Re: [EnergyPlus_Support] Re: Heating/Cooling Changes Drastically with Occupancy

Michael

2012/8/5 Niraj Poudel <nirajpoudel@xxxxxxxxx>

Hello Michael,

Thank you for you taking the time to look into this. I am more confused as to why the heating load and cooling load changes so incredibly much, when I only add one person to the whole building. Especially when 1 person "emits" only 120 Watts (120 J/s).

I am not quite concerned about the total magnitude of the heating and cooling load but am definitely concerned about how drastically it changes with the addition of just one person in the building?

Does the decrease in heating load seems reasonable (per additional person)?

Thank you again for looking into this.

Sincerely yours'
Niraj

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, Michael Knudsen <michael.dahl.knudsen@...> wrote:
>
> Hello Niraj,
>
> It depends on how much heat is transferred through your wall and windows
> and also how much heat is coming from the sun through the window. Actually
> I dont think the increase in energy are to extreme taking into account that
> your zone has no infiltration or ventilation.
>
> Best regards
> Michael
>
> 2012/8/5 Niraj Poudel <nirajpdl@...>
>
> > **

> >
> >
> > Dear all,
> >
> > I have modeled a very simple one zone building in Eplus Version 7.1:
> >
> > a) 1225 sq ft.
> > b) 15% glazing window/wall ratio.
> > c) No infiltration, No ventilation, No Lights, No Equipment.
> > d) Heatbalance algorithm - Conduction Finite Difference with 60 timesteps
> > per hour.
> > e) HVAC - Ideal Air Loads System - always ON. (Heating Setpoint: 21 Degree
> > Centigrade and Cooling Setpoint: 25 Degree Centigrade)
> > f) Heating and Cooling Availability always ON.
> >
> > Okay now here is the problem:
> >
> > When the number of people progressively increases in the building the
> > annual heating and cooling energy changes drastically (more than expected) :
> >
> > *Zero People:*

> > Annual Heating: 1.4969E+10 Joules
> > Annual Cooling: 4.064E+9 Joules
> >
> > *1 Person (Activity Schedule is always on and the activity level is 120
> > Watts per person):*

> >
> > Annual Heating: 1.3882E+10 Joules
> > Annual Cooling: 5.303E+9 Joules
> >
> > *2 People (Activity Schedule is always on and the activity level is 120
> > Watts per person):*

> >
> > Annual Heating: 1.2853E+10 Joules
> > Annual Cooling: 6.509E+9 Joules
> >
> > Could anyone help me pinpoint what is going on here. I would appreciate
> > any insight on this issue. Thanking you.
> >
> > Sincerely yours'
> > Niraj
> >
> > --
> > Niraj Poudel, Architectural Engineer.
> > PhD student, PDBE Program.
> > Clemson University, Clemson, SC.
> >
> >
> >
> >
>