Below, we take a detailed look at how the weather influences your appliances' behaviour and what tools you have at your disposal to detect every variation in your consumption.

Why does your electricity consumption change depending on the time of year?

It is not so much about the date on the calendar. What really influences an appliance's consumption as the seasons pass is the outdoor temperature, the hours of daylight and the habits that set the rhythm of your home:

Outdoor temperature

The ambient temperature is one of the most decisive factors influencing a home's energy spend. On the one hand, it dictates the use of climate control systems, such as heating or air conditioning, which demand higher power intensities to cool or heat the air. On the other hand, it is responsible for the thermal strain on refrigeration equipment. A fridge compressor, for example, has to work harder to dissipate heat when the kitchen's ambient temperature rises during the warmer months.

Hours of daylight

The need for artificial lighting inside homes changes throughout the year, depending on how much sunlight we get. During autumn and winter, night falls earlier and forces us to keep our lights on for longer. However, thanks to LED technology bulbs, which consume up to 80% less than traditional lighting, this factor has a small financial impact compared to the cost generated by thermal equipment or heating and cooling systems.

Changes in habits

Throughout the year, people adapt their routines to each season. During the colder months, we spend more time at home, which increases the use of the kitchen, the television or electricity consumption in general. Furthermore, rainy or highly humid days force us to use the tumble dryer more frequently.

Which appliances take on a greater role in each season?

Many of the appliances we have at home run continuously, 365 days a year. Others, however, are only used at certain times of the year, driving up seasonal consumption. In the following table, we look at which devices take centre stage depending on the season and which ones make up a home's baseload consumption:

Remember that just because an appliance has a high power rating does not automatically mean it is responsible for the highest annual cost on your bill: the total amount of kilowatt-hours consumed depends equally on how long it runs continuously.

Autumn: what consumption starts to rise before winter?

Autumn represents a transition period where the home's energy clock starts to tick to a different rhythm. The days get shorter, so we turn on the lights earlier and earlier. In regions where night-time temperatures drop rapidly, heating systems are turned on occasionally for the first time.

At the same time, the arrival of rain reduces the chances of drying clothes outdoors, leading to greater use of the tumble dryer. In the kitchen, the tendency is to return to stews and longer recipes, increasing how often the oven and ceramic hob are used. The key question for diagnosing this season is to identify what new consumption has started to appear on the bill compared to September.

Winter: when heating can dominate consumption

During winter, the need to keep rooms at a comfortable temperature can become the home's central energy expense, reaching up to 47% of the total.

In homes that use electric heating systems (such as heat pumps, oil-filled radiators, convector heaters or electric water heaters), this item can cause the monthly bill to skyrocket.

Although it is advisable to maintain efficient habits, such as replacing bulbs with LEDs, the financial impact of changing a light bulb is secondary compared to the impact that several hours of electric heating can have on the bill amount.

Spring: discover your home's baseload consumption

Spring offers a great opportunity for household energy management. As temperatures become milder, the need for heating almost completely disappears and the use of air conditioning is virtually non-existent.

This thermal neutrality makes it possible to determine the home's baseload consumption; in other words, the absolute minimum amount of energy your home needs. This baseload usually consists of the fridge, the freezer, the router, the cooker, the washing machine, other entertainment appliances and some devices left on standby.

Knowing exactly how many kWh this baseload consumption amounts to during the spring months allows you to establish a benchmark to compare against the seasonal peaks of summer and winter.

Summer: air conditioning and refrigeration take centre stage

When temperatures peak, air conditioning and refrigeration start to account for a large part of the electricity demand:

• Air conditioning: Its consumption is determined by the unit's power rating, the total number of hours it runs and the selected temperature. Setting the unit to excessively low temperatures causes a disproportionate increase in costs, since, according to the Institute for the Diversification and Saving of Energy (IDAE), every degree can mean a 7% difference in consumption.
• Fridge and freezer: Unlike air conditioning, the fridge runs uninterruptedly 24 hours a day. In summer, the heat in the kitchen forces the compressor to start up more frequently and run for longer cycles to keep food at the optimal temperature.
• Fans: Fans consume a much smaller fraction of electricity than compressor-based air conditioning units, making them an efficient alternative for creating a cooling sensation by circulating the air.

How to know how much each appliance costs to run

Before explaining how to calculate the running cost of any electrical equipment, we must pause to differentiate between two concepts that are often confused:

• Power (expressed in kilowatts, kW): indicates the energy the appliance needs to run.
• Energy consumption (expressed in kilowatt-hours, kWh): reflects that power multiplied by the time it is active. In other words, the amount of energy it has consumed.

The basic mathematical formula for determining a device's consumption is as follows:

Consumption (kWh) = power (kW) × usage time (h)

Subsequently, to translate that consumption into the cost on your total bill, you simply multiply it by the unit rate of your contracted tariff:

Cost = kWh × price in €/kWh

It should be noted that for appliances regulated by a thermostat or compressors (such as fridges, heat pumps or air conditioning), multiplying the maximum power by the hours elapsed only provides a theoretical maximum value. These appliances do not draw their nominal power continuously; rather, they alternate working cycles with resting periods as they reach their target temperature.

How to find out which season makes your consumption skyrocket

Analyse the actual consumption data provided by your smart meter and follow these four strategies to understand your home's efficiency:

Compare your monthly kWh

Access your reading history via your bill, the Customer Area or the Endesa Clientes app and note down the total kWh consumed in these four representative months: January (winter), April (spring), July (summer) and October (autumn). Observing the difference between the transitional months and the extreme weather months reveals the exact volume of energy that your climate control systems use.

Look for differences compared to the previous year

To assess whether a bill increase is due to a change in habits or weather conditions, compare the kWh consumed in a specific month against the same month the previous year (for example, July 2025 versus July 2026). If consumption rises significantly while temperatures remained similar, it is a sign of an efficiency fault in an appliance or a change in your household routine.

Identify which appliance started running

By cross-referencing strategic dates, such as the exact moment climate control systems (electric radiators, dehumidifiers or air conditioning) were turned on, we can attribute to each appliance its share of the increase in the bill.

Check your hourly consumption

From the Endesa Clientes app and the Customer Area, you can view your detailed hourly consumption. Analysing demand peaks in specific time slots allows you to identify which appliance was running at that moment (for example, a sudden jump in consumption at 21:00 coinciding with the oven or tumble dryer being turned on).

What is driving up your consumption? Quick diagnosis

Once you have analysed your history, identify the scenario that best describes your situation from the following points, and discover the cause of the increase in your electricity bill:

• My consumption only skyrockets in July and August: It is highly likely that the source is the air conditioning system, or the fridge and freezer working overtime due to high kitchen temperatures.
• My consumption skyrockets in December, January and February: The determining factor could be electric heating, the use of heat pumps, the electric water heater or frequent use of the tumble dryer.
• My consumption stays very high all year round: In this case, the cause appears to be a high baseload consumption: an old fridge, too many devices left on standby or inefficient use of the washing machine or dishwasher.
• My consumption is progressively increasing without any change in habits: This is a clear indicator that an appliance is suffering from wear and tear, lack of maintenance or dirt build-up (for example, blocked air filters, ice build-up in the freezer or limescale deposits on heating elements).

Frequently asked questions about consumption and seasons

In which season is the most electricity consumed?

There is no universal answer for all homes. The season with the highest consumption varies depending on the climate zone where the home is located, the type of energy used for heating (gas or electricity), the degree of thermal insulation and the climate control equipment installed. In inland areas of the Spanish Peninsula with harsh winters and electric heating, the peak occurs in winter; in warm coastal areas with intensive use of cooling systems, the peak usually occurs in summer.

Which appliances consume the most in winter?

The appliances that have the greatest impact on the bill during winter are electric heating systems, the electric water heater, the tumble dryer and, to a lesser extent, the lights, which stay on for more hours due to the lack of sunlight.

Which appliances consume the most in summer?

During the summer season, the main culprits are the air conditioning system, the fridge and the freezer, whose motors have to perform more working cycles to maintain the indoor temperature against the outdoor heat.

Does the fridge consume more in summer?

Yes. Even if the fridge's internal temperature is set the same all year round, the high temperature in the kitchen during summer makes it harder to dissipate heat from the rear grille. This forces the compressor to turn on more frequently and for longer, increasing its kWh consumption.

How can I find out which appliance consumes the most?

The most accurate way is to check the consumption graphs in your history or use individual plug-in energy monitors (wattmeters), which show the kWh consumed by an appliance in real time.

Does an appliance with more power always consume more?

Not necessarily. The final electricity consumption (kWh) depends just as much on the power (kW) as on the total time the appliance remains switched on (hours). For example, an oven has a very high power rating, but is used for few hours a month. Meanwhile, a fridge has a low power rating but runs continuously 24 hours a day, generating a higher total annual consumption.