The window (frame) surface is cold, but the air in the apartment is humid. Humid air condenses on a cold surface (when it drops below the dewpoint temperature).
So you can either make the window fram ... read more
Solar shingles are expensive and unproven. I recommend Sun Power photo voltaic solar. An average home is $20,000 to $30,000 and the return on investment is 4 to 6 years on a 25 plus year system.