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[EnergyPlus_Support] Re: Problem with Peak results in Summary Reports: a suggestion

Thanks Jean for your answer.

You are right in pointing out the limitation of using TMY data (although simulation weather file may not be typical, it depends on the source) for equipment sizing. However, DesignDays sometimes are not adequate specially when solar radiation is relevant and the building may have differently oriented zones.

Also, energy efficient designs often admit some disconfort moments with a more adjusted equipment size (or taking into consideration elements as heat recovery, which E+ sizing does not consider) and often annual simulation is used in the process, also to estimate equipment sizes.

I understand what you mean but I also think that simulation can be useful for efficient sizing if the designer is aware of the "non extreme quality" (sorry for my english) of the weather file.

Regards,

Germán.

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "Jean marais" <jeannieboef@...> wrote:
>
> My mistake. This may be in interesting output that you request. But don't use the TMY data for equipment sizing. The concept of TMY is a) to test your equipment sizes and b) to reflect average yearly loads on the building. 
> 
> For sizing the statistical worstcase days are better as real yearly weather worstcasedays vary greatly from year to year. The TMY year's worstcasedays may be worse or beter than the statistical design days used for sizing. 
> 
> As a workaround to get the output you want in the mean time, you could do a custum period sizing run using the entire year to find the worstcase peaks of the tMY and then see what the equipment was sized to. Or spreadsheet manipulation.  
> 
> --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "ecoeficientees" <ecoeficiente@> wrote:
> >
> > Sorry Jean but peak values in summary reports come from Simulation results, not sizing results. I know the option for load averaging but it is only available for sizing calculation so it does not solve the problem of simulation peak values in Summary Reports.
> > 
> > Germán
> > 
> > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "Jean marais" <jeannieboef@> wrote:
> > >
> > > 
> > > This is implimented in the sizing:parameters object. It is the last field, Load Averaging Window Time. See the io ref as it is time step length dependant, not time dependant directly. 
> > > 
> > > Jean
> > > --- In EnergyPlus_Support@xxxxxxxxxxxxxxx, "ecoeficientees" <ecoeficiente@> wrote:
> > > >
> > > > I have found that peak values in Summary Reports, which could be useful for HVAC design can lead to extremely high values usually due to system startups (e.g.after an unoccupied weekend) and the fact that the results come from system timestep.
> > > > 
> > > > I think it could be useful to be able to setup a time window for the peak values (to average them) so that Summary Reports could be more useful for HVAC design (when the designer is interested in peak values from simulation, not from designday sizing).
> > > > 
> > > > Just an idea for E+ developers...
> > > > 
> > > > Regards,
> > > > 
> > > > Germán.
> > > >
> > >
> >
>




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