[Bldg-sim] A Question about chilled water usage

[Sami, Vikram]

I'm looking at utility data for a building on a college campus that has a central utility plant. They list cooling energy in ton-hrs and It seems really high for all buildings across the board.

However - if you assume that ton-hrs is the metered chilled water usage and not the chiller energy, its not that bad. For example if the chilled water usage is 1 ton-hrs, that's 12,000 BTU's of cooling energy delivered. However, if whats being measured is chilled water usage (and not chiller energy), then 1 ton-hr is not the energy consumed by the chiller - that should be 12,000BTU/COP of the chiller. So if the chiller COP is 4 - then that's only 3,000 BTU's of energy consumed to deliver that ton-hr.

So - to get to the point - does anyone know if campuses monitor their chilled water usage (in ton-hrs) as chiller energy or cooling delivered?

(I hope this makes snese)

Vikram Sami, LEED AP
Sustainable Design Analyst
1382 Peachtree St. NE, Atlanta, GA 30309
t: 404-443-7462    f: 404.892.5823       e: vikram.sami at perkinswill.com   www.perkinswill.com<http://www.perkinswill.com/>
Perkins+Will.  Ideas + buildings that honor the broader goals of society
[cid:image003.jpg at 01CB5104.6CB918E0]Years of Design Innovation
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