Ever wonder why ethanol is the go-to ingredient for winter windscreen fluids? It's all about a phenomenon called freezing point depression. When ethanol molecules dissolve in water, they disrupt the formation of ice crystals by getting between water molecules. This prevents them from arranging into the rigid lattice structure that forms ice.
The relationship isn't linear, though. Pure ethanol freezes at –114°C, but a 50/50 mix with water doesn't freeze at –57°C—it actually freezes around –25°C due to colligative properties. To reach extreme cold protection, you need much higher alcohol concentrations. At roughly 90% ethanol, you can achieve protection down to –72°C, which is why concentrated formulations exist.
For fleet managers in Nordic regions, understanding this chemistry matters. A highly concentrated product like Winter –72 °C ethanol offers maximum flexibility—use it full-strength in extreme cold or dilute it for milder winters.
