Limiting the temperature at which our air conditioning systems work is, in essence, to implement a change in the way we consume. You lose in comfort, but you gain in energy savings. According to Laura Garcia, spokesperson for the energy commission of the College of Engineers of Catalonia, this is the key to the energy issue. “Only when we know what we consume is when we can become aware and take measures”, introduces the expert, who is also director of energy transition for the Trébol Energía Group.
This consultancy accompanied the implementation of the measures established in Royal Decree Law 14/2022 in two office buildings. In both cases, this savings goal was achieved. “In the spaces where they have been implemented, consumption has been directly affected, with a reduction of 8% in the first case and 10% in the second”, says Garcia.
However, obtaining an overall figure of how much savings this decree-law entails in Spain is complicated: it is not explained with records on what the initial situation of each establishment was, nor on the modifications that have been applied to each case . “Although there has been a change in energy demand, it is not possible to know whether it has been caused by an increase in self-consumption, a reduction in production or because these kinds of measures in energy efficiency have really worked”, he adds expert
The percentages of savings that were achieved in these buildings are those that are generally considered to be obtained when the air conditioning units are modified by 1ºC (figures that range between 5% and 10%). But, in addition to consumption, it is important to consider the technical characteristics of each device. Its influence on the level of savings is very high, as warned by José Enrique Vázquez, president of the Group of Energy Managers (GGE) of Catalonia. “If you have a fridge from 10 years ago and you buy a new fridge, the saving is 40%. It’s the same with air conditioners.” In new air conditioners, which in themselves are more efficient, these figures of 8% for 1ºC, are not so certain, but are a little lower, as Vázquez points out.
Using fans or creating cross air currents, the two lowest energy cost strategies, are some of the most economical measures to reduce the amount of the electricity bill, although they are not written in the aforementioned decree. Valencia airport, with its large ceiling fans, is a good example of this. In the same vein, it is recommended to put up awnings, curtains or lower the blinds.
Another strategy, very useful for shops and offices, would be to reduce the amount of heat inside the premises. The best example for this case are vending machines; since they give off heat when they are in operation, the most suitable option will always be to place them in rooms where there are no people working.
In structural terms, the most important thing is the insulation of the building. So much so that, in other countries of the European Union, the Administration grants subsidies to improve it. Efforts are focused first on the roofs (roofs and roofs), then on the windows (which are important to be able to open), and finally on the walls.
“Even though, without a doubt, the most effective thing would be for the roof of every building, sports center, school or town hall, to have photovoltaic panels”, concludes Vázquez. Although this measure does not imply a reduction in electricity consumption, it would lead to a reduction in bills and the environmental impact of energy.