TRANSCRIPT:

We'll start by talking about what EnergyPlus is, what EP3 is, and a bit about the relationship between the two.
Why use EnergyPlus versus other simulation engines?
Why is it valuable to use to learn the EnergyPlus structure instead of just a user interface?
Some strengths and weaknesses of EnergyPlus and how you can mitigate them through user interfaces.
This is a big one. EnergyPlus is kind of object-oriented modeling.
This right here really helps me understand how EnergyPlus works.
EnergyPlus is made up of individual objects that have a relationship to one another.
We'll talk about the open-source nature and release cycle and interpreting EnergyPlus structure through diagramming and a bit about homework as well.
What is EnergyPlus?
EnergyPlus is a whole-building energy simulation tool designed for modeling energy flows including heating, cooling, lighting, ventilation at a detailed level.
It's developed by the U.S. Department of Energy.
It's widely used for academic research and practical building simulations.
This academic research piece, though, this is part of why EnergyPlus can be quite inaccessible because there are a lot of modules within EnergyPlus that were developed as somebody's Ph.D. thesis
and never really used in a practical application, but it's there and it just makes EnergyPlus a lot bigger and a lot more intimidating to learn.
EnergyPlus is known for flexibility and high precision and different from some other energy simulation tools, notably Do2.
There's a coupled simulation with plant and zone loads calculated iteratively at each time step.
So this is the big reason why EnergyPlus simulates a lot slower than Do2.
Do2 is kind of like a one-way street.
It will calculate the zone loads and then have the HVAC system meet that loads and there's no kind of feedback on how the HVAC system might affect the thermodynamics of what's going on in that zone until the following time step, whereas EnergyPlus has an iterative solver for those equations at each and every time step.
Okay, what is EP3?
It's a powerful user interface for EnergyPlus and we work directly with EnergyPlus, not OpenStudio.
It's been an in-house tool since 2011.
We allow import and export of EnergyPlus objects and that import and export of EnergyPlus objects allows us to inspect all.
We are not supporting absolutely every type of EnergyPlus object, but it allows us to inspect entire and complete EnergyPlus files.
So we really encourage as a workflow in EP3 that users will import, say, an example file or a PNNL prototype building model file as a way to analyze and learn about the ways that other people have constructed models.
It's also a great way to learn about new modeling techniques and new objects, EnergyPlus object types that may be new to you.
Can I interject here just so that everyone sort of understands?
The difference here is that most EnergyPlus software uses an interface, use a layer in between EnergyPlus and the software, and so there's actually three layers to it.
There's typically this OpenStudio developers kit that you don't see, but it translates the language into EnergyPlus where EP3 works directly with EnergyPlus code and so it allows all of these additional features working directly with EnergyPlus code.
And I'm sure there's other software that can do it.
I have not seen it as done as smoothly.
So we can jump straight from the code, analyze it.
You can pick any code from any software as long as it's an EnergyPlus format and look at it.
Yes, thanks Bob.
So OpenStudio is kind of this mid-layer and it's also sort of a user interface, but it's not a fully, full-fledged user interface.
And it does have quite a few features and advantages and functions, but first of all, it didn't really exist when we started writing EP3.
I think that's the main reason we didn't use it.
However, whatever it is, 14 years down the road, I'm kind of glad we are not using it.
It adds a lot of complexity and it makes that transition from an EnergyPlus file into an EP3 file.
It would make it a lot more complex.
So yeah, so because we're dealing directly with EnergyPlus format, it means that EnergyPlus files that were created with any other user interface are viewable and manipulatable in EP3.
So TraceStudio Plus, DesignBuilder, OpenStudio, I'm trying to think, there are other ones, but all the files that are created in those user interfaces can be brought into EP3 and Minigrid in EP3.
Okay, so this is just a little drawing and this is one of the prototype building models from PNNL.
And this is actually a hospital.
So it's their Asher A90.1 hospital for New York.
And so we've taken the existing EnergyPlus file, brought it into EP3.
We kind of inspect the geometry and we can, once we have the file in the EP3 user interface, we can manipulate the file and make changes to the file and then view those changes in the IDF editor.
So or I'm sorry, view those changes in the EnergyPlus file for each object.
So here we have a wall selected.
We can see the information for that particular object.
Some of the fields are editable and some of them are not.
A lot of them have values that are auto calculated by EP3.
So some of them are, well, all of them are fields that in normal EnergyPlus you would need to fill out, but we auto calculate a lot of these fields.
And then there's a button here where we can view the IDF.
So for any object in EP3, you can always view the IDF and see what this looks like.
So EP3 is closely coupled with EnergyPlus, which means we have wide support for EnergyPlus objects and frameworks.
We can transition easily between EP3 and EnergyPlus.
It's really clean model creation.
And it's also very fast run times.
The close coupling with EnergyPlus also means that it's much easier for us to implement support for a wide, wide range of EnergyPlus objects.
Okay, so why are we using EnergyPlus versus some other simulation engines?
And this is this is quite an old comparison.
I think I remember seeing this.
Yeah, so this was from 2001.
This is quite old.
But I'm not sure anybody uses BLAST and I'm BLAST anymore, but there are some basic information on features in EnergyPlus.
But compared to other tools, EnergyPlus offers a lot of flexibility.
So it is customizable to model virtually any building system.
I think it is the most flexible HVAC system architecture out there.
I think IESVE is as good at their side systems, but not as good with water side systems.
Very high accuracy.
There's detailed algorithms validated by extensive research.
There's open source access.
So I actually made my first contributions to the EnergyPlus source code because there was a tiny little feature that I needed that wasn't getting any attention.
So I contributed something back in.
I can't remember the year, but it was EnergyPlus version 8.
It's very detailed.
And that level of flexibility makes it suitable for more complex or more innovative designs.
And there's a regular release cycle.
This is a really big one.
This is a big, big one for me.
The first couple of years I was using EnergyPlus, I actually found a bare number of bugs and they all got fixed in the next update, which was fantastic.
New features take a bit longer, but bugs they take quite seriously.
Okay, so let's take a little pause and have a discussion about.
I'd like to hear some of the people in the class what your motivations are for learning EnergyPlus.
Okay, so we have a great question going here.
Someone mentioned that they have difficulty with certain consultants and standardized results.
And the question is if they're using software that can import or that can export to an IDF file, that they can bring that file into EP3 to view it.
Yes.
Yes, that's the idea.
Now, we haven't been able to test absolutely every file from absolutely other user interface.
So please, if the file import doesn't go super smooth, send it over and we'll get it imported.
But yes, this is a big reason if you are a reviewer of models, this is a fantastic use for EP3.
Yes, and like all things, I'm sure that there are some exceptions because EnergyPlus has just this wide array of plugins and various other things.
But EP3, one of the first things I noticed about it was that it has an IDF importer.
Yeah, and when we import a file, you get two reports along with the import.
One is an error report.
So if it comes across any errors, it will tell you what they are, different things that it had trouble interpreting.
And it will give you a summary of all of the EnergyPlus objects and whether it will tell you whether or not it was imported and how it got translated into the file.
Because some things get interpreted a little bit differently in EP3.
It's minor changes, but it will tell you how everything got translated.
So you have a resource to know how and what happened with the import.
All right, EnergyPlus strengths and weaknesses.
It's highly flexible and powerful.
Sometimes we say extensively validated, open source and extensible and regular updates and bug fixes.
But sometimes strengths and weaknesses are related.
So this highly flexible and powerful also means really complex structure and a steep learning curve.
And the breadth that it covers means that some objects may be outdated or poorly documented.
And this is really common, like I said, a lot of the objects in an EnergyPlus bar related to somebody's thesis project.
And there are example files to go along with every single EnergyPlus object.
But sometimes they only show one version of the object or one type of implementation.
And the other implementations are not acting the way that they're supposed to act.
So I think it's day four.
We're going to talk about troubleshooting and how to troubleshoot and validate models.
And I'll share some techniques for verifying on a fairly fine grained scale that your model is acting the way that you want it to.
Okay, so digging in a little bit into exactly how we use EnergyPlus.
We have some common EnergyPlus file types.
EnergyPlus creates a ton of different file types, but today we're just going to talk about the most common.
So I've been saying IDF.
So the IDF is an abbreviation for input data file.
It's the primary file containing all of these simulation inputs.
In order to run a file, we also need a weather file.
So that's the EPW EnergyPlus weather file.
And that's describing the weather for a specific location.
In EnergyPlus, the input file and the weather file are actually decoupled, which for most projects is a little bit of a pain.
But it means that you can simulate a project in multiple locations quite easily.
So EP3, we take a little bit of a hybrid approach.
You have kind of one primary weather file, but for different efficiency measures, you can actually assign different weather files.
The error file, this is the text file describing any simulation issues or warnings.
So we'll dig into this more on day four.
And then we have the table output.
And this is summary results in a tabular format.
So this is where you would go to get your yearly or monthly energy use, your boiler auto sizing results, your unmet load hours, and tons and tons of other data.
And one thing about EnergyPlus is it can create a ton of data.
Okay, so, yes, sorry.
I was just highlighting here that this is input, weather, and then these are output files.
Right, where do we find EnergyPlus?
So when you do your EnergyPlus installation, the default file will be in your C drive.
And then there will be a folder that's the EnergyPlus version number.
And so you can see I have a couple of different versions of EnergyPlus installed on this computer.
Inside that folder, there's a bunch of different resources.
So I've just showed you the documentation.
And then we have EP Launch, which is sort of the main user interface for running simulations and viewing results.
I'm just so I can move away.
So documentation here, there's a lot of information in there.
That was a bit quick, but we'll get into that more detail later.
So EP Launch is the basic file management and simulation user interface that comes with EnergyPlus.
And it's great for managing simulations and viewing results.
Here we have where you select your input file.
Here is where you select your weather file.
And if you are using the EP Launch to manage your projects,
I can't tell you how many times I selected my new project file and left the weather file from a previous project
that I was working on a couple hours before or the previous day and then couldn't for the life of me figure out the energy savings.
So if you're using EP Launch, really make sure that you're coordinating your input and your weather file.
And you can simulate.
And these are all of the different output slash results files.
You can also view your IDF file using the IDF editor and the which we have a look at it.
Okay, so here is the IDF editor.
This is a pretty basic user interface for EnergyPlus, but it can be quite useful.
So over here, these are all the different, well, not all, these are where you see the different object types in EnergyPlus.
And right now we have zone selected as our object type.
Here we see the different field name and units available for each object.
Here we have the object fields and their values.
So we have a name of each zone.
And you can actually change the angle of each zone.
I don't know anybody who does that.
We get incredibly confusing.
And then there's some other geometry attributes for each zone.
Then up here, this is quite useful.
This gives a brief description of the object type and then a brief field description.
This field description actually isn't that descriptive, but here we have a description of what a zone is and EnergyPlus.
And we have this field part of total floor area selected.
And so this gives a field description for that particular input field.
So if you are working with the IDF editor, if you have questions about what an object is or what a field is,
sometimes you can get the information right here before going deeper into the documentation.
Okay, so let's simulate an example file.
So we're going to select a file.
And a weather file.
So EnergyPlus comes installed with a bunch of example files and a couple of weather files.
When we simulate, you'll see this kind of progress.
And then we click OK.
Now we can look at this in this upper left quadrant here.
These are the most commonly used output file types.
So tables and errors are the two that we talked about a couple of slides ago.
Okay, so now we're going to dive into the actual structure.
And so this is where Bob said, really be careful with the talking about IDF structure.
So please stick with me for a little bit and we'll get there.
We'll get to some more exciting stuff.
I promise it's a lot more interesting when you can see it,
which is the real value that Karen's bringing with the EP3.
However, we do need to know how it works on the back end to truly understand it.
Yeah, thank you, Bob.
Okay, so why are we learning the structure?
One is every UI, including EP3 has its capabilities and it hurts my little heart to say that.
We want to get to a point where every single file can be done 100%.
Start to finish using EP3, but every once in a while you can't.
So you can expand beyond UI capabilities.
Debugging the error file is written for energy plus.
We don't have an interpreter back into EP3 for the error file.
So when you're looking at errors, those are going to be talking about energy plus objects,
and it will help you immensely if you understand a little bit about the energy plus structure
that will help you really help you debug your files.
Platform independence, this means that you're not completely married to any particular user interface.
You have immediate access to energy plus updates.
Sometimes, especially if there's a bug that you found,
you may have a file that you've gotten start to finish in a user interface,
and you want to be able to simulate it immediately in a new version of energy plus,
and you can do that if you know a little bit about how to interact with energy plus itself
and how to use EP launch, then you have immediate access to energy plus updates for any file that you've created.
You can automate certain tasks using scripting,
but you have to know the energy plus structure in order to get that far.
You also have access to example and prototype building model files.
Now, we are giving you access to these files through EP3 as well,
but also collaboration and review of other people's files.
Knowing the full breadth of what's available in energy plus
allows you to choose a user interface that gives you access to the features that you need.
This right here is the graphic that energy plus has been using forever,
which is kind of their conception of how energy plus works.
So they have this third-party user interface wrapping the building description,
the simulation manager, and the calculation results.
So they're kind of envisioning a third-party user interface,
creating the data, running the simulation, and viewing the results.
But right here, this is the piece we're interested in,
is that direct user edits can go in right here and allow you to do things that this user interface does not.
Okay, so let's talk about energy plus components and objects.
So in energy plus, every building element is represented as a unique object.
So zones represent thermal enclosures, surfaces represent walls, floors, and ceilings,
and constructions represent the layers or properties of building envelope components.
Objects can be in any order.
There is no requirement for the surfaces that are in a zone to be listed directly under that zone.
The key concept is that objects are the building blocks of an energy plus model,
with each object serving a specific role in describing the building or system.
So here we just have a little IDF snippet of what a zone looks like.
And we created these examples, but I will say that I don't know anybody
who creates building geometry directly in energy plus.
It is useful to understand the IDF structure of building geometry
so that you can change it if you need to.
But yeah, we don't generally create building geometry directly in energy plus.
It takes like an hour to build a room.
Yeah, yeah, but I will show you an interesting example
when we talk about parametric runs about what you can do.
If you know how to manipulate this, you can do some really interesting stuff.
Okay, for this sort of separate structure, and things are relating to each other based on name.
So this building surface right here, this field zone name,
it's telling the simulation engine that building surface C2-1
is in zone two, which is right here.
So this is how objects are relating to each other.
And because we're not limiting objects to be listed directly under other objects,
it allows us to do some really interesting things with the structure.
So let's say, for example, we have a zone that's a commercial kitchen
and it's got a whole bunch of different cooking loads.
We can create an electric equipment object that represents the griddle.
We can create one that represents the range.
We can create another one that represents a deep fryer.
Another one that represents dishwasher, electric warming oven,
and we can also create gas equipment and we're not limited to the number of objects that we have.
And for each piece of equipment, we can specify the maximum load,
the usage schedule, and the portions of latent, radiant, and lost energy.
So for a zone with loads as complex as a commercial kitchen,
this ability makes determining and representing appropriate internal loads so much easier.
In E-Quest, I think we're limited to having, it's been a while, I know with lighting,
I think it's maybe two or three different lighting objects and schedules.
And these ones each also have a name so you know what the loads and schedule
and all the other properties associated with each one.
You have a name associated with it so you know what it means.
The flexible system or the flexible structure also allows multiple zone HVAC systems.
So we have a condition zone.
We can have a direct outdoor air system, a VRF heat pump, a gas-fired unit eater,
and an evaporative cooler and they can all be serving the same condition zone.
The specification for each object is independent and unique
and the objects work together to meet the zone load.
And there, I think it's day five.
Day five, we'll talk about zone HVAC objects and how to specify which order they're called
and how they share the load.
Okay, so let's get into some specifics about the properties of energy plus objects.
Actually, let me just ask for, see if there are any questions that have come up before we continue.
Questions, comments.
Input, just comparing the object-oriented programming similar to Python or Ruby,
and they said that's exactly what it is.
Yeah, I think about it the same way.
If you think about each thing in energy plus as an object,
each one has its own name, its own properties, it knows what it is
and it just needs to know how it relates to all the other things.
That's a really good way to think about it.
Yeah, so if you have experience with that, that gives you an edge on thinking like the program thinks.
Okay, so let's talk about object properties.
So we're back in our example of a zone and this is the entire definition for a zone object.
There aren't any more fields that you need in order to specify a zone.
You actually don't even need the ceiling height and the volume specified.
You can let the program auto calculate those numbers.
So each object has attributes that define its characteristic.
So this right here, this first line, this is the object type.
And then we have fields.
Over here, these are field values and they're separated by commas.
This is a little bit misaligned here, but the last field is indicated by a semicolon.
The first field is the object name.
Not every single object type has a name, but most of them do and it's always the first field.
Any text that comes after an exclamation point is a comment and is not evaluated by the simulation engine.
It's purely for a user's information.
And exclamation points followed by a dash are auto-generated by the IDF editor.
And so these correspond with the name of the field.
So if you have an EP3 generates this as well and most user interfaces will provide these same field names,
however be careful when you're editing IDF files because field order matters, this doesn't matter at all.
It's not like equest where you have a tag and a keyword that indicates what your value means.
This is just a note here.
And field order matters.
Okay, objects are...
Oh, we've got something covered here.
Objects are connected by references.
So they link to each other in two main ways.
So explicit references by name or node connections.
And we'll cover this more in the ADAC modules.
So I apologize.
You have the zone object is a little bit covered here,
but we can see that the building surface references this zone just by referencing the name.
So naming conventions are really important in EnergyPlus.
Each object is referenced by names.
And with node names, there are just more names in EnergyPlus than other simulation engines.
So it's really important to choose and stick to an evening convention.
And I kind of err on the side of really long describing names instead of short abbreviations that I'm going to forget later.
I also want to point out here that we actually have three fields in a row here.
This is an x, y, and z-coordining, and they are separated by this comma.
So, yes, we actually have three fields on each of these lines.
Okay, a well-designed user interface will handle all of these connections on your behalf.
But grasping how they function enables you to interact directly with EnergyPlus.
And it will give you all of those benefits that we talked about earlier about being able to go outside of a user interface if you need to.
And being able to troubleshoot and interoperability and all of these things.
Okay, so let's talk a little bit about example files.
So this is the description part of the five-zone air-cold example file.
You'll notice that all of this is comments, and these are explanation points without a dash after it, which means that it's a user-generated comment.
So for each example file, there'll be a description at the top that tells you a little bit about what the example file is all about and what it is meant to display.
So this five-zone air-cold, I use this one a lot, and I tend, I like to kind of stick with the same one so that, or there are a lot of sort of five-zone,
and then followed by a designation about what sort of HVAC systems are in the model.
So generally, they've taken the same kind of five-zone base building and then changed an HVAC system or changed a thermostat or added some sort of additional type of control.
So those files would just sort of small changes between the models.
Once you kind of get to know a couple of them, it can be much easier to learn from those files.
Okay, so we're going to take a look at this five-zone air-cold model in EP3.
Okay, so we can look at the building geometry, the elements, zones, plenums, surfaces that's better.
Okay, so we are importing the file into EP3.
And to add to other questions, this is the process that you would use to import a file from another software.
Yep, exactly.
So with the small model, it goes quite fast.
With larger models, it can take quite a bit longer, but it's something that happens just the first time you open a file and then once it's an EP3 model, it is there for you to use and manipulate.
So you're starting to see a little bit about the ways in which we can see and inspect the model.
So here we're looking at the same building geometry elements.
And yeah, so we've selected a wall, we've inspected it.
Just clear this.
I'm just going to let this video play again because it went pretty fast on the HVAC systems.
Yeah, so we have the building geometry outliner over here highlighting or mousing over any space.
We'll show you its location in 3B.
We have the HVAC system outliner where again, mousing over any object will show you its location.
And then selecting a particular object and looking at the selected object information, you can inspect the actual energy plus IDF for that particular object.
For a building surface, if there are windows on the wall, we will actually show you the surface and the windows together.
Questions on that?
Well, we've got a request for a special topic that we'll circle back to.
And I'm answering that right now, so I'll apologize for my typing here.
Well, let me know when you can interrupt with that when it seems...
Yeah, it's not relevant right now.
Alright, so let's talk about the tools and resources that are included within energy plus.
Okay, this is a big one. There's something called the input output reference.
And this is a massive PDF document that describes every object and input field in energy plus.
We also have the engineering manual, which explains the algorithms and physics used in energy plus.
I've referenced this from time to time. It's quite pithy, but every once in a while it's useful.
The example files, I rely on these really heavily.
And throughout this course, when we're looking at new object types, we may open up an example file,
and you'll start to get familiar with the process of referencing an example file as a way to learn about new objects in energy plus.
One of the things I'm trying to do in this course is to give you the skills to continue your learning on your own.
I'm not trying to just say, okay, this is everything you're ever going to need to learn and know about a new plus.
There's tons of more information out there, and I want to help you figure out where to go to get the information that you need.
The data sets, there's some libraries of a range of energy plus object types.
Some of them are a little bit dated, but they can still be useful for getting information.
I think the materials libraries are really useful. They have materials, data for all different construction types.
And then we already talked about EP Launch, but we are going to revisit that a little bit.
Okay, the input-output reference. So here in your energy plus installation folder under documentation.
Oh, and I have the EMF application guide highlighted, but it is actually here, the input-output reference.
And here's the beginning of information about the zone object.
So first you'll have a description of what the object is all about and the intention.
And then you'll have a list of inputs.
So yeah, so this is the object type.
And then inputs, and these are the field names. So this is just the first page of the zone information.
And then we have field descriptions.
Sometimes the field descriptions can be a bit confusing, and we encourage you to reach out to the energy plus team when you find one that is a little misleading or confusing.
Updating for the energy plus team, updating field descriptions is a pretty easy task.
And that, you know, if you're waiting a while for a new feature, yeah, I would expect that.
But generally, this is not a huge ask to say, hey, can you clarify the field description on one of these?
There's also outputs. So these are detailed outputs available for not every single object in energy plus, but most objects in energy plus have detailed outputs available.
So you can get data about, or you can get data on a time stop or hourly basis about, in this case, some of these don't make a huge amount of sense for the zone outputs,
but they do allow you to get the outdoor air dribbled temperature.
And other places, they also have the indoor air dribbled temperature for each zone.
But yeah, so they will tell you, okay, now we're talking about outputs for the zone.
They will list the outputs and then give you details about each and every one.
Yeah, so this is the outdoor air dribbled temperature calculated at the height above ground of the zone centroid.
So this will, you may get slightly different outdoor air dribbled results for one zone versus another one, same with wet bulb and wind speed.
And then revisiting the IDF editor, you can also get some information about objects from here.
And we have implemented some of that in EP3 as well.
So when you mouse over a field, it will automatically give you a little bit of information about each field.
If you want, if you find any of these to be confusing, most of these are mined from energy plus and will match the descriptions that we have in the IDF editor here.
But it is very easy for us to update these descriptions and give more information and clarity.
So if you come across one of those and you say, you know, I'd like to, I'd like to have a bit more clarity on this field, please let us know.
Those are easy asks.
Okay, the engineering manual.
This explains the internal algorithms and physics used in energy plus.
So it is in the same documentation file under the engineering reference.
And this gets into the nitty gritty physics of what's happening under the hood.
This is not a reference that I've used particularly often, but it's, it's there and yeah, it's there.
If you want to learn more about how energy plus acts and does its calculations under the hood, definitely take a look through this.
If you ever present on behalf of a career day or something, and you use energy modeling, you can mention that you use calculus every day and transfer functions and all of that.
And it's all outlined in detail in the engineering manual, and it often is overwhelming.
Some simple inputs will have the seemingly simple will have four pages of math supporting what they do.
Yeah, I mean, I quite appreciate all of the work that has gone into creating this reference and in detail and and having contributed to energy plus the level of review and an oversight.
And that that translates into the quality of the simulation. It's really impressive.
I have a lot of respect and appreciation for the energy class development team and all of the work that they put into making this tool.
Okay, so example files. The input output reference and the example files are the two biggest resources that I use when I need to inspect a new sort of area or object in energy plus.
So the example files, it's not actually showing the full path here, but in your energy class install folder, there's a folder called example files.
And that has all of the example files and some some supporting files to support the simulation and then also has these two HTML files.
This one is the one that I have open and I use the most often, but this is it on the left here is a list of every single different energy plus object.
It tells you the number of files with that object, the total number of references, and then it gives you three files that have that particular type of object in it.
So if I wanted to learn about how to model a variable refrigerant refrigerant flow air conditioner, I would go here and I would say, okay, this doix vxcoil with I'm not sure what this abbreviation means.
But I would open this file and take a look at the implementation of air conditioner variable refrigerant flow.
Some object types are better represented than others.
So, for example, a heat pump water heater is very well represented.
The example file for heat pump water heater goes through most every combination of how that heat pump water heater can be implemented.
For other objects, they may only show you one implementation of the object.
So this is a really powerful resource, but it does come with some limitations.
Okay, so yeah, this is again the beginning of our five zone air cooled example file.
So once you've chosen an example file to look at before you dig into looking at a particular object that you're interested in, it's a good idea to take a look here.
Because if this file is intended to highlight that particular object, it will tell you something in plain English a little bit about that implementation.
Yeah, and it gives a little bit of this rudimentary drawing for some of them.
It will tell you about the description of the HVAC system, zone equipment, and what they're doing for results.
So this is kind of a good place to start and get some information about what is in the file.
Okay, the data sets.
So to get to the data sets, if you go to the IDF editor and then file an open data set, there's a huge long list here.
And the one that I find the most useful is, I think there are constructions for, yeah, I think that it says ASHRAE materials.
And they have some, they have libraries that include brick and gypsum and concrete and air gap and insulation materials and glazing and all that sort of stuff.
So some of it, you can see it's from 2005, so some of it's a little bit dated, but it's a really good place to start and to see how to model different types of constructions.
And you can just copy and paste if you want a particular object.
You can copy and paste directly from the IDF editor into EP3 or into a text file.
Okay, viewing results in EP launch.
This is the tables file, and it is in the HTML format.
One of the things about EnergyPlus is that there are so many options for how you model things and also how you view results.
You can choose your preferences on what file types you want to create, which results files you want to create.
Do you want it to be in international units or imperial units?
What type of imperial units do you want?
Do you want to see the annual summary or the monthly summary or both?
So there's so many different settings in EnergyPlus about what you want to see as results.
In EP3, we have defaults for all of those things, but then every single thing is editable.
So this is just an overview of what is available in the default results file, but there is a ton of data.
Okay, so one of the things that I find very useful in understanding EnergyPlus is to create some diagrams of how objects are connected.
This is a diagram of how a zone is connected to different objects.
I find this incredibly useful when I'm modeling a new type of HVAC system is to diagram the different connections.
So we have building surface detail, which references a zone based on the zone name,
fenestration references a surface based on a surface name,
fenestration and building surface references a construction based on construction name,
and then you can reference different layers from the construction.
So we'll get into this in more detail in the future, specifically when we get to the HVAC systems.
Okay, so let's dive in to the five zone air cooled example file in EP3.
I'm actually going to close out of this slideshow and just give me a moment to open that file in EP3.
But in the meantime, that would be a good time for us to do that in a second.
And someone asked how to import the IDF file in EP3.
And so I think you're going to do that again right now.
Yeah, we're about to do that.
We are going to do that live.
Okay, and I see that most of you had been able to activate your EP3 trial license.
So that's fantastic.
If anybody has issues either access SketchUp, I know a couple of you are waiting for your SketchUp.
Extended trial licenses.
Yeah, please be patient with me on that.
They have to go through a human.
But yeah, so most of you were successful in installing EP3 and that's fantastic.
So this is our EP3 toolbar.
And we're going to import.
It is popped up on the other page.
We're going to import an example file.
Now, when you click any of the first time you interact with any of these buttons, it kind of starts EP3 and it automatically will start the wizard.
But if you don't want to use the wizard, if we want to create a file based on importing an example file, you can just close out of the wizard.
Okay, so I'm going to import an entire IDF file.
And I'm just going to browse to my example files and five zone air cooled.
And I'm just going to accept the defaults here.
The progress bars on my other screen.
Apologies for that.
But okay, let's take a look at what we see when we do the import.
So there are these two reports.
There's import errors and warnings.
So there are a couple, it's telling us that there are a couple of objects that were not imported.
And to look at the import report for some details.
So for the node lists, it's giving us a note here that node lists are integrated into the objects that reference them.
And same thing with the HVAC controller list.
Don't worry if you don't know what these object types are.
These are HVAC related objects, and we're going to get into the specifics about HVAC and meat tube.
Here is the import report.
So we have a list of the objects were given the object type, the original name, and then a true and false of whether or not it was imported and then a new object.
Name.
So some of these don't have names and they don't have names coming in.
But there's a big long list.
And then we can filter.
So we can filter by object type.
We can filter by whether or not an object is imported.
I think that it's most important to go to false and just look at each of these objects.
One of the things about energy class is that sometimes there are a million different ways to do things.
So there are one, two, three, four, five, six, seven, eight, nine, nine different ways to at least nine different ways to talk about shading and energy plus.
And each one has its own kind of geometry convention and EP3 doesn't currently support all of the different types of shading.
So that is why we see the shading object do not come in.
The other ones indicate that they're integrated into the objects that reference them.
And global geometry rules in energy plus, you also have a choice about the way you describe your geometry.
So does each coordinate in a wall, is it referenced based on a global coordinate or is it referenced relative to the zone?
We don't need to get into a ton of detail.
EP3's convention is that we use a global coordinate system and all of the other user interfaces that I've seen also use a global coordinate system is the 3D geometry math on not global coordinate system is fairly mind boggling.
We can import with it, but then we just translate it to a global coordinate system.
Okay, this is our five zone air cooled example file.
So each space, we can mass over and we can see where that space is in the file.
We have two different floors.
EP3 kind of thinks in floors even though floor is not an energy class object.
We like to break things up this way because it makes it a lot easier to understand.
The HVAC systems is, I think, where EP3 has a unique ability to display information.
We have HVAC systems diagrams and the outliner is organized by loop.
So we have a VAV system one.
This is an air loop.
We have a hot water loop, chilled water loop.
And then we can also specifically look at zone HVAC system and if there are any dedicated and assigned outdoor air nodes, we can see them as well.
Are there questions or particular objects or parts of the model that you would like to take a look at in EP3 or that you would like to inspect?
No.
I'm just giving a moment for questions.
Okay.
The first item to me is something that's really important is the fan.
It consumes a lot of energy and it looks like there is one fan here or one main fan.
Yep.
This particular model has one fan and you can also filter objects here too.
So if you want to look at and just quickly find if there are fans, you can look here.
Clicking on any object and opening the object dialogue will allow you to view the inputs for that particular object.
The fan is a relatively simple object but you'll notice that we have an inlet and an outlet that is auto calculated for us.
And when we mouse over either one of them, it shows us kind of the geometry and the location in the schematic.
Okay.
So the next step or the next task is to, but there are no more questions about this file.
We will be revisiting this file and talking in detail about what all of these different pieces mean.
The goal today is just to show you how to get an energy plus example file into EP3 and start to view it.
We can look at some of the sort of intangible objects.
So EP3 is broken down into, we have two main views.
We have the building geometry view, which we see right now.
We have the HVAC view and it was really important to us that we see the entire HVAC system in one view.
Now you don't have to switch from one thing to another to get information about an object.
The more you zoom in, the more information you get about individual objects.
So if I zoom in enough, I can see that this object is a variable volume fan and it's named supply fan one.
Now as you zoom out, it gives you a bit less information to keep the user interface nice and clean.
And then we have information about any object that is kind of an intangible object.
And there are quite a few object types available to you in EP3.
Now you can toggle between all object types or just the ones available in this particular model.
And then we can click and inspect any one of them.
So I'm going to just create a new file here.
And by interacting with any of these buttons, it will automatically generate or open the eWizard for me.
Okay, I'm going to need a little bit of user input in order to create this file.
So where in the world do we want to put it?
New York City, same thing I was going to say.
Okay, let's see what we have.
New York.
Preferably Brooklyn with a wink face.
Preferably Brooklyn. All right, and it doesn't get that specific.
But we can change some parameters in detailed mode to actually specify that it's an urban environment as well.
Okay, now we have some default internal loads sets.
So these are sets of schedules, thermostats, lighting objects, people objects and electric equipment objects that describe some fairly generic types of occupancy.
Once you work with EP3, you can also create your own internal load sets.
So if you're working with, say, hospitals or university buildings or more specific, I was talking to somebody last week who wants to use EP3 to model greenhouses.
So they have some very specific and different use cases.
And you can create your own libraries to use with EP3.
These are actually just energy plus files, they're just IDF files that have this information in them.
So one of the beautiful things about creating an IDF importer is that that then allowed us to go off and do some very different and creative things.
And the entire wizard is actually just built off of importing chunks of IDF files and applying them a certain way.
So what type of building do we have in Brooklyn?
Oh, a university building.
I was going to say office, university is great.
I think university is a great option.
Yeah, okay, so we'll adjust a little bit and we'll say classroom.
We could pull in classroom and office space.
I see.
And office space and corridors.
And I think what else?
No, and maybe, maybe assembly.
I think we could build a university building with BEMS pieces.
A conference room.
Thank you for that input.
Oh, yep.
And a conference room.
Okay.
So let's be constructions.
We're just going to bring in the ASHRAE 90.1 Climate Zone 4.
We'll bring in the non-residential constructions.
We'll create a service of water.
We'll create a standard water heater mixed object.
And then HVAC systems.
These are kind of the default ones that are currently in EP3,
but we are building more types as we go.
Any preferences on HVAC systems?
That's a pretty popular one.
Okay, nice.
That's 80.
This is...
So you need a free heat when you do that.
We can actually bring in more than one,
which we can do some really interesting things with.
I don't think we'll get to all the interesting things we can do
when we bring in more than one, but today,
because we'll get into that when we talk about parametric bonds.
Okay.
And then building geometry properties.
In this demonstration, we are going to let EP3 draw a rectangular building for us.
But we don't go into a lot of detail in the Wizard of Building geometry
because the detailed drawing mode for building geometry...
I'm going to pat myself on the back.
We think it's pretty slick.
So today, we're just going to choose a building width, a building depth,
and a number of floors, and a perimeter space depth.
So we're in meters here, which...
Preferences on size here.
100 meters by 100 meters.
I just saw that pop up.
How many floors?
Probably US, so I was thinking feet.
You were thinking feet.
Okay.
Yeah.
30 meters.
30 meters.
And number of floors.
I'm thinking in Brooklyn, a school would probably be maybe five floors.
Same as our guest here.
Oh, great.
Great.
Okay.
Let's see.
Five floors.
Okay.
And then core perimeter space depth.
I think we're going to need to go a bit more than four meters.
I think it would be closer to, let's say, maybe 12 meters.
Let's go 12 meters.
And then perimeter space.
We can make it classroom.
And the core space would be corridor.
And then we can assign some more detailed space types later.
Our guest said that 15 feet floor-to-floor.
Okay.
15 feet floor-to-floor height.
Three meters.
Four and a half meters.
Yeah.
Or five is fine.
Okay.
Great.
Okay.
So now we can modify some inputs, and this is going to take just a second, because
it's actually doing the bulk of generating the model for us.
Now, we have some internal loads, and we can modify the things like schedule, lighting,
power density.
And then this end-use subcategory is just a tag which allows you to summarize the results.
We can talk about this later, but we can modify inputs right within the wizard, if you want to.
Or all of these inputs are editable down the road.
Same with HVAC inputs.
We've kind of highlighted the most relevant inputs.
So, for example, with the boiler, we can change the fuel type and the efficiency.
And with the package terminal heat pump, we can change the availability schedule and
a couple other parameters relating to airflow and outer airflow rate.
With schedules, again, we can modify schedules.
And then, okay, let's select some default constructions.
So these are the constructions that will be used to create the building geometry by default,
but then we can change the constructions just using the SketchUp Paint tool.
Okay, let's just inspect what we have before we get too far.
Okay, so this is our very, very basic building with some pretty deep perimeter spaces and
very small core spaces.
And we have our building with a bottom floor and intermediate floor, which will have a floor multiplier.
Our top floor and each one has some classroom spaces and a core slash corridor space.
On the HVAC side, we have our boiler plant with the loop, our packaged air handler, and
then over here we have our zone HVAC, I'm sorry, our package terminal heat pump.
We connect the HVAC systems back to the building geometry by taking a look at the zone HVAC
assignments.
On the left here, we've listed each zone, each condition zone, and then we can click on
and off which HVAC object you want to have included in that particular zone.
So we could say we're going to use this VAD reheat in each classroom zone and use the
heat pump in the corridors.
Okay, and then once you have those assignments created, then your loop will kind of complete.
This is your air terminal and this creates the actual loop.
Okay, let's give a simulation a try.
All right, so it's asking us to select the energy class location.
So I'm going to navigate to my energy class install folder and then I'm going to click
select folder.
It will look for energy plus.exe in your energy plus installation folder.
And then there were some export errors actually.
Right here what it's telling us is that there are some thermostats and other objects that
are not actually being exported to IDF.
When we imported or when we created the model from the wizard, remember we brought in assembly,
classroom, conference, office building and office space and we have, or I'm sorry, the
corridor and office space, different internal load sets.
We only have zones assigned to the classroom and the corridor types.
So in this export report, it's just saying, hey, just so you know, we did not create these
in energy plus because it did not have any zones assigned to them.
Okay, and then when simulation is complete, we have the input verification and results summary
pop up.
It is actually to simulate because I'm not getting any results and we have some errors.
So I don't want to live error check this model.
We've actually created a relatively complex model here with the with HVAC system.
What I'd like to do is just give this a shot and we are going to turn off some of these
objects and just simulate with a PTAC.
So one of the things that we do with EP3 is that we want you to be able to stimulate any
efficiency measure, any alternative that you need to simulate.
We want you to be able to simulate it in the same file.
So we do that by turning objects on and off.
Basically, all of the objects stick around in SketchUp.
They stick around at EP3.
We want to export you temporarily and we don't export certain objects.
So what I'm doing right here is I'm going to take a wild guess and say that there's
something about this HVAC system that is probably not simulating.
I'm just going to turn it off and run the simulation again.
When you turn those objects off and then just assign PTACs to all of these spaces.
Okay, so now we're simulating the energy plus model.
This looks just like it does with the EP launch.
And while that's running in the background, you are free to still work with your model,
interact with it, inspect, edit, whatever you like.
When the simulation finishes, some results will pop up and we can do a little introduction
into the EP3 results viewer.
Here we go.
Okay, so this looks better.
So now we have some results available and the annual building performance summary.
This is one of the most common tables that we look at that has a summary of the energy
used for a heating, cooling, lighting, all of the kind of standard end uses that you'd
be used to seeing in any energy simulation user interface.
You can look at it in a table format.
We allow you to export any individual table to a CSV and you can also check out a graphic
or bar graph.
If you have multiple efficiency measures that you run, you'll see each efficiency measure
listed in this table or I'm sorry, in this graphic.
In these results as well, these are the different types of files that were created by the energy
plus simulation.
So there's an error file, there's the source IDF file, the tables, and then RDD and ESO
will get into a little bit later.
But if we want to inspect the IDF file, I just click on this and it's actually opened
up a key launch for me with our Brooklyn school and this is actually 2025, March 17th.
And then I can click to edit in the IDF editor or the text editor.
So here we go, any text editor here.
And this should look relatively familiar.
Let me take a look at the zone.
Okay, so the zone object, which is similar to what we have before.
Above every single object, you'll see there's a little bit of metadata in a comment where
we're storing some information, some EP3 information.
Again, this is a comment.
So this is anything that comes after an exclamation point.
The comment, it will be ignored by the energy plus simulation engine.
If you open this file, once you open this file with the IDF editor.
So let's do that.
If we open this file with the IDF editor and then make some sort of a change and save.
The format will change a little bit.
And in some cases, some of this metadata might get a little bit lost, but it's not critical.
It's not critically important.
So yeah, so this is here we go.
So we've gone from energy plus into EP3 and simulated.
And we've also created our new EP3 model from scratch and exported back to energy plus and looked at a simulation.
The homework for this class is to create your first model using the EP3 wizard and run a simulation.
And then I would like you to kind of inspect and get to know some of these object types.
So if we can take a look at, if I click on a space, I'll see information for that.
If I look at a space, I see information for that space and I can look at the IDF for that particular space.
If I click into a walls group, I can see information about an individual wall.
I can also look at the IDF for that particular wall.
I will provide you with a link to some really detailed tutorials on this.
Some of the SketchUp navigation is outlined in very good detail on some of the EP3 tutorials.
What do we have so far for questions, comments, etc.
I lost audio for a second, so I apologize if you asked a question.
Go to AirPods with Windows machine.
Anyway, we had some really good questions come in.
I'm going to ask them kind of in the order of difficulty.
So the first question that I think you can address is can we create our own constructions to save in a library?
Absolutely, yes.
So to look at constructions, it's this dialogue right here.
And there's actually a button that says create construction library for selected.
So you select the constructions you want to create a library for and you click this button.
We can speak about, we're going to speak in a bit more detail about geometry and constructions tomorrow
and specific different specific construction types.
And we'll go into more detail about that whole process tomorrow.
Okay, and if a user does not see the EP3 icons, I believe they need to go to the view menu and select toolbars.
Yes.
Yeah, so they find that here view toolbars and you'll scroll down.
You may have a couple of different toolbars that you're going to click EP3 and then that should pop up for you.
You can position it, you can actually grab it by this little bar and position it wherever you like.
Okay, and then another question that came in while we were requesting space types was about an MEP space
because of course any building is going to have an MEP space.
And I thought that it would be better to wait to ask that question afterwards.
And I have no idea the level of difficulty it would be to add that to the existing model.
Yes, so when we talk about building geometry, we'll be talking in a lot more detail about creating your custom building geometry.
And I think tomorrow's homework is going to be kind of the most time consuming because that's where you create custom building geometry
and import drawings to trace over and you specify the internal or the sort of space type of any of each particular type of object.
I'm sorry, each particular type of space.
And actually I think it's on Wednesday we'll go into internal loads.
And on Wednesday we're going to talk about a particular workflow that I have developed for managing internal loads and space types.
Yeah, so as we get to more advanced topics, it will become a little bit more central at what we're looking at.
I think there was a lot of information today because we're looking at the whole building as opposed to singular aspects of the building.
Yeah, so today we're looking at the overall energy plus structure and I hope that what everyone takes out of today is an understanding of how to just look at an individual IDF object and recognize
So this is, you know, this is an individual IDF object for a building. It has a name and an axis.
This is an individual IDF object for a space. It has a name. It's associated with a zone and we're auto calculating some geometry values.
So I'm hoping that from today you are able to identify individual IDF objects within an IDF file and that you understand the importance of why we want to be able to interact with and manipulate those objects.
Someone said I was able to take the five zone air cooled IDF open review and run via EP3 and see the results. Well, that's fantastic.
That's fantastic.
I want to thank everyone for staying interactive and keeping things engaging and asking questions.
It's been good to keep me on my toes and I really like the way that that flowed.
Yeah, yeah, I again really appreciate questions.
The more questions come in the better I'm going to be able to serve you and your goals for for your learning journey.
So I would I would encourage everyone to spend maybe a little bit of time on the forum over the next 22 hours before our next class session.
Tell tell a little bit more about yourself.
Find someone that you can work with who has maybe some some complimentary experience to you and feel free to also tell me a little bit about your particular learning goals and what you're hoping you get out of this particular class.
Our seventh session we have reserved as a special topics session.
And I'm leaving that open because I want to have time to answer your your particular questions and there's so much information available out there for energy plus.
I've gotten one question so far which is how do we model improper building operation in energy plus.
How do we model equipment that is not working properly and it's such a fantastic question.
There are so many ways to do it.
So be thinking a little bit about if there are modeling challenges that you have faced in the past that you haven't been able to to address with your existing modeling tools.
Let me know those can be well we'll see how many topics we can cover but some of those topics can be covered on our date eight session.
Yeah we did already have one that I said would be reserved for special topics.
In reality it's something that would probably take a full lesson.
And that was the question was something about how to use Python to for quality control something along those lines and scrolling through here.
And that's something that I do with equest models.
Just to find Python Python for quality control.
Can you elaborate a little bit on what this question was because a couple of ways to use Python.
I found it specifically can the training cover how to use Python to create modify and analyze IDF files.
Like I said that's a big question.
And in my experience one thing that I just use it for to analyze for text where repeated quality control is to you know search something for a term and then if it finds the number and if the number is outside of a certain range to flag that.
And this question is a little more deep than that.
Yeah so there are a lot of different ways to use Python with energy plus.
One or.
The workflow that we developed for use with EP three is.
That we try to do everything that we can with EP three and we try to make it as accessible and as quick and intuitive as possible.
If you have to stop and write a script.
A lot of my experience with with modeling buildings is that.
Each building is unique enough that I scripted.
Something that that was scripted that worked for a previous building it can be very difficult to apply to a new building and you maybe you reply the script and then you still have to make some little edits here and there.
And so with EP three we're trying to just create a user interface that allows you.
To just make the edits that you have EP three is kind of like a what you see is what you get when you switch from one EM to another the what you see in the model actually updates and changes so that you have.
Visual representation of what is in that particular efficiency measure.
Another application for Python is to.
Could you sort of in simulation modification of the.
Of.
Say schedule values or you can even override temperatures or energy use at different places in your model.
So Python.
There's Python code and then there's a energy plus specific scripting language called.
Energy management system and both of them can be used to.
Modify your simulation as it's running.
We're going to show you as many ways as possible not to do that.
Most of the.
Most modeling that I've done even really highly complex systems don't require EMS.
That's our EMS is shorthand for energy management system.
It does not require access to those.
Capabilities and.
Doing that sort of scripting inside an energy plus simulation drastically slows down the simulation.
So on day three when we talk about internal loads and schedules we're going to talk about a particular type of a particular type of schedule.
That.
When used properly can kind of replace the need for doing some of these more complex scripted solutions.
So we can talk somewhat about we can talk a little bit about scripting on day eight but we're also going to.
Cover as much as possible so that you do not have to rely on scripting.
I would add that it is text based though so anything that's text based you can probably script if.
You have some sort of background in that and that's your given would that be correct.
Yes so there.
Now all right I'm going to digress a little bit there is actually there are two different types.
Of.
Energy plus input files going to confuse the issue for a minute there is the IDF format.
And there is also another format called EP Json so it's basically a Json file format for energy plus.
And.
I don't think there is a button in EP three that generates the EP Json but we could give it to you.
If you want to script with energy plus I highly recommend.
Scripting with the EP Json format so we could take a we could take a look at EP Json on day eight.
I don't think we would go into detail on how to script with it but we can take a look at that file format because if you know scripting.
A little bit about Json it's going to be much much easier to script with that particular type of file.
And we're going to pin it to a question that's a little less intense than that.
Is there an option in EP three to have the results in IP format versus SI.
Yes there is and you can also look at your inputs in IP just by toggling right here.
Outputs and let's see to change the outputs.
So everything in energy plus is object based.
So it is.
Here's one of these output objects.
Output table summary reports.
Oh no it's a different it's a different type that I don't have here.
Outputs.
Outputs.
I might have to get back to you on exactly which object that is.
Yep here we go output control cable style.
So this is this is one of those things where in other simulation engines and even in other user interfaces some of these things might just be settings somewhere.
But we have left them as energy plus objects.
So this object right here controls the style of your output table.
We have selected that it's going to be an HTML output table and that this object is by default control.
This is created by default within EP three and then the unit conversion because the energy plus internal units are jewels.
So actually the outputs that we looked at it went through a conversion from jewels to kilowatt hour but you can choose inch pound inch pound.
If you want it an inch pound I would recommend you use inch pound except electricity.
This is what we're used to seeing where electricity is in watts and kilowatt hours but natural gas consumption is in BT user terms.
So there are a bunch of different conversions that you can use.
Okay so any other questions I am just saving all of the questions to a notepad here and we'll look at discussing them in the forum if need be.
Yeah I think we can end a couple minutes early and look for an email from me in the next few minutes that will have some links to.
I think it was just going to be one link today to a tutorial on using the wizard.
And it will give you it will it will rehash a little bit of this overview of the EP three system of the EP three ecosystem.
What's on the docket for tomorrow.
So tomorrow we are talking about building and more detail about building geometry and constructions.
So how do you draw building geometry what types of objects are available to describe building geometry what different types of constructions are available.
All of those all of those sorts of things.
Okay I want to thank everyone for the excellent questions and interaction.
Please continue to do so.
And I think that's all we have for today that was a lot because we are looking at the entire file structure.
Moving forward we're going to isolate individual paths.
Thank you everyone for your attention today with the energy plus structure I know it's you know it's a lot and it's very technical.
And as we move forward it's going to it's going to get a lot more interesting.
Yeah, especially, especially starting from day three we start to do some really interesting stuff so looking forward to it and and very glad to have all of you in the course.