Your Preferred Low-Carbon Energy Infrastructure Partner
Our vision is to become the preferred energy infrastructure partner for global investors and clean-tech pioneers. We believe in creating long-term energy value through collaboration, transparency, and sustainability. Each project is a step toward a low-carbon future, powered by trust and shared ambition.
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Neuhardenberg, GermanyPV 20 MW
December 2012
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Airport Weeze, GermanyPV 14 MW
December 2011
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Homberg, GermanyPV 7.4 MW
December 2012
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Pobeda, BulgariaPV 90 MW
December 2013
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Ucea de Sus, RomaniaPV 60 MW
December 2014
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Cherikov, BelarusPV 130 MW
December 2014
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Strážske, SlovakiaPV 1 MW
December 2013
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Tronvac,SlovakiaPV 1 MW
December 2011
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Vääksy, FinlandBESS 65 MWh + 250 MWh
December 2026
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Niederzier, GermanyPV 1.6 MW
December 2012
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Zhuhai, ChinaBESS 3.68MW/7.36MWh
December 2024 Grid-connected
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Nantong, ChinaBESS 6MW/18MWh
May 2025 Grid-connected
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Zhengzhou, ChinaBESS 45MW/133MWh
August 2024 Grid-connected
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Okajima, JapanPV 1.1MW
April 2016 Grid-connected
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Kotaki, JapanPV 1.1MW
May 2015 Grid-connected
Track Records
With over 2 GW of PV assets developed and operated across Europe, and 7 GW of solar + 1 GW of storage projects completed in China, Unisun has built a solid track record in both mature and emerging markets.
Our projects span Germany, Poland, Romania, the Netherlands, and are executed under various business models, including Build-Transfer (BT), Build-Operate-Transfer (BOT), and Joint Investment SPV Models.
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Neuhardenberg, Germany
PV 20 MW
December 2012
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Airport Weeze, Germany
PV 14 MW
December 2011
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Homberg, Germany
PV 7.4 MW
December 2012
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Pobeda, Bulgaria
PV 90 MW
December 2013
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Ucea de Sus, Romania
PV 60 MW
December 2014
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Cherikov, Belarus
PV 130 MW
December 2014
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Strážske, Slovakia
PV 1 MW
December 2013
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Tronvac,Slovakia
PV 1 MW
December 2011
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Vääksy, Finland
BESS 65 MWh + 250 MWh
December 2026
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Niederzier, Germany
PV 1.6 MW
December 2012
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Zhuhai, China
BESS 3.68MW/7.36MWh
December 2024 Grid-connected
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Nantong, China
BESS 6MW/18MWh
May 2025 Grid-connected
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Zhengzhou, China
BESS 45MW/133MWh
August 2024 Grid-connected
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Okajima, Japan
PV 1.1MW
April 2016 Grid-connected
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Kotaki, Japan
PV 1.1MW
May 2015 Grid-connected
Track Records
With over 2 GW of PV assets developed and operated across Europe, and 7 GW of solar + 1 GW of storage projects completed in China, Unisun has built a solid track record in both mature and emerging markets.
Our projects span Germany, Poland, Romania, the Netherlands, and are executed under various business models, including Build-Transfer (BT), Build-Operate-Transfer (BOT), and Joint Investment SPV Models.
Our Impact
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1.5GWPV Project
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2GWAccumulated PV Project Capacity
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12YearsRenewable Energy Industry Experience
Our Impact
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1.5GWPV Project
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2GWAccumulated PV Project Capacity
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12YearsRenewable Energy Industry Experience
Now We Focus on
We are currently focused on expanding our presence in
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DACH Region
Strong policy continuity, robust grid access, predictable permitting
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Nordic Region
Growing demand, stable governments, energy-intensive industries
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BENELUX Region
Offers early-stage investment potential, underpinned by growing storage demand and grid modernization
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Baltic Region
Promising markets with increasing investor interest
Project Introduction
The Sandels Project is a 30 MW / 60 MWh battery energy storage system (0.5C) to be connected to the Fingrid transmission network in Finland. The project is currently under construction and is targeting commercial operation by the end of 2026. It benefits from strong grid fundamentals, access to attractive frequency reserve and arbitrage revenue streams, and a supportive regulatory framework, positioning it as a high-quality and resilient energy storage asset.
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60MWhCapacity
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110kVHigh-voltage grid connection
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2026EndTarget COD
Further details regarding the project will be released shortly.
Business Models
We offer flexible business engagement models tailored to project stage and partner needs.
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Ready-to-Build (RtB) Acquisition-
Project acquisition subject to successful technical, legal, and financial Due Diligence.
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Ideal for investors seeking short-term construction engagement and fast delivery
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Pipeline Co-Development-
Collaborative early-stage development with local partners
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We contribute industrial expertise, regulatory experience, and supply chain access
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Focused on de-risking, accelerating permitting, and ensuring bankability
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Most Trusted O&M Services for Renewable Energy Across EMEA
Empowering a Sustainable Future with Unisun
Most Trusted O&M Services for Renewable Energy Across EMEA
Empowering a Sustainable Future with Unisun
Service Experience
Our engineering team has accumulated over 2.0 GWh of BESS service experience across Europe, covering markets including Germany, Belgium, the Netherlands, the United Kingdom, Finland, Italy, Hungary, the Czech Republic, Bulgaria, and Lithuania. Our service scope includes cold and hot commissioning, troubleshooting, regular and in-depth inspections, battery pack balancing, and EV power battery inspection, ensuring reliable and efficient operation across the asset lifecycle.
Service Coverage
Our Service Focus
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Meet Customer’s Needs-
Deep client needs insight + tailored solutions
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Service excellence & satisfaction focus
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Full-project reliable, high-quality support
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Safe/efficient renewable energy project operation
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Energetic Team of Professionals-
Team of experienced, skilled, and dynamic professionals with local qualifications
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Expert guidance and reliable processes delivered for every project
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Strong reputation for technical reliability and professional excellence
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Engineers with experience from leading companies such as CATL, Huawei, and Sungrow
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2 GWh of cumulative energy service experience
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Localized Expertise-
Strong local presence with proven market and regulatory insight
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On-the-ground support to streamline coordination and decision-making
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End-to-end assistance on local standards and compliance
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Access to a reliable network of local partners and suppliers
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One-Stop Service Solutions-
High-quality, one-stop energy service solutions tailored to client needs
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Comprehensive coverage: ESS commissioning, project delivery, troubleshooting, repair, and regular maintenance
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Focused on maximizing system efficiency and extending system lifespan
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Long-Term Cold and Hot Commissioning in BulgariaIn Bulgaria, we supported the client through long-term cold and hot commissioning, ensuring a high-quality system delivery within the required timeline. Our team worked closely with local stakeholders and the client’s technical teams to manage testing, optimisation, and issue resolution across multiple commissioning phases. Through structured processes and on-site expertise, we helped secure stable performance, regulatory readiness, and timely commercial operation.
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Battery Pack Replacement in FinlandIn Finland, our team successfully delivered a full battery pack replacement project under extreme winter conditions. Leveraging strong local resource networks, we rapidly identified and coordinated qualified suppliers, logistics providers, and site support. Despite low temperatures and challenging on-site conditions, the project was executed safely, efficiently, and on schedule—demonstrating our ability to mobilize local expertise, manage complexity, and deliver reliable outcomes even in harsh environments.
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Batch rework at multiple locations in EUWe have implemented batch rework for battery products across client-designated locations in France and Italy, alongside our own warehouse. Working in close collaboration with the client's technical and logistics departments, our team coordinated workflows encompassing control board replacement, software upgrades and configuration, functional testing, and documentation. By integrating controlled internal processes with flexible on-site operations, we ensured operational safety and consistent quality of completion.
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About Unisun
As Unisun Group’s European arm, Unisun Energy Services GmbH is committed to being Europe's leading trusted partner in Battery Energy Storage Systems and EV battery services, driving innovation, sustainability, and excellence in energy management and mobility solutions.
About Unisun
As Unisun Group’s European arm, Unisun Energy Services GmbH is committed to being Europe's leading trusted partner in Battery Energy Storage Systems and EV battery services, driving innovation, sustainability, and excellence in energy management and mobility solutions.
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2013
Unisun Energy Group was established, focusing on the investment and construction of distributed photovoltaic stations for C&I clientele. -
2017
The Group completed Series A financing, successfully building nearly 60 distributed PV stations, including the Wahaha project cluster, with a total installed capacity exceeding 300 MW. -
2020
The Group launched the "Zero-Carbon New City Initiative," partnering with large-scale power enterprises to enable more small and micro businesses to benefit from green energy. -
2023
The Group launched the "Smart Green Electricity Service Upgrade" strategy, creating a cleaner, smarter, and diversified renewable energy system for clients. In the same year, the Group completed Series C financing. -
2024
The Group established an European subsidiary – Unisun Energy Services GmbH, supporting European clients in green energy transition through project development, construction, after-sales, and O&M.
Strategic Partners
We collaborate with a broad network of partners—including technology leaders, institutional investors, and local governments. These partnerships enhance our execution strength and broaden our development capabilities across multiple countries.
Together With Us, Moving Purposefully Towards Climate Neutrality...
We welcome inquiries from all stakeholders interested in shaping the future of energy.
