FAQ
What is the difference between single-phase and three-phase electricity in Spain?
The difference is the number of phases. Single-phase (monofásico) uses one phase and neutral at 230 V and is what almost every home has. Three-phase (trifásico) uses three phases with 400 V between them and is for heavy loads, motors, warehouses and some homes with aerothermal heat pumps or powerful EV chargers.
Single-phase vs three-phase, explained simply
The difference between single-phase and three-phase is the way electricity reaches your home or business. In Spain a single-phase supply (monofásico) has one phase and a neutral, at 230 V. A three-phase supply (trifásico) has three phases, usually with a neutral, and 400 V between phases.
| Single-phase | Three-phase | |
|---|---|---|
| Phases | 1 plus neutral | 3, usually with neutral |
| Voltage | 230 V | 400 V between phases |
| Typical use | Flats (apartments) and most houses | Warehouses, workshops, large premises and some homes |
| EV charging | Up to 7.4 kW | 11 and 22 kW |
Advantages of three-phase
- More power, shared across three phases, and the ability to start three-phase motors.
- It is what many industrial machines, lifts (elevators) and pumps require.
- It allows 11 and 22 kW EV chargers and some large aerothermal heat pumps (aerotermia).
Drawbacks in a home
- The circuits must be balanced across the three phases. Otherwise one is overloaded and its protection trips while the others have capacity to spare.
- If one phase drops, part of the house loses power.
- Switching requires work on the individual riser cable and the fuse board, plus a new boletín (electrical certificate).
Do I need three-phase at home?
In most homes, no. Practically every house in Seville, Spain is single-phase, and to get more power it is almost always enough to increase your contracted power (potencia contratada) without changing system. Three-phase makes sense if you are installing equipment that requires it, such as a three-phase heat pump, a motor or a charger of 11 kW or more, or in very large homes. Sometimes it is the other way round: houses with three-phase they do not need are simplified to single-phase.
What switching costs
There is no established public price. The boletín paperwork for the change is quoted at around 186 euros on average, and the work is estimated at 600 to 2,000 euros depending on the length of the riser cable and the state of the fuse board.
When to call an electrician
Call if you are unsure whether to increase your power or move to three-phase, or if your three-phase installation has unbalanced phases. In Seville, Spain, we look at your case through our contracted power increase service.
Related services
Single to three-phase
A single-phase to three-phase upgrade in Seville, Spain is what you need when your home or business is going to have very large loads: an 11 kW EV charger, certain aerothermal heat pumps or machinery. We adapt the riser cable, fit a three-phase fuse board, share the circuits between the phases and handle the boletín with the distributor.
Increase contracted power
You need to increase your electricity power in Spain when the smart meter cuts everything off as soon as the air conditioning, the oven and the washing machine run together. We check what power your installation can take, upgrade the supply cable, main switch and fuse board if needed, and issue the boletín so the distributor approves the increase.
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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.