FAQ
What is reactive energy and why am I charged for it in Spain?
Reactive energy is produced by motors, transformers and other equipment with coils: it does no useful work, but it flows through the installation and the grid. It is penalised on business electricity bills when the power factor (cos phi) is low. A capacitor bank removes it, at 1,500 to 6,000 euros depending on its size.
What reactive energy is, without the jargon
In short, reactive energy (energía reactiva, shown as “reactiva” on Spanish bills) is what motors, transformers, compressors and some old light fittings need to create their magnetic fields. It is not turned into useful work, but it flows back and forth along the cables, loads the installation and forces more current to be carried than you actually use.
Why you are charged for it
On business electricity supplies, the bill also measures reactive energy. When the ratio between useful (active) energy and total energy is low, that is, when the power factor or cos phi drops, a surcharge appears. It is common in:
- Warehouses with motors, compressors or pumps.
- Workshops and joineries with machinery.
- Cold stores and bakeries.
- Premises with lots of old fluorescent lighting with ballasts.
This item does not appear on normal household bills.
How to tell if you are paying it
Look on your bill for a reactive energy item or a power factor surcharge. If it appears month after month, you are paying for something that has a technical fix.
The solution: a capacitor bank
A capacitor bank is installed next to the main switchboard and compensates the reactive energy at source, automatically and in steps depending on the machinery running. Its installation follows ITC-BT-43 of Spain’s low voltage regulations.
| Item | Guide price |
|---|---|
| Capacitor bank installed | 1,500 to 6,000 euros, depending on its kVAr rating |
| Prior study with a power analyser | 250 to 600 euros |
If the surcharge is high and constant, the bank pays for itself with what you stop being charged; it has to be calculated with your real consumption.
Before installing it
- Review several bills to see how much reactive energy you pay for.
- Measure the installation with a power analyser: as well as reactive energy, it detects harmonics that can damage the capacitors.
- Size the bank in kVAr.
- Maintain it: capacitors age and need checking.
When to call an electrician
Call if a reactive energy surcharge appears on your bill. In Seville, Spain, we solve it with power factor correction and, for a full analysis of your business’s consumption, an energy audit.
Related services
Capacitors and reactive energy
We install power factor correction in Seville, Spain with a capacitor bank, so you stop paying the reactive energy surcharge that appears on the bills of many warehouses, workshops, hotels and shops. We measure with a power quality analyser, size the bank in kVAr and leave it adjusted so the penalty disappears.
Energy audit
We carry out a business energy audit in Seville, Spain: we measure consumption, find where the energy goes and propose LED, controls, solar self-consumption, reactive power compensation and power adjustment, each measure with its cost, saving and payback period. We also arrange energy performance certificates for homes.
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Need an electrician in Seville, Spain?
Call us or send a WhatsApp message with a photo of the job. You get a fixed quote before any work starts.