Condensate meters

Andrea. It depends! Ok, here's a question...where is the condensate coming from. If it's out of a 'de-humidification plant (AHU, cooler, etc) then there is a possibility of using it. (I'd check weather the AHU you're pulling from is using any chemical suppresents for Legionella, etc, will that chemical be compatible with the standard cooling tower chemicals?), but to all intents as the reference guide quotes "...Condensate water" (page 22, option 2). Obviously you must have a lot of condensate to be considering this option as the threshold is 50% of total makeup water. To successfully meter the condensate you'd have to put a meter in-line and show over the performance period that the condensate was equal to 50% of the total water going to the cooling tower makeup. (compare the two meter reads and subtract) The problem with NOT metering it is that over the course of a season the amount of top up water used by the cooling tower will vary depending on the cooling demand, therefore it would be a guess as to how much condensate was actually being used. Lastly, the direct connection of cooling tower makeup water with a condensate water line will probably be illegal without air gaps and backflow preventers in the system.

The wording for non-potable water reclamation is "encouraged" metering -- I think you should be allowed to recover the condensate (I'm assuming from AHU cooling coils) and use it to displace potable water used in the cooling tower make-up which would be metered separately. If you did decide to meter it, you probably would have to use a strategy as Barry alludes to where: 1) The potable and recovered water are combined in a separate tank, and then metered as it is supplied to the tower. But that sounds like a dispropotionate effort to the quantity of water recovered unless you are in a really humid location. 2) The potable water is metered at the collection location and then added to the cooling tower as it is generated through a separate filling process -- after all the tower must be running while the AHUs are dehumidifying -- and then the potable make-up would be used to supplement. (Metered separately.) You may want to perform some psychrometric calculations before investing in the extra metering, to see what the expected quantity of recovered water will be. To make a long story short, my answer to Q #2 is that I don't know anyone doing this that meters it.