Lecture: Energy consideration determined the design: Narrator: Listen to part of a lecture, in an architecture class. Professor: Okay, so as we've consistently seen over the past week, architecture's traditional approach, has often been to design first, then figure out how to make it work. So, what I'd like to talk about now, is the structure, a facility that totally reverses that mindset. For this project, engineers started out by imposing an energy consumption limit on the facility, and architects built all the design plans around that number. In other words, energy consideration determined the design. And it did so in ways that are so advanced, that the facility really raises the standards for energy efficiency. It's a research facility in Colorado. The first of its size to achieve the goal of net zero in the United States. Meaning, it creates as much energy as it uses. Let's take a look at the basic footprint. Just an outline of the foundation to start. So, you see, there are two long buildings connected at the center, forming kind of a quirk in a letter H, and these aren't typical buildings. As you can see in the footprint that's long, as well as thin. Can anyone think of a reason why that decision was made? Student1: So that there'd be more surface area for solar panels on the roof? Professor: Well, that's the right kind of thinking! Certainly, solar panels were used for this facility. They supply electricity. But, you know the shape of the building has even more to do with the Sun than just that. It was carefully designed to make an abundance of natural light available throughout the entire facility. First, the architects decided to narrow the width of those rectangular buildings. Fifty percent thinner than the average modern office building. So that light could penetrate through the many windows into the middle of each building. And secondly, they consciously positioned the buildings on the site to maximise their exposure to daylight. So the long sides get the most Sun! Student1: Hmm. Okay. So lots of light. But, uh – from what I've read, windows are a primary source of both heat loss and heat gain for buildings. I mean, how can having so many windows be energy efficient? Professor: Well, the architects use particular kinds of windows. Student2: You mean, insulated windows? The kind with multiple layers of glass and gas between each layer? Professor: Num, as I mentioned earlier, this facility sets the standard. That's old technology. For instance, throughout much of the facility, they've installed electrochromic windows. Electrochromic windows use a single pane of glass that darkens automatically and blocks out the sunlight as the temperature rises. An electric current actually changes the tint. They're placed where the building's windows gets the most Sun. Student2: Innovative. Professor: And it only gets better. You see, under each of the buildings, architects designed a broad shallow basement space, that's kind of like a maze. Air, either from within the building or the outside, is pulled into the basement space through air ducts and then forced to move slowly around concrete barriers. The air is sort of guided through the maze. Now, these concrete barriers, they absorb heat from the air if the air is warm. Or, if the air is cold, the cold is absorbed into the concrete. So it could be either way. Let's say it's hot air. Hot waste air being pulled in from the computer room say. Well, that air moves slowly back and forth between these barriers. In this particular situation then, the heat from the incoming air is transferred to the concrete. which then holds on to it. Storing the heat until later when it's slowly released throughout the building. That's the concept of thermal mass in a nutshell. Student2: Okay, so on the air, it could be hot or cold? So, then it'd be like walking into an old stone, like an old stone castle during summer time. It's so much cooler inside the castle during the day, cos the walls have retained the cold from an night air. Professor: That's right. It's precisely the same thing! Thermal mass. As a matter of fact, the outer walls of the facility consist of large panels of concrete. Merely a quick fix for that very reason. And they play a huge role in maintaining the temperature of these buildings.