Many Spaniards believe leaving the air conditioner on saves money, but new expert advice challenges this habit. Jorge Morales de Labra explains why switching the AC off when not needed can actually lower your electricity bill.
Jorge Morales de Labra, an industrial engineer, has publicly challenged one of the most persistent beliefs about air conditioning use in Spanish homes: that keeping the unit running for hours is more efficient than turning it off and on as needed. According to Morales de Labra, the idea that continuous operation saves money is simply false.
As temperatures rise, air conditioning becomes a daily fixture in many Spanish households. Yet, misuse can quickly drive up electricity bills. A common question is whether it’s better to let the AC run nonstop or to switch it off once the room is cool. Morales de Labra is clear: in a typical home, there is no benefit to leaving the air conditioner on out of fear that restarting it will consume more energy.
Why Switching Off Saves
The widespread notion that air conditioners use excessive power every time they start has led many people to avoid turning them off, even when the room is already comfortable. However, modern domestic units are designed to handle frequent starts and stops efficiently, adapting to changing needs without wasting energy.
Morales de Labra explains that once a room reaches a pleasant temperature, it makes sense to turn the AC off. If the space heats up again, switching the unit back on does not result in higher costs or extra strain on the equipment. Letting the air conditioner run in an empty room or during hours when it’s not needed only increases total energy consumption—and, inevitably, the electricity bill.
The general recommendation is straightforward: use the air conditioner only when necessary and turn it off when comfort is achieved. This approach reduces the total operating time and avoids unnecessary energy use.
Different Systems, Different Rules
While this advice applies to most household air conditioners, not all climate control systems work the same way. Some water-based or high thermal inertia systems may require different management, as they take longer to reach the desired temperature. But for the standard AC units found in Spanish homes, rapid cooling and flexible operation are the norm.
Morales de Labra emphasizes that the decision should not be about keeping the unit on at all times, but about avoiding unnecessary operation. Many modern models now offer programmable timers, automatic modes, ECO functions, and even app-based controls, making it easier to match usage to real needs and further optimize energy consumption.
Recommended Temperatures and Smart Features
Another key factor in saving money is the temperature setting. Experts suggest keeping the thermostat between 24 and 26 degrees Celsius during summer. Lowering the temperature below this range can sharply increase energy use, especially if the goal is to cool the room rapidly to a much colder level.
It’s also advised to keep the difference between indoor and outdoor temperatures within 12 degrees. This helps maintain comfort without overburdening the AC unit. Activating the ECO mode, when available, can further reduce consumption by adjusting power and operation to maintain a pleasant environment efficiently.
For nighttime use, the automatic shut-off function is recommended. Programming the AC to turn off after falling asleep can improve rest and prevent unnecessary electricity use. When purchasing a new unit, choosing a model with a high energy efficiency rating may cost more upfront but can lead to significant savings over time.
As Spain faces another hot summer, Morales de Labra’s advice offers a practical way for households to stay cool without overspending. By adapting habits and making use of modern AC features, it’s possible to balance comfort and cost more effectively.
