system. This rollout will be the second phase of Sunterra RE’s battery expansion plans.

According to Sunterra RE in a LinkedIn post, the company stated that the Kaloyanovo facility “is designed to balance the variable production of solar energy with the requirements of the electricity transmission grid ensuring predictability and stability of energy supply.”

Sunterra RE further said the the project represents the first phase of Sunterra RE’s three-stage BESS program, which includes systems at the Galabovo and Karlovo wind farms for a combined power output of 156 MW and total capacity 312 MWh.

Written by

Tristan Rayner

Tristan is an Electrical Engineer with experience in consulting and public sector works in plant procurement. He has previously been Managing Editor and Founding Editor of tech and other publications in Australia.

View author posts

This content is protected by copyright and may not be reused. If you want to cooperate with us and would like to reuse some of our content, please contact: editors@pv-magazine.com.

Policy

Global Battery Alliance launches Battery Passport pilots The Global Battery Alliance (GBA) has just launched the second wave of its Battery Passport pilots, which includes 11 pilot consortia. This second wave will establish the Minimum Viable Product of the GBA Battery Passport with a product-level ESG (Environment, Social, Governance) score.

Jun 21, 2024

Opinion & Analysis

Falling li-ion battery prices mirror solar photovoltaics trends: Is there a role for second-life batteries before recycling? Lithium-ion batteries are everywhere, powering everything from consumer electronics to electric vehicles, residential PV storage systems, and, more recently, mitigating curtailment in large-scale wind and solar power plants. EVs are driving large-scale demand for Li-ion batteries which will result in substantial volumes of spent batteries in the near future. This scenario highlights the potential for repurposing EV batteries for second-life stationary applications, which could maximise their value before recycling. However, to fully realise this opportunity, several economic, technical, and regulatory challenges must be addressed and resolved.

International Solar Energy Society

May 22, 2025

PV modules and battery storage

Tenders

Bulgaria launches renewables-plus-storage tenders Bulgarian businesses can apply for funding under two new tenders that aim to facilitate 1,425 MW of renewable energy generation capacity coupled with 350 MW of energy storage. Funding support is only offered for the storage component.

Mar 15, 2024

Renalfa BESS in Bulgaria

Projects & Applications

55 MWh battery storage system goes live in Bulgaria Billed as the largest operating battery energy storage system in Bulgaria to date, the 25 MW/55 MWh facility, developed by Austria’s Renalfa IPP, came online at the start of the month.

Jun 16, 2024

Anthony Albanese and Ed Husic

Manufacturing

Stationary storage key priority in Australia’s new National Battery Strategy The Australian government has announced its new multi-billion-dollar National Battery Strategy aiming to boost the country’s domestic battery manufacturing capabilities and critical minerals processing capacity.

May 24, 2024

Grid-scale

Sungrow to supply 1 GWh of battery storage for Sunterra RE’s solar parks in Bulgaria Sungrow is becoming a winner in Bulgaria as it secures another major supplier dear for its battery energy storage systems (BESS).

Aug 04, 2025

This website uses cookies to anonymously count visitor numbers. View our privacy policy.