Drone Data Helps a Minnesota City Conserve Energy — Episode 141 of Local Energy Rules

Date: 20 Oct 2021 | posted in: Energy, Energy Self Reliant States | 0 Facebooktwitterredditmail

Maintaining healthy, comfortable buildings can be expensive in Minnesota — especially during polar vortex events. Warren, a small city in Northern Minnesota, is offering an innovative public service: images that reveal building heat loss, captured by drones.

For this episode of the Local Energy Rules Podcast, host John Farrell speaks with City Administrator Shannon Mortenson of Warren, Minnesota. Mortenson and the city partnered with a community college to pilot a novel project; the college, using drones and thermal cameras, captured images that display energy leaks in homes and businesses. Farrell and Mortenson discuss the first-of-its-kind thermal imaging project, lessons learned from the pilot, and how cities can help residents conserve energy.

Listen to the full episode and explore more resources below — including a transcript and summary of the conversation.

Shannon Mortenson: I think it’s just good to have a handle on where’s your energy loss in the community and how can we be more efficient? How can we be good stewards and try to mitigate climate change and increase sustainability in our community?
John Farrell: How can you tell if your utility customers are wasting energy without stepping inside their building? The city owned electric and gas utilities in the small town of Warren, Minnesota, decided to find out, creating a partnership with a local community college to do thermal imaging on every building in the community with drones. City Administrator Shannon Mortenson joined me in September, 2021 to talk about the novel method for identifying energy loss and how the city’s utilities will use it along with unique financing to help residents cut their energy bills and carbon emissions. I’m John Farrell, Director of the Energy Democracy Initiative at the Institute for Local Self-Reliance and this is Local Energy Rules, a biweekly podcast sharing powerful stories about local, renewable energy. Welcome to Local Energy Rules, Shannon.
Shannon Mortenson: Thank you, John. I appreciate this opportunity. I’m looking forward to our conversation.
John Farrell: Yeah, me too. Very much. I think one of the things that’s probably important to start out with is that people listening to this program, probably a lot of them live in bigger cities and might have no idea what a city administrator does because they might be used to a council and a mayor and then the offices that serve those different agencies served as arms of government. Could you just explain a little bit, like, what does the city administrator do in a, in a relatively small town?
Shannon Mortenson: Yes. The city administrator role in a smaller community is you oversee everything in the community. Everything that the city operates. In our case in Warren, we own all the utilities. We have a very active EDA. We have a nursing home and assisted living. So it’s my, my role as administrator to oversee all of the functions of the local city government, um, and the staff that help operate the city.
John Farrell: So do you have, is there a mayor or a council that you’re also working with out of curiosity?
Shannon Mortenson: Yes. We have a mayor and six elected officials cause we’re a home rule charter city. So we do have our own charter that we go by. And then our EDA is also a board of seven and then we have our nursing home board that also is a board of seven.
John Farrell: Sure. Okay. So lots of different boards that help to run the thing, but you kind of make sure all of it is working together as the city administrator.
Shannon Mortenson: Yes. I give them all of the information they need to provide an informed decision.
John Farrell: So I was hoping you could talk a little bit about Warren’s energy system, as you mentioned, in terms of the different services that the city provides. You have your own energy utilities. So could you explain, like how, how does that work? Who’s providing those utility services? How do folks heat their homes in Warren, Minnesota?
Shannon Mortenson: Yes. The city owns all of the utilities. So that means we own the electrical utility. So we have the staff that operates that. We own the natural gas utility. So we have the staff that operates that. Water, sewer, and sanitation. With our electric, we don’t generate, we do purchase. So we belong to Northern Municipal Power Agency. That is a consortium of cities that we buy energy together. Most of our energy does come from Minnkota. For natural gas, the same thing. There is a consortium of cities that purchase together and we purchased from Constellation Energy. So we have complete control over our distribution within the city for the electric and the gas, along with the water, sewer, and sanitation, but I’ll concentrate on the electric and the gas today because that is how people heat their homes. And one, a large percentage do heat their homes now with natural gas. And we’ve seen that change happen in the last six or seven years when the price of natural gas actually stabilized, it became cheaper and it’s very stable pricing. So we’ve seen a lot of homes transition to natural gas, but there is still some that have all electric.
John Farrell: I’m sure that home heating bills are fairly big deal in Warren, as with much of the upper Midwest. I had heard about, and the reason I was interested in talking to you Shannon is I heard about a pretty interesting way that Warren utilities were trying to help home and business owners learn about their building’s energy use. Could you tell us about that project?
Shannon Mortenson: Yes. The project that we have been working on for the last four years, I will say to start out with it was a pilot project. So this had not been done anywhere else, which is why it’s taken longer. But we had started in 2017 working with Northland Community College, which we’re 30 minutes from Thief River Falls. And that’s where the college is located and they have a drone program. So we started working with them to do a pilot project in which they do thermal imaging of every structure in our community using drones. So they can fly over. They don’t have to worry, they don’t fly down the streets. So they’re not getting into people’s windows or anything, but with their technology that they use at the school, and then they are using it as a teaching mechanism, also, it has been a nice collaboration and partnership and they have completed all of the thermal imaging in the entire community using drones.
John Farrell: So can you tell me a little bit more about that? So I’m picturing a drone, so I’ve seen people fly them around. It can be up a few hundred feet. They’re going over the different buildings. They’ve got some sort of thermal camera, right? So that’s, they’re taking pictures as they go over. Were there any challenges in terms of when do you do yeah. When, like, when do you do this? Can you do it on like a normal spring day? Like, is it, do you have to do it in the winter and the summer? How, how is, how are you able to get the pictures that give people information about how their home operates?
Shannon Mortenson: John, that is a great question because with it being a pilot project and there was a huge learning curve and there was a few things that we knew from the get-go was it probably should be done when people have their furnaces on, because you can capture heat loss, greater with people’s furnaces on than with their air conditioning units and that everyone has air conditioning or has it on, but you know, that their furnace is on and they started doing the thermal scans in November. Then they quickly realized that you had to do them when the temperature was above 32 degrees, or you had a huge quick drain on the batteries for the drones. So that was, that was one challenge that was interesting. Wind, it had to be an extremely still evening.

And they started first doing them right after sunset. And then they realized that there was still a lot of residual heat. So all of a sudden we had every roof in Warren had heat lost, but it was actually the residual heat from the day. So then they decided to do the scans right before sunrise. And so they came to Warren about 5:30 or so in the morning. And then, um, it doesn’t take long for a roof to heat up when the sun rises. So they didn’t, they were thinking that you would not have as much heat absorbed in the morning, but that didn’t work. So then they ended up doing all the scans at about two in the morning on a still morning that it was above 32 degrees, which only leaves us about, and the furnaces have to be on, which left a lot of the scans happening in November for a short period of time. They did some in December, January, February, depending on the, you know, if it happened to be a little bit of a warm period, then they would start them up again in March. But then if it was a warm spring, you had a very short window. So that’s a lot of reason of why it took so long to get all the scans completed, where all those learning curves with when you can do them. So now they’re up in the middle of the night for about four hours when nobody else is up and moving.

John Farrell: Probably also helps too, in terms of people noticing the drones going over that at that time, most people that are asleep.
Shannon Mortenson: And they’re very quiet. And they do fly at a little over 200 feet. So they were not very noticeable in the community when they were flying them. We did let people know, we did contact them because they knew which — they would do quadrants of the city. So they knew which blocks they were going to do each time. So we would contact those residents so they knew if they saw something out of the ordinary, it was probably a drone.
John Farrell: Just out of curiosity. I was, I liked doing some kind of background research on the communities that I, when I’m talking to folks about the energy work that they’re doing. And I was just curious, did the use of drones for this energy project spark any references to the UFO incident that would involve the Marshall county sheriff back in 1979, or was the information you got more practical?
Shannon Mortenson: You know, I wish I had a good story to tell you with that, but the information was more practical, no one put together that it could be a UFO. And because yes, we do have the UFO sighting from 1979 and the car is at our local museum, but no, we did not have any calls with another UFO sighting, unfortunately.
John Farrell: I feel like I would love to ask you more questions about the UFO thing. Cause in my Googling, it sounds like there’s some contention about among the UFO community about whether or not it was a legitimate sighting or not, but I’ll spare us getting into that and ask you a little bit more about the actual data that you collected. Which is to know, you know, how is the city using the data? So you’ve got you, these are still images, right? They’re not videos of the different homes. If folks have seen thermal images before there’s, you know, blue is cold and red is hot, at least on the ones that I’ve seen, how are the city and the utility is using those images?
Shannon Mortenson: Our plan is because they’re still extrapolating the data. And actually right now they’re stitching, they have to stitch together all the quadrants. And then they’re also going to overlay that with our GIS map so that you will have like an actual photo of the structure that was taken by the drones and then the thermal imaging. But our plan is to take that data and allow residents to come in, sit down with staff and see where their greatest energy loss is in their homes. You know, it could be windows, doors, roof, that way they can make a decision that would give them the greatest energy savings and cost savings at that point in their homes. And we are hoping also we have, we participated in an inclusive financing study because we own our own utilities. We would like to provide a program that allows residents to get a loan from the city and they payback through the savings, anticipated savings on their utility bill.
John Farrell: Can you tell me a little bit more? I obviously, I was part of that study, so I’m not asking for myself, but for our listeners, could you explain a little bit more about the inclusive financing idea? So it sounds like you would get some money from the utility to pay for things improvements you might make to make your home more energy efficient, but then you earn it back on your utility bill? Does that sound right?
Shannon Mortenson: Right. Yes, but we’ll use roof, let’s do insulation on a roof because that has the quickest payback. So if the roof insulation costs $2,500, the resident would apply for that from the city. And we would determine prior that you might have $50 a month savings. So their utility bill would have that $50 a month on the bill as a loan payment, but they would also have, they would also see the savings from having the roof insulation. So their bill should not change. But then after the specified amount of time, which would probably be about two to three years, then they would, after the loan is paid back, then of course they would still see that savings on their bill, but there would be a way for them to finance the project and get those savings. And the project would be with the structure, not the resident. And so if they were to move that loan would just stay with that property.
John Farrell: Got it. So the nice thing of be, if I do this improvement, and maybe I move in a year, the next person who moves in they get to enjoy the benefits of the installation, and then they can finish paying it off. But the utility bill is lower because you’ve made an improvement. So it’s not like this is a burden for them moving into that house. In fact, it should be better off than it was before.
Shannon Mortenson: Correct.
John Farrell: So I meant to jump back when you were talking about sort of the work that’s being done with the thermal images and the GIS map, et cetera, are the students from the community college doing that work still with the city? Is it, or is it now in the hands of the city utility and that’s where the work is being done?
Shannon Mortenson: Oh, the work is still being done at the college. They are using that as a training ground for their students. And part of it too, with the timing taking so long, the pandemic obviously changed a lot of, um, attendance in college. So that did, of course pushed the project back when they weren’t in person. But we know that the data’s there and we’ll have a really good program when everything’s complete.
John Farrell: Yeah, that’s great. Do you imagine that other small communities, other utilities might be able to duplicate this product without the help of a local community college? It seems like that’s been such an asset to this project to have the fact that they have a drone program. So they have the drones that the students have time and expertise with the drones themselves. And presumably also folks can, you know, I’ve seen a lot of students who have a lot of talent with GIS, for example, has that been essential to the making this project happen?
Shannon Mortenson: You know, it has been essential. And in visiting with the professor, you know, the hope would be that some of those students decide to start a company that they market themselves to municipalities and have these thermal scans done. Everyone’s looking to see how can I save money in my own home. And cities are trying to find, figure out, like, how can we help our residents? How can they save energy? Our energy costs keep increasing and just, how can we be good stewards of our energy usage? So hopefully someone would, if you can’t engage in a partnership with a local college, like we were fortunate to have that there’s companies out there that do that work.
John Farrell: Do you have any sense, thinking of that idea of the students taking this and making a business out of it, do you have any sense of how much it costs like for each building or each block or something like that to get the pictures? I’m sure the students weren’t necessarily like sending you invoices or billing time, right. They’re doing this as part of a collaborative project, but I’m just curious, cause I’m sure that other cities that are interested in this would probably want to know, okay, well, what might we have to spend to map out the different properties around our city?
Shannon Mortenson: I do not know how much it would cost. We have been fortunate to not see any invoices. I know the college wrote a grant to make sure that their portions were covered. And I know the drone itself was a $40,000 drone, but I don’t know how much anything costs after that.
John Farrell: That is a much more sophisticated drone than the one my son flies around. And I’m glad that I don’t give him the controls to one that cost that much. That’s for sure.

We’re going to take a short break. When we come back, we learn about other cities that have called Shannon to learn about the drone program, what the Warren utility see as the collective advantage of doing the thermal scans, and we talk about a privacy barrier to using the scans as widely as the city might like. You’re listening to a Local Energy Rules interview with Shannon Mortenson, city administrator of Warren, a small town with public utilities in Northwestern Minnesota.

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John Farrell: I was curious, I know that your project has been covered by other folks like the clean energy resource teams and other folks who have shared stories about this collaboration. Have you had other cities come calling you about the effort and what do you tell them about it?
Shannon Mortenson: I have had other cities call. I’ve had cities call from Texas, from Illinois, from Iowa. I had a company actually call me from Canada. They do that work up in Canada and they were just curious how we were approaching our processes to see if they could improve on theirs and what we were learning. And I just, I, I tell them that, I mean, we did have this partnership. So to see if there’s any colleges in their area that have a drone program or some type of training ground, you know, or engage in a business that may have it because it’s going to be very beneficial to just have that data. Even if you just did your municipal buildings, you’re still saving the taxpayers dollars on what your operating costs are as a city. It was very interesting more so when I got the call from the Canadian company, they had done like the major metropolitan areas in Canada. And were curious how you do a smaller community and what the benefits of it would be.
John Farrell: When you talk about like the municipal buildings, for example, or even this Canadian company that was doing it for a lot of other properties, do you feel like it is, I guess what made this so interesting to pursue, right? There are other ways to do energy audits. People can come to your house and they poke through and look at the installation. They, they can do thermal imaging from inside your home. What do you think makes this worth considering as a tool? What is helpful about the fact that it can be done? Uh, I guess you can do it in some ways, without even really asking the resident of the building, right? You can get that information without having to go in and schedule a time to meet with the person. What are the other benefits that you think of to doing this kind of thermal imaging, as opposed to other approaches, to try to inform people about the energy use of their property?
Shannon Mortenson: On the city side, we can determine what our energy loss is overall in the community and where that energy loss is occurring. Because we’re still buying our electricity and our natural gas from a supplier, so if you have a lot of energy usage, a lot of electric, let’s say, okay, you have a lot of electrical usage happening when people are in their homes from four to eight in the winter, that also might be a red zone for the utility company that’s selling us the power. So we’re buying expensive power. So if we can, we, if we can cut our red zone usage, we’re going to have cheaper electricity bills for the city, what we purchase wholesale. And I think it’s just good to have a handle on where’s your energy loss in the community and how can we be more efficient? How can we be good stewards and try to mitigate climate change and increase sustainability in our community? This whole project came about because we’re a member of the Climate Smart Municipalities Partnership. And we have a partner city that we work with in Germany, Arnsberg Germany. They also did the thermal scans. So we compared that data on how their building practices versus our building practices, but we’re also, we’re working together transatlantic on climate protection measures and this plays in nicely to how can we curb energy use?.
John Farrell: Okay. And I’m thinking about a city like Minneapolis, which also participated in the study of inclusive financing that we talked about earlier. I work on a citizen advisory committee to the city around energy, and I’ve pitched this idea of thermal imaging. It’s never quite risen to the top of the different things that they want to consider. And I wonder if you think, if you have any thoughts about whether it would work as well in Minneapolis’s circumstance where the city doesn’t own the utilities, right? We have a for-profit electric company, a for-profit gas company. They maybe they don’t have quite the same incentives to reduce energy use. Like you mentioned, I thought that was a great story about the Warren utility, right? You, you know, if you can reduce the number of customers that are using electricity or the amount of energy that they’re using on an, in the afternoon, and that it’s expensive power where you can lower the overall bills for all customers. And that’s something that you’re thinking about as a public utility. Do you think this works as well in a, you know, or do you think there are still ways that a city can use it, even if they don’t control the utility companies?
Shannon Mortenson: I think there is. I think that cities could use the information to just be good partners with their residents. We did these thermal scans. Here’s, here’s some areas you could potentially save money in your building. Like a lot of apartment buildings. Where’s that energy loss. Even if the owner isn’t paying the utility bill, you still want to make sure that as the owner, I mean, he or she still wants to make sure that, okay, how can I, how can I make this affordable for my residents? If they’re paying less on their energy bill, then they won’t be so strapped to pay their rent possibly. Or any of, I mean, there’s a lot of beautiful old homes in Minneapolis. Where are those heat losses? You know, do you need some new windows? Do you need some roof installation? You just would be a good partner with your residents. Even if you pull the utility out of it.
John Farrell: I liked that you mentioned the old homes in Minneapolis. I think I saw some really remarkable statistic that something like one in four Minneapolis homes doesn’t even have wall insulation because of the time in which they were built. And the fact that that was not typical at the time. And I just can’t imagine what it would be like living in a house without wall insulation. So it is a really striking, I imagine that shows up pretty good on a thermal image for one, but also that it would be something that could save people a lot of money and make their home a lot more comfortable as well. So definitely a win-win opportunity there.
Shannon Mortenson: And sometimes you just don’t know what you don’t know if you haven’t thought about your energy usage, because it’s always been the same. That doesn’t mean it’s efficient just because your usage has been the same, right?
John Farrell: Yeah, absolutely. You know, speaking of that idea of the thermal imaging picking up, for example, those homes in Minneapolis. Is the utility in Warren likely to communicate with customers? So let’s say you’ve got pictures and you have certain customers who’s showing really significant heat loss on the thermal image. Is the utility going to sort of proactively reach out to those customers and say, Hey, you know, we have this picture that we took, you might’ve heard about us doing this program. It looks like you could really benefit from some energy efficiency improvements, some installation, et cetera. Are there plans to use the images in that particular way in terms of doing outreach?
Shannon Mortenson: It comes to the privacy laws. We actually cannot do that. They have to come in and request the data. As much as we would love to, because I’m sure that there is homes and businesses, even, that we would love to reach out to, because we do have like a funding mechanism for commercial businesses right now, also that provides low interest loans. Yeah. We, because of privacy laws, we can’t use the data in that regard.
John Farrell: Is that sort of surprising and I’m sure a little bit disappointing, is that because the city is a public entity or is that a rule for, uh, you to any utility company that would take these kinds of images? What, what is, what prevents you from sharing them?
Shannon Mortenson: It came from the college as part of their drone imaging was that we, as a utility, could not use the data to go out and help customers. They had to come to us because it isn’t classified as public data. There probably is more, I don’t, I don’t know where the ruling and stuff came from. That was just in our conversations with the college. And he was like, the professor was like, no, you can’t, you can’t go through this and say, okay, you need to do this and this, they have to come to you.
John Farrell: Fascinating. I wonder if there’s a different way to structure that. And you know, I don’t know if it has to do with the partnership. Maybe the college’s lawyer looked at that and said, Ooh, we don’t want that liability or something. It’s just sort of sad because I know one of the things I’ve thought about in Minneapolis would be how effective it could be to send someone a postcard that’s a thermal image of their house. And to say, look at the heat loss you have here, call us up to get more information about this imaging program that we did as the city and how we can help lower your energy bill.
Shannon Mortenson: Yeah, it’s interesting cause that was one of our main things when we had first started this was, okay, good. Now we can, we can go to the resident because then we’re going to be good stewards and say, okay, Hey, this is where you’re losing your energy. Like we talked about, you don’t know what you don’t know, but that was, that was not encouraged. We can, we can have people like if they were to call in and say, why is my utility bill so high? You know, we could say, well, why don’t you come in and look at your thermal scans and see what we can do. But yeah, we, it can’t be done where we go after them.
John Farrell: That’s just fascinating. I want to keep asking you questions about that, but I imagine there’s not necessarily more to answer right there and neither you nor I are lawyers. So I’ll spare our listeners.
Shannon Mortenson: I could get you the information, but will not help the listeners of the podcast today.
John Farrell: Yeah, well, I’ll follow up with you Shannon. I would be interested in hearing more about those privacy concerns because obviously there’s a whole world out there of pictures being taken of us, whether it’s like the pictures of streets by Google or Apple or those mapping companies, and now they’re mapping the insides of buildings and things. So I totally understand this is part of that bigger conversation about privacy, but I’m interested to know if it would be, if it’s defined by the particular relationship you had with the college, or if there are other barriers from regulations of utilities or, or just privacy laws in general. So it’d be interesting to follow up. Yeah.

So I wanted to just wrap up and ask you if you had to say what you think the top three things a city utility could do to help its customers have a more comfortable and energy efficient home. Do you think doing a drone fly over getting those thermal images would be on the list? And if not, what do you think the top three things are that a city utility can do to help its customers?

Shannon Mortenson: Well, I think that thermal imaging at least would give you a baseline as a utility on where your energy loss is, and obviously gives you a lot of data to work with. But if that’s not at all feasible, I think if your utility has a thermal imaging camera now, like we do have one here where it just connects to a cell phone and then we can go out and just do quick scans. You know, if they’re wondering, oh, is my door really losing heat? You know, we can do a quick scan of that door and say, oh yep. It looks like you could use some caulking. There is energy audits that can be performed, that they put a blower in your house and see where the heat loss and everything is. And even just, I keep referring to roof installation that is such an easy fix and a lot of energy gets lost through there. And sometimes that’s just as simple as having somebody in utility go up in the attic for that person and say, oh yes, you need another six inches of blow in installation. Those are the things I can think of right off hand that would be beneficial for a utility to help their residents for energy loss. If you can’t do the thermal scans with drones.
John Farrell: Shannon, before we go, any last thoughts or advice that you would offer to other cities or utilities that are thinking about the thermal imaging?
Shannon Mortenson: I would highly recommend it. It’s just, it’s really good data for your residents to be able to pinpoint where their energy loss is. And they will directly benefit at the end with energy savings. Their utility bills won’t be so high. Everybody’s counting their pennies. I just highly recommend any type of scans you could do to help your residents. Everyone will be happy in the end.
John Farrell: Yeah. Thanks so much for taking the time to talk with me. It’s been a pleasure to have you on the podcast.
Shannon Mortenson: Well, John, thank you very much. I appreciate the opportunity and you have a great day.
John Farrell: Thank you so much for listening to this episode of Local Energy Rules with Shannon Mortenson, city administrator of Warren, a small town with public utilities in Northwestern Minnesota, where we discuss their drone powered thermal imaging project. On the show page, look for links to local news coverage, an Energy News Network story, and an overview of a tour run by the University of Minnesota’s Clean Energy Resource Teams. Local Energy Rules is produced by myself and Maria McCoy with editing provided by audio engineer Drew Birschbach. Tune back into Local Energy Rules every two weeks to hear a more powerful stories of communities taking on concentrated power to transform the energy system. Until next time, keep your energy local and thanks for listening.


Warren Sets its Sights on Cutting Edge Tech

Warren owns its utilities, including electric and gas, so Mortenson’s role as city administrator includes oversight of the city’s energy supply. Warren does not generate its own electricity.  Instead, the city is part of a conglomerate of small towns that collectively purchase their electricity from Minnkota Electric Cooperative (and their gas from Constellation Energy).

Warren is also part of the Climate Smart Municipalities Partnership, where cities in Minnesota and Germany collaborate on sustainability and climate issues. Warren is partnered with Arnsberg, Germany. Warren and Arnsberg made a plan to take thermal scans of their communities in order to visualize building inefficiencies and heat loss.

Everyone’s looking to see, ‘how can I save money in my own home?’ And cities are trying to figure out, ‘how can we help our residents? How can they save energy? Our energy costs keep increasing, how can we be good stewards of our energy usage?’

Community, College Partnership

Northland Community College, in nearby Thief River Falls, has a drone program for students and was a natural partner for Warren. Starting in 2017, students at Northland would take thermal images of every building in Warren using drones.

After the drones take the photos, the students stitch them together and correlate them with a map of Warren. They are currently putting the images together, says Mortenson. The maps will soon be available to Warren residents.

Our plan is to take that data and allow residents to come in, sit down with staff and see where their greatest energy loss is in their homes… that way they can make a decision that would give them the greatest energy savings and cost savings

Data Collection Through Trial and Error

Drones fly 200 feet over the city and, using a thermal camera, document how much energy is leaking from buildings. The imaging should be done when furnaces are on, but the air temperature must be at least 32 degrees to sustain the drone’s battery. The air must also be still. Altogether, these conditions leave a small window of opportunity for the imaging in late fall.

In their first attempts at imaging, the students also realized that the photos must be taken in the middle of the night. When the photos were taken shortly after dusk, the residual heat on the roofs read as heat loss across the map. Taken early in the morning, the sun would soon heat the roofs. Residents were notified that drones were flying, so there would be no confusion about the flying objects.


The “Val Johnson Incident,” a notorious UFO sighting, took place in Warren in 1979.


Mortenson believes that Warren’s partnership with the college has been essential. She and the supervising professor hope that the students will start a company and offer the thermal imaging service to other municipalities. The COVID-19 pandemic has slowed progress, says Mortenson, since enrollment at Northland Community College is down and students have been away from the classroom.


Read our summary post about more communities that, using drones with thermal cameras, have democratized access to information about building heat loss.


On-Bill Financing for Energy Efficiency Upgrades

Thermal scans help homeowners identify how their buildings are losing heat. With that information in mind, they can further insulate their home through air sealing, weather stripping, or attic insulation. They may choose to replace their doors or windows altogether.

Energy efficiency upgrades pay off over time, since they reduce energy bills, but many cannot afford the upfront costs of an upgrade. On-bill financing, sometimes called Pay As You Save, ensures that everyone can make their home efficient and comfortable.

In 2019, Warren took part in an inclusive financing feasibility study. Through the program, the building owner takes a loan from the city to make efficiency improvements. They pay the loan back through the savings on their utility bills — and the loan stays with the property, not the resident. Once the loan is paid off, the resident pockets the energy bill savings.

Their bill should not change. But then after the specified amount of time, which would probably be about two to three years, after the loan is paid back, then of course they would still see that savings on their bill.

Because of privacy concerns, the city of Warren cannot use the thermal images to target individuals who may benefit from efficiency upgrades. Homeowners and business owners must approach the city and request their data.

Following in Warren’s Footsteps

Mortenson says that city officials in Texas, Illinois, and Iowa have all approached her out of interest in Warren’s pilot project. The advice she gives is to find a partner like Northland Community College. The college already had the drones (each with a price tag of $40,000) and used the project as a student learning opportunity.

Warren was also an ideal community to pilot thermal imaging because it owns its utilities. The not-for-profit municipal utility had no incentive to fight the project, since energy efficiency only helps city residents. For cities that do not own their utilities, Mortenson believes that thermal imaging is still a worthwhile investment. The data informs residents about their energy use, which they can use to save energy, money, and better afford their other bills.

I think it’s just good to have a handle on where’s your energy loss in the community and how can we be more efficient? How can we be good stewards and try to mitigate climate change and increase sustainability in our community?

Episode Notes

See these resources for more behind the story:

For concrete examples of how towns and cities can take action toward gaining more control over their clean energy future, explore ILSR’s Community Power Toolkit.

Explore local and state policies and programs that help advance clean energy goals across the country, using ILSR’s interactive Community Power Map.


This is the 141st episode of Local Energy Rules, an ILSR podcast with Energy Democracy Director John Farrell, which shares powerful stories of successful local renewable energy and exposes the policy and practical barriers to its expansion.

Local Energy Rules is Produced by ILSR’s John Farrell and Maria McCoy. Audio engineering by Drew Birschbach.

This article originally posted at ilsr.org. For timely updates, follow John Farrell on Twitter, our energy work on Facebook, or sign up to get the Energy Democracy weekly update

Featured Photo Credit: Lars_Nissen from Pixabay

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Maria McCoy

Maria McCoy is a research associate with the Energy Democracy Initiative. In this role, she contributes to blog posts, podcasts, video content, and interactive features.