How to keep your home cool without air conditioning

Against the backdrop of prolonged periods of abnormal heat, maintaining a comfortable temperature in homes is becoming a serious problem. In light of this, experts from the national agency Klima-Agence, Fenn Faber and Sarah Juchems (Sarah Juchems) recommend focusing first and foremost on preventing heat from entering the home, rather than relying solely on energy-intensive cooling. The perception of heat is individual and depends largely on living conditions: a top-floor flat in the city centre heats up considerably more than a country house surrounded by greenery.

The most important protective measure is to block out direct sunlight. Experts advise closing blinds and shutters, and only opening windows for ventilation during the cooler parts of the day — early in the morning or in the evening. Furthermore, high-quality thermal insulation not only protects the building from the cold in winter but also effectively keeps out the summer heat. In Luxembourg, there is a government subsidy scheme called Klimabonus, run by the Ministry of the Environment. Under this initiative, homeowners can receive between 40 and 140 euros per square metre for insulating a façade or roof, as well as an additional 15 euros per square metre if they opt for green structures.

However, traditional methods of shading and night-time ventilation may prove insufficient for buildings such as schools, hospitals and care homes. In such cases, the installation of air-conditioning systems is justified; however, their use is associated with high electricity consumption. In particular, portable air conditioners consume three to four times more energy than their fixed-installation counterparts. According to Fenn Faber, cooling three rooms with a portable unit for one week requires roughly the same amount of electricity as an average fridge consumes in a whole year. To optimise costs, Klima-Agence recommends combining fixed air-conditioning systems with solar panels, as well as using fans, which do not lower the room temperature but improve people’s physical well-being.

In addition to individual solutions, adapting to high temperatures requires systemic changes in urban planning. Experts are calling for an increase in green spaces and a reduction in the amount of tarmac. During the discussion, particular attention was paid to gravel gardens. Stones accumulate a great deal of heat and, when exposed to direct sunlight, can heat up to 40–50°C, leading to a rise in temperature both in the surrounding area and inside the building itself. It is expected that new national building regulations will ban the installation of gravel gardens. As an alternative, it is proposed to use green front gardens and façades, as plants provide shade, release moisture into the air and contribute to the natural cooling of the environment.