All right, so getting started with efficiency measures.
We're going to talk about efficiency measures in EnergyPlus
and efficiency measures in EP3.
Efficiency measures in EnergyPlus are done using parametrics
and so there are a couple of parametric objects in EnergyPlus
and this should be looking pretty familiar now.
So this is from the IDF editor.
We have a parametric section
and then a couple of different types of objects.
For the first time in a while, we actually only have useful objects.
We don't have a whole bunch of extra ones, so this is nice.
We have four different object types we're going to talk about today.
So in EnergyPlus, parametrics can perform kind of text to search
and replace level changes to the file.
So you're not going to make massive changes to the file
with most of your parametrics.
There's an object called parametric logic
which can control whether an individual object is included in a particular simulation
and it can also do some other types of calculations.
So you can do more advanced stuff with parametric logic.
I don't use this a lot, but every once in a while it can make a lot of sense.
So in order to explore this, we're going to take a look at an EnergyPlus example file
and so I want you to pay attention here because not just to the parametrics,
but this is a process that I use when I'm exploring a new part of EnergyPlus
or a new object type in EnergyPlus.
So the first thing that I'm showing you here is that I'm looking
in my EnergyPlus installation folder.
This is actually 24.1, but that's okay.
And then the subfolder is example files
and the file is example files dash object link.
And the column on the left, I've cut off the column headings,
but the column on the left is a list of all of the different types
of EnergyPlus objects that are available.
So I've taken a look for parametric file name suffix.
And then you see in these columns there's the number of files that use the object
and then the total number of times that the object is used in the example files.
So I'm going to take this one and only file that has a parametric file name suffix object.
And opening it in the IDF editor and I can look at the parametric objects in this file.
So it has the file name suffix and it also has set value for run.
So it has two out of those four parametric objects.
So this is the workflow.
We're working with a new EnergyPlus object and we're using, we're also going to use the description
in the IDF editor to look for information about the object.
So this is telling us a little bit about the parametric set value for an object.
So parametric objects allow you to set different values for the, basically we're going to create
this tag and the format is a dollar sign followed by a string with no spaces.
And any place that this is used in your EnergyPlus file, you will have basically a text search
and replace.
And in this particular example, we have four different runs and we have dollar sign at G angle.
And so I think most of you would kind of guess that this is probably going to change the
building rotation for some baseline appendix G runs.
Here we have the description up here and this tells us a little bit more about what's going on.
And then in this is a portion of the input output reference.
So from day one, we were talking about the resources available to us in EnergyPlus.
The input output reference gives a list of all of the different object types in EnergyPlus.
So this is giving a little bit of information about the general information about the parametric set value for run object.
And it's telling us about the fields.
So we have a parameter name and it's telling you again if the link must begin with the dollar sign character,
second character must be a letter and cannot contain any spaces or any characters other than letters and numbers.
And then the value is just a value that you want to use and you have one for each run in your file.
And then the file name suffix is you only have one object in your file.
So you don't want to have multiple file name suffix objects.
But for each run, you can add, you can include a string here which will be appended to your file name.
So this file name is L building app G wrote par.
It's a mouthful.
And then when you simulate, you're going to have, I think it's an underscore and then followed by these suffixes here.
So when you simulate this file, you're actually going to have four different runs or different simulations.
You don't have to have a file name suffix object in order to run parametrics.
If you only have a parametric set value for run object or multiple parametric set value for run objects, it will still run the different alternatives.
It will your file names will just have a default kind of one, two, three, four file name.
And I can find that I find that fairly confusing.
So I highly recommend if you're going to do parametrics in directly in energy plus create a file name suffix.
There's also this parametric run control object.
And it's used to specify whether that run should be simulated.
It's not required.
All runs will be simulated by default.
But in this case, we're going to say yes, and we're going to perform all of these different ones.
If we search for the string, the dollar sign app G angle and the IDF file, it, it shows that it's used in this compliance.
So we have the parametric set value for run, and it's used in this compliance building object.
And you'll notice that it says equals dollar sign app G angle.
Okay, and then, then we have a different file.
This is the one zone parameter aspect file to look at the parametric logic object.
And this is kind of a mouthful here.
We have a whole bunch of different parameters.
And we're declaring them.
And then we're running some calculations on each one of them.
So we have a building area parameter, a depth, a width and a height parameter.
And I just, I don't want to get in the details of exactly how you do this logic.
But if we look in these building surfaces, you can see that we actually are specifying some of our coordinates based on the height and width and depth parameters.
So what this example file is doing is it's running a couple of different simulations where it's changing the aspect ratio.
So it's calculating the building area is staying constant and it's calculating the depth and the width based on a changing aspect ratio.
And so this is, this is a fairly powerful, fairly interesting thing that you can do with energy plus.
And I'm doing it on a large complicated model would be a bit, it would, it would be incredibly difficult.
However, for simple studies where you want to get some, some answers about how aspect ratio changes your building, or you can use, you can use logic and calculations to change certain things about your building by using these parameters.
So I think this is a, an interesting thing to know about energy plus, you probably won't use it right away, but maybe two, five, 10 years in, you're going to remember this and say, Hey, like there, there's something I want to investigate.
And this seems like it would be useful.
Okay, so let's, let's discuss some pros and cons of energy plus parametrics.
I'm going to escape out of this.
So I can make a list here.
And again, I have a bunch of ideas to hide those.
But give me some, give me a couple.
I will say that the energy plus parametrics when you simulate your file, it automatically simulates all of those parametrics that were enabled in the simulation control object.
So every time you simulate your file, it will simulate all of your parametrics, all of your parametric runs.
I'm going to start off one pro is that this is, this is really fast text search and replace.
Okay, it's quite fast.
A con is that between these different object types.
What value for run parametric logic run control and file name suffix, you have to coordinate everything just by run number.
So it can be quite confusing to figure out if you have more than just, if you have more than one parameter, it can get really confusing.
And a lot of files where you have where you want to run parametrics, you're going to have multiple parameters, if not tens, or even 100 different parameters that you're changing.
Are there any additional comments or ideas questions come in on this.
Those. No, nothing has come in. Those are the exact ones that I would have said.
Okay.
Oh yeah, condor also it's quite limited.
Okay.
Let's go and take a look at a potential con is increased runtime. If you just want to run the baseline, or one of the runs. I think that that's solvable.
Yeah, yeah, there is increased if you forget to turn off a parametric, then there is some increased runtime. Another one is that it's a little bit difficult to describe here, but because you have it makes it more complicated to view results.
Because you're you're getting a different report for each one, you're getting a different report for each one. Yeah.
Okay, so let's take a look at.
Parametrics and EP3 so in EP3 we call parametrics efficiency measures or EEMs.
And with EP3 we make changes directly to the model it's a it's a what you see is what you get kind of a situation.
You can add EEMs and we just, I'm just setting up a low lighting power density in this model. So once you add them.
You have it available in the list in your global settings. So right now we're still in the base EEM.
And I've just switched to the low EEM or low LPD EEM. And I'm just going to pause this second.
Okay, in.
When you're in an efficiency matter or you're in an EEM that's not the base EEM.
EP3 will highlight any fields that inherit a value from the previous EEM.
So this is a convention that we use all over in EP3 and there'll be more of this when we start talking about.
Particularly zone HVAC equipment that sometimes there's data that is stored elsewhere that we're inheriting in a particular location. So here.
All of these values.
Are except for the Watts per floor area. All of these other values are being inherited from the base EEM. And this is the low LPD EEM.
So we've reduced the Watts per floor area.
If I select more than one object, I can change the value in multiple objects at one time.
So now I have an efficiency measure that is reduces the lighting power density and the circulation and the hardware wired lights.
We can layer multiple EEMs on top of each other. This is a major advantage over parametrics and energy plus.
So I'm going to add a another EEM. Actually, I think I'm going to add a couple of EEMs related to the building envelope.
And right now I'm just creating them and name naming them and then I will go in and update the values in the file.
Okay, so now I'm going to look at materials. So the exterior wall material and I'll go to the high R value.
Efficiency measure and change the exterior wall R value.
Going to the high roof efficiency measure. Again, I just changed the R value in the roof construction or I'm sorry, the roof insulation.
Okay, so here we have a list of each efficiency measure in the model. You'll notice we don't have the base EEM listed.
The base EEM is always the base. It never inherits from anything else. It is the kind of baseline for your file.
And next to each one we have a list of all of the other efficiency measures in the file. And what I'm going to do now is just click.
So in my high R value or sorry, high R walls and roof efficiency measure, I've included the previous efficiency measures high R walls and high R roof.
So if I change to that efficiency measure, you can see that the R value for the roof and the walls reflect that higher R value again here.
Because we're now inheriting these values from a previous EEM. They're now showing up as red because they're inherited values.
We can also include or exclude objects in an efficiency measure using the user interface and it's what you see is what you get results. So we'll create another EEM.
And we'll call it fan coil.
So this is a fan coil object.
And with HVAC equipment and with Windows, you can turn these objects on and off in different EEMs. So we have a VAV and a fan coil EEM in this particular model.
So now everything that's related to the VAV system, I can turn off in the fan coil EEM and turn it on or the VAV EEM.
And then when you switch back and forth, those objects show up or disappear.
So when you look at your model and you select your efficiency measure and then you explore your model, you should be able to see very easily what is actually going to stay in your model for that particular efficiency measure.
When we were creating, when we started creating EP3 years and years and years ago, we were coming from EQuest where you can do some pretty basic parametric runs.
It's a lot like the energy plus parametrics where you can do text find and replace and a little bit of logic, but not a whole lot.
And for most of our projects, we were being asked to compare multiple different HVAC systems.
And we ended up having to create and maintain any changes that happened in the base model.
If there were architectural changes, we were having to maintain three, four, five or six different EQuest files for every single project.
And it was absolutely exhausting because invariably you miss an update to a schedule somewhere.
EQuest also automatically creates, we were talking yesterday about a lot of projects have way too many schedules.
EQuest will automatically generate a set of schedules for every single building shell.
And if you have a model with kind of complex building geometry, you could end up with a lot of different schedules, which require a ton of cleanup, or if you don't do the cleanup right away, you're maintaining things later on.
So it was really important for us working with EP3 to just have one model that if a change was made to a schedule or an internal load or the architectural system that we would just change it in one place.
And then all of the efficiency measures would still, would update automatically and be available to us automatically.
Speaking of EQuest, we had a question come in, that's a really good question.
In the past, I've had to ensure that EEMs are in the correct order before running the model, EQuest and EnergyPro.
Is that the case with EP3 as well?
And I think the answer depends, but I'm sure you know.
Yes, so order does matter if you are editing multiple, if you're editing the same value more than once, and you have that same value edited multiple places in that EEM change, the order that you have your EEMs matters.
But let's see.
And I would imagine if you switch the system type and then you need to change a variable within that system, you would have to change the system first and then change the variable within that system as you stack them.
Yeah, so we generally recommend that you have all of the systems on in the base EEM and that you make changes in the base.
The system wide type variable changes in the base EEM.
But this is with EP3, it's also, it's also what you see is what you get.
So like with this high R value walls and roof or with any of them, you can, you change the order just by clicking and dragging.
So a couple different places in EP3 where you'll see these buttons that light up to kind of a gold color, and they're always these like draggable lists where you change the order.
So if we had conflicting values, it basically will apply this one first, and then if these values can reflect it will overwrite here and then this one will overwrite this.
Okay. Oh, I'm just have a question that I thought was now was a good time. So is this six additional EEMs right here, or is it more?
I'm sorry, can you clarify how many times is the simulation going to have to run to process these EEMs it looks like you have
six EEMs and if you make multiple changes in one EEM.
I mean how many runs is this right here that we're looking at.
Yeah, so this is 123456 and then the base EEM so you have seven different models that you can simulate.
You don't have to simulate all of them, and like you can simulate any individual one.
And you can have multiple changes in each run.
You can change as much as you want in an efficiency measure.
You can change it absolutely as much as you want.
Just keeping that clear. Okay.
Yeah, and I think one of the things that's quite difficult about EQuest and making sure that everything is in the right order is that there's no way for you to verify anything until you simulate the file whereas here you make your change and then you just look at your model.
So if I changed my EEM bases and I added this.
Oh, I actually don't have a let's see let's do a.
Coil so I've added an EEM that's named fan coil.
And then I am going to.
Enter into my.
You can if when you click on the HVAC group, the entire thing lights up, you can either double click to get into it.
Or if you click on any of these objects in the outliner, it will bring you into the group automatically.
I'm now going to select all of the objects that are connected to my air loop.
I'm going to surround them.
I don't quite have this heat recovery device and the outdoor air mixer to hold control down to click those two.
And then.
Go to my selected object dialogue.
And click manage availability in EEM. So now I have a list of all of the EEMs.
And in my fan coil EEM.
I will turn those off.
Okay, so now if I go to fan coil.
Those objects are often I just have my fan coil object.
And under this high are walls and roof if I click fan coil as well.
And I change.
Let's go to basic EM to turn everything back on just so visually this makes sense. And I go to high are walls and roof.
You just you see right there what the what the values are.
So yes, you have to make sure that things are in the right order. However.
Because it's a what you see is what you get model when you when you change EEMs when you switch EEMs you will see what's there and what's not there.
For.
For objects that don't have a direct physical representation such as lighting objects and.
Gas equipment other things.
Some things are hidden behind my zoom toolbar for a second.
Okay, so for a lighting object and I'm in this high are walls and roof efficiency measure for any object that's in this list here if you scroll all the way down.
There's a little checkbox next to here that says include in EEM and then it'll tell you what the EEM is.
And if I uncheck this box.
Then in this list that particular object will show up in red. So.
When you look at a list of.
Objects here you can see quickly anything in red will not be included in this particular efficiency measure.
Questions so far on this. So what you're saying right there is that you can refine an EEM to apply to just part of the model.
Yeah, essentially. Yeah.
Yeah, and it's nice to be able to see it. You definitely cannot do that in the equest. In fact, equest has to regenerate the file each time you calculate.
And it creates a new.
Equest file for each one of your parametric runs, which is also slows it down every time you simulate.
Yes, so that is the 1 drawback of EEMs in EP3 is that.
When you, when you simulate an EP3, there's a an export process, which is not lightning fast. We're working on making it faster, but it's not lightning fast.
And then there's the energy plus simulation for each EEM. It goes through the complete export process.
We've experimented with kind of saving certain data, but it just doesn't come out quite right. And this is 1 of those places where for now, having something robust is more important than having something that is fast.
So the energy plus.
Parametric.
I don't think we have the parametric logic, but the parametric file name suffix run control and set value for run are available in EP3. So very simple changes.
You, so you can have some energy plus parametric stuff that's set up in EP3 because you, you will simulate faster.
So, yes, that, that is the 1 sort of big drawback to EEMs in EP3, but we found that the reliability that you get.
If far outweighs the performance.
I assumed that it would have to make a new IDF file for each series of EEMs. I can't see a different, I can't see any other way that that you can really do that and have it be robust.
So, yeah, makes sense. And that's exactly what EQuest does though. EQuest is not as robust.
Okay, so let's, let's just make a little list here. We just talked about some.
We had a question come in. Yeah, go for it. Will the final EEM include interactivity with all previous EEMs. And I think obviously it can if it needs to.
Yes, so if the, if the EEM.
If it has other included EEMs, then yes, so this high R walls and roof EEM.
It includes, let's, let's keep this open.
So it includes the fan coil EEM. So if we go, if we remember the difference between the fan coil EEM and the base.
We had turned off the VIV system and we look at high R wall values or high R walls and roof. It reflects the same HVAC system here.
And then the high R roof.
We had residential roof construction right here. This is a white background. So we know that this is the exact location in the file where this value is stored.
If we go to our high R walls and roof.
This value is being inherited.
So yeah, so the high R walls and roof is the cumulation of fan coil high high walls.
Hi, our roof, we didn't, we didn't verify the high our walls, but I hope you.
Take my word for it on that.
Yeah, so I think the root of that question is that the final, you, this isn't entirely linear. It doesn't have to be based on previous.
You can branch out into different EEMs.
Because we're switching the Swiss system type on one of these. And obviously that that can't accumulate with all of the EEMs. It's more of a web than a line.
Yeah, yeah, you know, we, we used to do this linearly and then it gets to be a bit of a pain. Like this is so flexible and so fast.
And, you know, you do need to be careful because if you base another EEM on high our walls and roof.
We, we didn't store any data directly in this EEM.
So it's only picking up the data that's stored directly in this EEM. So if, if we base.
Low LPD on this high our walls and roof.
And then we switch to low LPD.
And we look at the roof construction. It doesn't have a high R value.
Because that stored it, that value is stored in the high R roof simulation.
Not in the high R walls and roof simulation. So it, it can, it's a little bit challenging to really deeply describe. However.
What you see is what you get in the model. So the first couple of times you do this and honestly.
The first, you know, really verify that you have the values that you want until you're really, really sure you understand how this works.
But you just turn the EEMs on and off that you want to inherit.
Go to that particular efficiency measure and just verify that everything is there.
Does that make sense? Make some sense.
It makes sense to me if anyone has any questions on that.
What you see is what you get is very useful. And I think this is one of those things that you can learn really quickly.
But you just have to do it.
I think you have to play around with it a little bit. It's, it's tough to really describe.
And there was a lot of, there were a lot of iterations of how this worked before we got to this one and this one is the, the most absolutely the most flexible and easiest to use.
Yeah, and I see the flexibility is what makes it somewhat confusing, which is always what you get with flexibility.
No, the, the number of permutations that you have here is much, much higher and more powerful. So that is the bonus to the part that makes it a little bit, a little bit more confusing.
Yes. Yes.
Yeah.
Are there other questions or should we fill out that kind of pros and cons list for the EP3?
There's no other questions on the list here.
Great. Okay, let's, let's fill out some of these pros and cons on the on the EP3 efficiency miners.
Well, it's very flexible. I'll start with that one.
Okay.
All right. Well, the flip side of that is that it can become confusing with flexibility with the added flexibility.
I think it's simple in terms of basic EEMs.
I think the biggest con is that it requires, EGEM requires a complete EP3 to IDF export.
I'm going to highlight this one because this is the, there's a big, big advantage for us that you only need one EP3 file for an entire project.
And that works in conjunction with the WYSIWYG.
Yes. Yeah.
I have had some people ask me about scripted measures because Open Studio relies on scripted measures and they can be quite powerful.
We haven't really found the need to do scripted measures in EP3.
So if any of you get to the point where you really, really want to script some sort of efficiency measure in EP3, please let me know.
In most measures can be done, what you would need to write a script for can be done with a couple of clicks in EP3.
The exception is a complete baseline model generation and the ASHRAE 90.1 and PENDXG baseline is our primary development priority at the moment.
So that reminded me of another pro here is that you can apply things in bulk.
Yeah.
I don't know how to phrase that better, but you can make changes, you can make changes universally.
Apply changes in bulk is fine.
Yeah.
Because that's where scripting comes in as far as I understand in Open Studio.
Yep.
Yeah.
The other con is I think everyone's either confused or too confused to ask a question, but I think that this is pretty easy to learn with once you play with it.
That would be a pro.
That would be a pro.
Okay.
Yeah.
Okay.
All right. So now we can move into troubleshooting.
Okay.
That's a little bit overwhelming day four troubleshooting models and quality control.
So today, the second part of the session, we're going to talk about troubleshooting and quality control.
So some of the questions for troubleshooting is, why isn't my model simulating?
How do I reduce on my hours and quality control would be, is my building logical?
Is the model valid?
Are my results reasonable?
And is my model doing what I'm expecting it to?
And we are never going to be able to answer all of the questions about how to troubleshoot and how to check for quality control.
What I would like to do is share a couple of a couple of methodologies that I like to use that have that can be applied at a much broader level.
So, first of all, sometimes it's just good to do a double check and say, is my building logical?
I've modeled this particular building.
It has the bottom floor, a top floor and a middle floor with the multiplier of seven.
And I just want to make sure that that, that I have the area and the volume that I'm expecting in my building.
So I'm just going to do a couple of gut check calculations on my building and see if everything looks right.
Okay, so this right here is a report.
It gives the window to wall ratio of the entire facility, but it also gives the above ground and growth wall area of each cardinal direction.
So really good check for most normal buildings that don't aren't built into a slope or have vastly differing, you know, weird angles and vastly differing roof surfaces on one side versus the other.
But this is a rectangular building. The surface area on the north side and the surface area on the south side should be the same.
So here we go. We're just checking north versus south. It's the same.
And same with east and west. That is the same as well.
We can also double check the floor area and the volume.
So over here in EP three, I clicked into a, I'm going to, I'm going to slow this down. I'm going to actually show you this in, in real time so I can go a little bit slower.
I would suggest to have the practice to do most of your editing in the base.
Except when you're explicitly doing something that's for an efficiency measure.
Get in the habit of just sort of living in the base EM and then switching to another EM just to make changes for that particular.
With the, with the HVAC systems, I like to put everything and make everything visible in the base EM and build out all of my connections and then turn, you can turn objects on and off and you can adjust efficiencies in EEMs,
I like to kind of have stuff connected in one EM that's not connected at the baseline that just gets a little bit messy. So just a general workflow sort of thing as we're talking about EEMs.
Okay, so in order to double check my surface area, all of my floor plans for this particular building are the same. It's quite simple.
I'm going to click in to edit the ground floor. So if I click here, I have the ground floor selected, but I'm not actually editing it. I click the arrow on the right. I'm actually inside the ground floor.
Right now I can see the rest of the building, but if I click on this toggle exterior geometry visibility, we can turn all of that off.
I'm just using the scroll bar on the mouse to do a little zooming in and out and pushing on the scroll bar lets you orbit as well. So a quick couple of shortcut keys.
In SketchUp, on the right, there's this default tray. I can pin it here. And if I pull this down, this gives me information. Entity information gives me information about whatever is currently clicked.
So if it's a face, it will give me the area. So if I select all of these faces, I will get the total area of this floor.
And if you double click a face, it will select the face and the bounding edges. And if you triple click, it will select the face and everything that's connected to that face.
And then there's an extension that I use called selection toys.
You can give you a link to it, but if you right click and then say select only faces with just a couple clicks, I now have the surface area of this floor.
I believe here I go through doing that a lot faster.
And then we have nine of those floors.
And if we multiply 277 by nine, we should end up with this number right here, which is the total condition area of the entire building.
We also have the volume and we can double check that by multiplying in this case to this particular building.
We can multiply the floor area by the height of the walls to double check the volume.
Another way to check quality control is to just look at your schedules to the yearly schedule values make sense.
So on the left, I'm looking at a fan availability schedule. So it's on and off and I can compare there are a couple different time periods.
So in this case, the fan is available.
I think I think it's available all the time during the winter, but during the summer, it's just available during the day.
And so we can verify that this number of hours for the fan availability schedule kind of makes sense based on the schedule that I see on the left here.
We can also double check like an always off schedule has a total number of hours of zero and always on has a total number of hours of 8,760.
So those, those look correct.
I would add here that reviewers check your equivalent full load hours. So it's definitely something that you want to check in your quality control.
Yeah.
Okay, we also have our favorite a met load hours if you're.
Heating and cooling hours are met.
That is an indication that your building is running well.
You can also take a look at this on a facility entire facility and on a zone level.
And look at the number of hours during heating, cooling, and then there's also occupied heating and occupied cooling has gotten cut off over here.
But if you have any really high number of on that load hours here.
The 1st thing I go is I take the take a look at this list and I see, okay, as are those on that hours spread out over the entire building, or is there 1 particular zone? That's an issue.
Next, we're going to take a look at the error file. So, again, there's tons and tons of different types of errors that energy plus will give to you.
We are going to look at the format of some of those errors and the different types of errors and go through a process to kind of inspect what's going on.
So this is showing you how you can get to your error file through EP 3. Even if you don't have results, you will have that button to get to the error file.
Let's just play that again here.
So here is the button for the error file right here. These are the different files that were produced by this particular simulation. So we have errors, IDF, we have output tables.
We have the RDD file, which we discussed yesterday. This tells you all the potential output variables that you have.
And then these are our hourly output variables and the ESO file, which is a output in a different format. I believe Design Builder has a results viewer that works with ESO.
Okay, so when we're inspecting the error file, there are a couple of different types of errors. So warning is supposed to mean take note.
Severe is you should fix and fatal means that the program has aborted.
The meaning of severe is a little bit, it's not super consistent. The meaning of a severe error in energy plus. Sometimes it's sort of like a warning.
And a severe error will always precede a fatal termination of the simulation, but some severe errors are not very severe and some of them are quite severe.
So don't freak out if you have some severe errors in your error file, but your model is simulating and you're getting and you've done some of your other quality control checks and everything makes sense.
Okay, so let's take a look at a particular warning. So we have this warning, which is related to this will tell you a little bit about the process inside energy plus where the arrow was raised.
So processing the schedule input.
It's related to a schedule compact object with the name HVAC template always on and this right here tells you a little bit more about the error. So blank schedule type limits name input and then will not be validated.
So if we look at this object schedule compact with the name HVAC template always on and then we look at schedule type limits name right here.
Okay, yeah, it is blank. So we don't know what type of schedule it is. And this is just telling us energy plus can't validate the values in this schedule because we don't know we don't have any parameters for them.
This is a little bit of a review of yesterday of what the schedule type limits does, which is it tells us our upper and lower bounds for our values in our schedule.
And also the type of values we're allowed to have are they discrete or they continuous.
Okay, here's another one. So warning.
And this is related to a building surface detailed named ground floor 05 residential apartments and then a bunch of numbers.
And it says the sun exposure is sun exposed, but this surface is not exposed to the external environment.
Sun exposure has no effect. So here we have our building surface detailed ground floor 05 residential apartments, blah, blah, blah.
And if we look at the sun exposure.
There's no input here. Okay, so what's going on? There's no input, but it says that it is sun exposed.
Okay, let's take a look at it in EP3. This is the same surface we have selected ground floor. You can't see the entire name.
We see the warning over here.
And if we zoom in, this is a little bit blurry, but I have moused over the sun exposure input.
And it says telling me that the default is sun exposed. So over here, when there's no input here, energy plus is automatically giving it a sun exposed default.
So what they're just telling us is that they're going to ignore that sun exposed input. So again, this is a warning, but it's just kind of telling us, hey, we notice something in the input file.
And we think the simulation is going to act a little bit different than you're expecting. That's essentially what this morning means.
Okay, here's another warning.
Warning, since zone minimum airflow input method equals constant input for fixed rate minimum airflow rate will be ignored and occurs in air terminal single dot DAV.
No reheat. And then it gives the name. So this, this has a little bit different format. The warning and the information is first.
And then it tells us where this is. And I apologize. I had a line break in the middle of a word here.
But if we go to an air terminal single duct VAD no reheat. So these are new object types. These are HVAC object types.
We'll be talking about zone HVAC equipment on Monday. But again, today I'm trying to show you a method for parsing some of this.
Initially sort of scary gibberish stuff. So we go to air terminal single duct VAD no reheat and we look for this minimum airflow input method.
So the minimum airflow input method is constant. So we have a minimum airflow fraction.
And then it says the input for fixed minimum airflow rate will be ignored. Okay, the fixed minimum airflow fixed minimum airflow rate is auto size and bold here.
And indicates that this is a required field. So we are required to have something in this field.
And yet it's going to be ignored. I think this, this warning. So I'm just illustrating that sometimes energy plus is.
It's requiring us to have something here in this particular case. They're ignoring it. They're just letting us know, hey, we're going to ignore this field.
All right, here's another one. This is a severe error.
This says, so up until now, all of these warnings, they're just telling us your inputs are going to act a little bit different than you might be expecting.
This one is a severe. It says water heater mixed.
This is the name water heater. The name, the name of the object in the air fire will always be in all capitals. And it says ambient temperature zone not found. And it says equals.
There's actually, we'll see there's actually nothing listed in the ambient temperature zone. And so it equals blank.
Here's a water heater mixed.
I've skipped a whole bunch of fields because I don't have room on the screen to show you all of them.
Here we go. And ambient temperature indicator is zone. You can choose a couple of other things. You can choose a schedule. You could choose outdoors, but we've chosen zone.
And yet there is nothing in the ambient temperature zone.
Now, because a water heater has an off cycle loss coefficient, which is in the units or v to use per hour per degree Fahrenheit.
If we don't have an ambient temperature specified in the water heater, the water heater won't have any.
Any loss from to ambient temperature. So the reason this is a severe error is that actually.
The calculation for the water heater is a little bit incomplete. It's still going to simulate. It's not going to crash the program.
But this is something we actually need to take care of or we need to choose that the.
Water heater loss to ambient conditions is not important.
So it becomes adiabatic in this case.
Yeah, the water heater becomes adiabatic. It's still, it's still heating, you know, it's still heating the actual water load, but the water heater itself is not radiating to any zones.
And it's going to have a boost in the efficiency that is not going to be observed in reality.
Exactly.
And that zone won't have that particular load. So whatever, I think somebody yesterday was asking.
It was 2 days ago was asking about mechanical system and loads in a mechanical.
Space, so water heater would typically be in a mechanical space and the that space would be.
Potentially quite warm, depending on the efficiency of the water heater.
And if that space is heated that space is going to need more heat because it's missing that load.
Yes.
Okay, so we just looked at a severe error where the file is simulating.
But for some severe errors, the file will not simulate. So, right here, this is a little snapshot of what happens if you simulate.
An efficiency measure. And right now I'm giving a little clue about why this file isn't simulating. I've created an EM called no pump.
And when I simulated it, I get nothing in the results.
And all I have are errors and IDF. So, thank you.
This is also showing you if you look at this file, this would be no pump IDF file.
If you look at it with EP launch, you'll see that with all of your results files, the only thing that's available is this errors file.
If you, yeah, you know, yes, errors is pretty much for most simulations. That's all you're going to get.
So, these are the fatal errors. And there's a fatal error in this file right here.
This actually is the entirety of the error file for this particular simulation.
Usually when there's a fatal error, the error file is a lot smaller and shorter.
And because you get a fatal error, you often get a fatal error kind of early in the simulation and the processing of the file.
So, here we go. Severe.
Plant loop, hot water loop. Okay. This, this is a name right here. It's not actually in all caps, even though they usually are.
And it says missing required property, plant side, inlet node name.
And then we see fatal errors occurred on processing and file proceeding conditions cause termination.
So you could potentially have multiple severe errors similar to the water heater error.
And if you go to the, if you do a tech search for fatal, it's usually the city or area error just prior to that fatal error.
Here we have the IDF for this plant loop.
Now we can see if we look for a field called the plant side inlet node name, there is nothing there.
Okay. Here on this plant loop, there is nothing on the supply side inlet of the plant loop.
Again, next week is going to be all about each VAC system. So this, these diagrams don't make a huge amount of sense.
That's okay. We're going to really dig into the, the details of these diagrams next week.
EP3, when we do the conversion to, to energy plus, we also, if we detect some issues, we will also give you some warnings.
So any objects that are say excluded from an efficiency measure, sometimes we will tell you about them.
But here there are a couple of warnings and actually all related to the eventual fatal error that we got in energy plus.
So there's a warning, there's a required field, which is plant side inlet node name.
So this required field is blank.
And then we also say no components found on branch supply inlet branch.
And then we have an error. Hot water loop has some branches with no objects assigned on the supply side.
Energy plus will not simulate pro properly.
This usually happens if a pump or adiabatic, adiabatic pipe is deleted.
So between the, the energy plus error file and these export errors, you should be able to hopefully start to figure out what's going on here.
Okay.
Some questions on what we talked about so far with model validation.
Nothing, nothing came in.
Okay.
I did have a question on one of them.
Oh, one of the things that I just, I had written for a question for later, you showed the unmet hours based on space type.
Can you check the unmet hours by system.
I didn't know it's not model validation, but it's quality control.
It's based on system.
Not directly. The unmet hours that I showed were based on zones, individual zones, not space type.
Yes, just thank you. Yeah. Yeah.
We can't.
I don't believe we can check it based on system directly.
But obviously you can make an inference.
And, and we will.
In the next will not next, but kind of at the end, we're going to, to talk about some techniques for.
Model validation or.
Validating that the model is operating the way that you wanted to.
By looking at detailed data.
And so, and then that workflow is something that you could use to verify or check which air handlers are.
Are satisfying or not satisfying the loads and the spaces.
Yeah, I don't, I don't think you can filter quickly by.
By system.
Yeah, that's okay. I just was asking if it was possible.
We could do it with the 3, but it's going to be if somebody wants to.
Incentivize the development of that, we would be happy to talk about it.
Okay.
Let's talk about some resources for checking whether your results are reasonable.
So, they, this is a snapshot from the energy star folio manager.
And they give some very basic source and site energy.
You.
UI values.
In kilobyte use per square foot for a whole bunch of different types of buildings.
This is, this is kind of a good gut check way to say, okay, am I within range of what I want.
The prototype building models, which I believe would develop. Yeah, they're developed by PNNL. They're also a massive resource, both for this.
So, thinking of are my results reasonable, but also as a reference for internal loads and schedules and system types. I mean, there are just there. There are so many models and they're all energy plus models.
So, here we have a residential building.
We have a total UI in, in international units of 277 kilowatt hours per meter squared.
And, and then this is a PNNL apartment building in a similar climate, which is at 423 kilowatt hours per meter squared. So we are not that close, but we can look through.
Some specific end uses and compare and think, okay, are we.
Is this reasonable? Can we justify some savings? Does this make sense? So this is a good way to kind of take a look and say, okay.
Let's do service water heating. I think it was quite a bit lower here. So in this building, we might be grossly underestimating the service water heating.
Maybe this is the same model that didn't have zone losses on the water heaters that might be part of leaving for it.
So you can go through and look and use by and use and compare and say, okay, are we close?
If we're not close, maybe there's a good reason for it.
This same residential end use for energy star, the energy star UI is quite a bit lower.
But also remember that energy star is for the entirety of the US and these 2 buildings are actually in the Northeast. So we're going to have much higher heating loads.
So this difference might actually be reasonable. But here are just some gut checks to say, am I in range of something that has been fully vetted?
There's another source for UI that I use sometimes. I can post it to the forum. I can't think of it off the top of my head.
Yeah, that'd be great.
So the prototype building models, they have standard 90.1 prototype building models for a bunch of different years.
And they also have the appendix G prototype building models for the same use types for a bunch of different years as well.
And these are the simulations on which the appendix G building performance factors, which are used for the kind of savings under, I don't remember which year they switched it with ashray appendix G.
But this is what those performance factors were based on all of these models.
In each of these zip files is a massive number. And I'm just sort of just sort of scrolled through for you to show you this is the hospital set.
And I didn't even scroll through half of them. But there is a an IDF file for many, many cities throughout the world.
And they've also changed the systems to be kind of appropriate for that part of the world.
So massive, massive reference for your use in energy plus massive reference for the quality control and validation of your models and also looking at being able to inspect these buildings in EP three to take a look at the systems.
It is a huge resource.
Okay, any questions on that.
Someone made a good comment here that CBACs has EUIs broken out by region size age use type and a ton of other things.
And I've used that in spreadsheets for quality control as well. So that's super good.
Good input there.
I should probably add that to a forum post. Thank you.
Yeah, I think this is this is one of those things where we can create a forum post with these different resources.
And there are a lot. The energy star and the PNNL are just, we're just two, but yeah, CBACs is a fantastic resource. Thank you to whoever mentioned that and added that that's great.
Yeah, okay.
And, and of course with EUI there is always going to be a pretty large standard deviation.
Yep.
Yeah.
You should have a good idea of what side of that standard deviation you are on based on your location and your, the quality of your building.
Yes, absolutely. And yep.
I'm building.
Okay.
All right, so.
Now I want to begin to a little bit different.
Technique.
This technique can be used for troubleshooting.
So,
every once in a while, an energy class file will sort of crash mid simulation and this, this can happen when you have some kind of like runaway temperatures and you'll get a severe error that says something about runaway temperatures.
And then the simulation will just sort of stop.
You can get
time step or hourly variables up until the point at which that the file stops running and those that information can give you some clues about what's going wrong and and why.
Those models are not all that much fun, but it does happen.
I'm going to show you how to get those output variables. We did this a little bit yesterday.
If you remember when we created the custom schedule, the first thing we did was we grabbed the outdoor air temperature.
Variable simulated the model and then use that outdoor air temperature to run all of our thermostat set point calculations.
Excuse me a second.
Today I want to share with you a model. This was actually was generated because a couple days ago I got a question from a customer and they said,
we are looking for software that can model a particular use case and
we can't do it with ISPE and we can't do it with equest and we want to know if it's possible to do with
energy plus through EP3 and their use case was
we have two chillers in series and we have a different set point
at the outlet of the first chiller than we do at the outlet of the second chiller. So I think it was 10 degrees C
at the outlet of the first chiller and then
five degrees at the outlet of the second chiller and they said can we model two chillers with two separate set points
and I was like, well, I think it can, but I'm not 100% sure. I'm going to go in. I'm going to run a
quick model and see if if we can do that. So this is the
this is my favorite example file. It's a five zone air cooled example file which
normally just has one chiller
on the chilled water loop. So here
we have the HVAC system outliner.
We have the VAV air system. We have a hot water loop and we have a chilled water loop.
I added a second chiller
and I added set points at the outlet of each of these chillers.
So what I think we're talking on Wednesday next week of about how to actually set these systems up.
So for now I'm going to ask you to trust me that the system is is set up. We have a set point on the outlet of the
of each chiller and we can actually take a look
at them.
So this
set point right here, we click on that schedule.
It is actually it wasn't five degrees C, it's seven degrees C
and we can change those units. So it's 45 degrees
on the outlet of the second chiller.
The first chiller is 50 degrees C.
With plant loops
we also need to kind of
stage the equipment and choose when we're using the equipment.
So we do that in energy plus with what we call operation schemes.
So in order to run this particular operation scheme, I'm using an operation scheme type called
plant equipment operation component set point. So I have an individual set point for each component.
And I've set, I've selected these two chillers
and then it's automatically calculating the
the set points at the
outlet node of these two chillers.
Okay, so I've already run this simulation.
It doesn't help us that much to view the yearly results. We could take a look at
we could look for the energy used by each chiller and see how much energy is being used by each chiller.
But what we really want is we really want to know what's going on at this
at the outlets of each chiller. So I've created
something called a node report.
And this is tracking the set point
at these two nodes.
We also have chiller outlet temps
and we're checking, we're tracking the system node temperature
at the inlet
and outlets of each of these chillers.
So once the simulation was run
because I have some output detailed output variables
in my results, I have this section right here which is out for viewing
detailed output variables. So everything is is at an hourly time scale.
And I have a bunch of different output variables. So first we're going to take a look at the
chiller to outlet temperature
and set point temperature and the chiller one outlet temperature and set point temperature.
So let's take a look.
This gives me the values for every single hour of the year.
And this is a bit overwhelming. It's hard to get really good information.
As you move the mouse, you can see in the upper right hand corner, I'm getting the
a list of the actual values for each time step.
But if I want to look in more detail, I can click and drag and kind of zoom in here.
So we can see the, the outpoint temperature of chiller one is 10.
And we're kind of always below that for chiller one.
And the set point temperature for chiller two is 7.22.
And most of the time we are meeting that set point temperature.
So I saw this and I thought, you know, I wonder why I wonder what's going on with this outlet
temperature. Maybe my return temperature is below this 10 degrees Celsius.
So this is the central chiller water inlet node.
This is chiller one inlet.
Update graph and zoom in again.
So this green line is chiller one inlet.
And yes, it is always below the set point temperature of that of 10.
So we're not really ever turning that chiller on right here.
Yeah, it's barely, barely, barely dips above that.
So anyway, so this is a very useful way to validate the operation of a particular object or groups of objects in your model.
There is another technique within EP three that can also be quite helpful.
If I click on or if I select any object in EP three.
Once I've run a simulation, you see we have inputs, we have outputs, and these are these hourly or detailed output variables that are available for a particular object.
We also have data and there we can look at the data.
Actually, let's look at this other simulation here.
If you look at data for the boiler.
These are each the different efficiency matters that we've run this file for.
So if I look under my base, which is just, I didn't do a good job of naming my file.
But what's happening is that in order to populate this.
EP three is looking for the boiler in all of our results tables and it's going to pull out information related to the boiler.
And just give you just information related to the boiler as much as you can.
So here we have in the component sizing summary, we have some information about the boiler.
There's also some information about the boiler in the entire facility equipment summary and some of this is duplicate.
So yeah, so we have the reference capacity, we have the rated capacity, we have the efficiency.
But if you remember, we had a simulation for high our value.
So we can look at and compare the boiler capacity between the baseline.
So we have a hundred and ninety one thousand and some odd watts and high our walls and roof.
So we've saved some on our boiler size.
One hundred and eighty four thousand.
What's
a question on that so far.
When you ran, was this the model that you were using when you created these EEMs?
Yeah, so I, I simulated prior to the presentation because because the export and the simulation takes some time and we don't need to sit here and watching watching a progress bar.
So they were.
Yeah.
Can you show again how you got to that chart?
The hourly data.
If we have time. Yeah, that was really. Yeah, we have time. We've actually gotten through this material faster than I thought.
So let's start with questions that are sort of relevant to what we've talked to you today.
And then we can move into some other questions about, you know, more other other topics.
So, okay, so how do we get to that chart? So we go to view results.
And then view.
Okay, let me back up a second. If you don't have this bar.
You get this bar by clicking your EP3 logo.
And this is where you can get kind of overall settings.
Like your, if you put in your contact email, this is really useful if you happen to.
Find a bug in EP3.
You'll get a bug report form and then we can contact you and get information from you about it. We have your email.
You can set your energy plus location. You can set all of those library locations, like the internal loads library, construction library, et cetera.
You can download a weather file from website.
There are a bunch of other settings related to the building.
It's also where you get, you can change units. You can add and remove the EEMs.
You can change the names of the EEMs and you can change EEM faces. So this global settings is super, super useful.
And then you click view results.
And right here. So this is a summary.
I'll tell you each file that was, has been selected for viewing.
And then if there are detailed variables, it's right here and you click on it.
And then you get a list of all of your variables that are available.
This can be a very, very long list and it's divided based on the simulation. So this is the, this is the EEM.
And then it's telling you it's the hourly output for this.
Did you have to select these before you simulated or are there?
You do have to select these before you simulate it. So these are all node, these are all node outlets and we can set up, we can set up a new one.
We can set up some new parameters to take a look at.
I think before, before we do that, um, yeah, I'm still.
Not sure where you've got the graph from here.
Yep. Okay. So when you have your list of parameters.
I like, like, normally you'll get this big, big, long name.
I like, you can change the name here.
To make it more user friendly.
And then if you want to add or move a variable, you use these little check boxes here to, to add it to your visualization.
And then you hit update graph and that shows it to you.
And that shows all of the variables that you had listed at the bottom.
It shows all of the ones that are in bold here. So if I unclick some of them.
Got it.
There we go. Now I only have some of them.
And you just drag and drop to zoom in.
Yep, you just click and drag zoom in. And if you want to zoom out.
You double click and it brings you back to the full.
Um, the full view here.
Yeah, I spend a lot of time looking at overly details. And so this is very useful.
Yeah. And I imagine most people attending also also use the same feature.
So we can run the simulation again with, um.
With some additional hourly variables. So let's take a look at perhaps the, um.
We could look at some supply air temperatures, maybe on the air loop.
So this is this node report object. This is something that is unique to EP three.
If you view the IDF for a node report object.
What it is, is it just translates to some output variables.
So it's output variable with a key name for a node.
And then a variable name related to a node.
So if we create a new one, we could call this, um.
The.
We can select a reporting frequency.
And we can select a node variable that we want to report. So for all of the nodes that we have listed.
We will report the same variable and these are all of the different, uh.
Variables that you can get for nodes.
Nodes in energy plus are just kind of like holders of information about.
Temperature, um.
And flow rate and density. So there is a node that exists between.
They, um, so that we look at the air outlet node.
For the, this cooling coil. So right now we have the cooling coil selected the air outlet node for the cooling coil is the same node.
As the air inlet node.
For the heating coil.
So when, when, uh, energy plus simulates on the inside, like.
The simulation will tell the cooling coil.
This is the airflow that you have coming in.
And this is the temperature that you have coming in and we are requesting that you make this temperature on the outside.
And then the cooling coil will run its internal calculation and it will try to meet that load.
And it may request a different flow rate from the air system and it will tell.
Uh, it will set a state at the outlet node and it will say, this is given given the information that I have. This is what I can provide.
And then heating coil will get that information as its input.
Plus some information about what it is being requested to do. Okay. Can you meet this particular set point and it will do its thing.
And try to meet the set point.
Given the resources that it has.
So the, the temperatures and the flow rates at different nodes can tell you a lot of information about.
What is going on internally with your simulation.
So if your supplier temperature is.
If you're getting unmet loads in a space that's served by an air handler.
You can take a look at your supplier temperature and look at, okay, is that supplier temperature meeting set point.
If it's not meeting the set point.
You can take a look at the temperatures and leading up to it and see, okay.
Where are we not meeting the set point? And then you might realize that, well, the heating coil.
Isn't actually producing any heat. The temperature that goes into the heating coil is the same as the temperature going out of heat and coil.
For every single hour of the year, what's going on.
Maybe, um.
Maybe the, uh.
Maybe there's an issue with the hot water loop.
Maybe the schedule availability schedule for the heating coil was accidentally scheduled off.
There's a lot of different things, but if you, if you look at the nodes and temp node temperatures, you can start to get a really good picture of what's going on on the inside of your model.
Yeah, I've been using such tools to troubleshoot on that hours for many years like that, and it's the exact same thought process. So it is very powerful.
Yeah.
Yeah.
And here we've, we've let you create this graphically. So if we're looking at.
We can look at the system node.
System node temperature.
And then I can just click on a node.
And I get all of these little, um.
All of these little.
Circles that tell me which nodes are available for this variable. So they're, they're a lot. They're all over the place.
And then you could select.
You could select before and after the coil.
The heating coil.
Yep, you can select.
Before and after you can select any of them. The, the arrow will.
Light up when you're at a valid point. So if you click here, do anything. So you have to wait until you get a valid point.
And it will light up.
One word of caution. There's a, there's, um.
Something that happens.
If you click and you see you have all of these nodes available, if you then mouse over another note report, it will actually kind of kick you out of.
Of the tool.
We're trying to figure out why it's doing that. But if you, if you were doing this on your own, and you click, you just have to move.
Your mouse kind of around the side.
And not over these guys in order to pick up another, another point.
Yeah, we're working.
But.
So we can pick up.
It's pretty. Yeah, it's just.
Okay. And here we have a node that's located between a fan.
And a heating coil.
And it's asking us which one we want. Now, in practice right now, it's the same exact thing.
But we could.
Move.
We could move the fan.
Yeah, we could just, we could move it.
Literally.
And put another coil in between the two and the, this node would stay connected to whichever object or sorry, the node sensor would stay connected to whichever object we had selected it to be connected to.
So when those little dialogue boxes pop up.
Right, let's grab another one.
Okay.
Let's just do those for now.
We can then simulate.
We're still open to questions while this is simulating.
If this topic is relevant for other people, I'm kind of asking questions that are relevant to my experience working with a lot of customer support.
So I'm going to deselect my, my chiller temperature parameters.
And I want to see, I might just call these.
See.
I'm going to go in. I'm looking at the diagram here.
So that I can kind of call you like the AV.
123 so supply air fan or supply fan.
Outlet node.
Let's start with the
and then
main cooling coil or inlet node. So that's here.
I'm going to call that VAV1.
VAV2.
Now I need to actually click them to add them to my display.
And say update graph.
All right.
The return is 26.
And then between the return and number one, we have some outdoor air that's being mixed in.
And then it's being cooled down with the cooling coil. And it looks like we have some, if we look at the time of day up here.
Right here, the temperatures are just lining right up with that return temperature.
So here at 7am, it looks like the system switches on and it's on throughout the day.
And then it switches off again at 8pm.
And we can track those temperatures.
So we can see that the cooling coil is on.
And then between VAV3 and the outlet, it looks like there's a little bit of heat that gets added by the fan.
We can also track some variables.
By clicking on the outlet variable. So here we can track the boiler outlet temperature.
Just by clicking instead of just by selecting that, that variable at the boiler level, instead of creating a node report for that particular object.
Other questions?
No questions.
Okay.
What about we can open the, we could open the floor to completely separate questions because we've got, I think we have enough time to kind of cover something else before the end of the session.
We got through this actually faster today than I was expecting.
Yeah, well, thank you. The hourly reports are extremely important in troubleshooting.
Yeah, we also, so when you look at the hourly reports here.
And, and you can get all of this data.
You can get all of this data directly in energy plus. So we go to.
Let me just do my browsing and private it here.
Okay.
So for an example file that has already been simulated using EP launch, the result variables are available here by clicking variables.
And this will open an Excel spreadsheet that has all of the variables and all of the values for all of the variables.
In order to make any sense of this, they usually go to freeze the pains in the top rows.
And then wrap text here.
And honestly, usually make the text a bit smaller.
Otherwise it takes up a lot of real estate, but you can look at each individual.
Time series and run calculations this way, but I find when you're looking for quick feedback on a little bit of data using the EP 3 method is faster and it's a little bit easier to understand.
Yeah, you would need to plot that to make any sense of it.
Yeah, sometimes I use sometimes I use conditional formatting.
To change the colors of things and then and then patterns can kind of come out. You can actually do.
It's kind of interesting. You can do conditional formatting and then zoom way, way out and see patterns.
The each cell almost turns into a pixel.
Yeah, I just something I've never done before. So great idea.
I use conditional formatting all the time. So, yeah, I've never thought of the zoom out method where you can't read the numbers and.
And you can see patterns. So, we had a question come in a really good question. I was wondering this earlier.
Do we have the ability to get the hourly output variables in IP units.
That's a good question. I'm going to have to get back to you on that.
Okay, so homework today, I will post again to the forum some resources. So we'll share those resources about the.
The prototype building models. Somebody mentioned CB, CB and.
The energy star buildings.
The homework is going to be to add.
At least 1 detailed output variable and take a look at it.
In in EP3, so simulate a model with at least 1 detailed output variable. It can be.
It can be a note report. It can be.
Something that you have selected.
On the outputs tab. So.
For most of the objects and energy plus, you have to run a simulation once.
To generate the RDD file, and then once you have at least 1 simulation run.
If you go to the outputs tab.
For most of the objects, there will be a whole list of variables that are available.
So for each lighting object, you can get the electricity rate at a time step or hourly frequency.
For.
People, you can get an occupant talent. You can get the sensible and latent heating energy or rate. So what's and jewels are the different units.
One thing about energy plus is that you can report either hourly.
You can report at any time step annual, daily, detailed environment, hourly, monthly, one period and time step time step is a sub hourly.
So if you have 4 time steps, if your time step is set to 4, then you would have 4 time steps per hour. So instead of 8,760, you would have 8,760 times 4, you would have 1 piece of data per 15 minutes.
Detailed goes in even more detail than that, but it's not a regular chunk. So for any HVAC system variable, you will get.
Sometimes if, if the program is having trouble.
Coming to a.
Let me back up a second energy plus simulates in an iterative fraction fashion.
So the.
The output conditions from that cooling coil become the input conditions for the heating coil.
And then the output conditions from the heating coil go to the fan and then you have the whole the whole loop where we.
Run that iteration over and over and over again until.
You have basically agreement between the.
The return temperature of a loop and the supply temperature and and that every piece of equipment is kind of able to meet the load and.
And, and the, the equations are kind of resolved and it happens in an iterative fashion.
So, when the, when the calculation gets complex and it's having trouble resolving, sometimes it will go into an even like a sub hourly.
Time step.
And it doesn't happen all the time. So detailed, you'll get sometimes steps at 15 minutes, sometimes steps at 5 minutes and it bounces all over the place a little bit.
But if you, if you have a really weird thing going on, like if your energy plus model crashes mid simulation.
You should report your output variables at the detail level.
For most quality control and just verifying that things are.
Running properly, I would say either hourly or time step.
If you're running variables hourly, just be aware that.
Sometimes some piece of equipment that is either heating mode or cooling mode, say like a thermostat that has a dual set point dead band. It could be in a heating mode for part.
Of an hour and cooling mode for the other part of an hour. So if you're looking at something like.
Like thermostats, you may want to go to a time step.
Reporting frequency scale.
Quite detailed.
But yeah, that ties into a question that we just had come in.
Yeah, sure.
How much is the average simulation time for EP 3 for a typical office building compared to equest.
And as Karen was just outlining there, it's obviously not an apples to apples comparison.
And equest makes a lot of simplifications. I, I don't actually know. I know that energy plus generally takes longer to simulate.
Yeah, it does. It depends on the building. I mean, it's usually on the scale of some number of minutes.
Even with a large, really large projects, I would say, like 15 minutes from EP 3 to simulation completion.
And then you can do quite a bit to shorten a simulation.
One of the reasons that it is good to be familiar familiar with the energy plus format is that if you're troubleshooting.
And you're needing to run a lot of kind of relatively complex simulations. Sometimes it can be faster to make a very small edit in the text file, instead of having to run the EP 3 export.
Because there's, there's the export portion and then there's energy plus simulation.
So the two together can take a little bit of time.
So yeah, it's definitely longer than equest. You know, but.
I can't remember the last building I modeled that I could actually model any class. So if you take into account the simulation time and quest plus all the post processing time.
EP 3 and energy plus is much, much faster.
But yeah.
When we talk about each VC systems, I'm going to give you a bunch of.
A bunch of techniques that you can use to minimize simulation times.
So the type of equipment that you choose.
Sometimes there are 2 pieces of equipment that look equivalent and they're going to give you kind of equivalent.
Heating and cooling performance, but your simulation performance is going to be quite different.
So we'll talk about how to choose the equipment that will simulate the fastest.
Yeah, that's interesting. So again, I will create a little topic for homework for this week in the forum.
Bob and I will be monitoring the forum. So next week is mostly HVAC systems.
I think that's everything for today.
Thank you all.