Spanish Smart Meters Explained: ICP, Potencia and Power Cuts

What is a smart meter in Spain?

A smart meter is a digital electricity meter that records your electricity usage and sends readings remotely to your electricity distributor. In Spain, the distributor owns and manages the meter, even if you pay your bill to a different supplier.

Smart meters replaced older analogue meters with spinning discs. They allow remote meter readings, remote tariff changes, and in most domestic supplies they also replace the old physical ICP power limiter.

How to tell if you have a smart meter

Most homes in Spain now have a smart meter, especially domestic supplies below 15 kW. You can usually identify one by checking the electricity meter cabinet or communal meter room.

You probably have a smart meter if:

• The meter has a digital display instead of a spinning disc.
• It shows changing numbers or menu screens.
• There is a small flashing light showing electricity use.
• The meter has a brand such as ZIV, Landis+Gyr, Sagemcom, Circutor or similar.
• Your bills are based on real remote readings rather than estimated readings.

In apartments, the meter is often located in a shared cupboard or meter room rather than inside the home.

What did smart meters replace?

Older Spanish homes often had a separate ICP, short for Interruptor de Control de Potencia. This was a physical power limiter that would trip when the home used more power than the contracted amount.

With modern smart meters, the ICP function is usually built into the meter itself. This means the meter can disconnect the supply if the home exceeds the contracted power limit for too long.

Does a Spanish smart meter cut off instantly if you exceed your potencia?

No. A Spanish smart meter does not normally cut the electricity the instant you go slightly above your contracted power.

The meter follows a tolerance curve. A small overload can usually be tolerated for longer, while a large overload can disconnect the supply much faster.

The exact behaviour depends on the meter model, distributor configuration, duration of the overload, and the type of load being used. This is why a kettle, oven, air conditioner or pool pump may briefly push demand above the contracted power without immediately cutting the supply.

Why does the electricity trip when too many appliances are used?

If your electricity cuts off and your fuse box switches are still up, the smart meter may have disconnected the supply because the home exceeded its contracted power for too long.

Common appliance combinations that can cause this include:

• Oven plus induction hob
• Air conditioning plus electric water heater
• Pool pump plus kitchen appliances
• Electric heating plus washing machine
• EV charging plus normal household use (read our guide to EV charging and electricity tariffs in Spain)
• Sauna or high-power electric heater plus other appliances

In Spanish this is often described as “saltan los plomos”, even though the disconnection may now happen at the smart meter rather than from an old-style fuse.

How to reconnect after the smart meter cuts power

If the smart meter disconnects the supply because of excess power demand, try this:

1. 1Turn off the highest-power appliances first.
2. 2Check that the switches in your fuse box are still up.
3. 3Wait a short time.
4. 4Reset the supply if your meter or installation requires it.
5. 5Turn appliances back on gradually.

If the power does not return, or if the meter display is blank, the issue may be a fault rather than a potencia trip — read our guide to reporting an electricity fault in Spain.

What is maximum demand and why does it matter?

Maximum demand is the highest power level recorded for your supply over a period of time. It is extremely useful when deciding whether your contracted power is too high.

For example, if a home is paying for 9.2 kW but the highest recorded demand in the last year was only 5.2 kW, there may be room to reduce the contracted power safely.

However, maximum demand is not always the same as a one-second appliance spike. It is usually based on measured intervals, so a very brief surge may not appear as the maximum demand figure.

This is why a proper bill check should look at more than just the price per kWh. A cheaper tariff matters, but overpaying for contracted power can also cost hundreds of euros per year.

Should you reduce your potencia?

Many homes in Spain can reduce their contracted power, but it should be done carefully. Reducing potencia too much can cause nuisance disconnections, especially when several high-power appliances run at the same time.

A sensible reduction should consider:

• Your current contracted power
• Your highest recorded demand
• Whether you use electric heating
• Whether you have an EV charger
• Whether you use a sauna, pool pump or electric water heater
• Whether you are usually at home during peak usage times
• Whether solar or battery storage changes your grid demand

Do not reduce potencia simply by guessing. If your bill or distributor data shows your maximum demand, it is possible to make a much safer recommendation.

Do solar panels change how much potencia you need?

Solar panels can reduce the amount of electricity imported from the grid during sunny hours, but they do not always reduce the contracted power you need.

Your potencia should still cover the times when solar production is low or when several appliances run at once. This is especially important in the evening, winter, or during cloudy weather.

If you have battery storage, your grid demand may be lower, but this depends on how the battery is configured and whether it can support high-power loads. Read more in our plug-in solar in Spain guide.

Smart meters, CUPS numbers and switching supplier

Your CUPS number identifies your electricity supply point. It is not the same as your meter serial number, but it is linked to the supply address and distributor records.

When switching supplier, the new supplier uses the CUPS number to request the supply change. In some cases, the CUPS can also be used by authorised energy companies to check technical supply information such as contracted power and meter data. – learn what a CUPS number is and where to find it.