Note: Do not assume these values to be LAWS. They are only typical values, which SHOULD BE VERIFIED for each application. Also, if you’re interested in learning even more, here’s a free download for you: Standardized EMCS Energy Savings Calculations (20.3MB PDF)
General Information
Air Movement | 6 ACH | |
1 CFM/ft2 | ||
Ventilation Rate | 5 CFM/person | |
Fan Energy | 1000-1500 CFM/hp | |
Electric Motors | 0.75 kW/hp | |
Lighting | T12s: 1.2 W/SQFT
T8s: 0.8 W/SQFT LEDs: 0.4 W/SQFT LEDs use 50% of CFLs |
|
Chiller Size | 300-600 ft2/ton | |
Ton | 12,000 BTU/ton | |
Chilled Water | 2.4 GPM/ton (10° rise) | |
Condenser Water | 3 GPM/ton (10° rise) | |
Chiller Input | Air Cooled Chillers: 1 kW/ton
Water Cooled Chillers: 0.6 kW/ton Most Efficient Water Cooled Chillers: 0.35 kW/ton |
|
Chillers & Pumps & Towers | .9-1.0 kW/ton | |
Absorbers | 18 lbs steam/ton | |
Boiler Horsepower | 33,479 BTU/hr = 9.8 kW | |
Rebuilt Systems Design | 55°F supply air | |
30°-40° rise reheat coils | ||
Dual Duct & Multizone Design | 55° cold deck | |
70-105° hot deck – with ODA Reset Schedule | ||
VAV | 55°F cooling | |
10% box leakage flow | ||
40-50% minimum fan volume | ||
People Load | 450 BTU/person/hr | |
People Density | Office | 140 ft2/person |
Theater | 14 ft2/person | |
Heat Transmission | See ASHRAE Handbook of Fundamentals | |
Glass | 1 Btu/hr°F-Ft2 | |
Good Wall | 0.1 Btu/hr°F-Ft2 | |
Masonry Wall | 0.15-0.3 Btu/hr°F-Ft2 | |
Thin Poor Wall | 0.25-0.5 Btu/hr°F-Ft2 | |
Overall Building | 0.15-0.5 Btu/hr°F-Ft2 | |
Infiltration | 0.5-1.5 ACH without Building Pressurization |
Chiller Efficiencies
EER | COP | kW/ton | |
Air-cooled (including condenser power > 150 tons) |
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ASHRAE Standard 90.1 1999 | 9.6 | 2.8 | 1.26 |
Good | 9.9 | 2.9 | 1.21 |
Best | 10.6 | 3.1 | 1.13 |
Water-cooled (>300 ton centrifugal compressor) |
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ASHRAE Standard 90.1 1999 | 16.7 | 4.9 | 0.72 |
Good | 18.5 | 5.4 | 0.65 |
Best | 26.7 | 7.8 | 0.45 |