Southern Europeans use water bottles in windows to cool homes

In parts of Southern Europe, residents are placing containers of water, such as plastic bottles, inside window frames to lower indoor temperatures. The water absorbs solar heat, gradually drawing warmth away from the room and helping maintain a more even temperature throughout the day. The method is recommended alongside other low‑cost measures: keeping curtains closed, shutting windows during peak sun, and turning off electrical devices that generate unnecessary heat. While it does not replace air‑conditioning, the technique provides a simple way to reduce heat buildup in homes lacking cooling systems.

The approach is highlighted as an old, inexpensive solution that can be adopted quickly, especially where modern cooling infrastructure is limited.