The water doesn't need to boil. As long as there is a temperature difference between the inside of the containers and the outside air (warmer inside) you'll get condensation. Naturally the warm the better - more evaporation and warmer air can hold more water vapor.
From survival manuals a solar still can be as simple as a pit dug in the ground with a cup placed in the center, covered with a plastic sheet with a rock in the center to form a cone for the condensation to drip into the cup.
Take a look at this distiller:
Here's an animated diagram of basically the same system
Grand Hotel... always the same. People come, people go. Nothing ever happens.