2 Building Permits for Winnebago, MN View All ; In 2007, the city of Winnebago, MN issued 2 building permits. All permits issued were for Single Family Homes. All permits issued were for Single Family Homes. In 2006, the city of Winnebago, MN issued 3 building permits. All permits issued were for Single Family Homes.
The amount of time you have to wait depends on the weather. 1  If there are only little clouds in the sky, it takes 6 hours. 2  If there are about 50% or more clouds, you have to expose the bottles for 2 days to the sunlight. 3  If it is raining all time, this method doesn't work.
Ultraviolet light is the radiation from the sun that causes a sunburn when you have been outside too long on a sunny day. But, watch out! You can't see ultra-violet light, so you can still get sunburned on a cloudy day. The range for ultraviolet light is 10-8 to 10-10 meters.