The journey of a 300 tonne transformer

Our Contracts and Logistics Manager, Jose Lopez, had a task on his hands when faced with transporting a 300 tonne transformer 2,850 miles across Europe from Croatia to Spain. Here he talks us through that journey. 


A transformer fit for purpose 

Talayuela Solar in Spain is one of the largest solar energy projects in Europe. At 300MWp (and almost one million solar PV panels), it will generate approximately 600GWh/year. Without doubt, a project of these characteristics requires a large transformer that’s capable of raising the generation voltage of the electricity from the solar from 30,000V to the required voltage for the electrical network, of 400,000V.  

At the beginning of 2019 we began to research and have conversations with suppliers of transformers. In the middle of the year we signed a contract with Siemens España. The transformer required a long manufacturing period and plenty of testing, so it was purchased before the EPC-build contract for the Talayuela project had been signed. A risk worth taking. 

It is one of the largest transformers in Spain, weighing almost 300 tonnes. This brings great challenges not only in the logistics of an item, but also for the engineering team, who spent countless hours reviewing the technical specifications and quality standards to ensure it would be fit for purpose 

From Zagreb to Talayuela 

Once the transformer was manufactured (in Zagreb, Croatia), it was transported by train to the port of Rijeka in early 2020 where it waited for the go signal to start its journey – 6 days by ship to Spain, along the Guadalquivir river to the port of Seville.  

Meanwhile in Spain, the construction of the solar project was progressing, and the process of getting the permits for the transport of the transformer from the port of Seville to Talayuela by train had begun. This process was long and complex as the weight and specification of the transformer meant that many options and transport routes had to be considered. My main fear was that this stage could delay the construction of the solar project – but with many individuals and teams at Solarcentury involved, after multiple reroutes, an option was approved by the railway authority, AdifOur perseverance paid off and we were granted permission to have the transformer transported by rail to the railway track that runs through the Talayuela Solar project 

Finally, on the afternoon of September 4th, the transformer left the port of Seville by train on a 9 day journey to the Talayuela Solar project. This portion of the journey was meticulously planned alongside Adif so it didn’t affect the daily operations of the railway. We could only travel when there was no other traffic, at crossings and bridges our speeds were reduced to 2km/h with constant structural checks, and at one section our route diverted from the main track to a section unused for years, still with wooden sleepers – assessed as safe for the transformer.   

In the early morning of 13 September, just after the train arrived, the transformer was unloaded using temporary side tracks – specifically manufactured and installed for this purpose – and the transformer was pushed from the train onto the unloading platform, using hydraulic jacks. This was a very complex procedure as the train track had to be opened up again at specific time to allow traffic to continue along it, so this step was carried out against the clock following a specified plan with all the required safety measures followed. The unloading operation lasted about 6 hours, until the train was empty and released.  

The following day, 14th September, the workforce worked in shifts, around the clock, to load the transformer on to the SPMT multi-axle trolley (12 axles), next to the train track. This operation took 7 hours, 2 cranes, a lifting platform, and a self-propelled hydraulic lifting gantry . 

On 15th September, after 3 intensive days of work, the unloading operation was complete and first thing in the morning, the SPMT trolley took the transformer to the substation at the Talayuela site. All the health and safety measures were implemented, such as isolating high voltage lines, closing roads to traffic, controlling signals and so forthThe transformer was unloaded through the self-propelled gantry, onto rails installed in the substation which would be used to drive the transformer on its wheels to its final position.  

A job well done 

We are proud to say that the transformer was installed according to the planwithout any incident, in place and ready to complete the remainder of the Talayuela solar project with no delay. In general it has been a long and intense process, but definitely rewarding! I come away with one more great experience and many lessons learned for future such projects at Solarcentury, all alongside the positive efforts of the team.