On Climate and Common Sense—Sally Benson, Stanford University

collage of a wind turbine and solar panels with trees in the background
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Episode Notes

Sally Benson is a professor of energy resources engineering at Stanford University. The co-director of Stanford’s Precourt Institute for Energy, she studies technologies and pathways for reducing greenhouse gas emissions.

Sally came to Notre Dame to deliver the keynote address for the inaugural ND Energy Research Symposium. Afterwards, she and host Ted Fox talked about how much common ground there is to be found among the scientific community, industry, and all the rest of us when it comes to addressing the challenges posed by our changing climate.

Episode Transcript

*Note: We do our best to make these transcripts as accurate as we can. That said, if you want to quote from one of our episodes, particularly the words of our guests, please listen to the audio whenever possible. Thanks.

TED FOX: From the University of Notre Dame, this is “With a Side of Knowledge.” I’m your host, Ted Fox. The idea behind this show is pretty simple: A university campus is a destination for all kinds of interesting people, representing all kinds of research specialties and fields of expertise. So why not invite some of these folks out to brunch—yes, I said brunch—where we’ll have an informal conversation about their work, and then, I’ll turn those brunches into a podcast? It’s a tough job, but somebody has to do it.

For this episode, I had the opportunity to talk to Sally Benson, a professor of Energy Resources Engineering at Stanford University. The co-director of the Precourt Institute for Energy, she studies technology and pathways for reducing greenhouse gas emissions. Sally came to Notre Dame to deliver the keynote address for the inaugural ND Energy Research Symposium. Afterwards, she talked to me about how much common ground there is to be found among the scientific community, industry, and all the rest of us when it comes to addressing the challenges posed by our changing climate.

TED FOX: Sally Benson, welcome to the show.

SALLY BENSON: Well, thank you very much.

FOX: I feel like I’m safe making these assumptions, but please correct me if I’m wrong. Almost universally, scientists at this point would say humans burning fossil fuels are contributing to climate change.  There might be some disagreement to the extent that humans are contributing to it, but most scientists would say this is fact now. This is not a matter for debate. Would you say that is correct?

BENSON: I would say that’s absolutely correct.

FOX: We have a public discourse in this country that doesn’t always reflect that, whether it’s skepticism or whatever else.  I’m wondering how you as a scientist approach taking what you do beyond the scientific community? How do you convince people, or explain to people, that it’s in our best interest as a species to try to mitigate what is going on to our planet based on years and years and years of our activity?

BENSON: That’s really a great question.  I guess that I try to find common ground.  I think the common ground is that energy is very valuable for our lives. It makes it more comfortable, more interesting. It’s very important for our economy. If you’re in a low income country that doesn’t have access to energy, that’s a huge disadvantage, and we want to try to help people do that. So I start there.

And the other thing is, I know that there’s a sort of very visible public discourse that appears that there’s this huge polarization. But my experience is when you get people away in a quiet place and you talk about this, it’s mostly, “Well, yeah, we basically agree about these issues. We might disagree about how fast, how far, who’s responsible, how much we’re willing to pay.” But you’d be surprised how close we are in the way we view these things. So that’s what I hear.

One of my favorite things to do when I go to a new city and we’re often in a taxi or an Uber or a Lyft, I like to talk with them, and I’ll always ask, “Well, what about climate change? How long have you lived here and since you were a kid, have you noticed the climate’s changed?”  And almost everybody says “absolutely.” It’s either “more extreme events” or it’s just warmer or “we don’t have as much snow as we used to have.” So people’s personal experience in life is consistent with what scientists are observing.

FOX: I was wondering if you could talk a little bit about your two main lines of research in terms of carbon dioxide storage, as well as modeling and optimizing future energy systems to be more efficient. And, if you could, just give us an overview of those two lines and how they complement one another.

BENSON: For carbon dioxide capture and storage, the basic idea is, right now if we have a factory or if we have a power plant producing electricity, and basically we’re burning fossil fuels, part of what comes out of the smokestack, maybe 5-15%, is carbon dioxide. Instead of just allowing that carbon dioxide to go into the air, we can scrub it. So we can use chemicals just like we clean up other gases. We can scrub it out, we can compress it, and we want to make it so it can’t go back into the atmosphere.  The very best, safest place with the biggest capacity to do this is actually to put it back underground where the fossil fuels came from. Now that doesn’t mean you put it in exactly the same location, but again, you put it back underground. So that’s the basic idea behind that technology. It got going in earnest in 1996 in Europe with one project. Now, there are about 17 or 18 projects. So it’s growing. It’s not growing as quickly as we might like it to, but it’s growing. Part of the reason it’s not is that the capture process, the scrubbing it out of the smokestacks, costs money. It costs maybe about $100 a ton of CO2. We’d like it to cost maybe $30 or $40, and then it would be easier to do it.

The second part is when we put it underground, we want it to stay there. It takes quite a bit of effort to characterize the site to figure out whether it’s safe. So there’s work to do there. That’s sort of what I work on in terms of technology. And why I picked that? Couple reasons. I think it’s going to be very hard to stop burning fossil fuels. As a matter of fact, one might argue “well why should we?” They’re a valuable source of energy, the most valuable source of energy. If we can find a way to use them without emitting carbon dioxide to the atmosphere, that could be hugely beneficial. Then the other thing is, personally my scientific specialty is understanding how fluids move around in underground rocks. So two important reasons.

That’s one thing, but there’s not going to be any one technology that’s going to solve this problem. We’re going to need a whole bunch of things.  We’re going to need to simply conserve energy and just decide that we’re going to make choices: we’ll ride a bike instead of drive a car, we will air condition our house only when we’re in the house. And just think about conservation.  We will need to be more efficient. We’ll need to buy high-efficiency cars, high-efficiency air conditioners, have industrial manufacturing that’s highly efficient.  We need to do that, then we can do things like switching from using coal for electricity to using natural gas, that is half the carbon. We can use renewable energy, which has no carbon. We can electrify our cars. If we have electric cars, and they are running on the power grid that has low carbon intensity, that’s very beneficial. We can use carbon capture and storage; we can use nuclear energy. Then there are going to be these things that we don’t even know what they are yet. 

The question is, what’s the right mix of those things? Should we be 80% renewable energy and 5% carbon capture and storage? Or should we be 80% carbon capture and storage and 20% renewable energy. What is the right mix? And it’s going to depend on economics. It’s going to depend on where you are in the world. It’s going to depend on which resources you have available to you, other national priorities, national security.  There’s going to be a whole bunch of factors. The energy systems analysis that I do tries to give us answers to those kind of questions. What is the blend of all those things that can quickly get us on a de-carbonization path? And then keep us on a path that will make it so that the next reduction we need is easy to do. We don’t want to run into any dead ends where we sort of commit ourselves to infrastructure or systems that become inflexible. A good example would be in Germany where they basically have 50% renewable energy and 50% coal, and they’re having a hard time getting unstuck.  Actually they haven’t been able to reduce their emissions, because they shut off their nuclear plants, and they don’t have much natural gas, so they’re kind of stuck, and the next thing they need to do is very costly. So I want to try to understand how do we do de-carbonization in such a way where we don’t get stuck, because we have a long way to go, and we have a lot of work to do.

FOX: It sounds like it’s not even a question of will it be there, but should we be walking away from fossil fuels? It sounds like you’re saying, 50 years from now, 100 years from now, we aren’t necessarily saying we need to abandon fossil fuels altogether, but there’s clearly better ways that we could be using them and trying to figure out to what extent we can use them and make them so they’re not having the effect that they have been on our atmosphere.

BENSON: Right. Absolutely. There are certain things like making steel, making cement, making aluminum. There are things that fundamentally have carbon emissions associated with them, in some cases because they need fossil fuels. In other cases, it’s just a part of the process like cement and aluminum manufacturing. We’re not going to stop using those materials.  And maybe we’ll figure out alternative processes, but maybe we don’t. We just don’t know. And flying airplanes, how are we going to do that? Running ships, how are we going to do that? So yes, I can see for a long time, needing to keep some fossil fuels in the mix.

The other thing is what happens when we go for a week, or two weeks, and there’s no wind or it’s overcast and our solar resource is bad. We’re not just going to say “let’s all take a holiday.” We’re not going to do that. So as we de-carbonize, we need to maintain the resilience of our energy systems. Fossil fuels will probably play an important role in that, especially de-carbonized fossil fuels.

FOX: I’m glad you brought up that challenge of intermittency. We have wind power, but it’s not windy right now.  In an upcoming episode, I’ll be talking to Hendrik Hamman from IBM Research, that’s part of what he does with big data, is try to make the grid more efficient. He gave me an example of right now, if it’s 2% of the energy coming from these renewables, we’ve got it covered. But if you say, now the grid is going to be powered 20% by these, then it’s a bigger question. I was wondering from your perspective, is that the biggest challenge to the deployment of renewable energy or are there other challenges just as big that we need to figure out in order to get the renewable energy as a larger part of our energy consumption, or in a broader sense just as a society?

BENSON: I think that right now wind power and solar PV electricity, they’re actually both really cheap. If you look at something called the levelized cost of electricity, that means how much it costs to produce a kilowatt hour of electricity, it’s pretty much the same as natural gas, which is our lowest cost source. The real challenge of renewables is how to integrate them into the electrical grid. So our electrical grid is a miracle. Can you imagine anything where, at all times, supply and demand has to match each other exactly? Now in the old days, when you had generation from a coal plant or a gas plant or nuclear plant, you were completely controlling how much power you were producing. You watched what the customers were doing and the grid operators were fabulous at basically using a system of electronic controls and then picking up the phone and saying, “We’re going to need you to turn on your generator an hour from now.” They understood people’s consumption, and they were able to do it.

Now we’re saying we want to add renewable generation. Everybody knows when the wind is blowing, it doesn’t blow perfectly steady. It goes up and down, up and down. With the sun, a bank of clouds could come by, and you might have half of a day being sunny and half of a day being cloudy. Now we have to try to maintain that same 100% continual balance, but we’ve got a supply that’s varying. So how do we accommodate that? Basically, we have to have another supply that we can turn up and down exactly when the other one is fluctuating. So that’s the challenge. You can add in storage to the system, battery storage or other forms of storage; that can help some. You can start controlling demand. There’s something called demand-side management that says, “I’m a customer and when there’s a little bit of lag in supply, I’ll just cut back my use.” Maybe I can get my refrigerator to do that automatically. Maybe I can get my lighting to do that or my air conditioner to do that automatically. Or maybe if you want a bigger response, you can work with industry to say, “Well, we’d like you to make a guarantee that if we need the power we were selling you that you’ll stop using it within five minutes”. So those are the kinds of things that we can do. Like you said, if it’s 2%, no big deal. Ten-percent, 20%, it’s not that big of a deal but you get up into the 30%, 40%, 50%, it starts to be a big deal. And that’s the experiment they’re doing in Denmark, they’re doing in Ireland, we’re doing in California, south Australia. We’re getting to have higher and higher penetration of renewables, and we’re learning how to do it as we go. I would say overall for the experience in California, we have 30% renewables on our grid right now. I can’t think of a blackout we’ve had due to the variability. But it does cost. Because it’s not just the cost of generation now. We also have to think of how we deal with these shortfalls. If you need to buy storage, that costs money. The extra controls you need, cost money. So it’s also a matter of cost and how expensive it will be to integrate these renewables into the system.

FOX: You mentioned there a minute ago about partnerships with industry. And I know at Stanford, at the Precourt Institute of Energy where you’re a co-director, you all are managing a really new initiative, the Stanford Strategic Energy Alliance that I know is a partnership between faculty at the university and corporations. Can you talk a little about that and what the aim of that partnership is?

BENSON: At the end of the day, academic professors are not going to go out and run the grid, and they’re not going to scale up the next great device. It’s really industry who’s going to do this. It’s going to be industry, policymakers, and it will be our students, because they go out into the world. If the ideas we are developing are really going to get some traction, we need industry partners to help us understand the factors that will make it more or less difficult to implement those kind of ideas. We really rely on their advice for thinking about, what do we need to fix as we’re improving the technology.

And then at the same time, they’re learning from us at the very early stages. It’s not like they’re going to wait until we have something and “oh, here it is, take it.” They’re watching it as it goes along, and they’re making internal assessments. Is this a business we could do? And if it is, and they get excited about it, they’ll build their own internal research teams. They’ll start scaling it up in their company.  And at some point, it’ll be ready to go. It’s that close partnership, because throwing things over the wall or dangling them through journal articles doesn’t work. Our goal is really to accelerate the uptake of innovation, so that it can become deployed more quickly.

FOX: I like that you mentioned the role of industry, because there was a quote that you had in announcing the Stanford Strategic Energy Alliance that stood out to me. You said, “Throughout human history, fundamental changes in the way we use energy have unleashed the next level of society’s growth. Born of necessity and opportunity, now is one of those moments.” And it struck me because much of the time that we talk about renewable energy, we talk about de-carbonization and all these things. We talk, with good reason, about the impact on the planet and what’s going on with our planet, and being a good steward of our planet. But, as you alluded to in what you said, there’s also tremendous economic upside there. The potential to create new kinds of opportunities that maybe, not only corporations, but workers maybe haven’t had before in these new industries. Can you talk a little bit about some of those real world opportunities? I don’t want to call them real world opportunities, but I can see how sometimes you’ll say, “That’s great, you want to protect the planet, but what’s it going to mean for people’s jobs, and how companies are going to function?”

BENSON: Well maybe I can start with the topic I’m most passionate about. If you look at low-income countries and you look at middle income countries, particularly rural populations, they don’t have electricity. And they haven’t. Or if they do, it’s often highly unreliable, and it’s not sufficiently good that they can start using energy to make productive products to grow industry. So the opportunities for off-grid electrification in many parts, right now, there are 1.1 billion people who have no access to electricity. It’s huge, that’s three times as many people who live in the United States have no access. For about another billion, the quality is so poor or simply unaffordable. So it’s a good fraction of the people on the planet. I think that’s where a huge opportunity will come in. So I like that one a lot.

I think another area is in information technology. If we look at the way our electricity system runs right now, it’s remarkably simple. You produce power, you have a bunch of lines, and it’s almost like water flows down a hill. Well, the power systems people will be wanting to shoot me right now, but some of the basic physics is it just flows from where you have high voltage to low voltage.

There’s a huge opportunity to incorporate electronics into our electricity system to make it operate much more flexibly, so we can do all this demand-side management. We no longer are trying to operate a system where we at all times provide all the supply we need that both are fluctuating. I think for entrepreneurs, that’s an enormous opportunity.  Because the IT sector has transformed everything they’ve touched. Well, they haven’t really touched electricity, so I think there’s a huge opportunity there.

I think there’s a huge opportunity in vehicle electrification. Entrepreneurial opportunities in infrastructure, charging infrastructure, using our cars as mini power plants when they are plugged into the grid. Not only can they take power, but they can give power back. They can help manage the variability of the grid.  I think imagining transportation in a different way where we have electrified, autonomous, shared transportation infrastructure could be really transformational. Imagine waking up in the morning, going to your iPhone, and saying, “Pick me up at 8” to this autonomous car. You walk out the door, it’s there, two of your neighbors are in the car too. You get to drive to work, chat with your neighbors, and after going to work all day, your kid needs to go from school to your sister’s house, and the car picks them up. You can just imagine a world where shared infrastructure is the quality is better, it’s more convenient, it costs less.  So I think there’s huge opportunity there.

FOX: You’re talking about technology there, and I loved when I was looking at your work, I saw one of your colleagues, who I think is a postdoc at Stanford now, was doing something where it could potentially pave the way for these air conditioners with something called radiative heating, where literally the air conditioner unit, if it’s a clear day, can shoot the heat into outer space, which I thought was really cool. And from the outside, it’s something you would never think, “I bet we could do something like that.” And I was wondering if there were any other technologies that you’ve come across either in your own work or just in your own reading that you look at and say, “It’s just kind of cool that these are things we’re considering.” Because we think a lot about electric cars, which are neat, but it seems like there are some really innovative ideas out there that maybe the general public wouldn’t always be aware of.

BENSON: Well, I’ll use one. It’s not a super glamorous example, but it could have a huge impact. Right now most of us, or many of us, use natural gas for heating, which has a lot of carbon associated with it. Actually for most households, that’s actually the bigger source of carbon emissions compared to electricity. We focus so much on electricity, but really it’s heating, and there haven’t been a lot of ideas. So it turns out you can electrify heating.  You can imagine a system where neighborhoods have a district heating system. If you look from household to household, you might very well find that one house is heating and one house is cooling, and they’re doing it simultaneously. If you could take the heat out of the hot house and put it into the cold, and you can heat exchange, you can make more cold and more hot, and by doing that efficient heat exchange, you can reduce your energy demand.  We’ve done this at Stanford, we’ve reduced our energy demand by 70%, which is huge, absolutely huge. Then you make big tanks, you have a hot tank and then you have a cold tank. If you have too much hot at one time, you can store it, and you can use it at night. If you have too much cold at one point, you can save it, and use it the next day. So you can have a very efficient all-electric heating system district-wide. And again, it’s inexpensive because you’re using so much less energy. And they’re so much less-polluting because they don’t use carbon.

FOX: We at Notre Dame have installed geothermal wells to help with heating and cooling the buildings. Every time I go to understand how a geothermal well works, I get about two paragraphs into the explanation, and I feel like my eyes start to glaze over a little bit. So I’m wondering if you can give me the CliffsNotes version of how a geothermal well works?

BENSON: Geothermal systems can work in different ways. The simplest model is that you drill a well underground, and if you go deep enough, the water is fairly warm. You can just take that warm water, and you can basically use it to preheat water that you would otherwise put in a boiler. Or you can take water directly and run it through pipes for a heating system. So that’s the simplest one.

The next kind is something called a heat pump. The way a heat pump works is that you have something that’s cold, typically the air in a building, and you have this warm water, so you have a temperature difference between the hot from geothermal and the cold. Then if you run a compressor, you can basically take heat from the colder air and add it to the hot water, so you make the hot hotter and the cold colder. That’s basically the idea behind a heat pump, and sometimes they’re called heat recovery chillers. So again, you take a temperature difference, add electricity, and you make the hot hotter and the cold colder, and now you’ve got your two sources of cooling and heating simultaneously produced from the same energy source. So it’s super-efficient.

FOX: That makes more sense. I know that you were on the task force for the former Secretary of Energy looking basically at strategies for how we deal with climate change. I also saw that you had a letter with your co-director at the Precourt Institute talking about this idea that in order to solve, or address, a problem like climate change, we really need to embrace innovative solutions and embrace a culture where it’s okay to fail, because we have to think big. When we’re talking about what sounds like an energy future, where it will have a lot more strategies and a lot more sources of providing energy than we have today, is that central to being able to realize the future? Because it sounds like we need to be a lot more creative than we have been in terms of how we think about tackling how we supply the world’s energy needs.

BENSON: I think that’s just right. The energy system is huge. About 10% of the global economy is basically tied up in our energy system and the infrastructure that goes in it. This is a true story, so when you produce oil up in Canada from the oil sands there, it’s only about one week later that it has travelled from Canada down through the United States, ends up in the Gulf Coast, goes through numerous chemical processing steps, and becomes the gasoline you put in your car.  That is incredibly complex, all of those steps, and there’s just this gigantic machine that’s producing the power. And the electrical grid, which has been called the most important technological innovation. So people who are engaged in this realize how hard it is and how complex it is to keep this thing running the way it is, and when things are that complex and that big, we tend to think “Oh my gosh, we can only change super slowly.” It’s hard to imagine adding renewable energy, because it’s variable and intermittent and all of that.

The point of that article was that if we keep thinking that way, we’re not going to innovate. Sometimes people might not get it all right. There’s a lot of discussion about 100% renewables today as an aspiration. You can look at that and say that’s absolutely crazy, but you can look at that and also say directionally, that’s a good thing. It’s nice to know that somebody’s dreaming of that. Embracing innovation is looking across the full spectrum and wisely making the choices about the direction, the pace, and the options that we choose to pursue. If we’re going to de-carbonize as quickly as we need to, we need to have every single sector of the energy system contribute the way it can. To say to certain aspects: no nuclear, no fossil fuels, no carbon capture and storage, what we’re doing is we’re saying to 80% of you, “This is what you’re working on today, and we’re not looking for your help”. I just can’t think of anything more ridiculous than doing that.

FOX: Sally Benson, this has been a pleasure, and thank you for explaining all kinds of things to us. I appreciate you making time for the show.

BENSON: I’m happy to be here, thank you.

FOX: “With a Side of Knowledge” is a production of the Office of the Provost at the University of Notre Dame. For more, visit https://provost.nd.edu/podcast.