10 - Custom Load Profile

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If we wanted to modify this load profile, what we could do is export the hourly loads, and we’ll just export that to the desktop. Review my desktop; I’m going to copy this and paste it. I want to keep this one intact, because we’re going to use that one again. Alternatively, we could “Save as,” but that would require some recalculating. We’ll call it “Hourly Load 2,” we open this, and now we can do something like 1,000 tons - and let’s make this 1,000 tons every single hour of the year. 

We’ll close that, and minimize this… now we just want to go to File, and Import from Excel. Hourly Load 2. We have what we just made our changes in Excel. Of course, you could obtain this data from some sort of computer monitoring system, and you can create your very specific load profiles, and what that does is, essentially, renders all of the data that we selected earlier such as the building data and the peak loads — all of that is, essentially, unnecessary because we have the data in Excel already. We can just override that, so those first few steps don’t matter. All that matters are creating the plants, and defining the economics, of course.

We’ll save these new values, the window prompted us. Let’s go ahead and calculate. Here, we have the first two, operated at exactly the same point. When we ran this in Series, it ran at a different point, and that’s really interesting because basically, the first chiller was operating at 100% and the second chiller was operating at the remaining 400 divided by 600 tons, and that was at 67% efficiency, which changes the net consumption - and actually, operated worse because we’re adding worst operational point, at 67% of the peak load for the second chiller, versus we were at worst operational points, operating two chillers — one at 100% and one at 67%, than we were with two chillers operating at 500 divided by 600 tons, which is 83%. 

This math can be pretty confusing. I’ve done this a lot, so if we just looked though and we see that we were at approximately 83%, we were here for our first two scenarios, for every option — so we were operating at, actually, gain efficiency. In our scenario three, where we have in Series, we were operating at the exact efficiency, which was good, but then when we moved to 67%, right at this line we start to cut above, and so we start to lose some efficiency right here. From this point to, really until we get to 0, we’re operating at less efficient than we are at our 100% point. So by operating in Series, with the consistent load that is above a certain number, we’re actually hurting ourselves in that particular case.

Now, if we want to reset that load profile to what it was, just modify the load profile. I’ll import from Excel. Hourly Load Profile, the one that we saved in the first place, and here we have it. We close this, it will ask us if we want to save. Yes, we do. We’re back where we started, but we illustrated how we could edit our load profile in Excel.