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[EnergyPlus_Support] Re: need help w/ monthly gas usage results
Dear Dimos,
I took a look at the new file, and it appears that:
1) You have two air loops. Each of those has a Furnace:HeatCool. One
of the furnaces has a gas heating coil and the other has an electric coil.
2) You have a "Boiler:simple" (which is a hot water boiler) and a
"Boiler:Steam", but the only thing using either one is the Fan Coil in
Zone 1405.
3) Therefore, neither of the Furnaces will use any energy from the
Boilers because they're not using hot water or steam coils. In
addition, the Boiler:Steam will not use any gas, because it has
nothing connected to it.
4) If the Fan Coil has any load, the Boiler:Simple will provide it ...
as long as the Boiler is available and the Fan coil operates.
5) Finally, you have created a Gas Equipment object called "Boiler",
but it is not connected in any way with the heating loads, and
therefore is not useful to you.
6) I think you should:
a) Delete the "Boiler" Gas Equipment object. This is not the correct
approach for a heating load.
b) Connect the heating devices (Fan Coil or Furnace, whichever is
proper) to the Boiler:Simple or Boiler:Steam. If you use
Boiler:Steam, you'll need a Coil:Steam:AirHeating object in the
Furnace or Fan Coil.
c) Check the Fan Coil operation and confirm that it operates and also
has some heating to perform. Also check to see that the Boiler:Simple
is operating when you need it.
That's all I can figure out right now. Good luck!
--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, D T <ellinas.1984@...> wrote:
>
> Thanks for the help. I modeled the ovens using the GAS EQUIPMENT
object as well as the boiler. I did this in order to get monthly gas
usage values for one entire year for the entire faclity. They closely
matched the faclity's gas bills. For the boiler, I used the GAS
EQUIPMENT object because I had some problems using the STEAM BOILER
object in EnergyPlus.
>
> I specified all the inputs in the STEAM BOILER object yet I don't
get any monthly output results. I do not know why I am not getting any
values for the steam boiler. Do you know why this could be happening?
Also, I have yet to specify the fans for the ovens. But, I would like
to ask, under which object in the Fans category of EnergyPlus would I
use to model the fans?
>
> Thanks again for the help. I will upload my idf file.
>
> Dimos
>
> --- On Fri, 8/1/08, JV Dirkes II <jvd2pe@...> wrote:
>
> From: JV Dirkes II <jvd2pe@...>
> Subject: [EnergyPlus_Support] Re: need help w/ monthly gas usage results
> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> Date: Friday, August 1, 2008, 1:26 PM
>
>
>
>
>
>
> Dear Dimos,
>
> Here's my opinion:
> 1) Boiler:Steam sounds like a good choice. In my experience, the part
> load ratio coefficients make a big difference, so I encourage you to
> take some time to get realistic values of these coefficients for the
> boiler.
> 2) The Gas Equipment object looks suitable for an oven. Assuming that
> this is an oven type that is used for drying products or curing paint,
> the radiant fraction will be 0, the latent fraction will be 0, and the
> fraction lost will be about .20 - .25. A bakery oven will use similar
> fractions. You will have to determine the schedule of operation and
> load.
> 3) Finally, ovens often have a fan for the burner, another for exhaust
> and sometimes a fan for circulation; the energy for these fans should
> be included in your model.
>
> --- In EnergyPlus_Support@ yahoogroups. com, D T <ellinas.1984@ ...>
wrote:
> >
> > Thanks for the suggestion. Since I have never modeled boilers nor
> ovens in EnergyPlus, could you perhaps steer me toward the objects I
> would need to work with. I know that for boilers there are several
> objects. The plant I am modeling uses boilers for steam generation, so
> would I need to use the steam boiler option? Also, for the ovens, what
> object do you suggest I work with?
> >
> > Assuming I get these to work properly after modeling them, how would
> I get them to report in the ABUPS report?
> >
> > Thanks in advance for helping me with this.
> >
> > Dimos
> >
> >
> >
> > --- On Thu, 7/31/08, JV Dirkes II <jvd2pe@> wrote:
> >
> > From: JV Dirkes II <jvd2pe@>
> > Subject: [EnergyPlus_ Support] Re: need help w/ monthly gas usage
results
> > To: EnergyPlus_Support@ yahoogroups. com
> > Date: Thursday, July 31, 2008, 8:08 PM
> >
> >
> >
> >
> >
> >
> > Dear Dimos,
> >
> > The Boiler and ovens will operate on different schedules with
> > different loads and will have different part load efficiencies.
> > Therefore, I think you should model them separately, not as a combined
> > object.
> >
> > I have not modeled ovens before in E+, but I have applied them in
> > buildings. A typical oven will lose heat to the zone it occupies
> > through the oven walls, so you'll need to know the insulation value of
> > those walls and calculate that rate. The rate will vary as the oven
> > warms up and cools down, so you will need to know the operating
> schedule.
> >
> > An oven also loses heat through the stack. That is the amount which
> > should be assigned to the "Fraction Lost" field.
> >
> > --- In EnergyPlus_Support@ yahoogroups. com, D T <ellinas.1984@ ...>
> wrote:
> > >
> > > Thanks for the help. I now understand why I'm not getting values.
> > However, my ultimate goal is to obtain monthly gas usage values for
> > one boiler and 4 ovens for the facility I am modeling. Since I'm
> > trying to model a boiler and 4 ovens, could I just simply specify the
> > total power input from the boiler and ovens (in watts) under the GAS
> > EQUIPMENT object? When I did that, I got an error in my simulation. Or
> > do I need to use the boiler object and something else for the ovens?
> > I'm still struggling with trying to get gas usage values for this part
> > of my work. Any help or suggestions would be appreciated.
> > >
> > > Thank you,
> > > Dimos
> > >
> > > --- On Mon, 7/28/08, JV Dirkes II <jvd2pe@> wrote:
> > >
> > > From: JV Dirkes II <jvd2pe@>
> > > Subject: [EnergyPlus_ Support] Re: need help w/ monthly gas usage
> results
> > > To: EnergyPlus_Support@ yahoogroups. com
> > > Date: Monday, July 28, 2008, 12:48 PM
> > >
> > >
> > >
> > >
> > >
> > >
> > > Dear Dimos,
> > >
> > > I took a look at your file and I think your problem is this:
> > >
> > > 1) You have an ELECTRIC heating coil in the furnace.
> > > 2) Since the Furnace is the only heating object, and its coil uses
> > > electricity, there is no load for the Boiler:Steam.
> > > 3) Therefore, there is no gas consumption.
> > >
> > > --- In EnergyPlus_Support@ yahoogroups. com, "ellinas.1984"
> > > <ellinas.1984@ ...> wrote:
> > > >
> > > > Hello group,
> > > > The facility I am modeling has two boilers. I specified one of
them
> > > > under the boiler object in EnergyPlus just to see how it would
> run. I
> > > > also specified the gas rate schedule. However, when I run the
> > > > simulation and view the results, I get values of zero for the
> monthly
> > > > gas usages. Unlike the results from the electricity rate schedule
> > that
> > > > I specified, where it shows the monthly usage in the results,
I get
> > > > nothing for the gas. Is there anyone out there that knows how to
> help
> > > > me solve this problem?
> > > >
> > > > Thank you,
> > > > Dimos
> > > >
> > > > p.s. I uploaded my idf file. It is bakery3.idf with the subtitle
> "gas
> > > > rate usage values" under the problem submittal folder.
> > > >
> > >
> >
>
------------------------------------
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