[Bldg-sim] eQuest/DOE2 instantaneous loads

[Ery Djunaedy]

Joe,

I am willing to repeat the "complicated and convoluted" process of
defining "component loads" in EPlus. The peak load information that
we have in DOE2 is too important for the design process, that I
really need to have similar information in EPlus.

Is there any documentation/publication that came out of the DOE
project you were talking about? Anything at all that you can share?

Thanks,

Ery

On Mon, 05 Oct 2009, Joe Huang wrote:

> Erik,
> 
> I don't agree with your assumption that going to a heat balance model
> will "make life easier" for James' needs. From my experience, getting
> the "component loads" from EnergyPlus is even more difficult than with
> DOE-2.  About 8 years ago, there was a DOE project that tried to extract
> component loads from EnergyPlus that found the task quite complicated
> and convoluted.
> 
> In the final analysis, a "component load" is an abstraction,
> since the HVAC system is responding to zone-level heat gains or losses
> that have built up over many hours.  For example, when the air
> conditioner kicks
> on in the midmorning, is that "load" due to the solar through the windows,
> the lights that came on, or the fresh air supplied over the past three
> hours?
> On the flip side, when the heating comes on at night in the Fall, is that
> "load" attributable only to the cumulative envelope heat losses and how
> should it be offset by solar heat gain and internal loads built up during
> the day?
> 
> These are bookkeeping problems that extend beyond simply switching to
> a heat balance model.
> 
> Joe Huang
> White Box Technologies
> 346 Rheem Blvd. Suite 108D
> Moraga CA 94556
> 
> 
> Erik Olsen wrote:
> >   James, this is a good illustration of the limitations of DOE2.  The 
> > input won't be as easy, but life may be easier (and more accurate) in 
> > this case if you switch to a simulation engine that includes a true heat 
> > balance model (EnergyPlus, TRNSYS, ESP-r).  These are more frequently 
> > used for investigations of dynamic building physics.
> > 
> > Regards,
> > Erik
> > 
> > Erik Olsen, PE
> > 212 219 2255 | olsen at transsolar.com <mailto:olsen at transsolar.com>
> > Transsolar Inc. | 134 Spring St. Suite 601 | New York, NY 10012
> > 
> > Transsolar Climate Engineering
> > Technical consulting for energy efficiency and environmental quality in 
> > buildings
> > New York - Stuttgart - Munich
> > 
> >