Energy economics and air pollution


John Reilly, senior lecturer, MIT Sloan School and co-director, Joint Program on the Science and Policy of Global Change

Noelle Selin, associate professor, MIT Institute for Data, Systems, and Society and Department of Earth, Atmospheric and Planetary Sciences


The work that we’ve done in the past together has really tried to say, what policymakers are concerned about is the economy. If we can then think about impacts of air pollution on the economy as a percentage of GDP, that really gets a lot of people’s attention.

Noelle Selin: I’m Noelle Selin. I’m associate professor in the Institute for Data, Systems, and Society and also the Department of Earth, Atmospheric and Planetary Sciences. My research relates to air pollution, thinking about decision making and how air pollution travels in the environment and what health impacts that air pollution has.

John Reilly: I’m John Reilly. I’m a senior lecturer in the Sloan School, that’s where my appointment is, and I also am co-director of the Joint Program on the Science and Policy of Global Change. I work on environmental agriculture and energy economics. That’s what I’ve been doing and working on climate change for most of my career, which is now almost 40 years.

NS: I’m not sure I really have an updated picture of what the energy mix actually is from a statistics point of view. Why don’t we start with that and talk about what actually is happening now in the U.S.?

JR: I think that’s a good place to start, Noelle. I think there’s a lot of talk about wind and solar power and there’s been a lot of investment in wind and solar. But as of 2018, we still relied on fossil fuels for 80% of our energy and another 9% from nuclear power. There’s only 11% from renewables, and of that, half of that is hydro and geothermal, another almost quarter is biomass. Of those renewables, only about 25% is from wind and solar. That makes them contributing less than 3% of our current energy needs. As we look forward, if we think we’re going to rely on those more and get rid of fossil fuels, they have to grow a lot.

NS: But that differs a lot by region, right? Because that’s the average of the U.S., but here in Massachusetts, that’s different from, for example, California or the Northwest, right?

JR: Sure. In general, California has almost no coal, I think has virtually no coal electricity generation. Similarly, very little in New England. A lot of the coal use in the United States is in the central part of the country. But again, the electricity markets are kind of overlapped. Just because you don’t use the fuel in your region doesn’t mean you’re not necessarily responsible for the emissions in other regions, for example.

NS: When we think about the solar and wind penetration, that’s going to obviously vary as well, because some states have these renewable portfolio standards.

JR: Yes. But then also there’s a market for renewable recs as well. Again, states can put in renewable power, but it may be other states purchasing the rec. Even though there’s regional differences, there are national markets in these things that it’s hard to tell where the responsibility might lie. Of course, those states that put in their renewable portfolio standards then are creating a market for development for renewables somewhere.

NS: That makes it interesting to think about both CO2 and air pollution of the same time. Because you have CO2, where it doesn’t matter where you’re emitting, and then when you’re thinking about air pollution, like particulate matter in the atmosphere, it matters what kind of sulfur and nitrogen is emitted and where. Those two are really overlapping problems. It makes it difficult to figure out what happens when you put in a renewable standard, for example.

JR: It makes it an incredible difference. You know even more about that than I do, I think, Noelle. I mean one of my fascinating questions is, you mentioned that link between air pollution and climate, and when I’ve talked to atmosphere chemists like yourself, I’m always amazed at how complex and how many those linkages are. Maybe you could remind me what some of those things are.

NS: When you think about what happens from a power plant, let’s say a coal fired power plant, it’s emitting not only CO2, but it’s also emitting sulfur dioxide and its emitting oxides of nitrogen. Those emissions combined in the atmosphere and form particulate matter, PMT 0.5 is made up of sulfur, nitrogen, and ammonium. That creates an aerosol when we inhale it that is dangerous to human health. But it depends whether you’re downwind of that power plant or not, whether you’re affected by that, so it matters a lot where that power plant is.

JR: You say these particulate matter. You say they’re composed of different things. Does it matter what they’re composed of, in terms of the health effect?

NS: That’s a big question. The particular matter we’re most concerned with is the really small pieces, less than two and a half microns in size. That’s the fraction that you can inhale really deeply into your lungs and causes health impacts. It’s probably the case that different kinds of particulate matter have different health impacts, but it’s really hard to tell. There haven’t been really good studies quantifying that relationship between the composition of particulate matter and the health effects.

JR: One of the energy trends we have seen that we think has been a positive effect on CO2 emissions has been this big switch over the last decade away from coal and towards natural gas. Has that had a benefit in the conventional air pollutants that you’re talking about?

NS: Absolutely. When you think about the emissions that come from a gas plant, that’s much less than it comes from a coal plant. The more controls that you can put on and the less coal that’s in the energy mix, the better it is for air pollution.

JR: I know you’ve looked at mercury as well. Is mercury a particulate matter? How do we get exposed to mercury and where does that come from in the energy system?

NS: It primarily comes from coal in the energy system. It’s a contaminant of coal and when you burn coal, it emits mercury to the atmosphere. That mercury can be associated with particles, but it also can be in the gas phase. We’re actually not concerned with the concentrations of mercury that we inhale from, for example, an emitting power plant, but we’re concerned with mercury when it deposits to ecosystems, converts to methylmercury, and then we eat fish that has high levels of methylmercury. But the root of that really is coal.

JR: We’ve been worried about climate change and CO2 emissions and other things, greenhouse gas emissions. But some of the air pollutants have some effects on the climate as well directly, don’t they?

NS: Yes. Black carbon, for example, can be a climate warmer. The idea that you can potentially design strategies to mitigate CO2 and mitigate air pollution at the same time has been really attractive to policymakers. One of the really attractive parts of that is that you can have local benefit as well as global benefits. One of the problems with dealing with the CO2 problem is that any actions that you take now, you might not see the impacts of in your local area or on a timescale that you’re concerned with as a policymaker. But actions on air pollution can benefit people right away and nearby.

JR: We’ve both done some work in China and I think there’s a big debate, China made some different arguments, whether it’s a big commitment or a small commitment to reduce CO2 emissions. But I think there are some people that believe most of that interest wasn’t reducing air pollution. Do they really get credit for reducing CO2 emissions or not, if they’re going to do it anyway for air pollution? But I guess, in the bigger scheme of things, reducing it for whatever reason is a good thing. You’ve looked at China, do you have any perspective on some of those issues?

NS: I’m not sure whether you necessarily need the right reason, as long as you have both impacts at the same time. There’s better or worse ways to do that. You can take actions that don’t actually mitigate CO2 emissions. For example, putting in scrubbers might even increase the CO2 emissions, because it costs more energy to actually run those scrubbers. On the other hand, moving away from coal towards more renewables will have both benefits CO2 and air pollution.

JR: I think we did a study some years ago with a simplified model—I know you’ve used some really complex ones—where we ask, if you put a policy on to reduce air pollution, conventional air pollutants like your particulate matter items in China, what effect would that have on CO2 emissions? And vice versa, if you put a cap on CO2 emissions, what effect would that have on air pollution? We kind of said, if you set a policy, you get a 10% reduction in air pollution, does that give you a 10% reduction in CO2 emissions or a 1% reduction in CO2 emissions or what? What is this cross-relationship? Surprisingly, we found it was almost one for one. You get a reduction in both, even if you’re only aiming for one. But there can be some benefits of doing both, because there are probably are some technologies that would reduce one set of pollutants and not the other. I think there’s a big concern in China about developing coal gasification then using gas in the cities to reduce air pollution. But that coal gasification would have resulted in a lot of CO2 emissions elsewhere. That’s where you don’t get the double benefit.

NS: We’ve both done work that has illustrated that double benefit at the levels of CO2 emissions with the energy mix that we have now. The really interesting question, I think, is what happens when you start getting less and less CO2? When you start reducing CO2 to the levels that are consistent with, for example, the 2° target, how do you really optimize those strategies to think about both air pollution and CO2 simultaneously?

JR: My sense is if we really have to hit those targets, air pollution from energy is largely going to be gone. Because if we really have to hit those 2° targets, then we have to get to essentially zero emissions of CO2. If we’re not using any of the fossil fuels, then there’s not going to be any of the air pollutants associated with those combustion. Even if we’re using something like carbon capture in storage, I think that technology, in doing that, you remove all the other pollutants as well as the CO2. That will, I think, make the air pollution problem go away. At least from energy. We’re involved in a joint project together with Harvard, and in the recent meeting we had, I was struck by where some of the other pollutants… there are still other sources of some of those pollutants. Might you say a little bit about some of those?

NS: I was going to bring up agriculture, which is one area that you’ve worked in a lot. The ammonia that helps make sulfate nitrate ammonium aerosols comes a lot from agriculture. That kind of activity, which isn’t a power plant, can contribute to air pollution also.

JR: That’s the route that really surprised me. I wasn’t expecting that. I think the experience in California, really cleaning up power plants, which are the big source, and then cleaning up vehicles quite a lot, are now left with things like charcoal grills and powerboats and lawnmowers as the major sources of pollutants.

NS: Personal care products, too. Aerosols from things like deodorants, things with scents and various other kinds of cleaning products, that actually has a big impact. Some of the volatile organics from just other kinds of household sources.

JR: It’s interesting because we think about… as an economist, we want to put a carbon tax or pollution tax across all the sources and then we get reductions elsewhere. Oftentimes frequently people say, “Well, what are the big sources? Let’s just tackle those.” The issue is, once you tackle those, then you’re left with these little sources which are now the big sources. With the scale of humanity becoming bigger and bigger, more people, more economy, even those what were small things become big as we go forward. It’s a big challenge.

NS: One of the things that’s come out of our Harvard collaboration is the work that the Harvard School of Public Health has done in quantifying the impacts of air pollution even at lower levels. There are a lot of places in the United States that are still in compliance with air quality standards, but what the Harvard work has shown is that actually still has health impacts. We’re going to be dealing with air pollution for a long time. We could have some significant benefits even as we decarbonize the economy.

JR: It’s interesting, you probably know this history as well as I do. When the Clean Air Act was written, people thought there were safe levels of air pollution. The language is actually “there can’t be any impact on human health”, but as we’re finding, being able to detect the impacts of smaller and smaller levels, it’s not clear that there is any level where it doesn’t have some impact on human health.

NS: You have a bunch of different problems going on simultaneously with different timescales. For example, mercury stays in the environment for a long time. When we talk about a particulate matter problem, if we shut everything off in a few days, things will settle out of the atmosphere. But with mercury, mercury continues to cycle between the atmosphere, land, and ocean. Mercury will continue to be a problem. Because it’s an element, it doesn’t go away. Mercury will continue to be a problem for generations.

JR: When I first read your work on that, I was really struck by that. That is really a challenging problem. It’s a bit like the climate problem and long-lived greenhouse gases. Once they’re in the atmosphere, they’re there for a long, long time. You’re really stuck with them. Again, as you were talking about pollution effects on climate, there’s of course the bright aerosols, the sulfate aerosols are reflective. They’re currently offering a cooling effect. But if we clean them up really quickly, that will unmask the warming that’s there. These complex interactions are just constantly amazing me.

NS: As an atmospheric chemist, I think a lot about the timescales of interactions, the temporal and spatial scales. But economists do, too, right? As we think about how policy makers value these near term effects and long term effects, economists have thought a lot about that question.

JR: There’s this whole discounting issue. We think if you put money in the bank and earn 4% on it, you should think about the future. Instead of spending money today for something that’s going to only benefit you 50 years in the future, you can put that money in the bank today and earn money, then solve it when you get to the problem. You don’t have to solve it further ahead than you really have to. But with the climate change thing, there is this idea that the risks are in really the distant future. That was true when I started working in the area 40 years ago, but unfortunately it’s 40 years later and we’re actually seeing the effects now. I think they may be bigger than we actually imagined. Another aspect of this problem that I think is really fascinating, and I know you’ve worked on this, and that’s the environmental justice angle of it. I know you’ve done some work. Can you remind me of some of the results you’ve gotten on that?

NS: One of the things that’s well known in the U.S. is that populations that are lower income, populations that are minorities are highly exposed to air pollution, and differentially exposed. They’re exposed to more air pollution; they see more impacts than others. One of the things that our work showed was that the cost of this air pollution is also borne by low-income people. That was an important result because it says that if you mitigate air pollution, you actually can have an important impact on inequality.

JR: That’s been the concern broadly. Some of it is obvious. Wealthy neighborhoods prevent dirty industry from moving in and poor neighborhoods don’t have that political power, so they get the location of these dirty sorts of things. It’s a reinforcing circle that way. That’s a really important thing as we go forward. I know when we look at the climate problem and solving it, we realize that lower-income households spend a bigger proportion of their income on energy. If we think about having to make energy more expensive because we’re moving to alternative forms that aren’t as cheap, we really have to think about how we right the wrong making poor people disproportionately poor to solve this problem. Overall, wealthy people use more energy, but it’s a smaller proportion of their income. We have some ways of dealing with that: taxing—a carbon tax—and then rebates back to those poor households.

NS: I think that’s one of the really strong things about economists and atmospheric scientists working together, is that you can get a better sense of where the problems are, where possible solutions can be beneficial and get a better idea of who benefits from these solutions, which hopefully will actually get policymakers to act on them.

JR: We see these problems looming. We’ve made progress in air pollution over the past but if we don’t continue to get cleaner and cleaner, scale just keeps pushing us up. We have that problem. We have the climate problem. What’s your perspective on where we need to be in a decade or two?

NS: I think we really need to pay attention to the kinds of decisions that people are making to benefit society, both in the near term and the long term. Really finding these solutions that are win-wins, to think about how we can tackle the air pollution problem at the same time as tackling the climate change problem. Not have solutions that will benefit us now in the near term but sacrifice in the long term. Really understand those linkages better. I really view air pollution and climate as a case study example of a broad range of different kinds of sustainable development issues. If you think about, for example, the sustainable development goals of things like ending hunger and poverty, thinking about how you can benefit people in the near term without sacrificing the ability of future generations to live and thrive.

JR: I guess we economists have been as guilty of this as anyone. We’ve had trouble at times talking about what the exact benefits are. We’ve talked about the cost of policies and then it just looks like a lose situation in the immediate term for people seeing more expensive energy, and thinking maybe only about the long-term solution. But I think we are now trying—you and I have worked on it a bit—of trying to bring these health benefits and the environmental benefits back into the whole economic modeling framework so we can say, “There’s some costs of changing the energy use, but there’s a whole bunch of benefits over on the side of avoided health costs and avoided health effects.” The idea there is to have it be a win situation. It’s just that if people go to the gasoline pump and see higher gasoline costs, they aren’t automatically connecting that with cleaner air, but they should.

NS: I think it’s the idea that, historically, a lot of the framing has been more sacrificing in order to benefit future generations. But there are good reasons to benefit people who are here now. We can understand better the benefits of clean energy sources. We can convince people that this is something that is in their interest as well as the interest of the future.

JR: I’ve been around a few more years than you, Noelle. [Laughs] Going back to my days in graduate school and environmental economics, I think there was a perception that the environment was a luxury good, that was something that benefited wealthy people. But when we see problems like mercury affecting the IQ of children, and particularly poor children, or we see climate change or ozone pollution damaging crops and limiting food availability and raising food prices, that’s affecting poor people. A good environment isn’t a luxury good, it’s actually a necessity good, and actually probably has a bigger impact on the poor, as your environmental justice work is demonstrated, I think.

NS: Also, increasingly, I think we’re realizing the importance of the environment to really all sectors of the economy and how important having a stable climate is. That wasn’t really taken into account as much 40 years ago.

JR: I think the big move now—and we’re doing some work on this—is in climate finance and climate-related financial risk. A lot of the big banking institutions, Bank of England and others, are beginning to force banks to think about, “Are my loans and assets exposed to climate risk?” Either because they’re heavily invested in fossil fuels—which if we are no longer going to use them, are not going to be worth very much, so that may tank those assets—or they have big loans in flood prone areas and a lot of homes and mortgages go underwater both literally and figuratively. That forcing the financial community to look at these risks, I think will begin to percolate the recognition that you need to take these into account throughout a lot of the economy. Maybe I’m a Pollyanna, but that’s what I’m hoping.

NS: I think you’re increasingly seeing people planning for 10-20 years ahead. There are institutions certainly that plan on those timescales. MIT, for example, thinking about when our next generation of students are going to be at their 15th reunion. Basically, the class of 2020 will be at their 50th reunion in 2017. When we think about 2070, we think about that a long way away, but we saw the 50th reunion crowd coming here to MIT this past June. It’s easy to imagine that that would happen 50 years in the future for our current seniors.

JR: I’m actually involved with MIT and our building folks to evaluate the risks of climate change to MIT. There’s a big effort on the campus to, in the new buildings we’re putting up, make sure that they’re resilient to climate change. There’s been lessons learned in the Gulf where climate change came in and damaged a whole bunch of stuff that was in the basement or on the first floor. We’re doing an inventory at MIT. Do people have really unique and one-of-a-kind collection stored in the basement? You should get it up out of the basement, because if that’s flooded, then we’ve lost that collection completely. Are our electrical connections and utilities and generators located on the ground floor? Or do we have to move them up 10 or 12 feet, so in case of flooding they’re resilient? Then if we have storm events, what does that do to disrupt students and faculty in getting to campus? I think we should have started thinking this far ahead 20 years ago, but now thinking ahead, we can make adjustments in the building scheme as we go. Usually it doesn’t take that much more to build a resilient building. But if you build a building that isn’t, to fix it takes a lot. Thinking ahead really helps.

NS: People do plan on those timescales. We talk about policymakers thinking maybe a year or two ahead. But when you’re thinking about infrastructure, you’re really hoping it lasts for 50 years.

JR: We’re going to have to massively transform the energy system. Essentially, fossil fuels have to go away and we have to replace them with something else. I know wind and solar are the popular ones now, but I almost hate to say this anymore, but the sun doesn’t shine all the time and the wind doesn’t blow all the time. We have to fill in the electricity needs in between. There’s hope that there could be some storage technique, batteries or something, that could store power. But that’s still quite expensive and it’s likely to continue to be expensive. I think we have to look for lots of different options. Nuclear, one hates to even talk about it because of all the nuclear waste issues. Maybe that’s a place we can go. But it is a big challenge.

NS: What about the role of behavioral changes? Do you think that our use of energy, in particular the timing and the frequency of it, could change as well?

JR: As economists, we always figure the thing that changes behavior is price. If we raise the price of fossil fuel, then that will change people’s behavior. There’s hope that somehow we’ll become better and more conscious. There may be some hope of that. I think there are some big combined win-win situations. If we bicycled more, we’d be in a little better health probably, if there’s air pollution we’re breathing in while we do it. Or if we ate a better diet with less saturated fat and red meat. Cattle result in a lot of greenhouse gas emissions. We could maybe both solve the climate problem and have a healthier life. There’s possible things there.

NS: One of the things that keeps me optimism is to think about how large a change there’s been just within my lifetime on how we’ve used communications technology. Thinking about how we use the telephone before mobile phones and how we use the telephone now. It’s just completely different. The patterns of our lives, the ways in which we engage with that technology is just a lot different. In the early years, it wasn’t actually as reliable as a landline. But there were all sorts of different social factors that changed at the same time. Potentially, there’s room for people to adjust to a new reality in energy or in transportation as well.

JR: The slight difference is that the environmental impacts of that is what we call a public good. If we change our habits, the benefits flow to everyone and only a little bit to us. Whereas the fancy new communication devices, those are exciting and fun. We harvest all the benefit of that and enjoy those. Doing that is fun. Doing something for the good of everyone else is altruistic, but sometimes we’re a bit lazy on those.

NS: I think we can see potential innovations that could help in terms of gadgets. I think there are a lot of people who get really excited about their electric cars. There are a lot of people who get excited about their solar panels.

JR: I have both. [Laughs] I’ve actually been excited about my electric car. It’s a lot of fun. The acceleration is fantastic. It’s just smooth. I do drive a long way every weekend in the dead of winter and the battery runs out before I get there. I have to stop and do some fast charging along the way. It did take a lot of figuring out how to make it work. The first time I drove up to Maine, where I have a house, I got there and said, “I’m going to plug this in and hopefully it’ll be recharged by the time I’m ready to go back at the end of the weekend.” It said by 4:00 pm. It just didn’t say 4:00 pm what day. It was going to be 4:00 pm on Tuesday. I needed to install a fast charger up there, a faster charger, so I could get it charged. I’m the chair of my condo association, Electrical Vehicle Charging Committee, because we’re trying to figure out how we can get EV charging in our building. The building is kind of old, so the power lines are not enough and a whole bunch of issues. We’ve been working on that for two years. Fortunately, MIT offers EV charging here. I’m able to mostly fill up here and then up in my place in Maine, which is powered by PVs. I’m trying to do my best to actually walk the walk that I’ve been talking for 40 years.

NS: We clearly need policies that make things easier to do that. Subsidies for PVs, infrastructure for charging, et cetera.

JR: The infrastructure for charging, there have been a big commitment in the Northeast now to get that in. You got to get over that hump. Once you’re over that hump, it gets easier and easier. In these early stages it is making sure you’re searching for someplace near that you can charge. But soon we’ll be past that. The fast charging is getting faster and faster, so the technology thing will help as well.

NS: Transportation is a huge source of air pollution, so that will have good substantial benefits inside cities, which could actually address some of the inequality issues as well.

JR: The electric vehicles on conventional air pollution are probably even more important than on climate change. But that would kill those two birds with one stone if we go that direction.

NS: I think what I would say is that the energy mix. If we’re serious about climate change, the energy mix in the next 20 to 30 years has to be really dramatically different. That’s going to mean a lot of changes for both our environment, but also for where people get their energy and what they’re doing with it.

JR: I would encourage pioneers to try some of these new things and be a leader in your neighborhood. One of the things that prevents us from moving ahead is it’s hard to see doing something a different way. If you’re used to doing the thing the same way, using the same fuels and the same technologies, you don’t really want to change. People are busy. Everyone’s got a busy life and it’s hard to put a lot of mental energy on doing something different in the way you use energy. If you’re up for it and you’re a pioneer and can demonstrate some of these things, then maybe you’ll talk to your neighbors and say, “This was actually kind of fun. It was interesting. It wasn’t as bad as I thought. There were a few kinks when I got started, but those have been ironed out. You should really give this a shot.”

NS: Also, the role of being an engaged citizen as well. Thinking about how to push people who are in elected office to think about different groups of people and how they benefit or harm from different policies, how to think about people in future generations. Really prioritize what it’s going to take to make changes that aren’t going to protect the climate.

JR: And vote.

NS: Yes.

JR: The energy mix in the future will depend on what types of energy we need. There’s liquid fuels, there’s gas fuels, electricity, and solid fuels. Some of those have unique uses in different things, like one of the barriers to electric vehicles has been the having batteries that are light enough, that can store enough electricity and then they’re slow to charge. You only have to spend a couple of minutes filling up your car with gas, it’s very dense and you go a long way. Getting over some of those barriers are really critical. If you can get over those barriers, then a lot more electricity. If you can’t get over those barriers, then maybe it’s a liquid fuel but maybe from a different source, maybe from biofuels. From an economic standpoint, we’d like to let the market sort out which is the best option given this very complex system. That’s why we’d like a broad carbon price that would let things turn out the way that makes most economic sense, rather than target a specific mix. But that mix has to have a lot less fossil fuels, or possibly none, or we need to have carbon capture and storage with the fossil fuels we use.

NS: From a science perspective, you want to get to zero carbon. When I think about how these transitions will go, I really think about how different kinds of energy transitions and other kinds of transitions have happened in the past. What we see is they haven’t been smooth. They haven’t been just incremental. It’s hard to say what the winners and losers are going to be in terms of technologies. Setting the right conditions for those transitions to happen and making sure they happen in a just way that benefits everyone and not just certain people is important.

JR: The electricity sector has been interesting. There’s many waves of different things that have come in and then they’ve been replaced by something else. For example, we had a lot of coal generation first. Early on, hydro. In the early days, we took hydropower and turned it to electricity. Then we needed more and we have coal. Then in the 60s and 70s we thought nuclear power was the answer. You had a massive amount of nuclear power built in those years. Then with safety issues involving that, that came to a halt. Then we had a lot of gas generation built. It’s been wave on wave. The nuclear power started but then choked off. When we’ve looked at some studies of wind and solar, we see that you could get to maybe 40% of U.S. electricity supply with wind and solar where it would still match well with the patterns of demand. If you get up past that, that’s when you start running into this need for storage or demand management or other sorts of things, which ends up making it more costly. Then you’re looking for maybe another base load power, like nuclear or something.

What’s your current project, Noelle? What are you working on right now?

NS: One of the one of the projects we’re starting out is actually thinking about the nuclear idea. We have a lot of nuclear power plants that are ramping down or aging out of the fleet. We’re looking at what happens to air quality depending on what you substitute that with. There are a couple of different pathways you could go and substitute for the nuclear power generation with fossil fuels or you could substitute it for renewables. While many have looked at the CO2 implications of that, the air quality implications will depend on where and when those fossil fuels or renewables come online where they’re located. If we can think about this transition a little bit better, potentially we can get decision-makers at the state level to think about the implications of putting more fossil fuels in the system and figure out how the costs and benefits work out.

JR: Cool. We just completed a little study on nuclear power role in renewables and we had nuclear power gradually closing down and then you’d have to replace it with something else. We didn’t think too much, we let economics determine that, but one of the things we wanted to do as a follow-up on that is, what if we extended the license of those nuclear power plants? How much might that save the system if we didn’t have to build all new power plants? It’s funny that even though we haven’t talked about this, we’re working down the same direction.

NS: And as we think about scenarios, we want to be conscious of involving policymakers as well and what they’re thinking about. A lot of the decisions that are getting made are on the grid level, for example, and individual power producers, but also policymakers in different states who are setting renewable standards and companies that are investing in different energy sources.

JR: We talked mostly about the U.S. and a little bit about China. There’s a whole world out there. As big air pollution problems in lots of parts of the world, have you given much thought to that or what should we be worrying about there?

NS: We’re hoping to get some more research started in India, which has some substantial air pollution problems and hasn’t had as much regulation and activity and research as China historically. It’s a big country, a lot of population, and severe air pollution problems. I think we’re starting to see air pollution measurements in a lot of different places and really understand how severe the problem is in a lot of developing cities. There are increasing amounts of low-cost sensors that can actually measure air pollution in places where we don’t have an extensive monitoring network like we have in the U.S. and like there is in Europe. It’s a really dynamic field in thinking about what those sources are. Particularly intersecting with development, it’s really important to think about how you provide energy to people in a way that is going to protect their health and make sure that it actually has a net benefit.

JR: As we mentioned earlier, we had worked in China with Tsinghua University. They visited us a while back and are trying to get going a project jointly with us, suggesting that what made climate policy possible in China is that dual benefit of air pollution control and greenhouse gas control. They would really like to have us help take that lesson to other parts of the world. I think one of the things is, there’s 7 billion people in the world, what is it, two billion of them are in the U.S. and Western Europe and developed countries and the other five billion outside that. If they all consume energy like we do, the world is going to be fried and air pollution will be awful. We really have to jump them over the coal era. We have to skip that one and go to something else. We’ve had some discussions and we’ve had meetings in Africa and other places. When they look around, they see the cheapest fuels are coal or fossil fuels. But that’s, again, only looking at this cheapest and not thinking about the air pollution effects. I think we really have a lot of work we really need to do to bring this message that, if you just look at what you pay for coal in the cost of electricity, but aren’t looking for what the other costs of it are, then you’re going to think it’s the cheapest thing. When you start realizing you’re going to have more hospitalizations and healthcare problems and sick children and asthma and other sorts of problems from air pollution, you really want to rethink that choice. That’s a really powerful message, I think. Somehow we have to get together, Noelle, and do something about that.

NS: Certainly, the work that we’ve done in the past together has really tried to link that and tried to say, what policymakers are concerned about is the economy. If we can then think about what impacts those health effects have on economic productivity, then maybe we can speak the language that they understand. I think that’s a really powerful thing when we’ve actually quantified the impacts of air pollution on the economy as a percentage of GDP. That really gets a lot of people’s attention.

JR: I think we were able to do that in Europe, we were able to do that in the United States, we were able to do that in China. But it is trench warfare. It’s fine for India if you’ve done it for China, but is it true in India? It’s fine if you’ve done in the United States, but is it true in Mexico City? It’s fine if you’ve done it in Mexico City, but is it true in Santiago? It’s a big job. I hope we’re up for it.

NS: Also getting at the level of detail that’s really needed in terms of what specific policies can you put in place to make sure you get those benefits at the same time.

JR: Because they have to be relevant to the culture they’re in. One size doesn’t fit all. Cities have different aspects, they’re arranged differently, different transportation needs. Technologies can be used all over the world—cell phones are used everywhere—but there are some relevant aspects of really knowing what’s going on in the location.

NS: Different legal and regulatory permits as well.

JR: That’s why I think, the work we’ve done in China, we’ve worked very closely with people in China and other places. We have some expertise but we don’t have all the expertise we need here. Some of these collaborations are really critical.

JR: I think that’s the hallmark of a lot of the work that goes in the Joint Program on the Science and Policy of Global Change, that actually engages some of the stakeholders to think about what they really need at the front end. To think about how the research can be more useful and put it into practice.

JR: That reminds me, if you want to find out more about our program, it’s… what is it? [Laughs] I’ve forgotten now.


JR: That’s the Joint Program that I run, but Noelle is an associated faculty with it and a lot of her work is listed there. Do you have another site people can go to?

NS: Sure. You can go to Also, I’m on Twitter @noelleselin.

JR: Great. This is a lot of fun. Coincidentally, Noelle, I’ve become an air pollution expert. For some reason people read the articles I’ve written with you and I’ve gotten a couple of high school students write in saying… one student wanted to monitor air pollution and say, what is the average air pollution level in the fall in their city? I should have sent them to you but I looked online to see if you could buy air pollution monitors. They were kind of expensive and then they don’t really monitor ozone. I think they do mainly particulate matter. I looked at my iPhone and I saw that every day it tells me what the air pollution levels are going to be in terms of PM2.5, PM10, ozone, nitrates, a whole host of carbon monoxide. All the pollutants you know about. I suggested they just track them on their phone, but I guess their science teacher told them that was not enough. They went back to buy a monitor and actually measure them so they went back on that. Then another young woman was wondering what she could do to solve air pollution. I actually suggested maybe they not mow their lawn. I thought maybe that would be appealing, like, do less work and you’ll get cleaner air.

NS: I’m starting to observe the economics as well. I’m seeing the benefit of monetizing things to really communicate with policymakers in a language that they understand. Thinking about the costs and benefits in a more structured way and using more dollar signs.

JR: I think that’s one of the fun things about the Joint Program and MIT more broadly. The interaction we have across these different disciplines really enriches us. It’s always interesting to think that you can just throw a few answers over the fence from your discipline to the other side and they’ll be able to pick them up and run with them and know what they’re doing. Inevitably, I think we find that if you just throw those over the fence, people don’t know what to do with them or don’t understand some of the limits. You really have to work together.

NS: Absolutely.

JR: Noelle, this was great. I’m glad you could make it for this conversation.

NS: This has been fun.

JR: I’ve learned a lot from you over the years and probably a few things today.

NS: Yes, and I hope it continues.

JR: Thanks.

NS: Thanks.

Story Image: Air pollution smoke rising from plant tower. Observations of small atmospheric aerosols from JPL’s Multi-Angle Imager for Aerosols investigation will be combined with health information to determine the toxicity of different particulate matter types in airborne pollutants over the world’s major cities. (Credit: Public Domain Images)