35 min read

🎧 #107: Balancing Embodied and Operational Carbon Emissions

“As we draw down the operational carbon side of things, our embodied carbon piece of the pie is going to be closer to 50% of overall carbon emissions from the building sector."

—Carmel Pratt

Welcome to Nexus, a newsletter and podcast for smart people applying smart building technology—hosted by James Dice. If you’re new to Nexus, you might want to start here.

The Nexus podcast (Apple | Spotify | YouTube | Other apps) is our chance to explore and learn with the brightest in our industry—together. The project is directly funded by listeners like you who have joined the Nexus Pro membership community.

You can join Nexus Pro to get a weekly-ish deep dive, access to the Nexus Vendor Landscape, and invites to exclusive events with a community of smart buildings nerds.

Episode 107 is a conversation with Carmel Pratt, Director of New Construction at Bright Power in NYC.


We talked about embodied carbon emissions and how leading construction teams are balancing embodied carbon with operational carbon emissions over the life of a building asset. Then we zoomed in on the operational side and I got Carmel’s take on the challenges ahead in electrifying our buildings.

This was super insightful, enjoy!

  1. Bright Power (1:05)
  2. The Levy Partnership (1:33)
  3. Steven Winter Associates (1:37)
  4. Twiddle (5:29)
  5. Mihali (5:29)
  6. Umphrey McGee (5:52)
  7. STS9 (5:52)
  8. Nexus Podcast with Stacy Smedley (8:50)
  9. Architecture 2030 (10:53)
  10. Passive House Institute PHPP (16:12)
  11. Sara Bayer (22:03)
  12. A Delicate Balance: Weighing EC vs. OC, Part 1 & Part 2 (26:38)
  13. After Cooling by Eric Dean Wilson (47:01)
  14. The New Carbon Architecture by Bruce King (47:52)
  15. Healthy Buildings by Joseph G. Allen (48:13)
  16. The Passive House Excelorator Podcast (48:39)

You can find Carmel on LinkedIn.



  • Bright Power (6:18)
  • How to think about what percentage of a building owner's carbon footprint is operational vs embodied (8:58)
  • How to balance embodied carbon and operational carbon (20:14)
  • Key takeaways and ways the industry needs to change (29:34)
  • Carveouts (46:45)

Music credit: Dream Big by Audiobinger—licensed under an Attribution-NonCommercial-ShareAlike License.

Full transcript

Note: transcript was created using an imperfect machine learning tool and lightly edited by a human (so you can get the gist). Please forgive errors!

[00:00:03] James Dice: hello friends, welcome to the nexus podcast. I'm your host James dice each week. I fire questions that the leaders of the smart buildings industry to try to figure out where we're headed and how we can get there faster without all the marketing fluff. I'm pushing my learning to the limit. And I'm so glad to have you here following along.

[00:00:31] James Dice: This episode was a conversation with Carmel Pratt, director of new construction at bright power and NYC. We talked about embodied carbon emissions and how leading construction teams are balancing embodied carbon with operational carbon emissions over the life of a building asset. Then we zoomed in on the operational side and I got Carmelo's take on the challenges, had an electrifying, our buildings. This was super insightful. Please enjoy.

Hello, Carmel. Welcome to the show. Can you introduce yourself, [00:01:00] please?

[00:01:01] Carmel Pratt: Thanks. Yeah. I'm Carmel Pratt vice president of new construction in New York at bright power. I have a background in architecture and a passion for sustainability, and I lead a bunch of teams at bright power that provide consulting services in the energy efficiency and sustainability space for ground up new construction projects, as well as rehabilitation projects mostly in the five boroughs of New York.

[00:01:25] James Dice: Cool. Can you tell us about your background before bright

[00:01:28] Carmel Pratt: pal? Yeah. So prior to joining bright power, I was the sustainability director at the levy partnership. And before that I was a sustainability consultant at Steven winter associates. And before that I was installing installation at habitat for humanity in Patterson, New Jersey.

I have been working in this space for a little over eight years now. Again, managing teams or managing projects directly that are pursuing certification standards, green building certification programs, incentive programs have [00:02:00] done everything from, like I said, installing installation to doing inspections and performance testing.

Post-completion do a lot of design reviews and energy modeling and general consulting in this case.

[00:02:15] James Dice: Tell me about what installing installations like w what, what is that like day to day?

[00:02:22] Carmel Pratt: Yeah, so it's you know, I always tell people, like, if you get out in the field and you see where the rubber hits the road it really starts to connect the dots.

And so I think that was the kind of beginning of, of my passion of understanding that what you can theorize, you know, with. Academic background in architecture is, is not always what happens in, in, in situ, right. When you go to install a bead of caulk and you're trying to connect wood to a fiberglass window, for example there's a lot that goes into that.

So I say installing installation, actually, it was a lot of like weatherization work. So air sealing as well. And I, I managed [00:03:00] the the energy star certifications and the overall. What was called like green services or energy efficiency of habitat builds. So, I was, I was doing the work.

I was also teaching volunteers that had like zero, skills in terms of manual labor skills to to do air ceiling and installation work that had to be, have a higher caliber because we were getting. We were getting inspections from an energy star and hers rater.

[00:03:27] James Dice: Got it. So I have a selfish question.

I'm thinking about doing sealing my house. My house was built in 1959, thinking about basically doing all the installation and weatherization myself. What do you, what do you think about that?

[00:03:40] Carmel Pratt: I think if you're thinking about fiberglass cover your body, head to toe knowing stuff to, to work with. And and also, I just wouldn't recommend it as a, as a product.

And, and we'll talk about that, like later in this conversation, but for various reasons, one of them being the embodied carbon impacts of fiberglass as, as [00:04:00] a material. It's not fun to work with or breathe in. Definitely, wear a respirator respirator if you do plan on using it. But. It's definitely humbling work.

And I, I, I think it's totally possible for someone to DIY it. If they have the time and they really put in the effort to, follow manufacturer recommendations for installation it's the type of thing where you can get a really good product, but if you don't install it correctly, it's not.

Work in the way that it's intended. So depending on, I dunno if you have thoughts already on what material you want to use and what kind of, air ceiling materials and techniques, but it's definitely something you want to give yourself enough time to do correctly and and kind of do it once, right.

And not have to worry about it again.

[00:04:48] James Dice: That's helpful. We won't go down that rabbit hole, but that's very helpful. So I was stalking you online and saw that you asked, you got to ask in an interview. What do you want to be when you grow up? And you said an [00:05:00] architect or a jam band, singer and architects.

Normal Dan banned cigarette. I'm wondering I'm at fellow jam band fan. What jam bands do you like, or did you like back then?

[00:05:12] Carmel Pratt: I'll just argue for a second that an architect being normal over jam 10 seniors, like for the fog dependent, dependent on like your situation and you know where you are in life.

But I followed, I guess most recently, like twiddle and Mohali, which are, I guess, more local to our east coast. Um, Yeah, I'm not a fish fan. Sorry guys, but just not, not my thing. Yeah. More just local local bands and, and, people that I can just pick up and jam with myself

[00:05:48] James Dice: Very good. I very much followed Umphrey's McGee and soundtrack sector nine throughout college saw them both many, many times. I think those are in the Jan band [00:06:00] category. Am

[00:06:01] Carmel Pratt: I right? I don't even know that I know what would fall in or out of the January category haven't heard of, of those two that you've mentioned.

So I feel like. Yeah. To teach her own and maybe very geographical. Alright.

[00:06:17] James Dice: Alright, cool. Well, let's jump in. So, bright power. Can you tell us more about in general what, what they do as a

[00:06:24] Carmel Pratt: whole? Yeah, so, in general, bright power is a energy and water management partner. We. Have a whole arm, but we've been around for about 16 years.

Started in New York spread to have a an office in Oakland, California, as well as a lot of kind of salad, satellite people in offices across the globe actually now and definitely doing work nationally. Started out doing a lot of existing building auditing, and then moved into the space of utility analysis and like ongoing monitoring of energy and water in [00:07:00] buildings and created a whole.

Online platform for for utility monitoring called energy scorecards. So we have a lot of clients that subscribe to that for utility data, aggregation and analysis, and kind of ongoing monitoring. That is admittedly a whole side of the business that I'm sure. Way less involved in and in the know of but that is, in terms of the, the folks out there that are interested in data and technology we do, we provide a software product and a service through that.

My side of things is a lot more kind of in the consulting space in the project design and construction kind of, Like I mentioned before, everything from boots on the ground inspections and performance testing to design consulting, energy models. Building commissioning both on the existing building side, as well as on the new construction side.

And in the New York office specifically we also have real-time energy management which is [00:08:00] like, a bunch of engineers that go in and put sensors and information of, of, you know, things kind of tech that gives real time feedback. Um, And they're monitoring, kind of, abnormalities or things that are going on in the building and giving feedback to the building operator or owner to try to, to draw down energy and why.

[00:08:21] James Dice: Yeah, by the time this podcast gets published, we will have had someone from NYSERDA coming on to talk about the art program right before this. So, great,


[00:08:30] Carmel Pratt: timing there. Awesome. Yeah, that's that's our, our big partner in that work and really how a lot of those projects are getting funded right now is through, I started as our Tim incentive programs.

So. Cool. Yeah.

[00:08:42] James Dice: So we're going to, we're going to not talk about that side of the business that you're not involved in. I want to jump in and talk about. So we had Stacy Smedley on the podcast. Last summer, I think it was to talk about embodied carbon. We haven't really revisited the topic since then.

So I think it'd be a great opportunity to [00:09:00] dive into that with you. The place. I think it'd be fun to kick off was what we were talking about this before we hit record, how to think about, if we think about an organization, a building owner organizations, carbon footprint. What percentage of their building footprints is operational versus embodied?

I know it's, it depends right at the engineer's favorite answer. It depends, but like, can you talk about what goes through your mind there and what, what does it depend on? How do we sort of get to a general conceptual understanding? What's in what bucket?

[00:09:32] Carmel Pratt: Yeah, I think where we have to start is agreeing on how we frame kind of where we start and stop the ticker at that we're that we're calculating, you're adding up embodied carbon and operational carbon.

So that that's the first place is like, are we looking at every piece of material From its extraction through to when it comes on site and its afterlife is that the full lifecycle that we call it of, of that [00:10:00] product? Or is it just, From, from what we call gate to gate, which means the moment that it comes on site versus, where it came from beforehand.

So, it's, depending on how you cut that the, the, I guess, the percentage can, can change drastically. And the other factor in that framework is time, right? So where do we cut off? How long we are. We are monitoring the operation of a building or how long that building is going to be online and expending energy.

The reason that embodied carbon is so important right now is because if we look at that time before. As a shorter, 10, even 20 year timeframe. The the, I guess Seesaw, the weight of embodied carbon is a lot heavier than the operational carbon. If we're thinking about a building being online for a hundred years, so.

Architecture 2030 which Stacy from Kansas is very involved in and the carbon leadership forum have tried [00:11:00] to put together framework for, putting a number to this and getting this kind of urgency. Around the timeframe where they see that in the next 10 years. As we bring down, as we draw down the operational carbon side of things, our embodied carbon piece of the pie is going to be closer to 50, if not more percent of overall what we consider to be building emissions, carbon emissions from the building sector.

So. When you put that timeframe on it, that's where the urgency comes in. And that's where the percentage and the amount of embodied carbon actually skyrockets. Because now we are looking at a longer life stage of the products that go into the building and a shorter timeframe for what we consider to be the operation of the building.

Right. It takes. To maybe years to put a building up. And then it is up for a hundred years, but how much carbon went into a very short two years that went into building that building.

[00:11:58] James Dice: Right? So if I'm [00:12:00] drawing like this box around both right? The building of the building and the operating of the building, the shorter, I make the operational phase, you're saying if we're drawing maybe a 10 year window around the operational phase, That means the embodied bubble is much bigger as a relative part of the whole et cetera, you're saying.

Yeah, but if we draw that operational out a hundred years, the operational carbon ends up swallowing a lot of the embodied carbon,

[00:12:29] Carmel Pratt: depending, depending on what the weight is of whatever you're looking at, calculating embodied carbon for. That really all of these questions is what turned into a little kind of passion research project that that myself and M and a partner Aquatech started to get into is like, how, how are we calculating both these things embodied and operational carbon.

And then what does it look like when we, put a 10 year timeframe on it versus. The lifetime of the building. And [00:13:00] where, where then can you pinpoint the point, the point in time where where that shift in the weight of carbon on the embodied side versus the operational side, actually, like I said, shifts the, the Seesaw sort of over to the other side.

Got it.

[00:13:18] James Dice: Anyone that's out there saying. One is the more important than the other though. If we look at the big picture to that question, it's it just depends on those couple of factors. You mentioned. There's no one answer


[00:13:29] Carmel Pratt: this point there isn't balancing the two is important, but I would say for where we're at right now, in terms of, our 1.5 ºC over our global carbon emissions, the urgency is in the timeframe, right? Like we don't have a 100 years that a building's online to, to kind of get our return on investment in what we're putting into the building. Now we need to look at what, is this in the next 10 [00:14:00] years? Because we can't.

get Another degree Celsius above our carbon expenditure globally. So, so when we look at it also, when we get to zoom way out, forget the building, look at the planet and what, do we have in terms of, that equation in carbon expenditure, that, also begins to highlight the importance of, the embodied carbon.


[00:14:24] James Dice: Got

it. So how do you balance the two then? What does that even mean? I guess, to begin with?

[00:14:29] Carmel Pratt: Yeah, so, that means asking these questions, looking at every single thing that goes into the building I'd even argue like the transport and the energy used in making the decisions of what goes into the building.

And, and looking at these things and deciding. Where it makes sense to Here's an example. But at what point if we take the roof, for example, at what point. in the increase of installation at the roof where we're potentially [00:15:00] adding, a bad material like plastic foam to get a better thermal performance on that roof.

At what point do we have diminishing returns, operationally where we can never buy back the carbon of two additional inches of, plastic foam installation. And so that's where you start to balance thinking about long-term operation of the building. Are we really in a 100 years going to make back the carbon that was expended in that two inches of plastic foam that we added to.


[00:15:32] James Dice: So what's that analysis look like on a new building or an existing one? It sounds like it's a lot of like what Stacy talks about these different. Material models. Right. And then there's on the operating side and energy model that you can then unite the two into some sort of decision support system or whatever.

However you want to call it. How does that, how does that work in practice?

[00:15:57] Carmel Pratt: Yeah, so, I and I, an [00:16:00] ideal state we would marry the two and simultaneously be. Calculating and tracking. Embodied carbon and operational carbon in real time. And actually I'll shout out the passive house Institute Phi energy modeling software, which is called PHPP.

They came out with a a new like plugin. They call it the passive house network ribbon. And it's a plugin for the software that actually. Pulls the material emissions database from the, the work that Stacy was involved in, in the um,, which is the building transparencies. Like it's a, it's a database of EPDs environmental product declaration for a bunch of products.

And it pulls that data along with EPA emissions data for like sourcing energy and other things right into your energy modeling software. So, yeah. Simultaneously calculate all this and see, in real time that Seesaw and the levers going up and down with [00:17:00] different, different material use and and different design strategies that you're, you're working with.

We in our study had to do this a lot more manually. We were not working in this ideal state in that software. It just recently came out. So, we're excited and are starting to pilot it. It's pretty new new to us. So what we were doing is we were manually pulling data from that tool, as an example.

Just calculating volume of material, whether it be cement or roof installation or whatever it is getting a carbon equivalency number. And we had a spreadsheet going where we were plugging in on one side, the embodied carbon calculations from an outside tool, like and then had an energy model.

Right. Kind of at the same time where we were making those changes, whether it was increasing insulation or changing the material and then plugging that into our spreadsheet and kind of comparing things, manually old school. [00:18:00]

[00:18:00] James Dice: I think anyone that grew up in the days of Excel based optimization, we've all done the sort of manual iteration.

Hopefully there's some sort of software that's what machine learning is supposed to be able to do at some point is to optimize these things for our spirit, essentially optimizing for both at the same time as what we need to get to as what you're saying. And it sounds like if you don't, you could be solving for one of them at the expense of the other, like you're saying.

I had a really high carbon dense installation you're solving for the energy, the operational side, but you're not solving for the, the embodied side. Is that happen a lot today?

[00:18:38] Carmel Pratt: Exactly. Yeah. It's in the last 20 years there was this huge movement and push on the operational carbon side and with, passive house in.

On the very positive side, passive house created these super insulated homes that, allowed us to downsize our mechanical equipment and have very low heating and cooling loads, which is great [00:19:00] operationally. But we threw in a ton of material to do that on, on a building. And so we, we were doing that we've been doing that are continuing to do that for, how many years.

So at this point it's kind of like, taking a step back in what we've been focused on, which is the operational carbon side. And and really, your question about like, where do you find that balance? It's important to create, again, a framework of like passive house gives you a nice framework of targets to meet for heating and cooling loads for overall site energy.

And so if you're still within those targets and you're, you're meeting the passive house intense, that's a good framework to say, okay. Like we're we got here. Yeah. With, with a little bit of renewable energy, we can get to net zero with this design. We don't have to add more installation just cause it's going to bring down the heating load a little bit more, we, we can make that up.

And as we clean up our grid and as we clean up our electrification, [00:20:00] like our options for electrifying our mechanical systems we can get to a. That's zero, zero seats scenario with out just like over insulating and over over engineering of building.

[00:20:14] James Dice: How does this, this thought of balancing ISI and OSI?

How does this apply to existing bills?

[00:20:21] Carmel Pratt: Yeah, actually, an argument is that like existing buildings are the best place to start when you're looking to to, bring down embodied carbon um, use what you already have. Right. So, The most amount of embodied carbon is typically spent in the superstructure of a new building.

So that's, you know what there is cement or mass timber or whatever it is, or even, wood-frame buildings. You have a lot of expenditure there. So, if you can use the good bones of an existing building off the bat, you're cutting out a lot of, embodied carbon of new material. And, and, there's existing buildings come with [00:21:00] all of their own issues and tricky conditions.

And sometimes there are limitations to what you can do on the interior versus the exterior, for example, on the envelope. But it is, definitely general sentiment is the more you can reuse in a strategic way, the, the lower, your, your embodied carbon. Number is going to be

[00:21:22] James Dice: okay. Cool. So tell me about the study.

Can you talk about how it, how it came about and who funded it and all that?

[00:21:31] Carmel Pratt: Yeah. So, this study is on a project, a development in Brooklyn, in New York of two buildings that are affordable housing mid-rise buildings, like 35 to 40 units. Each building there situated across the street from each other.

And the The, the owner and the architect and ourselves we're always pursuing passive house certification for these buildings. But the the architect and I'll, I'll [00:22:00] shout out my, my true partner on this study, which is Sarah Bayer at in architecture and planning The architect and myself both came from this kind of like personal passion interest in nobody, carbon and decided halo.

Let's really look at this on this building. How can we fund some of the time that's going to take, to do these calculations? And so those buildings applied for an award through NYSERDA, we will, you'll speak to in, in a couple of weeks, it sounds like they had a competitive solicitation of.

Program called buildings of excellence. It was it's now in its third round, it was at its second round when we applied with these buildings. But. It essentially funds the type of technical assistance that goes into designing low carbon buildings. It also intends to fund the gap that might be in in the cost of, upgrading.

Envelope or other building systems to get to that low carbon target. And in this case, our [00:23:00] application really highlighted the work that we wanted to do in looking at the embodied carbon side of things. So, that, that award money kind of went into this. Kind of time and just, passion for this has gone into that.

And yeah, like I mentioned, so the the architecture partner map um, Sarah buyer for the most part was looking into doing the calculations in terms of getting, like I said, the volume metric kind of numbers from whatever they were specifying for different components of the building.

And we were. In the background, making all of the adjustments kind of in real time on the energy model. Every time we tweak something, one way, change a material, whatever it was and giving that feedback. So, yeah, it worked really nicely that, that we could partner in that way and kind of each take a piece of the, of the calculation of the pie, so to speak.

But what we're looking forward to now is having that capability in. Software, like [00:24:00] I said, to be able to do that calculation, one person could be getting all that information and inputting it and and outputting some useful information to, to make decisions.

[00:24:12] James Dice: Cool. So what was the intent of overall intent of the study and then what did you find from

[00:24:17] Carmel Pratt: it?

So the intent was just to really draw down wherever possible embodied carbon and just to understand what the weight of it was. Right. We knew that we needed to meet the passive house targets. So like that created sort of, Walls for us to stay within and bounce around. And within that, we were just free to like, Look at alternatives for materials see where we could, like I said, reduce, you know, roof installation or wall installation or whatever it might be play around with triple versus double pane windows and, And yeah, and, and that was the intent there is to see how low can we get embodied carbon and still hit passive house goals and still show this [00:25:00] nice low operational carbon, low site energy use intensity with a significant reduction on the embodied carbon side.

[00:25:07] James Dice: Cool. And then what was the results?

[00:25:11] Carmel Pratt: So the result overall is that we found some, really what we call low-hanging fruit designed decisions that helped to significantly drive down, embodied carbon without changing. You know, we, we. Recreate any like big, innovative, whatever thing we were, we were we had to stay within the bounds of of cement CMU, like block and plank superstructure.

So in that sense, we were maybe a little limited in terms of not being able to use bio-based material, like wood and, and other kind of carbon sequestering material in our superstructure. We were able to find, for example a CMU supplier that does carbon capture within their manufacturer process.

So if you're using cement CMU, find the best cement [00:26:00] possible that that lowers inherently in their manufacturing process, that lowers embodied. That the outcome I think was successful in showing that if you spend a little bit of time thinking about these things, you can really see major reductions.

And really the point of the study was to share what we found so that people can make these decisions very easily. Like now you have all the information in front of you, you can kind of. Skip the calculations and the bang, your head across different manufacturers and whatnot, and get straight to these low hanging fruit decisions.

[00:26:34] James Dice: Okay. And I read the study, I'll put the link to the study in the show notes. It sounds like you guys had the significant reduction was something like 20 to 45%. If I remember correctly, is that the sort of reduction you're talking to.

[00:26:48] Carmel Pratt: Yeah. Yeah. And it, that falls in line with with a study that, that came out that was more general.

It wasn't like. Project specific case study, but the carbon leadership forum, the the folks that [00:27:00] have kind of rang the alarms and set out some of the framework and tools for calculating embodied carbon put out a study that showed that with no cost increase you could get, anywhere between 20 to 40% reduction in embodied carbon, just by making better decisions.

[00:27:17] James Dice: Hey guys, just another quick note from our sponsor Nexus labs. And then we'll get back to the show. This episode is brought to you by nexus foundations, our introductory course on the smart buildings industry. If you're new to the industry, this course is for you. If you're an industry vet, but want to understand how technology is changing things.

This course is also for you. The alumni are raving about the content, which they say pulls it all together, and they also love getting to meet the other students on the weekly zoom calls and in the private chat room, you can find out more about the course@courses.nexus lab. Start online. All right, back to the interview

So what were the, some of the low hanging fruit things besides the CMU that you

[00:27:57] Carmel Pratt: meant? Yeah, so concrete was a [00:28:00] huge one. Reducing and, and and simplifying the refrigerant runs. So this, this building is centralized VRF systems with what would typically be a ton of refrigerant lines running around to connect.

Outdoor condensers to the indoor fan coil units. And I, I appreciated the book behind you when, when we when we first got on. But if anyone's read that drawdown book, they know that refrigerant is like the number one drawdown opportunity. Just globally, the, the missions that we put out with tiny leaks of refrigerant have a huge global warming potential.

And so, it's one of those. Areas that if you can just reduce the amount of fittings and the amount of the length of lines of refrigerator in a building, you have, you've cut down a lot of potential carbon emissions through refrigerant leaks. Another way is To just again, reduce or optimize your installation.

So we were able to reduce our roof installation our wall installation. We were able to keep double pane windows instead of going to a triple pane [00:29:00] by just optimizing the U value. So like the thermal resistance value with the solar heat gain value too, to kind of help keep our, our loads, right.

For heating and cooling. Yeah. There's other low-hanging fruit just in like, decisions you make on finishes drywall the, the density and weight of drywall and the material that goes into it. The flooring and paint and whatever other finishes you use. And the, I think the.

Biggest opportunity is sourcing things more locally. So, finding this and the transportation. Yeah.

[00:29:34] James Dice: Yeah. Okay. Cool. So what were the sort of ways that much, and that you've mentioned this a little bit, that people can just take your lessons learned and implement them, but how can, how does the industry need to change in the way that they, we mentioned two of them actually, which is take your lessons learned, but also this new sort of what I think is new, this sort of.

Energy modeling with the [00:30:00] EPD, with the embodied carbon considered in the process. What are the other ways in which the industry needs to sort of change to sort of accommodate this, these insights?

[00:30:12] Carmel Pratt: Yeah, I think one of the general ways is just to, again, like take a step back and pause and Think about doing things differently, and not doing things the way we've been doing them.

Cause cause they work and then that's, that's a great argument. But we know now what we didn't know, even five years ago. So just having these conversations, right, again, as simple as like putting in spec language, That requires a contractor to go out to a couple of different vendors or manufacturers and ask them questions.

Maybe make them, go through the EPD process if they haven't. Right. That's a voluntary process that not all manufacturers do. So we don't maybe have the, the numbers that we need on a product. The [00:31:00] more we talk about this, the more we ask these questions, the more kind of market penetration we're going to get.

And the more we're going to bring down costs for like better alternative options.

[00:31:12] James Dice: Absolutely. Yeah. I could see just the specifier could just put, the person has to have their data published in order to be selected on this project or that those types of things could transform the supply chain pretty

[00:31:26] Carmel Pratt: quickly.

Yeah. And we're seeing that I'll just make a quick plug on the policy side. We are seeing that. New York just recently passed a legislation that requires any like, big capital infrastructure projects to source low carbon concrete. And so like, this is gonna really be that, that shift in that push that suppliers in New York are going to just have to, kind of change with the times.

[00:31:53] James Dice: Got it. So your, your case study also mentioned there's an equity component to this. Can you talk a [00:32:00] little bit more about that?

[00:32:01] Carmel Pratt: Yeah. So, just this, this project being an affordable housing development the, the importance there is cost compression and making the. Decisions that benefit, the planet for sure benefit the tenants and the users of a building, but also make this cost-effective so we can continue to create, new, affordable housing at.

At a, at a lower cost instead of having to to make kind of worse decisions to keep costs down that, have a negative effect on, on carbon. And, and, the. The funding that we got from nicer to help, to kind of offset some of those costs as well to the, to the developer.

Who's, by the way, a nonprofit who also provides like social services and community services to the, to the tenants and to the communities that they that they develop and work in. So, just providing these [00:33:00] things to, to people that. Need it than need to be housed. And then the other component is I think, education and awareness, right?

There's Equity is opening up opportunities for people to learn about and know about these things. And I always say from like a workforce development kind of standpoint it's where we're opening up information, in an open-source way that that gets it in the hands of anyone that's interested.

Very cool.

[00:33:28] James Dice: Very cool. Okay. Let's go to the, over to the operational carbon side. Sounds like you're working on a lot of projects that are designed to reduce operational carbon as well. And not just not just kind of focused on ECC, which has been sort of neglected. Right. I think a big thing right now that I'm sort of there to got out and thinking a lot about not just with my house, but also just as the, that the industry, the commercial building industry as a whole.

Which is electrification. So can you talk about kind of the trends and technologies you're [00:34:00] seeing right now on the electrification side, and maybe start with the laws in New York that are sort of forcing, forcing people's hand here.

[00:34:09] Carmel Pratt: Yeah, yeah. Again um, Policy for good, and in some ways just forcing good good change.

So New York city recently adopted a local all local at 97, which puts a carbon emissions cap on buildings over 25,000 square feet. And, and it, it basically, Requires existing buildings to to do energy retrofits and bring down their, their operational carbon. It's also requiring even new buildings and buildings under design to be thinking about what those caps are going to be.

Those carbon caps are going to be so there's several years where they you know notch down the, the. Caps that they have in 20 24, 20 30, 20 50. So it's, it's causing people to and sorry, I should back up and say that anything over those carbon caps [00:35:00] gets gets a financial penalty, right?

So you're paying for. Any amount of carbon you expend over those caps. So it's putting a price on carbon and it's it's really forcing people's hands in in reducing their, their carbon. And there was another local law recently passed that banned fossil fuel use in new buildings.

So. That's you know, changing the, the, we're just talking about design decisions, changing the landscape and really pushing, pushing for electrified systems. Electrification has come a long way in the past, like really few years. In the last three to five years what was before a very nut, a hard nut to crack on the domestic hot water side there was, previously not a lot of good options out there other than electric resistance you know, hot water heaters.

We now have really great heat pump technology to electrify domestic hot water. And we're seeing that [00:36:00] evolve at a great pace. The, the one, I guess, caution about that, about moving to heat pumps, both on the domestic hot water side and on the heating and cooling side is of course the refrigerant

[00:36:15] James Dice: just talks about that.

[00:36:16] Carmel Pratt: Yeah. Yeah. So, we've, we've. Electrified a ton of systems. We've had refrigerants around for a while, any, split system with cooling uses refrigerant. But the key is what kind of refrigerant are using the typical that we've seen that was better than the, the ozone depleting refrigerants of the past is still much worse, in terms of global warming potential compared to.

Actual CO2, which, which, is a one-to-one equivalent. In terms of emissions, whereas our four, 10 a is like 2000 plus ratio of, of of carbon emissions. So all that is to say that we are [00:37:00] seeing innovation on. On that side, especially with domestic hot water of using CO2 as a refrigerant instead of some of these more harmful refrigerants.

And so, that's a huge development where we can now design large central domestic hot water systems that use CO2 refrigerant and and fully electrify with the benefits of, of heat pump technology, inverter driven heat pump. Got

[00:37:27] James Dice: it. Is it going more towards, cause like I'm looking at a heat pump, water heater from my house and it obviously rejects cold air out into the ambient space that's sitting in.

Are there like heat recovery? Options here that are connecting different loads in the building together versus them being siloed in the past, or how's that work today?

[00:37:48] Carmel Pratt: Yeah, that, that's an interesting question. I mean, so there are different technologies out there. Some of them have those condensers on the exterior, so you're not drawing down your, your ambient, [00:38:00] ambient heat.

And some of them are packaged. So you'll have that. Inside. And then yeah, you have to worry about how, how much it lowers the, the temperature indoors. For the most part, the the exterior application where you have the condenser on the outside is preferable because of that, because it doesn't throw off your heating, cooling loads, but you can take advantage of that in a building where you have.

Very varied kind of load profiles and like program and use in a building. For example, if you have a data center. Yeah. The

[00:38:34] James Dice: constant cooling load

[00:38:36] Carmel Pratt: year-round right. Just anywhere where you have high, intense. He gains from equipment or people or whatever it might be. You can use that to your advantage.

I recall one project and apologies. I can't remember the name of it, but it was in in Albany. I believe that put in the outdoor condensers, have a heat pump, water heater into a commercial kitchen [00:39:00] space and was using the reject heat from that. To heat. It's hot water in a much more efficient way.

In, in a, in a residential building that happened have a, a commercial kitchen on the first floor. So, yeah.

[00:39:14] James Dice: Cool. So what do you think? So when I think about electrification, I don't think like new buildings are that hard. Maybe they are, but it doesn't feel like they're that they're like the big challenge.

What do you think the big challenges are and the ones that we need to get around with respect to electrifying existing books?

[00:39:33] Carmel Pratt: Yeah, you're right. It is, we've, we figured that out. There's like, and, and that, that fossil fuel ban in New York kind of points to it. Like there's no reason we should be putting in new gas lines and designing, gas into new buildings, but on the existing billing side, it's harder because really the, the biggest hurdle is the existing electrical infrastru.

And having to upgrade for the loads that would carry, heating, cooling, hot water, and, and [00:40:00] anything else you're potentially electrifying from oil or gas system. And then, so that's, that's one side, just the electrical load of the building and that infrastructure, and then whatever existing infrastructure you have, whether it's hydronic distribution, or steam distribution, you have to.

Retrofit that to, a new, whatever it might be. He pumps are a little more straightforward and, you can you can kind of just ignore the existing distribution you have. But ideally. From a cost perspective. You want to look at how you can reuse the existing distribution system. And that becomes harder to find equipment that's plug and play, with whatever existing distribution you have, just, you can't just throw in electric heat pump.

And so that, that becomes difficult. So, yeah, I'd say electrical infrastructure and distribution are the big hurdles,

[00:40:52] James Dice: the challenges I see. And I'd love to get your take on this. I'm viewing this kind of through the lens of my own residential water [00:41:00] heater, right? So the big challenge I see beyond, I mean, those that you just mentioned are huge.

Like for instance, I have to do $2,000 electrical upgrades just to do a heat pump just to start, But set that aside. I feel like there's challenges in that now, instead of calling a plumber, I'm now the GC, right? I now have electrical sub a plumbing sub and potentially an HVAC sub if I don't, if I need to get, the projected air.

Somewhere else. Right? So that I'm now like this project developer, I think that's a big challenge. Because you're now involving all these different trades that you weren't before. The other challenge is similar in that I can't find anyone in the local supply chain that has done what I'm asking them to do before.

Right. So there's almost like. And then once I found people that are willing to do it, even though they haven't done it before, they're giving me a price premium because they're unsure. Right. And I'm sitting here going, I know what, I know what this is. I know what the scope is. There's no reason that your labor [00:42:00] cost is doubled.

Than what it was before with the gas. It's just because you're more comfortable with doing what you've always done. And so now I'm having that conversations, right. Which I guess is the role of the GC, right. Because I am the GC, but I feel like it's a big challenge for people. You can talk about homeowners, but let's take this to the commercial industry.

Right? How, how are we going to get around those sort of supply chain challenges at scale in every city? Right. That makes me feel very overwhelmed. What do you think.

[00:42:30] Carmel Pratt: Yeah, it overwhelms me too. And it overwhelmed developers who, so you hit the nail on the head and that's exactly where I was going to take this.

Like you take. Home homeowners scenario and you scale that out to massive buildings and it becomes even more complicated and costly, right? Talk about a cost premium for the risk of the unknown. The the challenges and, and some of the things that, that. Asking nicer to, to, to fund for example, is workforce development and training [00:43:00] contractors in this work so that they can feel more comfortable bringing their costs down.

The other part of that is the ongoing maintenance and operation, right? There's a risk that you take on with this new equipment and not knowing what, what the true lifespan is. And who's going to service that. And at what cost for, the ongoing for, for, for its useful life. And that's a big cost hurdle that, people are not yet, we haven't gotten over yet.

And that's, that's workforce development, it's, it's education, it's knowledge. The other side is the cost of electricity. Hasn't come down, in certain places that makes it make sense yet. So I talked earlier about cleaning up our grid, but like cleaning it up and, making electricity.

Cost-effective whether that's like. Starting to do kind of like rate subsidies to begin with, to get people interested and, and, help them bring down the first cost by knowing that they can lock in at a good electrical rate down the line where there's, you don't know what's going to happen [00:44:00] 20 years from now in terms of what you pay for electricity.

So, that's, that's equally as important and as much of a hurdle on the cost of.

[00:44:10] James Dice: Can I ask you a moral question right now on the air, put you on the spot with my personal problems. So if I look at my project in particular, it's like a perfect microcosm for all of this and I'm planning to write about it, but it doesn't help me figure out exactly what to do.

Right. So. Well, you just said, we have a really high electric rate replay at 14 cents a kilowatt hour, and we have a really low gas rate. It's like a dollar, a therm or something. Ridiculous. And so what that means for me right now is that it's actually, there's no safe. Going from gas to electric heat pump water heater, even though the heat pump is three, whatever times more efficient making hot water.

There's absolutely no savings for me right now. So, and the cost is a cost is three X. So the cost is three [00:45:00] times given the electrical upgrades, given the contractor, premium. And given the fact that the heat pump costs more than the old style water heater. So three, three times. So I'm spending about essentially about 4,000 extra dollars for no savings today, right?

What would you do? What were what's the right thing to do? I guess?

[00:45:24] Carmel Pratt: Yeah. I mean, the right thing to do is to idealize this future state, where we have, or maybe you add solar or some other renewable energy to your house, and you're able to kind of bring down your electrical costs and morally, that.

Cut the line with fossil fuels, but you're speaking to, a passionate sustainability nerd who thinks about those things. And I will say, listen, I, I feel you. I live in a house that was built in 1900 and I've had to make these decisions in real time. And, sometimes your backs against the wall and you don't have that extra $4,000 and you have to [00:46:00] make a decision that just.

Gets you, eating in the winter, what he needed. So to that I say, and, and this kind of maybe answers your previous question about existing buildings. Like maybe you can't do it all, like maybe you're not ready to switch to, heat pump, water heater, but like start with upgrading your electrical service and, and, and then when you have the money, like work onto the next thing, same thing on the existing building side.

Start with electrifying one thing or updating, your, your your electrical loads for the future capacity that you know, you're going to want to get into down the line, even if you don't have the money to do it now.

[00:46:39] James Dice: Yeah. I love it. I love it. Cool. That was a great conversation. I'd love to end with some carve-outs.

So what TV show, book, podcasts, movie would you recommend to the audience? I'll go first. So one of the ones that I'm reading right now, and I'm not that far into it, but it's called after cooling and it really relates to it's a [00:47:00] book, a book called after cooling and it's, it's written by a journalist. So it's.

It's really fun and the way that he explains all the things that people like us live, eat and breathe every day, but he's explaining refrigerants to a layman audience. And, but then he's like, he's like going to the source. So he's going to people that are, selling refrigerants on the black market, like our 12.

He's going to those people and he's like participating in those transactions. And like, it's a really fun read from that perspective because he's, he's getting down into the ground of this issue. But that's about where I'm at. I'm like 20% to the book, but it's a really good book in that. It talks about all the challenges you were talking about earlier from our refrigerant and mission standpoint and the leaking huge, huge, huge

[00:47:43] Carmel Pratt: deal.

Yeah. Very cool. I haven't heard of that. I have to check it out. Yeah. Related to embodied carbon, I would recommend a new carbon architecture by Bruce King and others. It's a great overview. It was that that's a book. Yeah. Yeah. That's a book. [00:48:00] That gives a great overview and breaks down in great detail.

Like every building component and how you could draw down carbon. Cool. And then the book I'm currently reading that I'm, I'm, I've hardly gotten through the first couple of chapters but it's called healthy buildings. And just in general, I don't know if you've heard of my house is killing me those types of books that that deal with indoor air quality are equal parts, scary and informative.

[00:48:26] James Dice: Yeah, absolutely. Yeah. The healthy buildings book is a one that's come up before, definitely on podcasts and in the community. Definitely recommend it for sure.

[00:48:36] Carmel Pratt: Yeah. Speaking of podcasts, I will plug the passive house accelerator podcast. The passive house podcast, I believe is what you can look it up on, on the streaming services, but they, are deep into this world and.

And put out some great content.

[00:48:54] James Dice: All right. Carmel, I appreciate you coming on the show and teaching us all about all these things that we don't normally talk [00:49:00] about.

[00:49:01] Carmel Pratt: Yeah. Thanks for having me. This is great conversation

[00:49:07] James Dice: All right friends, thanks for listening to this episode of the Nexus Podcast. For more episodes like this and to get the weekly Nexus Newsletter, which by the way, readers have said is the best way to stay up to date on the future of the smart building industry, please subscribe at nexuslabs.online. You can find the show notes for this conversation there as well. Have a great day.