Beating Transformer Losses

Around three percent of all energy generated in Europe is lost by distribution transformers. That adds up to 93TWH of annual energy waste. Network losses in the UK alone are responsible for 1.5% of the country's greenhouse gas emissions.

This is an issue that needs a solution. The European Commission has introduced Ecodesign Regulations for transformer losses, so that improved models can be installed all over the UK and the rest of Europe. Tier 1 and Tier 2 of these regulations came into force in 2015 and 2021 respectively.

Losses in transformers come in two types. No-load loses (sometimes called core losses) which are basic losses, start from the moment the transformer is switched on. They will create losses and emissions for 24 hours a day, 7 days a week. The other type of loss is load losses or winding losses, which are a product of the load on the transformer.

Conventional transformers have stacks of laminate material in their cores. Usually made from silicon steel with a crystalline structure, they are responsible for most of the losses. New designs of transformer that use carefully-cooled molten alloy steel, do not allow the crystalline structures to form. These have the advantage of being more easily magnetized. During the magnetization process, less heat is produced and there are lower losses. This results in more efficient transformers.

Modern transformers are around 15% more energy-efficient that existing ones, so replacement can save energy. Given that the average age of a distribution transformer in the UK is 63 years old, upgrading would save a significant amount of costs and greenhouse gas emissions.