Possible Cooling Energy reducer?

[Keith]

Good Morning,
I had an idea on my mind and was curious what your thoughts were. This is in regards to energy efficiency of HVAC units.

I was wondering what the plausability would be of putting radiator type cooling within the return air ducts to temper the air to a lower temperature to decrease the amount of work that the HVAC units have to do to maintain a lower temperature more efficiently. As we know, by turning the AC on in your house when it is 85 degrees to get it to 70 degrees will take quite some time and your AC unit will run for a long period of time to do so. Would this be the case for 90+ degree air tempered to say 75-80 degrees before it hits the CRAC units to be brought down to say 65 degrees?

Obviously putting a radiant type ceiling in to temper the air would be inefficient and potentially harmful due to lack of possible return air actually hitting the duct...

Just pondering the concept...any thoughts?

--Keith

Hi Keith,
I am not sure about this but I would think it could take as much power to pre-cool the air going into the CRAC units if not more. There may be ways to do this using a cooling tower pumping cooled water through the radiators you are speaking of but that of course would depend on how cool that water could be and and what cost.

In the end it is always about watts and BTUs. Good thought and I love love to see some data on something like this for sure.

Cheers

This are shocking examples of how to reduce cooling costs:

http://en.wikipedia.org/wiki/Eastgate_Centre%2C_Harare

http://en.wikipedia.org/wiki/Deep_lake_water_cooling

Possible a way for data-centers, too?

[gallant]

Check out the link below. This device can reduce the energy needed to heat or cool by 80%.
http://www.semcoinc.com/products/energyrecovery/fv/

We have found this super helpful to follow. We have done this for several customers.

[Rmgill]

It sounds to me what you're essentially proposing is increasing the surface area of the cooling surface in the airflow. More or less increasing the size of the CRAC. If you supply additional chilled water flow to these new heat sinks (radiators but in reverse) then you'll be good. But if you rob cooled water flow from your existing infrastructure, you're not doing yourself any good. Water Temperature, Flow, and pressure will affect this and how it works out.

The best example I can see of this that's practical is the Cooling Doors which are starting to appear on some of the high density rack installations. This pre-cools the hotspots and focuses cooling effect on specific areas. That's a good thing because it helps prevent re-breathing of VERY hot air from high density systems.