Hi
I would like to do the energy modelling using option2 to achieve maximum points. In this case, base case will be modelled with Packaged Terminal Air conditioner (As the residential building). For proposed case i would like to use the default efficiency of 4.4 COP to evaluate chilled water cost based on the utility rate. Please confirm whether using default efficiency of 4.4 COP instead of virtual plant average efficiency will be accepted?
Other query is if i am modeling using option1, then 4 pipe fan coil needs to be modeled for base case. In this case the whether the fan power could be modeled with 0.00094 bhp/cfm as per Ashrae table G3.1.2.9.
Regards
Ramesh Narayanan
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5912 thumbs up
November 6, 2012 - 10:58 am
2.4.1.2.3 Default Efficiencies in the DES clearly allows the use of this default value in lieu of the actual efficiency.
No that fan power value is for a system 3 or 4. In your case it is still a system 1 and follows the fan power calculation - Pfan = CFMS ⋅ 0.3