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[EnergyPlus_Support] Re: problem with TSC



Dear All,

Thank you for your keen interest. I appreciate your help.

First of all, the use of TSC in my case is to preheat outdoor air to reduce the heating load of the building . The base model is a building without TSC and I ran the simulation and found the heating loads (with idealloadsairsystem )and I used the hvac template object.
In the base model for ventilation , I used exhaust ventilation the flow rate which I took was the min fresh air requirements for laboratories ( my building type is a laboratory.)I have an architectural background and so far I have always used HVAC template ideal air loads. Anyway,

THE first idea was to put the TSC and couple it with IdealLoadAirsystem and compare the result if it is possible (since the only HVAC I am familiar in E+ is HVAC TEMPLATE Ideal load air system)  but in the I/O reference it says"Using the UTSC model requires specifying a
relatively complete HVAC air system that includes an outdoor air path. This will typically
require using a set of objects that, at a minimum, will include: AirLoopHVAC:ControllerList,
AirLoopHVAC:OutdoorAirSystem:EquipmentList, AirLoopHVAC:OutdoorAirSystem,
OutdoorAir:NodeList, OutdoorAir:Mixer, SetpointManager:MixedAir, and
Controller:OutdoorAir. A single UTSC can serve more than one outdoor air system but
requires also using a separate object, called SolarCollector:UnglazedTranspired:MultiSystem...." So from here I understood that I need more than ideal loads air system and I started following the default file in E+ named Transpired solar collectors.
In this file the objects related to HVAC are air terminal: single duct: uncontrolleD, coil:heating, airloop HVAC , FAN: CONSTANT volume
setpointmanager:singlezonereheat and many more.

I have one single thermal zone. What just I wanted is at first was find the monthly heating loads and after put the TSC find the new heating loads and later manipulate outdoor flow rate to see the differences

Finally, in some value range, play with tsc parameters such as emissivity of the collector , solar absorptivity of the collector etc.. to see how parameters affect .. the study is not about the HVAC part it is more about the TSC part.  but since I can not understand the HVAC system I modelled I can not interpret the result in an healthy way .

PS: my location is London ( ONE climate ) my observation is about the parameters of the collector as ý told !!! 

How can I send my idf file here or someone.??

--- In EnergyPlus_Support@xxxxxxxxxxxxxxx, YuanLu Li <yli006@...> wrote:
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> Hi, Jeremiah Your remark below is not related to the user's original question.  "I am wondering what you where referring to in terms of specific changes to the reference buildings that would down size HVAC equipment and reduce energy consumption? Basically I was just asking you to provide some examples of how to do it better- Or energy efficiency measures that you might share that we could all learn from.. "
> It is the job of the AP and bulding designer to inprove the energy efficiency.  I am not an AP nor a designer, therefore I am not interested. There are many EEM's.  Your  using the annual run control for simulation is also a energy wasting measure. (-EEM) I do not think that we need to discuss this topic any further.  I am not going to share with you all I know, by tradition and convenience.Your advice to use IdealLoadsAirSystem is good , but should be given with a warning.   IdealLoadsAirSystem simuation  will provide the building heat load and may not provide the necessary  interface to the TSC case.  You can use a spread to merge the two sets of result, after separate simulations.  You can also generate  a schedule file for the TSC capacity using the EPlus and weather file to reduce the building heating load with  the IdealLoadsAirSystem simulation. This is no long that straight forward.  There is no short cut, such as using parametric analysis, and not using HVAC systems. Actually, I do not know what is the 'Transpired' - SolarCollector.  What are the features of this type of solar collector? I asked whether he is using it as a shade, because he is installing the TSC on a South wall.  If the South wall is covered, less sun heating will be on that wall in Winter. Because I do not know what is a TSC, I do not know how the heat collected will be transferred to the building.   It is a general fact, if a person does not know which  variable to optimise, the parametric simulation would not work.  The user should study all the variable reported and then create his own format to analyse the result. I was looking for  more input from the original user, before providing my solution or advice  to his problem, if I have one..  If the user does not understand my questions, he should ask some more.
> After you have run the example file, go to the I/O ref. manual pdf and look at the output variable description for the objects used in the IDF.  Slowly all the variable would mean something you already know.  This is a normal learning process.  I read the whole manual in 2007, and am now still not up-to-date.  
>  Dr. Li   
>  To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> From: jcrossett@...
> Date: Tue, 14 Aug 2012 14:22:37 -0700
> Subject: Re: [EnergyPlus_Support] problem with TSC
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>       Dr Li, Your input on the list is much appreciated- and your opinions much respected, I personally thank you for your input recently. 
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> With regards to EEM's- LEED and ASHRAE- I am not implying you should be interested- more over I am wondering what you where referring to in terms of specific changes to the reference buildings that would down size HVAC equipment and reduce energy consumption? Basically I was just asking you to provide some examples of how to do it better- Or energy efficiency measures that you might share that we could all learn from.. 
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> To the original user- you might try to model your system with an ideal loads HVAC for simplification- 
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> All the best-
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> Jeremiah D. Crossett  | Senior Analyst  |  Phase Change Energy Solutions
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> 120 E. Pritchard St.  | Asheboro, NC 27203  | Mobile 503-688-8951
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> www.phasechange.com 
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> On Tue, Aug 14, 2012 at 1:49 PM, YuanLu Li <yli006@...> wrote:
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> Hi, Jeremiah
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> I did not discourage  the user who asked the question, that EPlus is not suitable for him.
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> Your comments on his project are very good.  I do not say thing and provide answers, until I know what the user was really interested.
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> If you think that parametric analysis can work for a beginner using  unknown variables, I am not going to argue.  There is no short cut to success.  A craftsman much know how to use their tools.  "this is the optimal configuration of transpired solar collectors in climate zones xyz.." , if you say so.  
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> Actually, when I said  that it is no need to simulate the panel with EPlus, I meant just the same as I said to you that thee is no need to simulate your PCM properties with EPlus.  They have nothing to do with the building directly.  You are doing material property and application research.
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> To the user who originated the question:
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> All you need to do is to find out the capacity of the panel at different time of the day and year.  The solar collector  example showed you how to do this without the building geometry.  The maximum amount of DHW you can get, is the maximum saving you can get.  With real buildings, there is an added factor.  You may have more solar energy than what you need to heat the building.
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> At different location, the optimum mounting position of the panels would change to follow the sun orbit..  This is all you need to simulate using EPlus.
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> Regarding  ---     "EEM is Energy Efficiency Measure- and I am still wondering what you are suggesting? Possibly ASHRAE, NREL and PNL should be aware of your EEM's since apparently they are all way behind you. "   
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> I  do not really understand what Energy Efficiency Measure means.  Do you really think that the LEED certified buildings are Energy Efficient?  If you think that  the commercial reference buildings  are energy efficient as they are, so please continue to believe it that way.  I am  not interested.
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>  Dr. Li   
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> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
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> From: jcrossett@...
> Date: Tue, 14 Aug 2012 11:44:24 -0700
> Subject: Re: [EnergyPlus_Support] problem with TSC
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>        Possibly this application is to  pre-heat air for an HVAC system. Parametrics are the single most important use of simulation tools, I think you are on the right trek and encourage you to check into jE+ for its ability to compile results of hundreds of runs into a single CSV file that can speed the regression analysis significantly. You may wish to use one weather file location for each of the ASHRAE climate zones and up to 5 parametric values (more might be to much output data to deal with) Once you have explored all that you can think of so far as parametric runs, then you may wish to come up with sets of stochastic/unknown values with limits- say high and low or ranges between values- then setup a Genopt run for each of your locations. The benefit in doing parametric before optimisation is that you can learn from the results of your parametrics and limit your optimisation values to the best options that you need an optimisation algorithm such as Genopts "particle swarm" to solve the best answer for.
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> Your final paper could read like- this is the optimal configuration of transpired solar collectors in climate zones xyz..
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> Back to your original question- HVAC- the ideal loads HVAC system is designed for analysis that does not involve having a detailed understanding of HVAC systems. You did not include any SVG or IDF file to look at, nor an err or description so I can not really help with your actual issue- possibly if you need I could generate an HVAC system for you in design builder if you need...  
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> All the best wishes and good luck with your model.. 
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> Dr Li, TSP is transpired solar collector, it is basically solar heating system using unglazed air collectors with common applications in industrial and agriculture situations to raise ambient air temperatures, or for a pre heat of air into an HVAC system. Energy Plus is a great research tool, and is more commonly used by researchers than any other modeling tool, this is the perfect use of e+ and I do not understand why you are attempting to discourage its use?., Also from the other day about your statements that the commercial reference buildings are not properly designed and I asked you to specify what you thought would make good EEM's- EEM is Energy Efficiency Measure- and I am still wondering what you are suggesting? Possibly ASHRAE, NREL and PNL should be aware of your EEM's since apparently they are all way behind you. 
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> Jeremiah D. Crossett  | Senior Analyst  |  Phase Change Energy Solutions
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> On Tue, Aug 14, 2012 at 10:51 AM, YuanLu Li <yli006@...> wrote:
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> What is TSC/? TranspiredSolarCollector?  What is the thermal performance of a TSC?
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> How are you using it?  Using it, for example,  as an external shade? 
> If you do not have asystem or model which may work in real live, it cannot be simulated.
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> I do not understand how you are going to use TSC to reduce the heating load of a building.  Parametric study will not get you anywhere, if you do not understand the properties of all the variables.
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>  Dr. Li   
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> To: EnergyPlus_Support@xxxxxxxxxxxxxxx
> From: mumcuece@...
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> Date: Tue, 14 Aug 2012 16:42:50 +0000
> Subject: [EnergyPlus_Support] problem with TSC
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>       Dear All,
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>  I am undertaking a dissertation on modelling the thermal performance of TSC in E+ So far, I have read I/O reference and I have been following the default file TranspiredsolarCollectors which comes with E+.
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> But the problem is , since I followed the default file and the documentation, I ended up modelling a great amount of HVAC objects which henestly I do not know what some of them do, (I am not familiar with the mechanical part of E+ and in general also). However, I managed to model the TSC ( by copying the office 11 features in the default file) and it runs now however , I can not interpret the results. ( there are many outputs such as direct air sensible heating energy, air loop total heating energy, zone system sensible heating energy etc . 
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> My geometric model is a simple box ( 25X15X8) . The TSC is on the south wall. What I need to do for the dissertation, is to find out how much decrease in heating loads is gonna happen with A TSC(my base model without a TSC) and later I need to play with the outdoor flow rate to see how it afffects the heati,ng loads and the effectiveness of TSC. The final part will be parametric study ,changing one variable at a time to find out how it affects the TSC output.
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> However, there are so many control mechanisms,setpoints, schedules and I can not get the hang of it and I got stuck !
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> Is there anyone out there who have already modelled TSC . I would be grateful if I get some help with HVAC PART.
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