Hey folks, Phil Zito here and welcome back. In this post, we are going to be looking at performing effective site audits. We're going to talk about what a site audit is, and we are going to look at seven tips that you can utilize to have more effective site audits when you actually do this.
So, what is a site audit? A site audit, quite simply, is going to an existing site with a purpose. Now typically, the purpose for us within this industry has been retrofits, although with things like I think it's State Law 97 in New York, things like Title 24 In California, things that are coming down the pipe in Washington, DC, we're starting to increasingly see site audits being utilized. They’re not so much as a pure energy audit, but as a hybrid, like identifying what building assets we have, how are they performing, and then how we can optimize them.
We see a lot of owners taking inventory of their buildings. We've gotten more calls into our organization from a consultancy perspective around that in the past couple of months than we have in the past couple of years. So, it is something that is very top of mind.
Whether it's an energy audit, or it's a kind of retrofit site analysis audit, it all comes down to the same things, which are gathering the data, identifying systems, and creating what is called a site picture. So, a site picture quite simply, is essentially like an old school digital twin. It gives you a picture of what the building is and its performance. We want to make sure that whenever we're doing a site audit, that we do it only to the level of reasonableness, based on the likelihood of a sale.
Now I'm going to repeat that but in a different way.
So, I'm sure your customers would love you to come and do a complete site audit of their building, tell them exactly what's in it, tell them exactly what's performing and what's not performing, and what they could do to fix it. But if you're not going to get any sale out of this, if this isn't going to generate revenue for your organization, then you need to know that upfront so that you most likely don't do the audit, but also, if you're doing the audit as just a favor for an existing customer, make sure you put the proper level of effort based on the return you're going to get. So, instead, if you know that a customer has a budget, then you need identify, this person has a budget so they're likely to buy, this person has buying signals, maybe they have a fund already set aside and I can put more effort into this, or this is the person who has no buying authority, has no budget, nothing. Then, you might want to consider what level of intensity you use in a site audit, if you do a site audit, even at all.
Tip #1: Grab the Live Data
That being said, let's dive into the seven tips. Whenever I do a site audit, and I've done a ton of them in the past, the first thing I ever do is grab the live system data. Now, I know data lies, and a lot of folks are like 50/50 on this tip. With that data, I look at the graphics, I look at the points, I see what's in override, I see what's up, I see what's down, I try to see if there's any trend data. What I'm trying to do is maximize the return on my effort. If I could do an export of the live data on that building automation system, telling me what's running, what's not running, get a snapshot of all the graphics, I can get a pretty good site picture that then I can utilize to verify any assumptions I make while I'm in the field. What we're going to see is, a lot of these tips require you to put forth physical effort of going into the field and looking at the individual systems. If you're able to offset that effort by getting data in the first place, it just makes life that much easier for you.
Tip #2: Read the Equipment Plate
Alright, so tip number two is to read the equipment plate. Now, this is super basic, but if you've never done a site audit before, there's a tremendous amount of information that you can get just by reading the model plate that's on the piece of equipment. What I want you to understand, and I've seen this happen quite a bit, is that people will mix vendors. So, you may have a Carrier chiller, some other type of cooling tower, and some other type of pumps. It’s not like residential where you try to keep everything the same; commercial stuff is mixed all the time.
So, the temptation for a lot of newer folks who are reading equipment plates is to assume that you have a Carrier chiller, so that means they’ll have this type of pump because they carried this product. That might not be the case, depending on the mechanical who installed this, or maybe some sort of changes that took place during the lifecycle of the building. So, you don't want to read one equipment plate and assume that that cascades to everything else.
Now, reading that equipment plate will give you several things. You'll be able to identify capacity, you'll be able to identify capabilities, you'll be able to identify potential integrations that exist. All of this, once again, is tempered by how likely the sale is to happen. If a sale is likely to happen, and it's tied to energy performance, and maybe rebates from a local utility, reading this information probably becomes important because you're going to need it in order to file rebates. If it's not likely to happen, and you're doing a favor for someone, simply saying they have this chiller, it's of this type, may be good enough.
With this information, we've taken our BAS data, what you should be building, in my opinion, is an equipment schedule. You should be building a network riser, if those don't exist. So, the equipment schedule be like an Excel sheet with the following columns:
Then your network riser should be where these controllers are, and kind of what they're controlling, and where panels are and what they're controlling.
So up to this point, we've got a snapshot of the system and we've got an idea of what pieces of equipment are being controlled by our system.
Tip #3: Check Maintenance Logs
That brings us to tip number three, which is one of my favorite tips that I didn't realize until a mentor of mine taught me this. It's to check the maintenance logs. I realized okay, check the maintenance logs, make sure maintenance has been done. That was not what he was teaching me, though. He was teaching me to look at who did the maintenance and what was the maintenance process.
So, if you looked at a maintenance chart, you could identify that the filters are changed every three months, the fan belt was changed every six months, the compressor was changed back on whatever date. Now, it gives you an idea that maintenance was done so the system is likely to be in better condition. But what you should be looking for is, who did it? Was it off site personnel? Is the facility simply run by some janitor, and then they have a centralized maintenance staff who does things, so there's no on-staff maintenance? That's going to become important later, as we look at how we can best support these customers.
Additionally, you start to understand how many of your competitors have come in and performed maintenance on these systems. That's important, because if you're going to be selling to this person, and you're doing a site audit, it's nice to know who's potentially going to be competing with you. By looking and seeing that this person maintained it, and this person maintained it, and this person maintained it, you now have three potential company competitors. You know what their products are, you should know what their general pricing is, and you should know what their go-to market strategy is so that you can mitigate those during the sales process. Whether that's mitigation through spec hooks, whether that's mitigation through how you build your architecture, whatever it is, you now have that information,
Tip #4: Grab Schedules, Set Points, and Parameters
Tip number four is to grab schedules, set points and parameters. This kind of brings us back to the building automation system, but we're going a little bit deeper. I tried to organize these things into a level of complexity, so that as you become more likely to get a sale, these are things that you can do at a deeper level. So right now, you want to grab your schedules, you want to know what's scheduled on, you want to know what set points are being used. Do they have summer/winter changeover set points? Are there resets built in? What are their parameters? What are their calibration parameters? What are their parameters for alarming and trending? This is going to give you a good picture of how the system is currently being utilized.
If you find out that everything's scheduled 24/7, set points never change, there's no resets, all the parameters are set at their default, then you have some low hanging fruit. If it's an energy play, or if it's a performance play, it's pretty easy for you additionally, and you have to make sure that you are capturing this data. When I said to make sure you capture what systems are down, you also want to capture set points and parameters. Because the old saying is, it's always controls fault, right? Well, we also want to be cognizant of the fact that who touched it last owns it. So, if stuff was never properly calibrated, there was never a good test and balance done, then these are all things that you need to be cognizant of so that you can account for them either in your costing, your exclusions, etc.
Tip #5: Identify Uncontrolled Areas
Tip number five. At this point, everything may look great. Your systems may look like they're running, your equipment may look like it's maintained, and your set points may be being achieved. But there may be some areas that are uncontrolled and uncomfortable.
We recently had our company off site and my two employees that are from the east coast were joking this morning on the team call about this place called the devil's butthole in one of the airports. It's basically this area that has no ventilation because of how it was designed. The temperature is not controlled well and it's sucking in all this stagnant air. It's just a miserable part of the airport to be in.
Now, I'm sure if we dug into that airport, there may be temperatures that are being maintained, there may be systems that are performing properly, but if you don't have sensors in the appropriate areas, you may have uncontrolled, uncomfortable areas. So, who is going to inherit that design flaw? Once you retrofit the system, it's going to be you. So always think c.y.a.
Realize that if an area is uncontrolled and uncomfortable, maybe there's an office, maybe there's a wing of the building that is southern facing and not appropriately sized for the solar loads, then you need to be aware of that so that you can address that in your scope and in your retrofit. These are things that you need to cover your butt on, because as soon as that doesn't perform, guess who owns it?
Tip #6: Profile the Energy Density
Now, tip number six, and tip number six is pretty simple. It's profile the energy density. Now, you could do this a bunch of different ways. Like, I just went and I Googled energy audit data form. If you do that, you'll get all these DoE N-rail forms, so just pick whichever one works for you. What we're trying to do here is, we're trying to understand, what is our consumption and demand per square foot, and then we want to be able to compare that to the database of buildings in a like vertical market, in our area.
What that will do is that will tell us that this building, by and large, does or does not perform well. You can have a building that looks like it's terribly maintained and just looks awful, but for whatever reason, whether it is setpoints, whether it's their sequencing, it can perform well. Vice versa, you can have a building that looks immaculately maintained, but due to the tenants, due to the sequences, due to the set points, can be performing poorly.
So, what you want to focus in on here is, overall energy density, which is how much energy, typically in BTUs per square foot. So, you'd have to convert your kilowatt hours and your therms to BTUs. You want to know, what is my density for just the general building and you want to know your density for your system performance. Do be cognizant that if you do sensors, at certain locations on the distribution of wherever the power is going through the building, you may, due to power factor, due to draw, etc, you may get improper representation of what the system is actually consuming. I've seen systems that were fed by separate distribution loops and because of that, it may look like a system is performing well when in actuality, that system is not performing well.
Now this energy density profile, it's going to help you understand that maybe these air handlers are underperforming, so we may want to look at sequencing with them. Maybe the total building’s underperforming, maybe there's a pressurization, maybe there's an insulation, maybe there's a glazing issue. There's a variety of building envelope things that may be going on.
Maybe we will find that specific areas, while they have great density, so their performance is great, but they're uncomfortable. So, we've all seen where the space is through a tenant finish out, tenant improvement, they get undersized and the space is not properly controlling to the thermal comfort that it should, even though it is efficient.
Tip #7: Log Conditional Data
Now we come up to tip number seven, which is to log conditional data. So, this is where HOBO sensors or any type of sensor that you can leave, and you can log conditional data, is going to become important. I'm a big fan of not trusting trend logs, and trusting the sensors, in any building that is more than three to five years old. After three to five years old, systems tend to have degradation of their sensors. Some places you read will say a 1% degradation per year. It depends on if it's an active sensing element, like a CO2 or humidity, or if it's a passive sensing element, like resistive or thermistor. So, I think the general rule of thumb is every five years you should be replacing your humidity and CO2 and VOC elements because they're like these little membranes. The RTDS and thermistors once you get them dialed in, they should hold steady for a good amount of time.
That being said, one of the biggest inefficiencies in systems can be sensors, because quite simply, especially if you live in a very humid environment, if you have a sensor that's off with maybe three degrees dry bulb, that can be a huge difference in relative humidity and moisture mass that is in the air. If that is what switches over your central utility plant or your economizer, then you can find yourself introducing large enthalpy loads, large moisture loads, that need to be removed from the air stream. Or you can find yourself in areas where your cooling tower doesn't have a good approach due to the improper sensing.
Which brings me to, I like to log conditional data. You may say, Phil, what data? Like, what should I log, because it doesn't seem feasible to go to an 800-bed hospital, that's a massive hospital, and put a sensor in each space in each room; that would be ridiculous. What I like to do at a minimum when I log conditional data, is I like to find the points that actually drive the switch over states.
So, if my outdoor air temp drives my switch over state from a central utility plant, if it drives my switch over state for my economizer, then I definitely want to log that with a reliable test. I used to use a kit where we would actually validate that the sensor worked and was accurate. So, you want to make sure NIST-certified and accurate. Then I would find my outdoor sensors, I would find my average valve positions if I'm doing some sort of reset there. I would find the temperatures that drive my resets. I would go to my large air handlers and get good pressure readings and make sure my pressure is accurate. I would try to get good flow readings. I’m making sure anything that tends to be a large consumer of utilities, I want to find the primary points that trigger those to change states or to enable. I want to ensure that they're accurate, and I do that with my logs.
Alright, so those are the seven tips. So, site audits, you should do them. I think we're going to see a lot of them coming down the pipe with all these regulations that the municipalities are pushing out upon building owners. I think you're going to see people wanting to get a good site picture of their building, I think you're going to see people wanting to drive energy efficient strategies in their building, and it's a good opportunity.
If you're wondering how you can get a foot into a customer, definitely, a site audit is a way to get in there. It's a way that, especially if you have a service presence, to drive some retrofit work. As a building owner, in my opinion, it's something you yourself can do as well to just get a good picture of what you have, so that you can make appropriate operational or capital budget decisions.
Now, what are the seven tips again?
- Use the live data. Grab our data, grab our graphics, do a backup, and really understand what's up and what's down. That's going to become important also, especially if we do a site audit and then we do a retrofit that simply involves putting a new head-end in and we leave the existing controls. Then someone later says the controls worked great before we did something and then we can tell them, “Well, no, actually, we have this down system list. You signed off on it saying you agree that these are down and they're still down. It's not our responsibility.”
- Getting those system model numbers and really understanding what systems are in place. At a minimum, your air handlers, your pumps, your chillers, your boilers. While I don’t think you need to get every single model number for every VAV box, you should get model numbers for anything that was engineered.
- Check maintenance logs. Not only does it tell you if stuff was done and where stuff wasn't done and what was done, but it also tells you what potential competitors have been in that building or are still in that building so you don't get blindsided. The worst thing to do is to do this great site audit, turn it over to the customer, and they hand that off to their maintenance company that's already doing work there. Then you're just like, I had no clue that this person was doing work here. Well, if you read the maintenance logs, you would have seen that information.
- Grab those scheduled set points and parameters. Those are going to become important especially if you do any form of reconfiguration. While I am an advocate of any major retrofit having functional test, point to point checkout, and test and balance redone, I do realize those are costs a lot of organizations do not want to absorb. So, at a minimum, grab those box sizes, grab those k-factors, grab those min and max CFM's, grab those prop bands, those AI values, etc. Grab those schedules, grab those alarm parameters, document them and put them back in place. Be cognizant though, if you use things like PID Loop settings or anything, and your manufacturer uses a different set of settings, you may have to reconfigure and retest.
- Identify those uncontrolled, uncomfortable areas. You don't want to be accused of those areas being uncomfortable and uncontrolled because of something you did. So, if you document that, you point out the fact that there was never a temperature sensor in there ever anyways, and the ducts to that area were disconnected, then you can either charge to fix that or you can just exclude it in your scope letter.
- Profile that energy density. Make sure you really understand what the energy density of the overall building is compared to like buildings in your market. Understand the energy density of your individual systems but do be cognizant that if you look at system level energy, it may not appropriately represent what the system is actually drawing depending where you meter; whether you meter on load side or not load side, and whether it's being fed by multiple sources or single source.
- Log that conditional data. Make sure you have that data. When I say data I'm talking in my experience, any data that drives state or mode changes. So, an outdoor air temperature sensor that drives winter/summer switchover, an outdoor air sensor that drives economizer enable, valve positions that drive a reset of pressure, temperatures that drive a reset of temperature set points, etc. You want to be logging those sensors and logging that data to ensure that that is accurate.
So, those are your tips. Lots of valuable information to use and take into account when doing your site audits. At any time if you have a question about what we’ve covered or something in addition, please reach out to me. I’m always looking forward to answering your questions and seeing what everyone is doing out in the field.
Thanks a ton for being here and take care.