My suggestion is to make Heat Vents 5 times as effective, IF PLACED IN A REACTOR WITH 0 HEAT PRODUCTION. This would apply to all heat vents, and would make it worth your while to create cooling towers. Of course, if you find five times as effective overpowered, just suggest a lower value.
EDIT: Remember to rate, whether you like it or not.
EDIT2: Fixed a grammar fail in EDIT1.