Everything you need to know about heat pumps

Jordan: When we talk about climate misinformation, we usually think about denial, that the climate’s not changing or if the climate is changing, then we didn’t do it, and if we did well then it won’t be a big deal. That kind of stuff. But there’s a more insidious kind of misinformation out there. The stuff that makes us think we don’t have solutions, that we can’t fundamentally change the way we do basic things that whatever green technology is blossoming simply won’t do what the fossil fuels we’ve always used have done. You are likely familiar with this kind of thinking from the discussion around electric vehicles, but there’s another even bigger fundamental shift at play. It involves changing the way that we heat and cool things for the first time in the entirety of human existence. That’s the kind of radical stuff that we’re talking about here. That’s the kind of radical stuff we’ll need and yet still ask people about it and you might hear that it just won’t work. Today, we’ll explain how it does. I’m Jordan Heath-Rawlings. This is The Big Story. Matt Simon is a senior staff writer at WIRED where he covers biology, robotics, and the environment. Hey Matt.

Matt Simon: Happy to be here. Thank you for having me.

Jordan: You’re very welcome. And I know this is a simple question, but how have humans typically or exclusively, I guess, heated their homes throughout all of human history until recently?

Matt Simon: Yeah, I think it’s actually a quite fascinating question because we’re in a really profound transition here. So throughout human history, we have burned things to stay warm. So would charcoal dung, sometimes these sorts of natural materials that we combust in order to produce heat. That is fundamentally shifting with the proliferation of the heat pump, which is distinct from something like a gas furnace in that it is transferring heat from outdoor air into the indoor space, even freezing outdoor air. It can do this that in of course contrast to what a furnace does, which is burn natural gas. So instead of burning things going forward, we’re going to be transferring heat. It’s this perhaps simple thing to think about in human history, but it’s actually a really profound transition that we’re in right now.

Jordan: I want to ask a little more about how that actually works, but also first, just because we’re going to be calling it a heat pump, people also use these things to cool their homes. It changing the way we cool homes in the same profound manner.

Matt Simon: It certainly is what a heat pump can do in the summer is circulating refrigerants and it’s changing the pressure of those to extract thermal energy from freezing outdoor air. When I say freezing, I’m talking the newest models are well below zero degrees Fahrenheit. That’s their continuous operating temperatures. This is a persistent myth that I assume we’ll get to here about heat pumps is that they do not work in cold weather. Not only do they work in cold weather, they work in very hot weather. So in the summer, these sorts of processes reverse and it can actually function as an air conditioning unit. So this makes it a very, very powerful tool when it comes to equity and climate change. So if we have people in cities in particular that are experiencing ever hotter temperatures, if we deploy as many of these heat pumps as we can, we give people not only clean heating during the winter time, but these folks may not have ever had air conditioning before. All of a sudden they have a device that does both. That makes it extremely powerful when it comes to decarbonization and keeping people healthy as the planet warms.

Jordan: As we’re talking, we’re about to head into summer, there are heat waves already in various places around the globe. These are only going to get worse, especially in major cities. How do heat pumps help with this and how ready are we for that?

Matt Simon: Major cities have this additional problem where it’s called the bourbon heat island effect. What happens is the built-in environment kind of stores that solar energy and it releases it slowly through the night. That keeps temperatures often 10, 15 degrees Fahrenheit higher in urban areas than in surrounding rural areas. So we have this opportunity now that if we are deploying heat pumps that provide heating and cooling, we are giving urban dwellers a way to cool down, especially as urban temperatures rise in lockstep with global temperatures rising. This is a major public health concern going forward. People already die from extreme heat in cities. If we can get more of these units in more homes, that’s really going to help save lives.

Jordan: Give us a little background. Where did this technology come from? How did it evolve to where it is today?

Matt Simon: It’s been around for decades. Honestly. I come from a long line of HVAC workers, so my grandfather owned an HVAC company. This is heating, ventilation, air conditioning. He then passed that along to my aunt who currently runs it. My father was an HVAC technician for his entire career. So I had always heard about heat pumps. Actually back into my childhood. They were installing gas furnaces, but also every once in a while a heat pump, and I never fully understood what that was until I got to WIRED and started reporting on them. So this has been on the market for many, many decades. It is becoming more popular. One because the price has been coming down with any technology. As it develops, it gets cheaper. But now we have something like the Inflation Reduction Act passed a couple of years ago in the United States that provides thousands of dollars in tax rebates and credits to install these things and to potentially work on the electrical system in a home to upgrade it to be able to run a heat pump. So yes, the technology is an old one actually. The issue has been that natural gas has been very cheap all that time, and it has been cost effective to burn that gas in furnaces, of course, to the detriment of the planet and human health.

Jordan: How much of a difference environmentally speaking, does a heat pump make from using natural gas? Can we quantify that and can we quantify it at scale?

Matt Simon: We can. Actually, there was a study that came out just this past February that tried to quantify this to look at, okay, theoretically in the United States, what if everybody got a heat pump? It would of course be good for providing that heating and cooling whenever you’d need it, but they calculated that it would cut the emissions in the residential sector by something like 36 to 64% and then cut overall emissions in the United States by five to 9%. These are profound impacts on the amount of carbon that we’re putting into the atmosphere. So the overall goal here is that we are going to have an electrical grid that is increasingly loaded with renewable energy, so wind and solar in particular. If we can get more heat pumps hooked up into that, they will be running on clean energy and it will be a zero emissions technology. That is the ultimate goal and getting that out into more homes in the United States, we’re going to have some help from the inflation reduction act, but also just by awareness, more people learning about these things that could very well make their home not only more comfortable, but massively slash their emissions and reduce their costs. It’s fundamentally more efficient to move heat like a heat pump is than it is to combust heat.

Jordan: You mentioned the inflation reduction act. I should add for our listeners that there are similar rebate programs available in Canada, either through various provinces or through the federal government at various times of the year. Cost is one thing. If this is so impactful in our fight against climate change and is also more efficient and cheaper in the long run, why aren’t these things everywhere and what are the other barriers aside from just making it possible for people to afford them?

Matt Simon: Sure. I think it has been largely an awareness issue that because again, natural gas has been so cheap, folks have just kind of defaulted to burning gas in a furnace. I’ve also heard anecdotally from folks that technicians that are doing this HVAC work aren’t really recommending them a lot of times.

Jordan: Why not?

Matt Simon: It’s the myth that they don’t work in cold weather. So this has been a persistent myth for decades now. I published a story about this last weekend in WIRED breaking apart this myth that we have extraordinary numbers of these heat pumps rolling out in Nordic countries, which suffer the most extreme winters in all of Europe, Finland, Norway, Sweden are deploying enormous numbers of these. So more than half of households really have heat pumps now, and because they have gotten much more efficient over the years, they have been able to run in colder and colder temperatures. They’re selling like hot cakes in Alaska, Maine just reach their goal of deploying a hundred thousand of them several years ahead of schedule. They’re not warm climates, at least in the wintertime. So that is a myth that needs to be blown up as much as we can because the way that these cold climate heat pumps work is pretty astonishing and the amount of thermal energy that it can extract from even very, very cold air. And then if it gets extraordinarily cold, we’re talking like the far north of Canada. These devices come with backup electric resistance, heating. It’s essentially a space heater that then kicks in and provides heat for the really extreme temperatures that almost nobody is experiencing. A heat pump can still manage that.

Jordan: Where did this myth come from and why does it persist?

Matt Simon: I do not have evidence for this. Let me just say that to be clear.

Jordan: We quantify, we got to qualify it with that. This is speculation.

Matt Simon: This is speculation, but I would not be surprised if there was some sort of misinformation from the fossil fuel industry about the cold weather issue in particular. We just need to look to these Nordic countries and to places like Alaska to see that they work perfectly fine in cold weather. Otherwise they wouldn’t be rolling out in these sorts of numbers. And I think it is probably been also this sort of entrenched mentality in the HVAC industry that if you have these technicians trained for many years on these fossil fuel systems, they might not think that this is an option and they might not think that it’s worth it for them to retrain on these systems. It will take one to two days for a traditional HVAC installer to retrain to install heat pumps instead. It works essentially exactly like a air conditioning system. You have a unit outside and a unit inside. It’s not all that different. So we are going to need in the United States and likely in Canada as well, massive retraining programs. It’s already starting to take off this realization that we need a much bigger workforce to roll out these green technologies in general, but heat pumps in particular because it is such a powerful lever that we can pull.

Jordan: What about the challenges of truly scaling up so that these are the primary heating and cooling machines for homes, but also do we make larger ones for office buildings and are our electrical grids prepared for the added strain? I know there are places in the United States, also in Canada that it’s at a premium right now space on these grids.

Matt Simon: Sure. These can be parallel evolving technology. So in order to get the most out of a heat pump, we of course want it to be running on pure electricity from renewable sources. Ideally, you do not want to be getting your electricity from a coal-fired or a gas-fired power plant. I will just say that even if you are getting your electricity from fossil fuel sources, because heat pumps are so efficient, it’s a sort of net benefit. But the ideal is yes, we have a grid that evolves in lockstep with the amount of electricity that we will be demanding going forward. I think something that’s hard to wrap our heads around is that going forward we will be consuming more electricity instead of less of it, but we will be getting the electricity from clean sources like wind and solar. What you’ll be seeing are these interesting ways that the grid will store energy. So I wrote a story a couple of weeks ago about this program here in Oakland, California where they are hooking up school buses to the grid to of course charge, but they have a specific technology that allows them to discharge back to the grid. This is called vehicle to grid technology. In the future, I would not be surprised if every electric vehicle on the road has this technology. So when demand peaks, that’s typically in the late afternoon. As people return home and switch on other appliances, we’ll be able to draw energy from a sort of distributed network of electric vehicles. School buses are great because they’re on a set schedule, obviously, and they have giant batteries. So we will be storing more electricity, we’ll be using more electricity, we’ll be generating more from renewable sources. That will be what will power the heat pumps and we’ll have a truly clean sort of way of living in a home that we haven’t been able to enjoy before.

Jordan: How difficult will the information war around these quickly evolving technologies be? First of all, you mentioned retraining and educating service technicians and that kind of thing, but also just dispelling the myths that we talked about and how do we combat this stuff at a time when obviously we need these new technologies and they’re also kind of becoming more complex and evolving faster day by day. So it’s kind of hard even for people who dabble in this stuff to keep up.

Matt Simon: It’s the incentives. So I should have mentioned with this vehicle to grid technology, the utility is paying you as you are discharging your electric vehicle into the grid. It’s very early days of this technology and utilities are still working out rate structures here, but the idea will be if there’s peak demand on the grid and the utility needs that energy from you, they will pay you to slightly discharge your battery. And the beautiful thing about this is that as it scales, we’ll need to take less and less from any one battery, right? So if you have 2 million vehicles, you need to drain less from each of those than you would if you were running 500,000 vehicles or whatever the case may be. So it’s the incentives for paying people for the battery power that is just sitting in their garages hooked up to the grid, but also for incentivizing heat pumps. So because it’s expensive sometimes to put these in. 15, $20,000 if you are getting some of the larger heat pumps that are working in the depths of winter. So we need much more government support from that. We’re seeing more of that in the states, not only from the federal government, but from states. And it’s about educating folks on the benefits here of a heat pump, not just for decarbonizing the home and saving money, but for improving public health inside the home. If you’re not burning poisonous gas, you’re better off for that.

Jordan: But in general, as somebody who understands these technologies thoroughly, when you go out into the world and talk to people who don’t work in this space, how well versed in it are we compared to how fast things are changing?

Matt Simon: What’s actually going to help here is new ways for deploying heat pump systems that are much simpler for the consumer to understand. And I’ll talk about two different ones here. One in the New York City Housing Authority, they are deploying heat pump units that slip over window sills. So think of the classical air conditioning unit in the big city in an apartment that’s stuck in the window. They’re now making heat pump versions of that, and they’re deploying them first in these public housing units. Again, providing people not only clean heating during the winter, but also air conditioning if they’ve never had that before in the summer. And those are units that are being provided to those people for free and because the city housing authority is paying for the utility bills as well. So it’s a perfect kind of deployment. Those window units will become, I think, much more available in the coming gears for other consumers. It’s a cheaper way to heat a single room. If you have a smaller apartment, a larger home might need more ducting and bigger units for that. There’s also another company called Quilt here in California that is working on this sort of system that it’s the same principle. Only there units attached to walls, it can detect when you’re in the room. It’s these more simple kind of out of the box solutions that are going to help the heat pump proliferate, but so much of it is going to be an information war, pushing back on the myth that heat pumps don’t work in cold weather. Yes, they most certainly do. And yeah, it’ll be for everyone’s benefit going forward except for the fossil fuel industry, and I’m perfectly fine with that.

Jordan: Matt, thank you so much for this really insightful. I hope it helps dispel a few myths.

Matt Simon: Sure, yeah. Thank you for having me. It’s been great.

Jordan: Matt Simon is a senior staff writer at WIRED. That was The Big Story. We got all the big stories you could ever want to listen to at The Big Story podcast.ca. You can search for anything that interests you. There’s a little search bar at the very bottom of the page. You can avail yourselves of that. You can also give us feedback by sending an email to hello@TheBigStorypodcast.ca or by leaving us a voicemail when you call 416-935-5935. The Big Story is found everywhere good podcasts are found, and wherever you find it, it would be lovely if you’d leave us a rating or a review or share it with a friend. Thanks for listening. I’m Jordan Heath-Rawlings. We’ll talk tomorrow.