Why does water and alcohol work so well?
Rubbing alcohol has a much lower freezing point than water (128 degrees Fahrenheit below 0), therefore it speeds up the melting process and prevents the surface from icing up in the future.
Another solution is to use kitty litter on your dashboard.
It sounds weird, isn’t it?
If you fill up a sock with kitty litter and put it in your car, it will suck up any moisture and prevent frost from collecting on your windshield.