Transformer for a pylon

Shell Diala Transformer Oils

3D Model of Transformer

Shell Diala

Enhance your transformer operations without compromise

Improve the efficiency and sustainability of your transformer operations while reducing total cost of ownership with the Shell Diala range of transformer oils that protect your equipment and keep it running smoothly throughout its lifetime.

Shell Diala represents a range of high-performance transformer oils, including fluids based on gas-to-liquid (GTL) technology, that helps you to contribute to meeting the growing global demand for energy. Offering enhanced protection, longer oil life and greater system efficiency, they maximise equipment performance to overcome challenges like increased loads and higher voltages.

Shell Diala can also help you to demonstrate your sustainability credentials while meeting your regulatory responsibilities.

Key Benefits¹

  • Enhanced Protection

    Enhanced Protection

    Extend the operational lifetime of your transformers with a range of oils designed to keep your components in service for longer.

  • Longer oil life

    Longer oil life

    Extend oil drain intervals to maximise the potential of your equipment and keep it running at peak productivity with longer oil life.

  • Exceptional performance

    Exceptional performance

    Provide excellent protection for your transformers under higher loads and across a wide range of operating temperatures.

  •  Resistance to corrosion

    Resistance to corrosion

    Eliminate the risk of oil-related copper corrosion from sulphur build-up with transformer oils that are effectively sulphur free.

  • Consistent reliability

    Consistent reliability

    Avoid unplanned downtime to maintain the reliability and efficiency of your operations with the best possible protection for all applications.

  • Operational Simplicity

    Operational Simplicity

    Choose the right transformer oils with confidence, from a range of fluids designed to match your specific needs.

2 builders in hardhats staring at a laptop

Transformer oils and GTL technology

Oils based on gas-to-liquid (GTL) technology provide an effective choice of lubrication for use with electrical equipment – from distribution transformers to high-voltage, direct current transformers.

GTL transformer oils – such as Shell Diala S4 ZX-I, Shell Diala S4 ZX-IG and Shell Diala S5 BD – offer some clear improvements over conventional mineral-based products. As well as helping to enhance the protection of your transformer components, they can increase the efficiency of your equipment – including in low-temperature conditions.

Transformer oils based on GTL technology also provide you with consistent performance, helping you to increase the reliability of your equipment. Plus, they are simple to introduce to your lubrication systems due to their compatibility with most conventional transformer oils.

*Shell Diala S4 ZX-IG and Shell Diala S5 BD is now available only at EU/US

Pylon in a field with crops

Demonstrate your sustainability credentials with Shell Diala S5 BD

As electricity demand continues to grow, power generation is expanding into diverse and often ecologically sensitive locations. Making sure that your transformers on these sites have a high standard of environmental protection is critical.

A key element of this is biodegradability. From offshore wind to solar farms in the desert, it is important to protect the surrounding natural environment – and reduce the impact of unexpected leaks.

Shell Diala S5 BD is designed to be a high-performance, readily biodegradable oil that gives you peace of mind in operations where performance and environmental impact are both critical priorities. Meeting, and exceeding, industry-standard tests, it helps you to drive the efficiency of your operations while also demonstrating your sustainable credentials.

*Shell Diala S5 BD is now available only at EU/US

Pylon in a dusk sky

A step closer to a sustainable transformer

By enabling equipment to handle harsh, cold climates and new environmental needs, Shell Diala S5 BD supports transformer operators in overcoming the biggest challenges they currently face.

Shell Diala S5 BD was successfully tested by Siemens Energy for TenneT’s transformer substation in Schwandorf – currently the biggest three-phase TenneT grid transformer in Germany.

Download press release for more information

Make a positive impact with Shell Diala S5 BD

  • Transformer oil brochure with Pylon in the middle

    Drive performance and sustainability

    Find out how you can meet growing demand for energy without compromising on sustainability by using Shell Diala S5 BD.

    Download Shell Diala S5 BD infographic

  • Transformer oil brochure with Solar panels at the bottom

    Protect environmentally sensitive locations

    Explore the positive difference a high-performance, readily biodegradable transformer oil can make to your environmental impact.

    Download Shell Diala S5 BD infographic

  • Transformer oil brochure with transformer at the bottom

    Improve cold temperature performance

    See how to overcome the challenges of operating in extreme low temperatures with lubrication that works in the harshest conditions.

    Download Shell Diala S5 BD infographic

*Shell Diala S5 BD is now available only at EU/US

Explore the Shell Diala range

Download our brochure to find out how the Shell Diala range of transformer oils can improve your operational efficiency while reducing costs.

Download product range brochure

Success Stories

  • Brochure with Builder wearing a hardhat

    Reducing equipment costs in Germany

    Discover how a German manufacturer was able to save $250,000 through optimisation enabled by Shell Diala.

    Download our case study

  • Brochure with Builder wearing a hardhat

    Driving low-temperature performance in China

    See how Shell Diala improved reliability and reduced transformer operating costs by 68% for one energy company.

    Download our case study


1All data shown is derived from tests in laboratories at Shell Lubricant Solutions or partners using accepted standard methods.

*Shell Diala S4 ZX-I, Shell Diala S4 ZX-IG & Shell Diala S5 BD meet or exceed the specification of IEC60296 Ed5 (2020). For more product specific information, please visit for more details.


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