Rajasekhar Balasubramanian
Description: Rajasekhar Balasubramanian is a Professor of Civil and Environmental Engineering at the National University of Singapore. His research looks at environmental sustainability, air quality & pollution control, and waste-to-energy conversion methods. In this episode we talk about the often-overlooked impacts of indoor air pollution, the barriers to a green economy, and the potential use of biomass-waste for energy generation.
Websites:
Publications:
Resources:
Sustainable Urban Development Second Major
Book Suggestion:
Show Notes:
[0:00:01] Introduction
[0:03:30] Balancing Time and Responsibilities
[0:03:42] Collecting Cloud Droplets for Research
[0:06:35] Unraveling the Chemistry of Acid Rain
[0:12:12] Adapting Research Methods in Singapore
[0:15:40] The Impact of Indoor Air Pollution
[0:20:24] Understanding the Complexity of Air Pollution
[0:26:17] Indoor Air Quality and Pollutants
[0:29:20] Mitigating Indoor Air Pollution Exposure
[0:33:28] The Benefits of Phytoremediation
[0:34:46] COVID-19 Impact on Air Pollution
[0:39:14] Engaging Policymakers for Change
[0:42:55] Overcoming Challenges for Green Economy
[0:53:14] Converting Biomass Waste to Resources
[0:59:21] The Energy Potential of Methane
[1:01:13] Utilizing Activated Charcoal for Purification
[1:01:26] Innovative Absorption Technologies
Unedited AI Generated Transcript:
Brent:
[0:01] Welcome, Professor Rajasekhar Balasubramanian. Thank you for coming on today.
Rajasekhar:
[0:06] Thank you very much for the opportunity to have a conversation with you both, Kent and Kramer. And what you guys are doing is truly amazing.
And the efforts you put in to bring the global community together is highly commendable.
Brent:
[0:20] Thank you.
Keller:
[0:21] Thank you. So we'd love to start off by hearing a little bit more about your background, how you got to the National University of Singapore, and what got you interested inenvironmental engineering.
Rajasekhar:
[0:30] So, it's a very long answer. I will try to make it short for you.
Well, prior, I joined the National University of Singapore back in 1996.
So, it's almost 28 years since I joined the university. But back in 1996, as you probably may not know, that the U.S.
Was actually a teaching-intensive university that it transformed itself since 2000 to become a research-intensive university.
So before 1996, I was actually in the U.S.
Working at the New York State Department of Health in Albany doing full-time research.
And after a point in time I was kind of asking myself as to what I am cut out to be in my life am I going to be doing only research for the rest of my life or is there anything else I could do,and that led to some introspection so at that point in time I realized that, you know what's missing in my job then was teaching so I would like to not only discover knowledge throughresearch, but more importantly, disseminate knowledge that we have created by teaching and engaging students by doing so.
[1:50] We co-create solutions to problems. So then I thought, well, maybe I should switch my career, you know, do both teaching and research.
Then I bumped into a magazine, Science Magazine, and that was back in 1995, precisely in October.
And then I saw this interesting advertisement from UNIVERS.
[2:12] You know, they said, well, they're looking for a new faculty member to initiate research in air quality, which never existed before in Singapore.
And they also created a new department called Civil and Chemical Environmental Engineering with a new concept.
And I thought, wow, you know, it looks very interesting. So why don't I give it a shot?
And then I spoke to my wife. I said, well, let's give it a try.
And I'd never been to Singapore, actually. So we had kind of a crazy idea.
Then I said to my wife, let's go, you know, And then give it a try for three years.
If things work out, perhaps we can stay on. If things don't work out, head back to the U.S.
And I came here, one thing led to another. I've been here for 28 years.
And so I had a lot of interesting opportunities along the way to do research and develop a curriculum for a number of courses and also do collaboration with students from variousbackgrounds coming from various countries.
In addition I also did a collaboration with fellow faculty members coming from other universities in Europe and North America and so on see that's been very much fun no complaints,probably the only complaint I would have is like I probably need more than 24 hours a day.
Balancing Time and Responsibilities
[3:31] So it's a question of managing the time effectively so that you get to do everything that you want not only as a faculty member but also as a member of the family yeah.
Collecting Cloud Droplets for Research
Brent:
[3:42] Definitely yeah it's a struggle a lot of people can relate to, And you talked about having a lot of fun here. I want to go back to a story that we mentioned before we recorded todayabout your time collecting rain or cloud droplets for acid rain research.
Rajasekhar:
[4:01] Yeah.
Brent:
[4:02] Can we hear that story?
Rajasekhar:
[4:03] Sure, yeah. You know, when I did my PhD back in Miami, Rose Institute School, I was doing research in the lab in a very much controlled environment.
And the project I was working on was very intriguing.
And we were talking about meteoric ablation, you know, how it sort of affects the chemistry of the atmosphere and so on.
So afterwards, I thought I should do something more relevant to what the world is looking for.
And then I joined Albany, Wadsworth Center, Albany.
And they had a very interesting project.
And so that got my attention. And so basically, they were trying to solve a mystery.
And the mystery then was like in Adirondacks region, and there was a massive fish kill in several lakes, including Lake Placid, where the Winter Olympics was held years ago.
And they were curious to know what really was going on that led to massive fish kill in lakes, given the fact that we don't have any industries within a perimeter of 200 kilometers in theAdirondacks region.
Whiteface Mountain is what I'm talking about. So then I was involved in that project, trying to figure out what is going on, where the pollution is coming from, and what kind of pollutionis coming from, and how we could tackle it.
[5:29] So, hypothesis then was like, you know, we have the province of Ontario in Canada, which is not too far from Adirondacks, and they take a lot of smelters over there.
And the smelting operation involving the use of fossil fuels, particularly coal, would lead to the emission of sulfur dioxide.
[5:50] Which is an important acidic gas, which could eventually lead to acidification of rain.
And then having said that there was i asked this question you know what about other possible sources especially the ohio river valley and very a lot of industrial activities as you guysknow and at that point in time they were still using coal of course a better quality but still intensive uh industrial operation was going on and then if you look at the the wind patterns yougot a jet streams coming from the west to the east so certainly whatever emissions you have from power plants, from industries would be carried forward by prevailing winds going pastthe Whiteface Mountain and then, you know, then you could lead to some kind of acid rain.
Unraveling the Chemistry of Acid Rain
[6:35] So what I wanted to do was to unravel the chemistry of acid rain over there and the precursor before the acidification occurs is some in-situ chemistry within cloud droplets.
So if we just imagine each cloud droplet is more like a micro-reactor And that will process some interesting chemistry, which is very hard to study.
And then, so the hypothesis I made was like, you know, we are kind of bringing sulfur dioxide, perhaps from the Ohio River Valley, but we are not disregarding what could potentiallycome from Ontario.
[7:12] At the same time, we are producing a secondary pollutant like hydrogen peroxide, which is an important oxidant that is used for coloring the hair and so on and so forth.
So that oxidant hydrogen peroxide would probably convert sulfur dioxide into sulfuric acid.
And then when the cloud droplets are transferred to rain droplets.
[7:36] Collision, and then it will lead to acidic rainfall, and that could basically leach out some metals from soil, and the toxic metals that are leached out could eventually find themselvesin reservoirs that fish are exposed to, and hence the fish kill might happen.
But that is a hypothesis. I had to prove it. And then what is so special about the Whiteface Mountain or Hadar and X is that we have the so-called orographic clouds.
I don't want to go into details, but it's a type of special clouds that are formed on top of the mountain under certain weather conditions, especially during the nighttime.
And then you have the sulfur dioxide getting into clouds.
You have the hydrogen peroxide sitting out there, which is soluble in water, which will also get into cloud droplets much more readily than sulfur dioxide.
Dioxide, then the in-situ chemistry would take place converting sulfur dioxide into sulfuric acid.
So I wanted to prove that. So what I did was to... The clouds are formed during wee hours of the day, like two o'clock, three o'clock in the morning.
[8:42] So then I sort of stayed in a hotel at the basement of Whiteface Mountain, and then I I had to look out every night to see if we could see the, kind of, if we could find the light of theobservatory on top of the mountain.
If we could find the illumination, we are okay, no case.
But if we cannot find the illumination, that's an indication that we have some blanket of clouds hovering around the mountain.
Then immediately I would drive up and then, you know, put the jacket up when I have a passive cloud collector.
[9:18] It'll collapse the all cloud droplets and then it'll sort of trickle down to the bottom and then collect it and then inject it into some instruments and figure out what's going on.
So that was kind of interesting. But then if you really want to study the chemistry, you had to go at two o'clock in the morning taking the risk.
So I was in my early 30s and I was very audacious and didn't worry about the consequences of driving up all by myself, going through the tunnel and then putting the passive collector upthere and so on.
And then I actually studied 23 events over there in July and August.
So, that was unprecedented and none of the researchers did before, although they made a lot of attempts.
So, and then we published papers and then we solved the mystery.
So, basically what we said was like, the pollution is coming from the Ohio River Valley predominantly, but what's coming from Ontario is relatively smaller.
[10:11] And then we have this interesting chemistry taking place and so on.
And so the way to solve the problem is to regulate the emission of sulfur dioxide much more tightly so the problem could be solved.
It happened. The question then is like, did we solve the problem? Unfortunately, not.
And there was another mystery. What really happened? There was a question.
So the answer that we could come up with is that, well, over the years, because of persistent persistent acidic rainfall on soils whatever the buffering capacity that soil had has beencompromised we don't have any more basis buffers that could neutralize the acidity coming from the rainfall it's all leached out so the soil becomes very sensitive the water becomes muchmore sensitive as a result and the fish kills still occur so the lesson we have learned out of this is serious like pollution prevention is far better than pollution control.
And much more importantly, the environment is not as resilient as you think it will be. So, yeah.
Keller:
[11:16] Had you had the opportunity to do field work like that while you were doing your PhD? Or was that the first time?
Rajasekhar:
[11:21] Not at all. That's why I was so excited. So what I was doing with my PhD was like a controlled environment, like a reactor and so on.
So then I challenged myself, we want to be a successful researcher, or faculty, I could come out of a comfort zone and do something innovative, creative, so that I can define problemswith a broader perspective.
That's why I joined Watsworth Center. And then the project was really interesting.
I'd never done anything like that before.
So I had to teach myself how to go about collecting cloud droplets using a passive sampler, which I designed.
And one thing led to another. It was a huge success and so on.
So then the question is like, when he moved to Singapore—.
[12:07] We cannot collect cloud droplets. We don't have mountains. You know, the clouds over here are beyond our reach.
Adapting Research Methods in Singapore
[12:13] So what else can you do?
Then, of course, then I thought, well, forget about clouds. You know, just collect rainwater, as simple as that.
Then I started collecting rainwater. I had a shock.
I looked at the pH of rain, and I thought it's going to be close to 7, neutral, which is okay.
It was like 4.2. Oh, my God, what's going on? pH is 4.2, so acidic, right?
And then I saw another mystery, and we published a paper back in 97, 98.
And interestingly, during that time, we had a so-called smoke haze hovering around the entire Southeast Asia region because of what happened in Indonesia in 97, 98.
So, we had massive uncontrolled forest and peat fires over a very large area.
[13:08] Then you have all kinds of pollutants that are being emitted.
Then they're transported across Singapore.
Despite having clouds, there was not much rainfall.
That was an interesting phenomenon that we observed.
Anyway, then we provided an explanation as to why rainfall was suppressed.
Because of soot particles coming from forest fires which absorb the sunlight, will heat up the atmosphere, and the cloud droplets will evaporate.
Brent:
[13:40] Interesting.
Rajasekhar:
[13:40] Or with very little, you know, water content. So they don't collide so much.
Even if they collide, there's no sedimentation. There's no rainfall, right?
But whenever the rainfall occurs, we collect other rainwater.
And so then we explain what is really going on. Anyway.
Brent:
[14:00] That's definitely super interesting. And isn't it true that Singapore still has a lot of issues with Indonesian night fires during...
Rajasekhar:
[14:30] The U.S. So the peat over here is enriched with a lot of sulfur. It's much older.
And then, so as the plants, they start, the biomass starts decaying, then, of course, we lead to the formation of peat before qualification occurs, you know, the fossil fuels. So this is likeintermediate stage.
Then you have massive peat lands over here. There's a lot of vegetation.
And so when you have these wildfires, You have a combination of both forests and peat fires, emitting a whole bunch of pollutants which are very unique over here.
So I studied this problem not only in Singapore, but also in Kalimantan, in Sumatra, in Indonesia.
So I was able to do the source-sink mapping, where the pollution actually originates from, where it arises from, and where it eventually will end up.
That we can connect the sync with the source and figure out the trajectory.
Brent:
[15:33] Are there chemical identifiers for different type of pollutants?
Absolutely. Okay. So if you collect rainwater here, you can be, oh, this came from. Yes.
The Impact of Indoor Air Pollution
Rajasekhar:
[15:41] Okay. Yeah. So it's more like what I call environmental forensics.
Brent:
[15:45] Yeah.
Rajasekhar:
[15:46] That's a kind of interesting field. So you had to find the chemical fingerprints.
And that was my first goal when I took up the project.
I did manage to find chemical fingerprints, as you rightly pointed out, which are pretty much unique or specific to the region, which you don't find elsewhere.
So, although wildfires are happening widely across the world, the kind of impacts that wildfires have over here will be very different as compared to what's happening elsewhere.
Brent:
[16:14] Yeah. And then for those who don't know, could you define what peat is or what it's used for?
Rajasekhar:
[16:18] Okay. Peat, you know, we have a lot of peatlands, especially in Indonesia, and that's below the ground.
You know, it could be a few hundred meters below ground. and so the what's unique about the peat is that it'll continue to smolder for ages unlike the above-surface combustion withvegetation that's more like a flaming combustion you know but over here this like smoldering so it keeps moldering for almost forever it's very hard to put out so it's such fire At the sametime, the peat we have here, it has a lot of carbon in it, especially organic carbon, which is nothing but biomass, right?
So, you have carbon, hydrogen, oxygen, and so on.
In addition to that, you also have sulfur in peat. There is something unique about the peatlands in Indonesia.
[17:16] Then we also have coal fields, again over here, especially in Indonesia.
So, because of excessive logging of trees or deforestation, especially during the drought, persistent drought periods, then you have a combination of peatland fires, vegetation fires, as wellas cornfields.
Surface coal will also be ignited on a hot, sunny day. Then you have a combination of all these fires taking together.
So that makes the source identification very challenging.
So we managed to do that using a chemical mass balance model and some field experiments as well.
Brent:
[18:02] Okay. Yeah. Yeah. And then is peat just like decaying wood?
Rajasekhar:
[18:07] Wood? Yeah. Yeah. Yeah. Kind of. Yeah. Yeah, but that wood is different from the wood you find above vegetation, above surface.
So, if we look at the stem of trees, again, it's wood, right?
So, the composition of wood is very different from the composition of wood you find below surface.
So, basically, if you look at it in terms of chemistry, you have something called lignin, and then you have cellulose, and you have hemicellulose.
So, any wood would contain different proportions of cellulose, hemicellulose, and lignin.
And what contributes to the rigidity of tree roots or trees, especially the stem of trees, will be lignin.
So, the lignin content varies significantly between the vegetation you have above the surface and the one you find below.
Brent:
[18:55] Okay.
Rajasekhar:
[18:56] Meaning the peat, right? And then because you have smoldering fires lasting for almost forever, you have low-level fires, more like fugitive emissions happening for a period oftime.
And then that will ignite vegetation fires over the surface.
Brent:
[19:17] Okay.
Rajasekhar:
[19:18] So the key thing to find out is how to put out.
Below-suffice peatland fires. That has been the real challenge.
Brent:
[19:28] Sounds similar to Florida mongroves, where it could travel and pop up in different spots.
Rajasekhar:
[19:33] Correct, correct. So it could try to remain ignited almost forever below the ground.
And then you have emissions of particles in particular. We are talking about ultrafine particles, extremely small in size.
Especially fire extinguishing, the ones who put out fires, they're exposed to such emissions of particles which happen to be much more toxic than what you would get from typicalindustries because you have incomplete combustion.
So when you have incomplete combustion, smoldering is an example, the kind of particles you would have will have very different chemical composition as compared to nearly completecombustion you would have in a power plant with high combustion efficiency efficiency, and so on.
Brent:
[20:23] Interesting.
Understanding the Complexity of Air Pollution
Keller:
[20:25] And then we've talked about a couple, I guess, rural examples of air pollution.
I was wondering if you could give people a general framework of how they should think about air pollution in urban environments as something that generally, unless it's extremely hazy,you're not going to see.
Rajasekhar:
[20:39] Yeah. Well, air pollution is a very complex, multifaceted environmental problem.
Because of historical reasons, it has been ignored.
For ages, people don't realize that exposure to air pollution will turn out to be extremely detrimental to human health.
So, what has been documented in literature which cannot be debated is that air pollution is an invisible killer.
And in fact, in the absence of COVID-19, every year we are losing about 7.5 million.
[21:20] Due to premature deaths. So the premature deaths do happen every year to the extent that we lose about 7.5 million people because of exposure to air pollution, both indoors andoutdoors, in developing and developed countries.
So this is like premature death, mortality. But on top of that, we also have morbidity happening.
For example, asthma, bronchitis, decreased lung function, lung cancer.
So you have all these problems that exist, but people don't even realize it.
And they might think that it's because of diet, you know, they have other lifestyle they adopt or whatever.
But it could be the result of exposure to air pollution over a long period of time. I call it chronic exposure.
So acute exposure and chronic exposure together to air pollution could affect the quality of human life.
To the extent that people might die prematurely or develop diseases that will make them less functional than usual.
Keller:
[22:27] Do you have the numbers on what proportion of people that are affected by this die of the 7.2 million?
What proportions indoor versus outdoor?
Rajasekhar:
[22:37] Yeah, I think the indoor exposure to indoor air pollution is probably a little higher than outdoor air pollution. And that mainly happens in developing countries.
So the problem is that we have the affluent proportion of the human population, the top 1 billion people.
Then we have the bottom 2 billion people who happen to be extremely poor.
[23:03] And they live in developing countries with inadequate access to cookstuffs, clean cookstuffs.
So they had to make a living and they had to carry on their life.
And so what they try to do is to make use of dead wood for cooking indoors or cow dung or stuff like that, the kind of biomass they have for cooking activities.
And they happen to live in ill-ventilated homes, burning dead wood in less than ideal conditions.
So it's more like peat fires. So, you have a lot of smoldering combustion because the wood is not easily ignitable, especially dead wood.
And they try to burn it very hard and they're being exposed to that kind of pollution.
So, we lose a significant proportion of people because of exposure to cooking indoors in developing countries because of not having access to clean cook stoves.
But apart from that, even in developed countries, you seldom realize, but even domestic cooking.
[24:17] Cause issues, including lung cancer, for example.
And the reason is that now there's an article published in the New York Times talking about emission of particles and gaseous pollutants from gas stoves, which are the electric stoves. Itmakes a big difference.
[24:38] So the case of gas stoves, because you have a natural gas methane with some amount of propane being used over there, and you have emission of carbon monoxide, much moreimportantly, nitrogen dioxide.
It's a, you know, deadly pollutant. And so, people do cooking in a smaller apartment, you know, that's not well ventilated, and they're exposed to gaseous pollutants and particles thathappen to be smaller in size.
But on top of that, what do you cook? how much you cook, and how you cook, and how long you cook, could also make a difference.
So, like, for example, in Asian countries, deep frying is the one common method of cooking, right?
People enjoy and cook, you know, pre-cooked food, especially not the baked items, but deep fried food, right?
And you use oil as a medium for cooking, right?
So, on top of what's coming out from gas stoves, you have oil being burnt, and you add ingredients, you know, kind of masala or whatever you call it, you know, spicy stuff that adds tothe flavor, to the taste.
And then you do cooking like meat, it has its own cholesterol that comes off, right?
So, you have a whole bunch of stuff coming out to do cooking activities indoors.
[26:00] And people seldom realize. And then they may not have a kind of a local exhaust.
So you have to have a local exhaust that's going to suck away your cooking fumes and dispose it in the outdoor environment.
If you don't have it, you have direct exposure to cooking.
Indoor Air Quality and Pollutants
[26:18] But even if you do have it, it may not be very effective unless cooking fumes are well dispersed, which would happen in a very ventilated kitchen. kitchen.
And so, people have to keep the doors, windows open, and then the cookstores have to be positioned in a particular location that will make dispersion of fumes more favorable thanotherwise.
So, all these factors are seldom considered, okay? So, again, that causes problem.
In addition to that, because of religious practices, people burn incense sticks, which you would have noticed over here.
Brent:
[26:54] Right?
Rajasekhar:
[26:55] And so it's more like aromatherapy or whatever you call it. And people don't realize that you are emitting a lot of pollutants due to incense burning.
It smells good. What smells good is not good for our health. You know what I mean?
Brent:
[27:08] Would you say that's generally true? Yeah. What smells good is not good for our health?
Rajasekhar:
[27:11] Yeah, yeah, yeah. You know, like fragrance.
Brent:
[27:13] Right?
Rajasekhar:
[27:13] You know, even perfume.
Brent:
[27:15] What about like essential oils?
Rajasekhar:
[27:17] Yes, everything, everything. It's all organics. We're organics, right? So all these organics that we are exposed to could turn out to be very harmful in the long run.
In fact, there's an interesting subject coming up called home chemistry.
Brent:
[27:33] Okay.
Rajasekhar:
[27:33] Yeah. So that's becoming like a discipline on its own. And especially in UC Denver, they do this kind of research. Also in Boulder, Colorado.
So it's a specific academic group that does a lot of research on home chemistry.
Trying to find out what kind of pollutants that we are typically emitting indoors as a result of whatever activities that we get involved with on a day-to-day basis.
And then how is it different compared to outdoor pollutants.
Brent:
[28:02] Yeah. Because I know there are huge problems like cleaning products, like detergents and all those, right?
Rajasekhar:
[28:06] Absolutely. Even vacuum cleaning, right?
Brent:
[28:09] Oh, like an exhaust?
Rajasekhar:
[28:10] It will resuspend particles, like especially when you have carpets.
So when you have carpets, you know, you have a lot of dust particles deposited, then you have to suck them out, you know, with a very high-powered vacuum cleaner.
So in the process, some of the particles deposited onto the carpet, onto the floor, will be resuspended.
And if you don't wear a mask, you don't realize that you are exposed to dust particles.
That's when people start sneezing, develop some allergy, you know, some symptoms and so on. And again, it's not good.
And you can go on and on. There are various other sources, like candle burning.
Brent:
[28:49] Yep.
Rajasekhar:
[28:50] Again, could be another source of pollutants. And photocopiers, you know, could be another source of product.
I don't use my photocopier or printers, right? They all have carbon block.
Keller:
[29:00] Yeah.
Rajasekhar:
[29:00] Right? And so, we have a whole bunch of pollutants coming from indoors.
And don't forget the furnitures we have.
And as a result, a natural wear and tear, something called formaldehyde, that comes off from furniture, right? Right.
So we become our own enemies in a way.
Mitigating Indoor Air Pollution Exposure
Brent:
[29:20] Are there like general practices you take or do, or you suggest that people do to like mitigate some of these exposures, especially in like more urban centers?
Because it's probably a lot harder to go to developing countries and tell them how to fix their cooking situation.
Yeah. What are some basic things that people should do?
Rajasekhar:
[29:38] That's a very good question. Indeed. Indeed, most of the time, you know, our approach to tackle pollution in general, and particularly air pollution, has been reactive.
So we wait for a problem to happen. We realize the impact and the consequences of exposure to that kind of pollution.
Then we come up with a policy. We take actions. But then it's rather too late, like what I explained about what happened in Whiteface Mountain.
So like I said over here, there's something called sick building syndrome.
Especially in indoors, right? So we don't have regulations when it comes to indoor air quality like the way we do for outdoor air quality.
So this is one of the pitfalls of improving air quality.
So quite often people think that when you remain indoors, you are reasonably protected, against exposure to air pollution, which is not the case.
And so when we have large members of people, building occupants, complain that they have particular symptoms like headaches or, you know, eye irritation, throat irritation, some kindof fever or whatever, then those complaints are taken seriously.
That's the time we do the investigation by comparing the concentration penetration of measured pollutants against indoor air quality guidelines.
We don't have standards, but we have guidelines.
[31:05] And then if what you measure exceeds guidelines, that's an indication that the indoor air quality is inferior, is not acceptable.
Then we try to take actions, you know, try to improve ventilation, try to remove the sources of pollution, and so on.
That is not the right approach. So we have to do the inspection of buildings quite frequently just to figure out whether or not we are okay, right? So that has to be there.
And thanks to recent developments in sensing technology.
So now these days, you have pretty cheap sensors being available.
You can purchase like a sensor for about $5 or $10, right? It may not provide very accurate data, but it will give an indication whether or not we have pollution, air pollution, at a givenlocation, at a given time.
So, this is something we can afford. You know, we can actually use it to safeguard our health. This is what I would suggest.
And then if we realize that we do have pollution problems of concern, especially from the public health viewpoint, what can we do?
Well, we cannot do the retrofitting of an existing apartment or house and so on. It's going to be expensive.
And you may not like to have centralized air conditioning systems, which is a good idea, but it's very energy intensive.
So, we shift pollution burden from indoors to power plants.
[32:31] Which is not good either. So what I would suggest is like, we could have some portable air cleaners or air purifiers, which are pretty cheap.
You can get something for $200 or whatever and so on.
So when you realize that you are being exposed to a particular type of air pollution because of what's happening indoors, then we want to position our air cleaner in a location that's not toofar from where you are.
But make sure that the windows or doors are closed.
So if you have a tiny little air cleaner it is not designed to clean up a massive volume of air, that would remain indoors and what being brought up brought in from outdoors as well right sowe had to keep the windows doors closed and then turn the air conditioning and air purifier on, that'll clean up the air then you have better air quality which you can check with a portablecheap sensor have.
Brent:
[33:26] You ever looked at using plants as an air filter there.
The Benefits of Phytoremediation
Rajasekhar:
[33:28] Yeah yeah i mean uh so plants are good you know uh because they do what you call phytoremediation and so so plants tend to absorb and certain pollutants and so on but again uhthere are some limitations uh because for plants to continue to grow uh they have to absorb carbon dioxide you know so they can do photosynthesis and if you look at the plant physiologyetiology, each leaf will have a lot of stomata, you know, tiny little pores, through which they uptake carbon dioxide and release oxygen.
Now, imagine if we have a lot of particles indoors that the plants are exposed to, and the stomata, the tiny little pores that you have on plant leaves will be blocked.
It's like artery being blocked for humans, like a hot attack.
So, likewise, the plants cannot survive.
Brent:
[34:22] Yeah.
Rajasekhar:
[34:23] Without doing photosynthesis. And you can look at the discoloration of leaves and so on.
So my answer to your question is like, you know, having plants will add to ornamental value, aesthetic value that you have indoors.
To some extent, you can do decontamination, but that cannot be the ultimate solution.
Brent:
[34:45] Definitely.
COVID-19 Impact on Air Pollution
Keller:
[34:47] One of the papers we looked at was looking at the impacts of COVID-19 on air pollution. Could you explain how the reduction of economic activity impacted pollution? Yeah.
Rajasekhar:
[34:57] So that was a natural experiment we did. And so because of COVID-19, a lot of economically related activities were halted.
[35:08] Not intentionally, but we got no choice but to do that in order to safeguard human health by protecting movement restriction, by imposing movement restrictions, mobilityrestrictions.
So, at that point in time, of course, there was a significant reduction, particularly the amount of carbon dioxide being emitted, well-known greenhouse gas.
It's not the only greenhouse gas, but the major contributor to global warming.
So, we had about 30 to 40% reduction in the emission of carbon dioxide during COVID-19, especially when lockdowns were implemented.
In Singapore, we call it circuit breaker. record.
So, apart from that, you also had reduction in the emission of air pollutants, not greenhouse gases.
For example, primary pollutants like carbon monoxide, sulfur dioxide, and a whole bunch of pollutants were also reduced in concentration during that time.
So, in general, there was an improvement in air quality, and there was improvement in terms of mitigating climate change as a result of reduced emissions of all pollutants, includinggreenhouse gases.
But that effort could not be sustained for too long, because we are talking about life versus livelihood.
[36:32] There's always a competition between the two. And so COVID-19 disrupted our life, disrupted our economy.
[36:41] And so after the lockdown was was lifted.
Then suddenly we have to restore our economic activities to feed the population, local population, and to create jobs or at least let them have their jobs.
So then pollution was back to normal.
[36:59] So what we succeeded in terms of improving air quality could not be sustained for long period of time.
Because of our preference to boost our economy. So the lesson we have learned out of this is like, can we switch to green economy?
So the conventional economy as such is already known to be harmful to our health, and suddenly it deteriorates the quality of our life.
But at the same time, we have to boost our economy. So, can we do something like environmentally conscious manufacturing of products that are still in demand in the consumer market?
So, that requires a paradigm shift in our commitment to boost our economy.
It's happening globally, but it's not happening as much as needed.
Brent:
[37:56] And then, would that just look like cleaner energy sources?
Rajasekhar:
[37:59] Certainly, certainly. Totally. I mean, so, you know, if you switch to renewable, cleaner energy sources, you not only reduce the emission of greenhouse gases, but you also reducethe emission of air pollutants that are well-known, including particles.
So we tend to live longer and stay healthier if we manage to do that, right?
But we are still waiting for the right opportunity to switch to renewable energy because of a variety of reasons.
Either the technologies are not very mature or the technologies that are being utilized to generate renewable energy are not cost-effective or they are intermittent and therefore we have tostore energy using energy storage devices which are not readily available available or we have to have a spot grid that will basically connect our conventional energy sources withrenewable energy sources mix and match as and when needed so that our demand is met with the supply of renewable energy to a larger extent than conventional fossil fuel generatedenergy.
Engaging Policymakers for Change
Keller:
[39:15] And were there any policy implications that you were able to make after that research paper on COVID-19 on the tendency that we should be trying to go towards a greeneconomy?
Rajasekhar:
[39:23] Absolutely. So, I mean, knowledge discovery is very important, especially fundamental knowledge that we create will provide a strong foundation for us to explore potentialtechnological solutions.
So, then once you explore and then demonstrate the effectiveness of solving problems with implementation of technological solutions, we have to translate our research outcomes intopractical applications.
So, in the process, policy development plays an important role, a vital role in solving problems.
So, then the question is like, how do you engage policymakers?
Policymakers how do you really convince them that whatever technological solutions that we propose will turn out to be very good in solving a particular problem of concern sopolicymakers are not so much interested in getting to know all the nitty-gritty details of your research or the scientific outcomes what about online so if we don't do it what's going tohappen to us If we do it, what are the cost implications?
[40:32] So we had to reach out to policymakers using a different language as compared to what we typically use to engage the research community globally.
So that requires a lot of details, right? But when it comes to policy, talking to policymakers or having a conversation with the policymakers, we got to simplify the language, okay?
In no uncertain terms, define the problem, illustrate the effectiveness of solutions that you have discovered, and more importantly, tell them as to what differences could make to economyand public health and overall lifespan of people.
[41:13] So that's something I have done. And in fact, I've been interacting with UNEP, United Nations Environment Program.
And so I have done some policy-relevant work as well as a member of the research community representing Singapore in a different capacity.
And so I just basically published a couple of policy-relevant papers.
And if you look at it, very, very simple language that anybody can understand.
So simplification of scientific facts to the extent that anybody can understand is a way to engage policymakers do.
Brent:
[41:50] You think scientific illiteracy is like the biggest like hurdle for policy changes or do you think there's like other issues like corporations influencing politicians or other agendasgoing on that are yeah so.
Rajasekhar:
[42:05] I mean the And the way it goes is like, you know, we have competing goals to accomplish.
We all know that we need a clean environment and green environment.
There's no dispute over that. But in developing countries or even in developed countries, priorities could vary.
So are we going to create more jobs to keep people happy?
Or are we going to reduce jobs and focus more on the environment?
Or not necessarily reduce the number of jobs we have but change the focus of what we are doing right so that requires a strong political will and that, disrupt ongoing business operations.So the business community might also raise some objection to what we are planning to do, like green economy, for example.
Overcoming Challenges for Green Economy
[42:55] But then we have to engage social scientists, especially behavioral scientists, who could make a huge difference in engaging the global community, including policymakers, makersand tell them that we have a job, you know, we have a problem at hand that needs to be resolved sooner than later.
And if you wait for too long, it's rather very late, you know, but then the consequences of actions not having been taken will be serious.
[43:32] So, that requires collaboration. In fact, I do that. So, in fact, I submitted a recent proposal to the local government, and I have a sociologist as part of the team.
And the sociologist looks at the same issue from a very different perspective.
And then, so I make my own discovery in the scientific manner.
Then I share the findings with the sociologist, and the sociologist will carry forward the scientific message in a non-scientific manner to reach out to the community.
At large, including policymakers, and tell them that this is a way to go ahead, and improve the quality of the, the environment or the quality of air we breathe.
Brent:
[44:19] Yeah no that's great and then one other thing, have are you aware of any research looking at economic downturns and like deaths or like illnesses that occur because people can'tafford health care and like the implications of, that end of things of where if we let our economy like slide what's the health and like Like death outcomes from that versus, okay, if we goto a greener economy, how many lives and health outcomes are we saving that way?
Rajasekhar:
[44:54] Yeah. There's something called techno-economic analysis, right?
Which is something very important for any research project to do.
So my own perspective based on the years of experience I have, publishing papers is very good.
But what's more important is to come up with a techno-economic analysis and then figure out what kind of social benefits we could derive in the long term as a result of investment inR&D.
So, we are looking for ROI, returns on the investment, right?
So, when you have benefits, social benefits, economic benefits, health benefits exceeding the investment you make, that's terrific.
Then there's no question at all in the policymaking viewpoint.
Oh yeah, we will go ahead. We'll do it, right? But then how do you really do this calculation that requires a lot of effort?
[45:45] That's one thing we do. On top of that, there's something called Life Cycle Assessment, LCA, which is a very important policymaking tool, seldom considered in research, but it'sbecoming vital over there.
So then, especially when they talk about climate change and CO2 emissions, there are different modes of doing carbon footprint analysis.
We call it scope one, scope two, scope three.
So, scope one, scope two are rather straightforward, direct emissions or economy-related kind of emissions.
But scope three is much more complex because that requires the analysis of carbon footprints over a larger supply chain network.
To give an example, like EVs, electric vehicles, are becoming very popular and the price may even go down.
But what we need will be lithium-ion batteries.
[46:42] It's actually chargeable, of course, chargeable. Then the question is like, where do the lithium ion batteries come from?
Only a select number of countries have access to lithium.
Bolivia, Australia, China, you name it. Probably only about eight countries have access to lithium.
And then if you look at the way lithium ion batteries are made, they're made in some countries, they're transported across the border through shipping. and then in all these stages, we areemitting carbon.
Not only in terms of extraction of lithium, refining of lithium, but manufacturing lithium-ion batteries, the transportation of lithium-ion batteries, more importantly, when the lifetime isover, after 10 years, what do you do with the lithium-ion batteries?
Do you discard them as unwanted product? Or can we switch to something else that can extract, we can extract lithium out of it?
That's a project we are kind of working on. We are just publishing a review paper.
And that basically brings together all the important concepts related to life cycle assessment.
That will be very insightful. So, when you do this life cycle assessment, then you would realize that just continuing to purchase lithium-ion batteries, despite being relatively low price,may not be very good in the long run in the context of particularly climate change.
You can purchase it in the beginning, but later on, you do recycling.
[48:09] Locally so you still have access to resources that you don't have originally right so that's the kind of resource recovery so if you can recover resources out of what is called wasteshortage that makes you self-sufficient okay so the way to go about defining waste is like it's nothing but a resource that's out of place that's right no waste at all zero waste right Right?
So that's the kind of direction we want to go.
And this is the kind of other project I'm involved with.
And so, yeah, that's my answer to the question. So we need techno-economic analysis.
You do a life cycle assessment together.
With all these tools we are using, apart from knowledge discovery, you do, you can come up with a strong policy-oriented message that we can share with the entire community with theno-care situation, and we will succeed in our effort in solving problems of environmental concern.
Keller:
[49:09] That's amazing. It sounds a lot like the cradle-to-cradle kind of philosophy.
Rajasekhar:
[49:12] Yeah. We go from the cradle to grave, or from wheel to wheels.
So it's a kind of way to go. You want to close the loop.
Keller:
[49:24] There's a lot we can go into on there, but I think we want to pivot a little bit to the work you've done on biomass.
Yeah. So could you tell us a little bit about, first, what is biomass waste and how we can use it as a source of resource?
Rajasekhar:
[49:35] Oh, yeah, yeah. I mean, biomass is nothing but the kind of thing you find in vegetation, right? So vegetation contains biomass.
[49:49] That's what—basically, it's nothing but vegetation, right? including in the stem of trees, tree roots, leaves.
Everything's made of biomass, which has been made out of photosynthesis.
So basically, your plants, for their own survival to be self-sufficient, they absorb carbon dioxide together with the water vapor that they process in the process of sunlight and convertingcarbon and hydrogen into complex organic molecules.
That'll be biomass. biomass so having said that it's more like a polymer okay and then the kind of polymer that you have in the form of biomass would differ from one plant to another theage of plants and whether whether the woody or non-woody plants and so on so then we have all kinds of biomass and then the good thing about biomass is that it absorbs carbon dioxideso that's one way you know to fix climate climate change problem by seeking nature-based solutions.
So if you do reforestation, if you do afforestation, you increase biodiversity, which will eventually lead to more uptake of carbon dioxide and so on.
But the vegetation plants would not continue to uptake CO2 with the same magnitude forever.
[51:13] Once the trees become more mature, the amount of CO2 they absorb will be relatively lower, right?
And then you also have natural, you know, falling out of trees because of various reasons, including weather conditions and so on.
So then they become dead biomass, right? So what do you do with the dead biomass?
In the past, we used to burn it in an incinerator as an unwanted product.
Then you throw out more carbon dioxide. He also throw a lot of valuable resources that he have.
So what we try to do is to convert.
[51:50] Waste to biomass into resources. We go from trash to treasure, if you call it, right?
So that's the kind of research we have been working on as well.
And that is kind of related to open biomass burning, which would eventually lead to wildfires.
So we want to educate farmers. We want to educate the agricultural community.
There's a better way of dealing with waste to biomass.
Don't go for open burning. If you go for open burning, it becomes like a wildfire.
You cannot put out such fires.
Environmentally harmful and very detrimental to human health.
So then you sort of burn it in a confined environment using pyrolysis or hydrothermal treatment.
There are technologies being available now which are reliable, not very expensive, and you can convert into a variety of products that you get.
And that is going to be the future. You know, you can even make chemicals, you can make fuels, and you you can make a lot of other useful products out of waste to biomass.
And so that's, we call biorefinery. So rather than chemical refinery, it can come with the biorefinery.
And that will solve many problems. But at the same time, you also close the carbon loop.
So you are not emitting any more carbon than you already had.
So in that sense, it's also very good.
Converting Biomass Waste to Resources
[53:15] So that's the kind of project we have been working on as well.
And we've managed to make a lot of useful products.
So that could be sold to commercial organizations.
Of course, we had to scale up the process. So what we had done is more like a pilot scale experiments, which turned out to be successful.
But we need more funding to demonstrate potential application of a large scale process.
And so this is a work in progress.
Brent:
[53:46] That's great. And it also seems like another stream of income for these farmers, because they can sell the actual agricultural product. Correct, correct.
Rajasekhar:
[53:53] Yeah, in fact, you know, you can make something like a formic acid, you know, which is one of the important chemicals, and farmers can also make what they call charcoal,activated carbon, and that could be used for decontamination of water, that could be used even for absorbing carbon dioxide in plants and so on.
So, farmers could make more money, like you pointed out, using a cheap technology that's affordable, accessible, and deployable and replicable.
Brent:
[54:24] Yeah. And then would food waste be similar to the agricultural waste?
Rajasekhar:
[54:28] Absolutely. Absolutely. So, now if we just track the amount of recycling we do with food waste, it's less than desirable, less than 10% in many countries.
But then if you look at the composition of food waste, right, it has the combination of proteins, it has a combination of carbohydrates and lipids, right?
And then how do you really separate these two components? If we can separate these two components, like carbohydrates, it can make methanol.
[54:54] From lipids, you can make other chemicals, right? So how do you really segregate different components you have in the food waste that requires an enzymatic process?
And so food waste can be converted into a whole bunch of products.
You can also make fuels out of it. For example, methane, natural gas, right?
So that's a well-known technology called anaerobic digestion.
So, if you use certain enzymes, particularly those enzymes could crack the food waste and then make methane out of it.
So, that will turn out to be really a useful application in terms of generating energy.
Just imagine if we can collect food waste in all hawker centers that we have in Singapore, all food courts in other countries and so on, that becomes a source of methane that could use togenerate energy, electricity in the immediate vicinity of food courts.
So then you don't have to have the supply of electricity over a long transmission line, which could even lead to some kind of loss of electricity and so on. It's also combustion.
But instead, we could have decentralized operations.
And then each community could become self-sufficient into being able to generate its own energy out of waste.
So waste to energy is the other way of looking at it from waste food resource. source.
Brent:
[56:23] And then on that, if you were to get methane from the food waste and then burn it and use it for energy, does that release pollutants from burning the methane?
Because I know most people think about methane as being a pollutant.
Rajasekhar:
[56:35] Exactly. So the way to look at it, this is for like energy transition.
So I won't say that this is the panacea for the problems we have in terms of reducing carbon emissions, right?
But then, for example, in Singapore, we are importing methane from other country, right, for now.
And then about 95% of electricity is generated out of methane in Singapore at the moment.
Brent:
[56:58] Wow.
Keller:
[56:58] What's like the general, I guess, national average for that, for methane generation for electricity?
Rajasekhar:
[57:04] Globally.
Keller:
[57:04] Yeah, globally.
Rajasekhar:
[57:05] Very less, much less. So in Singapore, we were using oil about 15 years ago.
[57:11] Also methane, but not so much.
But then we were able to reduce the carbon intensity by about 35%, but deliberately switching to natural gas.
So like I said, this is more like an energy transitional goal, but eventually we want to have 100% renewable energy.
[57:30] But then you want to reduce carbon emissions in stages rather rapidly, if not gradually.
So in that regard, methane plays an important role because that's the cleanest fossil fuel you could think of because only one carbon versus several carbons in coal and oil.
And the calorific value of coal or oil is much lower as compared to calorific value of methane.
And more importantly, if you want to extract methane from oil reserves, then your whole bunch of gases that are floating together, you have to separate methane out of it to refining, andthen you have to transport it.
So it becomes like energy intensive.
And if you look at energy yield, so that is like how much energy you get out of energy input that you consume to generate electricity, it could be significant.
But over here, you get methane free of gas with no other major gas that need to be separated.
If you do selective anaerobic digestion in a very controlled environment with no other pollutants, like plastics or whatever, with food waste, theoretically, it's possible to have DLA 100%.
[58:46] Conversion into methane, or at least 80% conversion into methane.
And then you could use it as such. You don't have to do the refining like the way we do in an oil reserve.
That's energy intensive. So in that regard, we become self-sufficient.
There's no need for us to import methane from another country.
Usually, the way it's being shipped is through liquefaction.
So you take the gas, you liquefy it in a tank, and then you bring it to the country through shipping, and then you vaporize it.
The Energy Potential of Methane
[59:21] So anytime you change the phase of a material from liquid to gas, gas to liquid, they're more dynamically not favorable.
And you consume more energy. But over here with the food waste, you get methane directly.
There's no reason for it to vaporize from a liquid, right? So you reduce the energy intensity, energy intensity, you still get cleanest fossil fuel for the time being until you are able to switchto 100% renewable energy.
Brent:
[59:49] And then when you're talking about food waste, are you talking about what's left over on your plate or are you talking about spoiled goods in the grocery stores and that logisticalchain?
Rajasekhar:
[59:58] Yeah, yeah, right. But then when it comes to collection of food waste, right, in food cores or hawker centers, we have to make sure we don't throw away, you know, the cutlery.
Brent:
[1:00:09] Right?
Rajasekhar:
[1:00:10] So that could interfere with the enzymatic conversion process.
Likewise, you don't want to put too much of salt either. So that requires, you know, some special sorting out, you know, kind of technology, sorting technology.
So there's a way to do it. It's not impossible. And as long as we make a conscious effort, we can certainly put food waste in a specific designated bin, and then we can use it for energygeneration. Yeah.
Keller:
[1:00:43] No, that's a good idea. Because I know for us, back home, composting isn't very popular.
And I think a big part of that is people just don't—there's no incentive to compost when you can just throw it in the trash.
Yeah. Because the compost is just going to sit in the compost.
Right. Like very few people are using it. But if your energy bill could be reduced.
Rajasekhar:
[1:01:00] Yeah.
Keller:
[1:01:00] You can make some money.
Brent:
[1:01:01] I know.
Rajasekhar:
[1:01:02] Exactly. Yeah.
Keller:
[1:01:03] Yeah.
Rajasekhar:
[1:01:04] So the technology is very well established and probably you had to do some fine tuning.
Other than that, it's okay. Not a big deal.
Utilizing Activated Charcoal for Purification
Keller:
[1:01:13] And then you mentioned earlier the use of activated charcoal to help purify water.
Yeah. As we wrap up, we'll try to transition to some more broad topics, but could you talk quickly about any of the absorption technologies that are coming out in your work there?
Innovative Absorption Technologies
Rajasekhar:
[1:01:26] Yeah. I mean, in fact, we made graphene out of waste to biomass.
So graphene is usually made from coal or from other materials, which is, again, an energy-intensive process. But then we managed to convert waste to biomass into graphene or graphene-like material, having similar properties.
And that has got a lot of useful applications. In fact, we were able to come up with some electronic electrical materials, including fuel cells, out of graphene-like material we made out ofwaste to biomass.
It's performing very well. Well, at the same time, we can also make some graphene aerogels, okay, which can float around in water.
For example, if you have any oil spill, right, and then if you have this kind of foam-like material, right, and you just deploy it in water bodies, it will basically chew up oil, you know, fromthat, very selectively from water medium.
So that way, it can purify water when there is an oil spill by using inexpensive technology over here, which does not require power. It's affordable.
It can sort of disperse it in water medium.
Keller:
[1:02:43] Has it been used for real-life oil spills or more in lab settings so far?
Rajasekhar:
[1:02:47] Sorry?
Keller:
[1:02:48] Has that technology been used in oil spills? Oh, yeah, yeah, yeah.
Rajasekhar:
[1:02:51] Yeah, yeah. Yeah, we could demonstrate this application in one of the events locally.
Yeah, yeah, it can be used.
Sure.
Brent:
[1:03:02] That's great. Yeah. We're kind of running out of time here.
Rajasekhar:
[1:03:05] Yeah, yeah.
Brent:
[1:03:05] So do you want to plug the second major you're working on?
Rajasekhar:
[1:03:11] Yeah.
Brent:
[1:03:11] Yeah.
Rajasekhar:
[1:03:12] So I mean, I've been very passionate about sustainability as a researcher, as an educator.
Then I thought I should make a difference to the learning community, and especially in terms of enabling them to find jobs of their interest and then grow.
In terms of professionally. So the reason is that, this is about the second major that I was keen on, is because these days, you not only change your jobs, you have to change your careersfor every four years or five years. So you want to be future ready.
And in terms of being future ready, now we are talking about climate change mitigation. You're talking about climate change adaptation.
[1:03:59] We are talking about sustainability as a whole, right?
So it's very important to have the next generation of problem solvers and with the capability of addressing sustainability issues proactively.
And what's even more important now is that every company has an obligation to submit ESG report, environmental, social, and governance report.
That requires deep knowledge in sustainability.
[1:04:31] So then what I thought is like, you know, I could sort of introduce a course. And initially I tried this idea called a culture of sustainability.
Then I said, well, no prerequisites, you know, to my students.
If you are interested, come and sign up for the course.
It's my challenge. You know, it's my job to educate you, to, you know, get you excited about sustainability.
Give me a chance, I will do that. I've done it. And there's a lot of interest from students.
So I wanted to go beyond that. Just one single course, singular course.
But how about having a program? gram okay then at the same time we don't want to disrupt ongoing operations it does the coursework requirements the students have to stay longer haveto pay spend more money which is not good so we have to sort of readjust the curriculum in such a way that this room for students to do the second major right and that's what i have donewhat i have done is to provide provide double-counting opportunities.
[1:05:30] So like if you do 40 credits equivalent to 10 subjects, you do your second major.
But out of 40 credits and about 16 credits for subjects can be double-counted towards the first major and second major.
So regardless of major you do, it could be in medicine, it could be in sociology, business, you name it.
We have open-door policy. So then we will try to do this kind of double counting and up to 16 credits so it's essentially you do only uh you know 24, credits overall right and then we havea whole bunch of subjects over here and then we get different layers of the curriculum and the first one is the primary requirement prerequisite but, for that major but not otherwise thenyou have core subjects about four core subjects uh being offered the second year so five courses are kind of core you know at least more like the the basic competency you should have insustainability.
And the remaining five courses out of 10 are optional electives.
So then we have a whole bunch of options being provided through various baskets that could come from different programs.
A student could sign up for those electives or even project, finally a project that could be double counted, right?
So at the end of the day, you have a transcript which reflects.
[1:06:52] You are a certified sustainability expert, right? And who can make a difference.
So when you're competing for the same job with others who have deep knowledge in a particular domain with little exposure to sustainability, even the competition, you are able to standup and tell your future employer, look, you know, I know what you are doing.
I know what your future goal is. You know, I can help you meet your requirements, because I have this knowledge, practical knowledge, and so on.
So what I try to do is to bring some experts from industry industry who can interact with students and let them know what the industry is looking for apart from the academic knowledgewe generate and so then in addition to that i also involve.
[1:07:33] Co-supervisors or co-advisors coming from other programs so the students can get the best of both, and so it's basically an interdisciplinary program very flexible super flexible isvery much relevant to what the world is looking for in terms of achieving sustainable development, and we call it sustainable urban development because 70% of the human populationwould live in cities primarily in future.
Right now it's 60-65%. So when you have 10 billion people, 7 billion people will live in cities, and then we have vast consumption of resources in cities, you know, in return we spit outmore carbon.
Our 70% of carbon would come predominantly primarily from cities.
So if we can tackle problems in cities and make cities more livable, more sustainable, more climate resilient, the global community will benefit.
That is the idea behind the second major.
Keller:
[1:08:31] Yeah.
Brent:
[1:08:31] I think it's a beautiful message to end on.
Keller:
[1:08:33] That sounds like a great program.
Rajasekhar:
[1:08:36] Thank you. Thank you.
Brent:
[1:08:37] Thank you. Yeah.
Rajasekhar:
[1:08:38] Thank you very much again for the opportunity to talk to you both, Brent and Kramer.
And I really appreciate your enthusiasm in engaging you know professors and research community, in sharing their knowledge with the global community and I cannot believe that youhave only undergraduate students you know I wish our graduate students can do the same thing like what you are doing and so all the best keep in touch thank you very much thank you.