TransformerGaining Efficiency and Saving CO2

Efficiency is one of the most important characteristics of a transformer. The higher the efficiency, the fewer losses there are and the more sustainable the transformer is. Today's transformers can achieve an efficiency of 99%. This efficiency of more than 99% is so important because many transformers are in operation 24 hours a day, 7 days a week. Due to the high number of transformers in use, the aim is to achieve even higher efficiency, making installations even more sustainable and environmentally friendly.

In order to be able to calculate the efficiency, the power must first be considered. Ideally, the output power is equal to the input power, in which case there would be loss-free transmission. In principle, the efficiency/performance can be calculated as follows:

By inductive components we mean transformers, chokes and filters.

All inductive components, including transformers, suffer losses in the form of thermal heating. These losses weaken the efficiency of the inductive winding goods. Despite the high efficiency of newer transformers of up to 99% in some cases, the losses of all transformers in Central and Northern Europe average around 5.7%. This energy not only has to be made available additionally, but also costs natural resources and the production of energy generates CO₂, which has a negative impact on the climate.

One way to reduce losses is to use suitable materials that lead to fewer losses. For example, grain-orientated sheet metal for the core or flat copper with lower electrical resistance as the winding material. However, these components are associated with a higher financial outlay when purchasing. This means that during the investment phase there is a choice: cheaper and less efficient or more expensive and more efficient. It is important to note that the investment phase is only part of the life cycle costs of a product. This will be discussed in more detail later.

The CO₂ equivalent describes the relationship between losses (in watts, W) and the actual amount of CO₂ produced (in kilograms, kg) during energy generation. The following example calculation illustrates the topic further. According to IWR/ 2013, one kilowatt hour of electricity (1kWh) generated in Switzerland, Northern and Western Europe corresponds to 590 grams of carbon dioxide.

To make a contribution to climate protection, it is important to use energy-efficient components. This not only makes a positive contribution to sustainability, but can also optimise life cycle costs. These are a very important aspect for energy-intensive goods, as they save you considerable costs over the entire service life. This is also a major issue for inductive winding goods such as transformers.

The efficiency of a transformer can be influenced by various factors such as the choice of material, the quality of the calculation or the precision of the manufacturing process. It is generally recognised that inductive components already have a high level of efficiency. Nevertheless, there is still room for improvement, which positively influences the energy efficiency of a product.

There are various causes of power losses in a transformer. These can be caused by copper, iron, etc. Basically, the following applies: The amount of power loss in a transformer determines its efficiency. And this is formed between the primary winding (input winding) and the secondary winding (output winding). From this it can be concluded that the resulting efficiency of a transformer can be described by the ratio between the input power of the primary winding and the output power of the secondary winding.

In purely mathematical terms, a transformer ideally has an efficiency of 100%. Unfortunately, this is not possible in reality. In every process in which energy is converted, a small proportion of it is lost as heat.

An example from everyday life to illustrate this. When the coffee machine needs energy to heat the water, some of the heat is also released into the environment. This means that all the energy used to heat the water has not only gone into heating the water, but a small part has warmed up the environment.

Now that we know that a 100% conversion of energy is not possible, the aim is to achieve the highest possible efficiency at a constant voltage and frequency with a very high output.

In general, transformers have an expected service life of 30 years or more. With increased energy efficiency, their service life can be extended and the thermal load on the surrounding components caused by transformer losses can be reduced.

The life cycle costs of a winding material are therefore excellent. In the case of particularly energy-efficient products, it is even possible to speak of a prompt payback effect. A positive side effect is that sustainable transformers can also extend the service life of the surrounding components through more careful use.

You can read a comparison between standard and sustainable transformers under "Sustainable products".

This transformer comparison clearly shows that investing in an energy-saving product pays off. The difference in costs is even greater for higher outputs.

To summarise, we can say that sustainable transformers not only enable us to save costs and gain efficiency, but also contribute to improving the global climate situation. An important responsibility that affects us all!