Transformer with Shell Diala S5 BD successfully tested by Siemens Energy for Tennet Project
Shell supplied Shell Diala S5 BD, a state-of-the-art, transformer oil made from readily biodegradable base oil (as determined by OECD 301 test methods), as part of a joint project of Siemens Energy, TenneT, and Shell.
The collaboration decided to fill the power transformer for TenneT’s transformer substation in Schwandorf, Germany with Shell Diala S5 BD. The unit is currently the biggest three-phase TenneT grid transformer in Germany with a rating of 650MVA / 400kV, and the power transformer is securing the high demand of energy in the southern part of Germany.
Shell Diala S5 BD is a state-of-the-art transformer oil formulated with a sulphur-free GTL base oil that meets the criteria for ready biodegradability under OECD 301 test methods.
The Shell GTL innovation platform was established in 2010 with the successful development and market introduction of Shell Diala S4 ZX-I. Building on its proven field performance, and responding to growing demand for transformer fluids formulated with base oils that meet the criteria for ready biodegradability under OECD 301 test methods, the development of Shell Diala S5 BD was a natural next step. Shell Diala S5 BD is a high-quality inhibited transformer oil with a highly consistent composition that meets and exceeds the requirements of IEC 60296 Edition 5 (Type A). The fluid is fully miscible and compatible with conventional mineral transformer oils, facilitating top-up, replacement, and fleet standardisation. The sulphur-free GTL technology eliminates the risk of corrosion associated with corrosive sulphur while providing excellent oxidation stability, helping to extend transformer fluid service life. In addition, Shell Diala S5 BD delivers outstanding low-temperature performance, making it well suited for applications operating in extremely cold climates, including electrical infrastructure projects in arctic conditions.
The end customer, TenneT, is a leading European grid operator and manages the high- and extra-high voltage grid in the Netherlands and large parts of Germany. As the first cross-border Transmission System Operator, TenneT designs, builds, maintains, and operates 24,500 km of high-voltage electricity grid.
After a technical examination of the transformer's oil parameters, TenneT selected Shell Diala S5 BD. It offers performance aligned with the proven capabilities of Shell Diala S4 ZX-I while using base oils that meet OECD 301 criteria for ready biodegradability. TenneT sees Shell Diala S5 BD as an important step towards the next generation of transformer fluids.
- “Shell believes that product performance and application requirements can be addressed together,” said Ed van Schaik, Product Application Specialist for Shell Diala Transformer Oils. “Shell Diala S5 BD is designed for low-temperature conditions and demanding or regulated applications, helping operators address operational requirements while supporting reliable transformer performance over the equipment lifecycle.”
- “Without any compromises in terms of performance and durability, we jointly provide add value and strengthen our customer’s market appearance,” said Mate Sicenica, Sales Director of the Siemens Energy Transformer Factory Nuremberg. “On top, we take over responsibility towards our nature and society. A big thanks to Shell and TenneT for all their support and assistance during the whole project execution.”
