One of the most important criteria of selecting a good quality transformer is the indicator of energy losses, which come from its operation. The minimizion of the energy losses of the transformer has a direct effect not only the environmental protection and the energy footprint of the factory (or the building) where it is installed, but also at its operational cost since lower energy losses result in lower operational costs.
Therefore, an “expensive” transformer with low energy losses ends up being more cost efficient if we take into consideration that it has a lower operational cost. On the other hand, a “cheap” transformer ends up being expensive due to high energy losses leading to higher operational costs.
In the example below, it is estimated the benefit derived from a high quality transformer with lower energy losses in comparison to a transformer with higher energy losses.
According to a study and relevant measurements that were made in EMMIS Quality Control department, the non-certified transformers available in the market today have an average of 4%-7% higher energy losses.
Comparing two transformers of 500VA, we assume that the non-certified transformer with high energy losses has an efficiency factor of 87%, while the certified transformer has an efficiency factor of 92%.
The following table shows the additional energy consumption cost of an installation with (10) ten non-certified transformers with high energy losses and 500VA power.
|Power consumption difference(KW)
|Additional energy consumption(KWH)
|No of transformers
|Total additional energy consumption(KWH)
|Price per kWh *(€)
|Additional cost of energy consumption per day(€)
*According to energy costs for household use in Greece in the low-consumption scale (0-1600kWh), including adjustable charges.
The additional operational cost of the non-certified transformers with high energy losses equals 365days x 0.3048€=111.25€ per year.
The amount of 111.25€ is the annual benefit derived from the installation of certified transformers with low energy losses.
Taking into consideration the real purchasing cost of the transformers (certified and non-certified) according to present market data, the highest purchasing cost of the certified transformers is depreciated in less than (6) six months due to the energy saving achieved from the operation of certified transformers with low energy losses.
In next article, we present how the EMMIS certified transformers achieve low energy losses (up to <3%).