I haven't been able to convince them that this isn't a good idea.

Our local roller rink has been trying to help cool the building by running a portable A/C inside their building this way all summer. How is it that none of the 20-30 people who work there know enough about basic physics to tell them that this is making the building warmer, not colder? I tried explaining it to the manager, but I'm not sure I was able to explain it clearly enough to make them realize this doesn't work. Explanation: For anyone who doesn't know, you can't remove heat from a space without giving the heat somewhere to go. This machine blows out cold air, but it does it by ejecting the heat through a vent in the top. So overall, this machine is making the building hotter, not colder, because all the electricity it uses becomes waste heat that makes the building hotter. This portable A/C is intended to be placed outside of a building (or tent), with the cold air ducts going into the space, and the rest of the machine ejecting the heat outside.