11 - Internal Loads gains in OpenStudio

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Hi everyone. We talked about construction set, just now. Now we are going to talk more on the loads, the definitions. Something like, people definition, or, occupancy definition. The lighting power density, plug loads, and other kind of information, all right. Basically, they are kind of internal loads. We already have worked on the constructions, construction sets or installations, from where you get external load. Something like, what you get from the surfaces of your building. Now, let's talk about internal loads. I'll go to my, this interface, again. And, the fourth tab is loads tab. Click on it. And, you can see in this loads tab, you have different kind of definitions that you can assign. Something like, people definition, or occupancy definition. Lighting, something in density, something like in watt per square feet, or what per person, or total watts. Then you have luminaires. In case you want to provide the illuminated columns, you can totally do that. Electric equipment or plug load definition. If you have some kind of gas equipment. For example, in pantry or kitchen. Then steam equipment, or some miscellaneous ones. Internal mass, in case you are some kind of furniture, you can actually create an internal mass definition. The water use equipment definition, okay.

If you remember, when we brought those default templates based on ASHRAE 90.1 2010 for office building, it's also brought these default definitions for you. Based on 90.1 2010. Well, people definition is not based on 90.1 2010. But, something like, a lighting, is based on 90.1 2010, okay. Right now, you can see there's a lot more information. What I'm going to do is, I'm going to just purge the unused information. Let's click on this purge. Then go to lighting. Purge again, you can see it, it is trying to remove the unused information. And then, save a new copy. Save as, version 9 underscore loads. Let me just rename it properly. Save it, and go to people definition. Well, you can see for your design case, or actually, sorry. For ASHRAE baseline case, these values are perfect. You need not to make any changes.

But, what if, if you have the design case building. Well, you can make some changes, here, directly. For example, I can rename this particular occupancy, definition, for closed office. Let's say closed office underscore design occupancy def, okay. And, I can either provide a number of people, total number of people. Or, I can just provide the space floor area per person. And, let's say, it's 250 square feet per person, okay. When I made changes in the original, or the default value, it did all the changes for you automatically. This definition was assigned at space type level. Which is the most appropriate level to assign this. All those changes are reflected at the Associated levels, as well. Or, associated spaces. What if, if I want to make a copy of it, I can either create it from scratch. Or, I can just duplicate it and rename it to something like, closed office underscore design occupancy definition. I want to use this definition for one specific space. Let me just rename it to something like, conference 104 design occupancy. And, for that particular conference room I know I'll have, let's say, 20 people on max.

When you define these definitions, you basically define the peak value. They are not a time variable, okay. When you multiply this peak definition with schedule, that's when you get the overall occupancy load, or lightning load, or something, okay. These are the peak demands. You need to multiply them with schedules to get the total load, all right. Now, this load, this particular definition. Conference 104 design occupancy has 20 people. And, rather applying it at the space type, you can directly apply it at space type if you want. But, you don't want to do that. You just want to assign it for that specific conference room, 104. If you assign this new people definition to this, this conference room, here, you need to assign that load level, by the way. Here you can totally do that. If you have some additional load you can just drag it. And, drop it here, like this. And, you can see this is my latest definition, here. Where is that, this one, here. I'm sorry, this one, here. Sorry about that. What happened, it didn't change the name. Sorry, I'm sorry, I think I dragged the wrong information, wrong information. Let me just delete it for you once. It has multiple people definition.

That's good that I made some mistake. I can show you how to delete this. Select it from here, and click delete, okay. I'm going to do it one more time. In people definition, I need to bring this particular definition, conference 104. Drag it and drop it, here. Now, you can see I have this new definition, on, as an addition over the existing one. It means, that I have brought more people in my space. And, by default, it brought that schedule set that has been assigned here, in the general section, here. You can see that the schedule set has been assigned. The software is smart enough to catch that particular people schedule automatically for you. You need not to assign that schedule, again. It brought this information from this general tab. You have provided the schedule set. It filtered out that people schedule for you automatically, okay. Well, for now, I'm just going to delete it from the space type. I don't want to bring additional people load for each and every conference space. I'll go to this space tab. Take some time when you go to space tab. And, in the loads section, I look for this conference 104. I’ll just, bring this new people definition, this. And first, I will try to overwrite the existing one. Let's try it.

This is conference people. See it doesn't work. I needed to provide a new definition. I can't delete the existing one, which means I am bringing a new definition, here. In this kind of scenario. what I can do. I can just go to properties, here, in the space. And, delete this particular space type, here, directly. If I delete it, it will remove all the schedules, all the definitions. And I don't want to do that. It's a lot of work for me, right. What I can do, I can actually, either, create a new space type. You know, it's much easier. Or else like, just like, do all the things like, from scratch. Let's just like, you know, work on like, you know, bringing all the things from scratch. I'm going to delete this space type for this particular conference room, okay. Let's just delete it. You can see there is no conference space type assigned to this conference 104. The schedule set has already been assigned, which is a good thing, okay. This is not connected to space type, here. This conference room has its own schedule set, which we assigned in my, in maybe like, half an hour back.

Go to loads, now. And, you can see this conference room has only one definition, which is people definition, okay. We need to bring something forward. Lighting, the infiltration, and plug loads. Let's say, like, let's rename it to something like, I mean, this is also fine. But, I want to, I always like to rename my things properly. Something like, conference people load. And then, I can bring something for lighting from my model. Or, from library, either way is fine. From my model, if I look in lighting definition and look for conference room, this one, assign it, here. And, it will bring this schedule automatically. I can rename it something like, copy this, put pasted here, and rename, here. And same thing for plug loads. And, let's just assume that you we have plug loads. Like, something for computers, or projectors. As well as, there's some fancy fish tank, okay. Let's just, like, you know, create something new, here. In electric equipment, I'm going to bring something for conference, as well. Drag and drop. We are using the existing definitions, but in a different ways. We are assigning all the properties directly at space.

Let's just rename it, again. Load, okay. And, you can see, you already have the plug load equipment schedule. And, let's just create something new, now. I'm going to create a new plug load. Let's say for fish tank. Electric equipment, create a new thing, fish tank, load definition, actually, okay. And, just assign the peak design level rather than assigning some kind of density. Because, this fish tank, let's assume that the fish tank is 200 watt. And, that runs 24 hours. We need to create a new schedule. Go to schedules. And, create something from scratch. Fractional one, apply, rename it to fish, or, let's say, 24 hour schedule. And, assign 100 person fraction from 12 a.m. to 12 a.m., all right.

Now, go to this space tab, again. And, in loads, go to my models. In plug load definition, here, where is that. This one, here, look for fish tank, assign it here. And, you can see, because we have assigned the constructions, I'm sorry, the schedule set, here. Here, it automatically brings the schedule for your fish tank, as well. Well, you want 24 hours scheduled, here. We need to update this one, as well. Go to rule set schedules, and look for this, 24 hours schedule. Drag and drop here over fish tank, okay. This fish tank definition is running for 24 hours. It's a new load. Let's just rename it, fish tank load, all right. And, save the model, okay. We can assign some more stuff here in this conference room. For example, what if, if we had two lamps, table lamps, here. Some additional lamps later, what, like, you know, the tenants brought with them.

Go to luminaire, create plus sign.  Let’s just assign table lamp. Lighting power, let's say, 100 watt. You can provide some fraction radiant and fraction visible information. I'm not worried for this one, now. It just basically, like, you know, define more information. How much return air fraction will be there from this particular luminaire, or something. In case you want to read more on this, you can just go to EnergyPlus documentation. Remember, like, I explained to you how to get that EnergyPlus documentation earlier. Look for this term. Go to this documentation. And, in this input-output reference, look for luminaires. There’s like, a PDF, you can just download it easily. And, if I just do a ctrl F, which is to find the words. Let me, let's just, like, you know, let it just finish everything. I mean, while I can just like, provide some information. Table lamp is fine. They have a particular schedule. They just work from, let's say, 5 p.m. to 9:00 p.m. Go to schedules. Let's create something real quick, which is going to be fractional one, apply.

I know, let's provide something like, table lamp schedule. And, they just work from 4:00 p.m. to 8:00 p.m., let's say. So, 100% from 4:00 p.m. to 8:00 p.m. Go to spaces, go to my model, look for that luminaire definition, here, here. Assign it here. Automatically it will bring something for you, the conference lighting schedule, but you need to override this. Go to my model, again. Go to rule set schedules. Bring this new lighting schedule that we created for table lamp, this one. Drag and drop over this new definition. And, rename this luminaire load, as well. Table lamp, oh my god, lighting load, okay. All right, and save the model. I can go back to my internet explorer. And, you can see if I like, do a real quick search for luminaire, I need to work on my spellings. Let me just see what is the spelling for luminaire. It's, L U M I, okay. L U M I N, L U M I N A I R E, okay. And, hit enter it will bring all, like, you know, it will such everything for you. What you can do, you can just go to that particular search, I think there's something wrong with my word, here. It will search all, everything for you, if you keep going. You can read more on this.

For example, this is like, written air fraction information and everything. You can read through this, and you can understand what is happening when you provide some values for it on the infraction, all right. Please don't forget to use the input-output reference, it's very important. Now, once you are done with providing some information, just, you can the run this simulation. And before I run this simulation, I want to check my, check my notes, again, if I forgot something. In people definition, you can see you need to provide some fraction radiant, sensible heat fraction, it's automatic for, auto calculate, for now. I would keep it like this. In case you have some properties, you can update it. You have some more information like, internal mass, other equipment. Let's just create something like, internal mass, some kind of furniture. Click the plus sign. Let's rename it to something like, piano. We have a piano in our office. The surface area, let's say it's, I know, 20 square feet. And, surface area per space floor area, that should be all right. We have provided surface area. And, construction we can provide a gypsum board construction, for now. The piano is made of gypsum board. You can just create something new, I think that, that's more appropriate.

I go to constructions, here. In construction, click plus sign, and rename it to piano construction. And you can assign this gypsum as the material for now, okay. This piano here, go to my model, look for half-inch gypsum, all right. Basically, we are bringing some kind of thermal mass in our space. It will definitely impact our HVAC related loads. And, I will explain on this later, when we move to HVACS, all right. Click on this, load section, again. Go to internal mass, and assign this construction, this one. And assign this construction, or, actually, this internal mass, directly at the space section. Let's say, that conference room also has that piano. Look for that internal mass, and assign it, okay, that's it.

And, you can see, this piano, it doesn't need to have some kind of, any kind of schedule. It's already there. I mean, you can't just move that piano based on any kind of schedule, all right. This kind of furniture or anything related to thermal mass, or, internal wall, comes under load, as well. If you go to this load section, again. You can see, you have other kind of stuff, as well. Something like, water use equipment. Again guys, I don't want to explain to you this water use equipment right now. Because, you will get confused. I will explain to you the water use thing when we jump to domestic hot water loop, okay. Don't worry about this. I will explain to you everything from scratch, even for water use, all right. Save your model. And, you can run this simulation, here, okay. Just run it.