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Re: [EnergyPlus_Support] Re: need help w/ monthly gas usage results



Thanks for the suggestions from you and Richard. I modeled this facility using DesignBuilder and imported the idf file into EnergyPlus. In the model, I have DX cooling  along with split system/gas furnace for heating in the office area.  The largest zone (zone 1405) has no heating. It only uses mechanical ventilation and outside air. The hot water boiler was added in there from DesignBuilder for the gas furnace in the office area. If I'm correct, I don't think that zone I designated as the offices is being heated.
 
I deleted the Furnace:heating object because I don't need to heat zone 1405 with the either the steam boiler nor the hot water boiler. Rather, the steam from the steam boiler is being used for a process in the zone.
 
I tried connecting the appropriate branches and/or coils to the steam boiler, but I'm still having problems. Though the errors aren't fatal, I am still not getting gas usage values from the steam boiler. I'm having problems with node connections for the steam boilers. Something is not correct and, despite the error messages, I still cannot figure out how to correct it.
 
Any help or suggestions as to how I can fix this problem are appreciated.
 
Thanks,
Dimos
 


--- On Wed, 8/6/08, JV Dirkes II <jvd2pe@xxxxxxx> wrote:
From: JV Dirkes II <jvd2pe@xxxxxxx>
Subject: [EnergyPlus_Support] Re: need help w/ monthly gas usage results
To: EnergyPlus_Support@xxxxxxxxxxxxxxx
Date: Wednesday, August 6, 2008, 9:05 PM

Dear Dimos,

In addition to Richard's comments, I suggest....

I'm not sure why you are trying to use both hot water AND steam
boilers on the same building, but consider these suggestions. ..

1) Use a fan coil with hot water heating for Zone 1405 and delete the
furnace. You can get both heating and cooling from that single object
and ignore the Steam Boiler completely.
2) If you need to provide outdoor air to zone 1405, and it must use
heat from the boiler, you'll have to abandon the Furnace and instead
create an air handler with OA mixer, cooling coil and heating coil.
The Branch will look something like...

BRANCH,
Branch_AirLoop_ AH1, !- Branch Name
Autosize, !- Maximum Branch Flow Rate {m3/s}
OUTSIDE AIR SYSTEM, !- Comp1 Type
OASystem_AH1, !- Comp1 Name
NodeOut_RFan_ AH1, !- Comp1 Inlet Node Name
NodeOut_MA_AH1, !- Comp1 Outlet Node Name
PASSIVE, !- Comp1 Branch Control Type
DXSystem:AirLoop, !- Comp2 Type
DXAirLoop_AH1, !- Comp2 Name
NodeOut_MA_AH1, !- Comp2 Inlet Node Name
NodeOut_ClgCoilAir_ AH1, !- Comp2 Outlet Node Name
PASSIVE, !- Comp2 Branch Control Type
FAN:SIMPLE:VARIABLE VOLUME, !- Comp3 Type
SFan_AH1, !- Comp3 Name
NodeOut_ClgCoilAir_ AH1, !- Comp3 Inlet Node Name
NodeOut_SF_AH1, !- Comp3 Outlet Node Name
ACTIVE, !- Comp3 Branch Control Type
COIL:WATER:SIMPLEHE ATING,!- Comp4 Type
HtgCoil_AH1, !- Comp4 Name
NodeOut_SF_AH1, !- Comp4 Inlet Node Name
NodeOut_Air_ AH1, !- Comp4 Outlet Node Name
PASSIVE; !- Comp4 Branch Control Type
Of course, you will need Splitter, Mixer, Direct Air and a variety of
other objects to make the Air Loop complete; Don't forget those! It
will become very similar to your other two zones.

3) Your Steam Boiler has only one branch, named "1405 branch". At the
least, if you keep the Steam Boiler, you will need an inlet and outlet
branch, similar to what you've created for the Hot water Boiler.

4) The Steam Boiler now has inlet and outlet nodes that look
incorrect. They appear to be from an air loop....

That's all for now.1

--- In EnergyPlus_Support@ yahoogroups. com, D T <ellinas.1984@ ...> wrote:
>
> Thanks for the suggestions. I created a Coil:Steam:AirHeati ng object
and connected it to the Furnace:HeatOnly object. However, I am having
problems connecting the Furnace to the boiler. I read the error
messages I am getting and I still cannot figure out how to fix the
problem. Apparently I am having a problem with the branches and nodes.
I created an AirLoop for the steam boiler. More or less, I am having
trouble figuring out how to correct my errors. Any help or suggestions
are appreciated.
>
> Thanks,
> Dimos
>
> P.S. I've uploaded my file.
>
>
> --- On Mon, 8/4/08, 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, August 4, 2008, 9:07 PM
>
>
>
>
>
>
> 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:AirHeati ng 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@ yahoogroups. com, 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@ yahoogroups. com
> > 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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