[00:00:00] Speaker A: Hello and welcome to the Consulting Specifying Engineer podcast. I'm your host, Anna Steingruber and today we are talking to Tyler Mansell, PE and principal application engineer from greenheck, about Fan Energy Index. So, Fan Energy Index, or fei, is a metric that can assist engineers in selecting the most energy efficient fans for many different applications. An understanding of FEI can help engineers with code compliance and ensures that fans specified will perform with improved operating efficiencies and lower sound levels. So with all of that, I'd like to introduce our guest. Tyler Mansell is the principal application engineer with greenheck's Customer Insights team. He's been working in the industry for over 12 years with experience as a consultant, contractor and manufacturer. So, before we begin, would you like to tell us how you got into H Vac? I've heard it's been a part of your life for a really long time.
[00:00:55] Speaker B: Yeah, absolutely. So I did go to college for mechanical engineering and decided to take the career path of H Vac, which is one of the many options for mechanical engineering graduates. But before that, I had a great opportunity. As a kid growing up, my dad was a mechanical contractor. So all throughout my life, anytime I had spare time around sports in school, I was starting at age 12 washing trucks out at the shop, or insulating ductwork and threading gas pipes. So I've been around it for, for quite a long time, including obviously now post graduating and into more of the technical side.
[00:01:34] Speaker A: That's awesome. So now I think we can get into some of our more technical questions. So to begin, can you just explain what FEI is?
[00:01:43] Speaker B: So FEI stands for Fan Energy Index and it is really a unitary measure that is helpful in describing the overall energy efficiency of a particular fan. When I say overall energy efficiency, this is truly a wire to air efficiency rating of a fan component at a given duty point. So historically, you know, folks would be measuring efficiency of a fan or performance of a fan, maybe by brake, horsepower or amperage, draw, various things like that. What's great about FEI is that it takes it one step further and it includes all the components within power stream of the fan. So few examples that would include the motor itself and the motor efficiency, the efficiency of the aerodynamics of the fan design, and even things like a motor controller, so a VFD or a speed controller, for example. And historically those are the things that maybe had not been captured by the other metrics that are used in the past.
[00:02:44] Speaker A: Is FEI the same as FEG or are they different in any way?
[00:02:48] Speaker B: Yeah, this is a great question. And we actually get this question quite a bit. So to give a little bit of background here, first of all, short answer is no, they are not the same. They are very different. FEG was an initial attempt by the industry to measure a fan's efficiency, give a way to compare one fan versus another. Unfortunately, it fell very short in terms of actually accomplishing what it set out to do. So FEG or fan efficiency grade really only took into account the diameter of a fan and the peak efficiency of that fan over the entire range of its performance capabilities. So you really didn't get a dynamic report out of how that fan was going to perform.
So what that means is that if I compared two fans at a specific duty point, duty point being defined, airflow and static pressure, I might not be operating at that fan's peak efficiency. However, that's what the FEG was reporting was what is the peak or most efficient point of that particular fan. So it wasn't really an apples to apples comparison.
The beauty about FEI is a few things, really. Number one is that FEI is a dynamic rating program that takes into account the efficiency of any given fan and power system. Again, that's all the components, the motor, the drive, and the fan itself at a specific duty point. So you're going to get a different FEI for the same fan at one airflow and static pressure versus another. So we're looking at the very project specific or selection specific efficiency of that particular fan when we're using fei. And that's really one of the best parts about it, is that we know we apply these fans in a lot of different ways. So regardless of how we're applying it, we are getting an actual report out of how efficient that fan will be.
Another beauty of Fei vs. Feg is that the rating numbers are way more intuitive.
FEI looks at a baseline efficiency of a fan of a particular type. So as we look to a lot of things in the industry we're trying to benchmark in efficiency and always be improving, FEI is no different. An fei of 1.0 essentially means that the fan that I'm using in my design is exactly equal to the efficiency of that baseline fan.
If I have a fan that's got an fei of say, 1.1, I know as a design engineer that that selection I've made is exactly 10% more efficient than the baseline fan. So I know that direct proportional improvement that I've made based on my design decision, and this was another huge shortcoming of the FEG ratings, was that we weren't able to see that improvement in efficiency as a design engineer by the decisions we made, it just wasn't clear and easy to see. FEI really helps us solve this particular issue. One last thing that I would note about FEG is that unfortunately, feg, again, as a sort of a failed metric, did make its way into some codes and regulations. So in particular, it made its way into the energy codes in ASHRAE 90.1 2013 and IECC 2015.
Now, a lot of jurisdictions have actually made amendments to exclude the FEG metric, realizing that there's a better metric out there, but not all of them have. So it still may come up from time to time. And it's important for design engineers to know that there are these two metrics out there and they are very different.
[00:06:28] Speaker A: And what's the latest news in the world of commercial and industrial fans?
[00:06:34] Speaker B: Yeah, that's another great question. Just like all things within H VAC and the built environment in general, probably the hottest topic right now is energy efficiency. So that really ties in great with the FEI metric and some of these changes that are at the forefront right now. I spend a lot of my time talking with customers, whether it's consulting engineers, folks on the contracting side. And one of the things that really crops up, particularly for design engineers, consulting engineers, is that they have an inherent desire to design systems as efficiently as possible. Sometimes it's hard to keep those efficiencies in scope or in budget. Right. There's a lot of different ways that the industry is attempting to make buildings more energy conscious and energy efficient. And fans are really no different in that regard. The great thing about FEI sort of coming into the forefront now is that again, this is really giving design engineers a clear and easy metric to compare one fan's efficiency versus another for that exact instance that they're looking at. Along these same lines, we're going to talk about some of the codes and regulations that are really going to start to incorporate this FEI language into them. And these are really going to be accelerated from maybe the experiences we've had in the past. A lot of times code adoption, particularly on the energy side. So talking about actually 90.1 and or the IECC or International Energy Conservation Code, a lot of times those take a while to really take hold in particular states. But this is really gonna start showing up a lot sooner for engineers across the nation than I think we're really used to.
[00:08:16] Speaker A: Yeah, so you just touched on this a little bit. But what are some of the specific high level changes that you're seeing in the codes and regulations yeah, there's a.
[00:08:24] Speaker B: Lot really happening very, very quickly on this. So there's kind of a two pronged approach that's happening in for energy efficiency with fans. First of all, I talked a lot about ASHRAE 90.1 and the IECC. So these are the building design requirements from an energy perspective that consulting engineers have to comply with. As of ASHRAE 90.1, 2019 and IECC 2021. Both of these codes and standards have adopted language that require an FEI minimum for fans selected on those buildings.
So what that means is that moving forward, engineers that are required to comply with one of these two additions of those standards and codes are going to have to take a look at FEI and make sure that their selections are compliant.
And as I mentioned before, historically this adoption has been kind of on a state by state basis and has taken a really long time for many states to catch up. Some states are way more progressive on this than others. Examples of that would be like State of California or Washington State usually are on the leading edge of this. But what's happened also in our government is that with the Inflation Reduction act, there's been a lot of money set aside to encourage and support states in the adoption of ASHRAE 90.1, 2019 and IECC 2021 specifically. So what that means is there's money out there by the federal government to encourage states to comply with these most current energy efficiency standards for buildings. FEI is going to be one of those requirements. And for a lot of states that are maybe lagging behind several iterations, there could be a lot of other changes coming through as well. But FEI is definitely going to be one of them. And so definitely something for engineers to keep an eye out for.
The other thing I would mention that's really going to continue to accelerate the adoption of FEI is an impact that really happens on the manufacturer side. So, like a greenhack, the Department of Energy is also starting to put together some rulemakings that are requiring manufacturers like us to report and submit the FEI values of our products.
So what that means is a couple of things. First of all, all fan manufacturers are going to have to live on a level playing field when it comes to fan energy regulation and reporting out on the same metrics according to the same standards, which is good for consulting engineers, because then they know that the values they're seeing are certified not only by a third party entity, but also by the Department of Energy. Those testings and board outs are based on a third party test standard. So again, this is just a great supplement From a consulting engineering perspective, in knowing that, okay, now I've got this new building code I have to comply with. It says I need to have this minimum fei. So now I know that that means that it was reporting my fan efficiency of those products. And thanks to the Department of Energy and the federal government, I know that all manufacturers are publishing trustworthy documentation on how their fans are performing. So those are a few of the big changes that are coming through and really going to be accelerating the adoption of FEI in the H Vac industry at large.
[00:11:46] Speaker A: So when do you think engineers can expect to see FEI show up in the energy code and what are some of the requirements that engine.
[00:11:54] Speaker B: Yeah, so I would say that this is already happening again in certain portions of the nation. So we know that more. The progressive states like Washington and California, as I've mentioned before, already have language in their state specific code, their building code, to require FEI minimums. It's just really a matter of time for the rest of the states to catch up. And I think that's going to happen relatively quickly.
And as far as the requirements that are out there, because this is just starting out brand new. If we recall, the FEI measurement is a unitary measure. So the current language that shows up in the initial iterations of these building codes are saying that fans of a particular size, most often that would be greater than one nameplate horsepower, are required to have an FEI of 1.0 or greater.
So this is again really just essentially saying we want engineers. This is what the building codes are essentially saying. We want engineers to be designing around fans that are equal to or better than the baseline fan efficiency. And that's really what this metric is all about, is making sure that we're at that baseline or better. There are some exemptions, just like there are to every rule within the codes.
Most notably would be for emergency fan systems. This is something, for example, a smoke evacuation fan could be a potential exemption. And I bring that up just to kind of give the audience a little bit of understanding that is not necessarily all encompassing to all fans. I would just encourage them to take a look at those particular code sections as this starts to hit in their areas of project work and understand when they need to report this metric.
[00:13:41] Speaker A: Yeah. And so as this metric, you know, is becoming more and more common and more required, what impact do you think that it will have on design engineers specifically?
[00:13:50] Speaker B: I think this is going to be a really good thing for the industry in general, is specifically for design engineers that are laying out designs and using fans in their designs for A couple of reasons. So, first of all, as I've mentioned a couple of times, this metric just makes it very easy for an engineer to know what energy impact their selection is having on a design. If I'm selecting a fan with an Fei of 1.0 compared to a fan at the same duty point, that's got an FEI of, say, 1.2, I know that that second fan is 20% more efficient than the first fan. That's a really great sort of methodology and thought process, hopefully for our consulting engineers that are making a lot of these decisions on a regular basis.
But FEI can also represent a lot of other aspects that engineers care about when designing around fan systems. You know, historically, before a metric like this really came about, engineers may have approved alternative selections or alternative manufacturers to their basis of design strictly based off of, say, brake horsepower or maybe the breaker sizing for a particular electrical circuit. But now we have a single metric that we can look at and know that as long as the FEI of whatever fan is submitted to me as a consulting engineer meets or exceeds the FEI of the fan I selected during design, that tells me a few things. Number one, I know that that fan altogether is more efficient or is at least as efficient as my basis of design.
And with that, inherently, I know that the brake horsepower is going to be equal to or less than my basis of design. And subsequently, my breaker size will be unchanged as well. But another thing that engineers often care about, particularly with fans that are mounted indoors, is sound levels. A lot of what goes into FEI can come down to the fan housing size. One issue that can happen if you select, say, a lesser efficient fan is it might actually be a smaller fan that operates much more quickly or at a higher rpm, sort of an undesired consequence of that sometimes is excessive noise. So by having an FEI value that is equal to or greater than your basis of design, you also can rest assured that the sound levels of an equivalent type of fan will be equal to or less than what you designed around as well. So there's just a lot of positive benefits to the engineering community to help protect their design in a lot of ways. By specifying and holding this FEI value, it gives them one number to look at when evaluating these submittals, which is a really convenient thing for them during that busy time in the project workflow.
[00:16:42] Speaker A: I just have one last question for you, Tyler. So what do you think are the biggest things that engineers need to adapt?
[00:16:49] Speaker B: I would say there's a couple of things. So, first of all, I would recommend, as these code changes start to impact the areas that they do projects in. Just familiarize themselves with these various code sections that imply an FEI requirement. That would be step one just to familiarize that language. But number two is I would recommend that engineers start to specify and include FEI within their equipment schedules. So actually physically putting that number in there and as a secondary means of again protecting their design is adding a schedule note within their equipment schedules on the page that suggests that all fans must meet or exceed the scheduled FEI value. And what they're doing by including that note is they're essentially calling out that specific metric to say this is a critical metric that must be met. And then what's going to happen is they'll get selections that meet their required duty point, their airflow and static pressure, and they'll also get fans that are at least as efficient or have an FEI of their scheduled value or greater. And that's just again, going to inherently protect their design from any electrical changes, the overall efficiency of that product over the lifespan of its use. And then again, from a sound perspective, I'm really helping to dial in where that sound level is.
[00:18:16] Speaker A: Great. Thank you so much, Tyler, for all of this information and again for joining us today.
[00:18:22] Speaker B: No problem. Thank you for having me.
[00:18:24] Speaker A: And thank you to our audience for listening to this episode of the Consulting Specifying Engineer podcast. For more information on FEI or any other H VAC considerations, please visit consulting specifying
[email protected]. and don't forget to check in every other Tuesday to hear more from other industry experts. Thank you for listening and we'll talk to you next time.
