[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [EnergyPlus_Support] electric power (watts) of PTAC



You need to identify the maximum power draw of your fan and compare that 
to your design intent.

Report these 2 report variables:

Output:Variable,*,Fan Electric Power,timestep;
Output:Variable,*,Packaged Terminal Air Conditioner Fan Part-Load 
Ratio,timestep;

and, if you are using an On/Off Fan object:
Output:Variable,*,On/Off Fan Runtime Fraction,timestep;

Maximum fan power is then roughly equal to Fan Electric Power / Packaged 
Terminal Air Conditioner Fan Part-Load Ratio or is equal to Fan Electric 
Power / On/Off Fan Runtime Fraction.

Another method is to either look for a time during the simulation when 
the PTAC is operating at full load or force the PTAC to operate at full 
load and then look at the reported fan power for that time period.

You will then need to determine if this maximum fan power is 
representative of your system.
Fan power of 900 W sounds high for a PTAC (unless it is very large), my 
AC system at 3 tons (10.5 kW) gives an estimated fan power of 0.018 W 
per W of rated capacity.

Hu,Jia wrote:
>  
> Thank you, Richard.
>  
> It is realistic then to have the HVAC consumption of 200 W per hour 
> (let's say  on average) or in the range of 200-900 W per hour 
> depending on a day, time, that is, external weather conditions.
>
-- 
Richard A. Raustad
Senior Research Engineer
Florida Solar Energy Center
University of Central Florida
1679 Clearlake Road
Cocoa, FL  32922-5703
Phone:   (321) 638-1454
Fax:     (321) 638-1439 or 1010
Visit our web site at: http://www.fsec.ucf.edu

UCF - From Promise to Prominence: Celebrating 40 Years



------------------------------------

The primary EnergyPlus web site is found at:
http://www.energyplus.gov

The group web site is:
http://groups.yahoo.com/group/EnergyPlus_Support/

Attachments are currently allowed but be mindful that not everyone has a high speed connection.  Limit attachments to small files.

EnergyPlus Documentation is searchable.  Open EPlusMainMenu.pdf under the Documentation link and press the "search" button.
Yahoo! Groups Links

<*> To visit your group on the web, go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/

<*> Your email settings:
    Individual Email | Traditional

<*> To change settings online go to:
    http://groups.yahoo.com/group/EnergyPlus_Support/join
    (Yahoo! ID required)

<*> To change settings via email:
    EnergyPlus_Support-digest@xxxxxxxxxxxxxxx 
    EnergyPlus_Support-fullfeatured@xxxxxxxxxxxxxxx

<*> To unsubscribe from this group, send an email to:
    EnergyPlus_Support-unsubscribe@xxxxxxxxxxxxxxx

<*> Your use of Yahoo! Groups is subject to:
    http://docs.yahoo.com/info/terms/