230 V networks are not specific to the Brussels region. They are in place in all regions around the country. They are a legacy from the past. In the early 20th century, with the arrival of the electrical power networks supplying three-phase alternating current, different technology choices were made. As such, Belgium went with 230V whereas France decided on 400V.
Each type of network has its benefits and drawbacks
At the time, these choices were made for technical, economic and even geographical reasons.
- The 400V network has the benefit that it generates less energy leakage due to cable heating for the same quantity of energy carried.
- On the other hand, a century ago copper and aluminium prices were such that the gains effected by cutting back on one wire (the neutral conductor) on the 230V networks were considerable.
400V in rural areas
Flanders and Wallonia have decided to progressively switch their 230V networks into 400V networks in the rural areas.This is because the cable lengths that need to be laid in these areas are significant and, consequently, so is the energy leakage.
230V in urban areas
In Brussels and other urban areas, where the network is dense and distances are short, the level of power leakage is very low. Which in turn does not warrant the kind of investment involved in such a major switchover operation. All the more so as customers’ indoor installations would need to be adapted as well.
As such, the predominance of 230V networks in Brussels is therefore a choice justified by economic and historical reasons.