Helping Helen to drive Finland’s energy transition with modernized transformers
Customer Story | 4 min read
The power transformers that once served Finland’s Hanasaari coal-fired plant, now decommissioned, are being refurbished to high eco-efficiency standards by Hitachi Energy to find a new life in Helen’s new electric boiler plant. The new plant is part of Helen’s commitment to achieving full carbon neutrality by 2030.
Challenges
Repurposing transformers for an evolving country
Helen is the largest energy utility in Finland, selling electricity, district heating, and cooling. It is committed to achieving full carbon neutrality in its energy production by 2030.
Power transformers that once powered Hanasaari, one of Finland’s largest coal-fired power plants, which ceased operations in 2023, are being repurposed to help Helen advance Finland’s journey toward carbon neutrality. The main transformers, originally crafted by Hitachi Energy (Strömberg at the time), are finding new life in Helen’s new electric boilers plant, consisting of four 50 MW electric boilers powered by fossil-free electricity.
Originally launched in 1974 amid the oil crisis, Hanasaari’s coal-fired combined heat and power (CHP) plant enabled Helsinki to expand district heating. Decades later, following its closure to move into more sustainable operations, Helen’s emissions were reduced by 40%, while the city’s carbon footprint dropped by 20%. Further emissions cuts are also expected from Helen’s upcoming electric boilers, which will replace coal-fueled operations and save an estimated 440,000 tons of carbon emissions over the next five years.
To operate Helen’s new electric boiler plant, the two main 140 MVA transformers coming from the coal plant were transported back to Hitachi Energy to be fully modernized and repurposed in the new plant.
Project data
Customer: Helen
Location: Helsinki, Finland
Application: From coal-fired power plant to Electric Boiler plant
Solutions: Transformers Life Extension
- Modernization and refurbishment of 140 MVA Power Transformers
- Components Upgrades: 110 kV oil-oil bushings
Solutions
From manufacturing to new life: 110 years as trusted transformers life cycle partner
Hitachi Energy’s transformer factory in Vaasa has been pivotal in pioneering transformer technology and enabling Finland’s electrification and decarbonization journey for over a century.
Manufactured at the factory in Vaasa in the 1970s, the two Hanasaari 140 MVA transformers returned to their birthplace for modernization by Hitachi Energy. Here, the equipment undergoes meticulous upgrades, ensuring it can continue to operate effectively for more years during its second life. Hitachi Energy’s knowledge of these legacy transformers and their complete offering of transformer life extension solutions will allow them to complete their full modernization in less than a year, respecting circularity principles and avoiding unnecessary waste.
The upgraded transformers will now use a water-cooled system instead of the old air-cooled system, where oil heated by coils cooled down as it circulated in radiators to which air was blown. After the modernization, the transformers will be cooled by water, allowing heat collected from them to be captured and fed into Helsinki's district heating network. This eco-conscious innovation transforms what was once waste heat into a new resource, bolstering Helen's dedication to comprehensive energy efficiency.
As part of the modernization of the two transformers, Hitachi Energy also executed the upgrade of components, including the supply of new 110 kV oil-oil bushings, as one of the main concerns of transformers aging and the life expectancy is the condition of the insulation system and key components like bushings, tap changers, and cooling equipment.
Benefits
Building together the sustainable grid of the future
At Hitachi Energy, we put our customers at the heart of everything we do. Leveraging decades of expertise, we design transformers that not only withstand the toughest conditions but also align with today’s ambitious sustainability goals. Whether supporting renewable energy projects or enhancing grid resilience, our solutions help customers create a more sustainable, reliable energy system.
Our commitment extends far beyond manufacturing. As a trusted service partner, we support our customers throughout the entire life cycle of their transformers. By extending transformer life and minimizing the need for replacements, we help customers stay on track with their sustainability goals, ensuring that their assets continue to perform effectively in a rapidly changing landscape.
With our comprehensive service offerings—including proactive maintenance, refurbishment, and upgrades—customers can reduce waste, optimize costs, and maximize the value of their investments.
Through this life cycle approach, we foster both cost-effective and environmentally responsible energy solutions that help customers like Helen lead the charge in the global energy transition, empowering them to create lasting impact in their countries and around the world.
"When executing this kind of work, we are not compromising on the efficiency performances of the transformers, but we are, on the contrary, upgrading their capabilities to make them even more eco-efficient" Antonio-Jose Marin, Product Line Manager Transformers Service, HUB Europe, Transformers Business at Hitachi Energy
We decided to repurpose the transformers for new use with the goal of extending their life by another decade. In the current market situation of transformer shortage and long delivery times, we're now set to have the modernized units in less than a year. Choosing Hitachi Energy as a partner was natural - given their deep knowledge of these transformers and extensive experience in service, no one else could have been more appropriate for such a major task.
