Arun Majumdar: Energy, Climate and Sustainability – The defining issue of the 21st century

greetings everyone from stanford i’m actually here in my backyard uh very close to the foot of the dish trail as catherine said i’m dean of the school of engineering i’ve been dean for a little over three years now and i’m delighted to be introducing the school of engineering second major virtual event for alumni and i understand we actually have over 1 100 people registered for the event coming from all over the united states and the world so welcome to everyone like all of you here at stanford we’ve been spending the past few months adjusting to new ways of doing things the large majority of us like myself are working from home and we’re expecting to work from home for for quite some time to come but we we have been reopening some of our experimental research labs we’ve been doing it with very slow and careful approach uh over the past many weeks and ramping up slowly we currently have about 100 labs that are operating uh at reduced capacity uh with strict protocols and restrictions of course to ensure the health of our community our labs in the school of engineering do work across a wide range of research areas and activities but it won’t surprise you that there are many new projects specifically relevant to the virus though you might be surprised to know that we actually have coveted related projects across all nine of our different departments and disciplines so it’s not restricted just to the the biorelated areas you can learn more by looking at our website this summer in addition to the research ramp up our faculty are also thinking about new modes of teaching we really want to continue to provide a top-notch education to our students but most classes will be remote in the coming year and of course we’re all finding new ways to collaborate and i’m pleased we’re finding new ways to connect with you our alumni you are so important to the school and the university so thank you for joining us today and and please be on the lookout for future future virtual events that will occur in your time zone and around the world so as you’re all anticipating today we’re going to focus on the great work our faculty are doing in the field of energy research and the discussion will be led by arun arun is a faculty member in the department of mechanical mechanical engineering he has additional affiliations in the materials science and engineering department and the department of photon science at the slack national accelerator lab up the road arun holds the jay precourt provost jill professorship and he’s also co-director of the pre-court institute for energy in 2009 arun was the founding director of the advanced research projects agency and energy which is known fondly as arpa-e it’s a government-funded research agency that’s been instrumental in funding energy-related research so arun has been involved in this this area from a national and international perspective for a very long time from march 2011 to june 2012 arun was the acting under secretary of energy for the u.s department of energy after arun left washington dc and before he joined stanford he spent some time as vice president for energy at google arun is a highly distinguished scientist and engineer he’s a member of the national academy of sciences the national academy of engineering and the american academy of arts and sciences is quite an accomplishment and just on a personal note arun and i co-chaired a school of engineering strategic planning process not long after he arrived at stanford back when i was an associate dean and was a real pleasure to work with him so i know arun well and just have the highest respect for him and i know you’ll enjoy hearing from him today arun is going to talk for about 30 minutes and then there will be a question and answer period which will be moderated by will tarpe will is on the faculty in our chemical engineering department and he’s also affiliated with our department of civil and environmental engineering like all of you will is a fellow alum he received his bachelor’s degree in chemical engineering from stanford in 2012 and i’m hopeful some of his classmates are here on the call will earned his master’s and phd degrees from uc berkeley then he was a postdoctoral research fellow at the university of michigan and he returned to join the stanford faculty in 2018 will’s lab focuses on the recovery of resources from waste and also sustainable access to sanitation for all will is one of our newest faculty members he does great work he’s off to a great start and i know you’ll enjoy getting to meet him as well so i’m sure in conclusion that today’s discussion will be extremely interesting all around thank you all again for coming we do look forward to the day we can host you for events and visits to campus and now welcome arun and will great um first of all jennifer thank you

very much for the very generous introduction i also want to thank will for joining me in this one i’m sure we’re going to have a great conversation and thank you catherine and the whole team uh behind the scenes who’ve made this all happen and make us look good and appreciate all the people who are joining good morning good afternoon good evening to all of you i thought what i’ll do is to set the stage with a brief presentation to just to set the context and i really look forward to the q and a session after that and i know some of you have submitted your questions and i’m sure there’ll be many more so let me start the presentation and see if it comes on line okay so i hope you can see this so let me first start by what is the issue out here and how big and daunting is the challenge and what is the time scale that is really needed to address this challenge first of all i want to point out a plot of the world population over the years for the last 10 000 years and you can see it was pretty flat and there have been a few pandemics in the past where the population actually went down quite significantly and and then you have a massive increase in population over the last few hundred years to about seven almost eight billion people today where is this going well the world population is predicted to max out at about 11 billion people by the end of this century and so this is a you know we’re going to add another 3 billion people which is the roughly the population of china and india put together that’s going to happen and most of the population growth is going to be in africa and a little bit in developing part of asia as well while the population is growing the numbers are growing have grown what is remarkable is over the last 150 years the per capita gdp has grown exponentially not just the gdp the per capita gdp despite the population growth has gone up grown up exponentially and this has this has only been in the last 150 years or so and life today is fundamentally different from what it used to be about 150 years ago so let me give you a glimpse of that this is what life used to be in the past it was mostly an agrarian society we had farms with most of the people lived in villages and it’s a rural community some cities but not that big as we see today and transportation was mostly by by by animal power and what we are now seeing after 150 years after 10 000 years of this we are seeing over 150 years we have electrically lit and air-conditioned homes we can watch television in our rooms looking at usain bolt to run 100 meters or 200 meters in this case we have health care system that we never had before the life expectancy has gone up from an average about 35 or 40 years to now 70 or 80 years or yeah and increasing we have we have the world’s information on our fingertips and we are transporting ourselves in cars or planes and we still use the same term horsepower but instead of one horses we can put 100 horses in the in the engine of a car or 100 000 horses in the engine of planes in a in a space that was unthinkable 150 years ago this is what we call the industrial revolution which is literally going from horsepower to horsepower this has been a silent revolution going on and frankly this is still continuing to happen in terms of automation and will continue to happen for many decades and centuries to come now this all has been enabled by the use of energy you take away energy and it goes away and and this is what has these uh energy distribution and delivery infrastructure are really the arteries and veins of modern economies the grid the electricity grid which is so fundamental this was this is still the same architecture of the tesla nikola tesla and thomas edison so i call it the tesla edison architecture of the grid

and we have oil that was discovered in pennsylvania in the 1870s 1860s and now we have the whole history of of oil in the world which started here and spread around the world and we have massive infrastructure to move energy from one part of the world to another part and this is has fundamentally changed and transformed the world and has enabled all the things that i talked about previously but this has consequences as we know today fossil fuels provide 80 of the primary energy in the world there are a few non-fossil sources but they all add up to about 20 although they’re growing fast and this has consequences in terms of co2 emissions greenhouse gas effect and as well as global warming how big is the effect well we are trying to keep things below 2 degrees celsius as the global average temperature rise but that is the average averages don’t give you the details and the devil isn’t really in the details so you find that in the in the north and south pole the warming is higher the air temperature has gone up on an average by you know three or four degrees it has melted the ice in in greenland the sea ice has gone down substantially and it’s not just the sea ice now we are finding the land ice has is also going down not just in greenland but in antarctica as well this year siberia is facing a heat wave that it had never seen before you’re seeing temperatures on the order of 30 to 40 degrees celsius in siberia and this is just one instance if you really look at the statistics here is a plot of summer temperatures around the world from the 1950s and 60s some summers are hot some summers are cold but what we are seeing is the distribution of the summer temperatures is shifting to the right and we are witnessing high temperatures which are four to five times the standard deviation at probability is about 10 times what was there in the 1950s and 60s so while siberia is in the news to today this year some other parts will be in the news next year and it is not surprising that we are seeing all-time high temperatures recorded ever in the last few years around the world so this effect is going to come to your neighborhood some of one of these years so this is not going to you know insulate anyone from these heating effects so here’s a pop quiz since you’re all many of you are stanford alums here’s a pop quiz i’m going to give you a number and i would like you to think about what that means what are the units of that don’t worry there are no grades for this pop quiz but here we go first number is one and this is the number this is one degree celsius this is the global average temperature rise since the pre-industrial revolution levels it’s about 1.2 but its whole number is 1 the next number is 2 this is the global average temperature rise that our target the paris agreement was for 2 degrees celsius and that’s the target the third number is thousand don’t worry this is not 1000 degrees celsius but this is thousand gigatons of co2 1000 billion tons of co2 if you are to keep the global average temperature rise below 2 degrees we have a budget of 1000 gigatons billion tons of co2 left the fourth number is 40 this is the rate of emission per year today is roughly around 40 billion tons of co2 per year just to give you a reference of what a billion ton means if you add up the weight of the 7.7 billion people in the world that we have today the total weight of all human beings is less than one billion ton and we’re emitting 40 billion tons of co2 per year the final number is 25 and that is we have roughly 20 to 30 years left after which the emissions have to be zero or negative so where are these emissions coming from they are coming from a variety of sources this is not a single source thing that’s why the problem is so complex electricity and heat is only 25 industries 21

transportation we think is a big emitter it is a big emitter but it’s 14 agricultural land use and forestry 24 so this is a multi-dimensional problem if you really want to address this we have to take a multi-dimensional approach so the question is this seems like bad news so what is the good news is there a good news out there there is and these are some energy game changes that have happened over only the last decade or two and that where it has come to prominence the first one is unconventional gas that is replacing coal and gas is roughly half the emissions you still need fuel to run the economy and if you can replace coal by gas which has happened in the united states and happening in other parts of the world uh this is a big deal and at stanford we have now a natural gas initiative that looks at upstream midstream downstream methane emissions which are this is a greenhouse gas as well as the international trade and the geopolitics of unconventional gas all put together under one campus-wide initiative called the natural gas initiative the second game changer is renewables renewable electricity today as the graph at the bottom this is solar and wind the on the vertical axis is the the business contract the purchase price of electricity generated by wind and solar solar is the yellow wind is the blue and the black dashed line is the cost of electricity production from natural gas and what we’re finding this year and even beyond and it’s still going down it’s really like the moore’s law of the la of renewable electricity that we’re going to find this to go down even more and it become the cheapest way to produce electricity that’s a great news this is the first time in history where we have carbon free source of electricity at scale and being the cheapest way to produce electricity and finally as you all know this is electrification of transportation and the battery costs have come down even faster than solar and in the next few years it’s going to reach about 100 dollars a kilowatt hour that’s the capital cost of a battery why is that important it is important because at 100 a kilowatt hour the range and cost of electric car becomes competitive with a gasoline car without any subsidies and beyond that it actually gets cheaper and as many of you know it’s it’s lower maintenance and everything so this is the next 20 30 years you’re going to see a major uptake of electric vehicles but if you think that this is enough to address climate change you have to think again we this is such a complex and daunting challenge we need much more we need in addition to all of that great scale storage for long duration storage and for long duration it has to be at one tenth the cost of lithium-ion batteries lithium-ion is gonna not gonna make it there so we need new technologies to come in small modular nuclear plants at roughly half the cost of what it is what it takes today in the united states this is the cost that you find in korea in south korea and we our cost is about twice that and we need to reduce the cost of nuclear because that is today in the united states the largest carbon free source of electricity refrigerants are have a greenhouse global warming potential 2 000 times that of co2 and leakage of refrigerants will give rise to anywhere from 10 to 40 percent of global warming buildings consume 75 of the electricity and they’re very leaky so how about zero net building at zero net cost because then it scales industry probably the hardest thing to decarbonize is the indus industrial heat for steel concrete petrochemical processes and the role of hydrogen is a very important one out here and food and agriculture we talked about food wastage contributes but roughly slightly less than the u.s total co2 emissions the global food wastage so there’s a lot to be done out of there and then of course the global carbon management we have much higher fluxes of co2 due to photosynthesis than we have for the emissions so could we leverage that and somehow to store the carbon from the atmosphere introduce negative emissions and bring it down and store the earth finally as you can now see this is this affects what we are going to do in the next few decades will affect not only the electricity industry oil and gas in the fuel industry

the transportation the agriculture construction so if you think about it this is pretty much a large segment of our whole economy and not just the us economy but the global economy it’s a global issue so let me stop there and we can get into questions but i just wanted to set the stage for the discussion of the scale and the timing and the urgency of the issue thank you fantastic thanks very much arun arun has graciously left us plenty of time for a discussion so i’ll just remind you that uh anyone can add questions to the q a at the bottom right of your zoom screen and all of us can be uploading those questions and i’ll be pulling from those as well as um ones that came in before so arun i think let’s start with um you you painted out a fantastic picture of the many challenges and the motivations for addressing climate change um one of the ones i think is is most interesting and it came up in some of the questions earlier was what can we do about it and the we goes from individuals all the way up to institutions um so maybe we can break that we down into maybe students who are deciding what to study uh high school students undergraduate students who are deciding what to study those who are in careers that maybe don’t seem adults who are already in careers but maybe it doesn’t seem like they can work directly on climate change what can they do as individuals and then also what can institutions like stanford do um about climate change well let me address the um sustain of let me address the student issue and the career path because i think this is important for students i wish i was a student right now undergraduate because this is such an exciting time and will you and i have worked closely together in crafting a report on the new school of sustainability at stanford right and so that’s been selected now as the way to go move forward for stanford that’s a very important thing one of the things if you recall will you and i found that sustainability in our work that we did on campus sustainability pretty much rests in every school every department and it is again it is such a broad issue that there is no one single major that can address it the good news is that if you want to major in law you will find a place in this if you want to in a major education you will find a place in this if you want to major in public health you will find a place in this of course if you want to major in chemical engineering as you have will you will absolutely find a place in this and so this is one of those things that this is so broad that people will find a place in addressing this and as we have now seen some of the big tech companies like google amazon microsoft and apple they’ve all pledged to make themselves carbon free and they’re using their tools and their supply chain to do that so i think this is this is a collective responsibility for everyone for institutional organizations but as for career path the best thing i can say is for people to go to college first it’s very important that you go to get and get a great education um and then go on to a career but connect it to energy climate sustainability because the next few decades i i think the next decade i call it the roaring 20s for clean energy and so this is very exciting now for that’s for students for institutions let me just say that there are lots of discussions going on at stanford itself as to what should be the stanford statement on on energy and sustainability and climate i am of the belief that if stanford stanford should be aggressive and progressive in this area and should lead the way and we have targets which are more aggressive so that gives breathing room for many countries that don’t have an economy or a modern economy to actually grow so we should be ahead of the game in that sense but we also should be careful in making sure that when we make a statement it not only has an effect on stanford but it has a catalyzing effect on a broader ecosystem that we live in just to give you an example we there are different kinds of emissions there are scope one emissions the scope two missions and scope three missions scope one emissions are direct emissions and we should be absolutely reducing that very quickly but the most difficult wants to to reduce other scope 3 emissions because that depends on the supply chain if you buy stuff if you build a construct a building somewhere

there’s steel concrete and all other indirect emissions that come in and we should have a plan for how to affect the scope 3 emissions because that will have a catalyzing effect on our supply chain and every institution should be thinking this way how do you affect scope 3 emissions because then it has a catalyzing effect on the rest of the world so you know so those are the kinds of things that we have to talk through but in terms of mechanisms of how to achieve that and we have been taught having a few discussions um you know frankly there’s a lot of discussion of why not put a carbon price a carbon tax or carbon standard somewhere which will provide some discipline and a mechanism for institutions to really reach those carbon goals that we have so it’s not enough to make a statement we also have to have mechanisms if you are to invest in something maybe we should require those corporations that we invest in to have a carbon public disclosure so that they actually disclose what their goals are and how much they they’re contributing to the emission reduction because we should evaluate them and once everyone starts disclosing maybe stanford should set the standard for that once people start disclosing then having a global international carbon price becomes much easier so i think institutions can play a very important role in catalyzing before even the government can agree on what that pricing or what that mechanism ought to be because we could we could do it ourselves so those are the kinds of things i think we could do and individually you know we our biggest lowest hanging fruit that is very hard to get at is energy efficiency our our homes are leaky you know and are it’s very difficult to find exactly where they are but if you spend a little bit of time you could reduce emissions from your home and how you live uh if you eat one less day of meat that has a big effect so there are the personal choices you can make that has a huge effect on carbon emissions of course people think that electric cars can you know can reduce emissions they will reduce emissions if the grid is clean but there are other things that we don’t often see on trying to insulate our home trying to increase energy efficiency buy you know really efficient appliances but use them in the right way uh those are the kinds of person choices that can go a long way absolutely yeah i think one one thing that i was really impressed by when arun you and i were serving in this committee was the fact that we had i think 19 faculty members on this committee that started to define the structure and they were from all seven schools at stanford um and there was never a discussion where someone’s perspective wasn’t relevant um so i think that’s just a huge huge testament to on a bigger scale we really do need everyone on this very um intersectional challenge there’s a few questions and one that’s in the in the top of the chat that’s a little bit focused on technology but also market readiness um and the idea behind it is that solar hydro wind energy possibly even nuclear you could say are have been proven to be economically viable in some contexts so let’s look further down the pipeline in some ways farther into the pipeline what are some of the market-ready climate energy and sustainability solutions that are currently underfunded and under leverage that with a little bit of a push could take the same trajectory as these now more established um alternative technologies actually i worry about nuclear i’m a big fan of nuclear because it is a carbon free source of electricity but it has to the way our markets electricity markets are structured it is the price of electricity is going down because of cheap renewables and frankly the price is often decided by the price of gas is the marginal cost that is needed to address the demand and that price has been suppressed because of availability of a lot of gas and low cost renewables and as a result of that it’s becoming harder and harder for nuclear to survive and if you really want to build so the two issues one is how do you make sure that the new the current nuclear plants we have about 90 something of almost 100 nuclear plants in the united states they need to survive first of all they need to make enough money to be able to pay off their loans and extend their lifetime but if you’re going to build a new nuclear plant that cost as i mentioned earlier in my talk has to be half of what it is today otherwise it’s going to be very hard to get financing it’s going to be very hard for them to survive in today’s elect competitive electric electricity markets so uh even though nuclear is mature um

i i worry that there needs to be innovation in that continuously and frankly right now we are seeing tremendous amount of innovations that are going on in the nuclear frankly in the private sector which is terrific and these are small modular nuclear reactors not just the new scale one that we hear about but many others some of them in the bay area interestingly enough so that is something that you know i think has to be there in terms of carbon management i think one of the biggest challenges is negative emissions if you are to look at any study that says that you know if you are to keep the temperatures below 2 degrees every study that we have seen suggests that at some point 20 70 onwards 20 60 20 70 onwards we need to start having negative emissions maybe even earlier if you can that is not trivial because co2 is very dilute and so one of the ways is to leverage and harness the biological the the natural co2 cycle where you have about 400 billion tons of co2 that is cycled every year through the through our plant system around the world could we tweak that by one or two percent to really make a big difference and store the carbon in the ground i think we need a lot of research in going into that there’s a lot of interesting discussion going on on direct air capture by chemical means and i think that’s expensive today that cost is coming down and we need to do research and create the options for that and see how much can we reduce the cost to make it viable so those are sort of the technological arms and there are many more by the gritski i’ve lined it up you know at the end of the the things that we need to do to develop technology but this is more than just technology this is issue about markets we need a carbon price a carbon standard of some kind i don’t care what it is actually i do care what it is but frankly at this right now we have not very much in terms of carbon economy wide carbon price so those are the kinds of things that we do need to have to really bring this to scale it’s not enough to do this in the laboratories of stanford it is really important to take it out understand the the inventions and the discoveries that we make and turn that into innovations at scale and that would require some kind of market mechanisms to make that happen so that it’s a signal it’s a predictable signal to the business community for them to pay pay attention to this absolutely yeah we see the awareness increasing individually can then make a signal to companies like you’re saying to be more transparent with their information and also to be more intentional with the their innovations right towards once we see their customers start valuing things um maybe let’s take that idea of scale and get a little bit out of the lab so to speak and maybe we can come back because there’s some other questions but i want to make sure we’re kind of speaking to several audiences here so um maybe two related questions first um how do we think about what climate change adaptation is going to look like in the global north versus the global south some people call this the just transition right and the most industrialized countries how do we adapt to climate change versus in developing urban centers in africa where much of the population growth is going to be over the next over the rest of the century um how do we address that and if we can also connect that to the moment that’s on everyone’s mind right now is um uh effects on emissions due to covid right due to shutdowns right are there adaptations there like someone in the chat hadn’t had was bringing up the idea of like voluntary shutdowns like maybe a week a month or something or something like this where people voluntarily shut down to temporarily reduce emissions well let me address it in a two-fold answer one is that as as i pointed out most of the population growth and economic growth is going to be in developing economies so if you are to address this as a global challenge uh we have to look at a those regions of the world where the people want to be prosperous and and we should enable that to happen and we should i think we it’s very hard to put the burden of climate change on those economies that are trying to develop right now because if you look at the co2 emissions the history of ceramic emissions and the lifetime of co2 molecules in the atmosphere that is responsible global warming is several hundred years and so the co2 that we have emitted during the beginning of the industrial revolution

is still active for global warming and if you look at the contributions most of the oecd countries have contributed to the co2 that is leading to global warming so we have a responsibility to enable the rest of the world to grow and at the same time enable and have us reduce our emissions but the opportunity out here is the following that we have the infrastructure let’s say the united states the energy infrastructure today was designed in the 20th century and we need a 21st century infrastructure in many parts of the world where the economy has not yet been developed the infrastructure does not exist and i think here’s an opportunity to enable them to leapfrog into the 21st century infrastructure as opposed to bringing the 20th century infrastructure to them and so i think this is i would almost look at it as an opportunity but also a global responsibility to enable them to grow so so that was the first part of the second issue about what do we learn now that could help in the process actually we have to be very careful so if you look at the reduction emissions due to cobit 19 it’s gone down by about there was a recent a report from the international energy agency our emissions have gone down by eight percent and that’s because oil demand has gone down by nine percent coal has gone down renewables actually has gone up by one percent interesting enough but as eight percent the question is are we going to rebound back we want our economies to rebound back are the emissions going to rebound back the bad news is that at the in the 2008-2009 financial crisis the emissions also went down and then it went back up and that kept along the same trajectory as before 2008 if we go back to that we have a problem in terms of emissions so the question we have to ask ourselves is that could we use this crisis as an opportunity to really have sustainable innovations being brought to the market and turn around in these investments that we’re making in stimulus investments that we’re making could we use that as an opportunity to turn our economy around to becoming more clean and still have economic growth but try to decouple economic growth from emissions growth and i think that’s the biggest challenge and i have an op-ed that is there in in in the hill that came out last month on this particular issue how do we best utilize our stimulus so right now the government the first stimulus of two trillion dollars was really a survival stimulus it wasn’t really it was survival because people had lost the jobs we hope that the next is to the next tranche of stimulus is really to stimulate the economy and to create the infrastructure for the clean energy future of the 21st century so those and there are many plenty of jobs there as well so that i think is what the not just the united states but the rest of the world has to see yeah i think that that leadership of what you’re getting at decoupling emissions from from economic growth and economic vitality is really critical if i can i’ll just plug the the op-ed you just mentioned you sent it to us and then i send it along to my research group and we had a great discussion about it so i think it was sent out with invitation but if not um you can find it fairly easily online uh with the room’s name and uh the hill um great so i think another thing that caught my attention when you were talking a room especially about this just transition idea is about the leap frogging that can occur in some developing economies where there’s not this sunk cost in in uh frankly obsolete infrastructure right um or super soon to become obsolete infrastructure and uh one thing that comes up in in my field of water treatment is we say the same thing about sanitation infrastructure and water infrastructure and so this is the idea that comes up a lot in terms of the water energy nexus and kind of has been added to it water energy food because these are kind of intricate intricate and interconnected systems so there’s a question here about what are some of the most promising technical solutions for agriculture and reducing emissions especially because in the pie chart you showed for greenhouse gas emissions globally agriculture and forestry i think we’re another quarter at 24 of those that’s a great question and in fact the plenty of opportunities um right now if you look at the as i said if you look at the emissions by sector food wastage if you just look at food wastage we waste about 30 to 40 percent of our food around the world in the developed world it’s at the consumer end we just don’t eat everything on our plate now when i grew

up back in india our mommies tell us that you know you eat everything on your plate you don’t leave anything that’s my habit and of course i put on weight because of that but that’s you know that’s a separate issue but because of that um you know because of the wastage at the consumer end we are wasting 30 to 40 in the oecd countries in the developing economies it is in the supply chain of food and from the farmer to the consumer there are no refrigerated or the very few refrigerated supply chain and so there’s food waste again about 30 to 40 percent and there the price of food really matters in united states the price of food it matters but it’s not as big a fraction of our income but in those parts of that survival and so addressing food spoilage and and using the food that we have actually grown is kind of a low-hanging fruit but it’s not an easy problem to solve the refrigerant supply chains etc and behavioral issues in in the developed world so that’s one the second is that you know we if you look at uh plants and crops that we have if he could somehow figure out how to develop plants with deeper roots and with more lignin content that we can grow not just for our crops but for forestry what that would do is to grab and to do it at a rate that is fast so can we make uh trees grow as fast as bamboo that was a very fast-growing plant but can we make them grow because the rate is important and and have them scale in many parts of the world so and if you can grow deeper roots it is well known that the degradation of carbon goes exponentially down with the depth of soil so if you have the deeper the roots they will stay there for a while so those are the kinds of things in food and agriculture which and and there are many other aspects of it as i said changing from from meat to uh meatless uh diet a it’s you know good for health if you go go off red meat and if you just do it and this is a behavioral issue if you just do it once a week that has a huge effect on carbon emissions great fantastic arun is a follow-up to that on kind of the personal emissions and there’s a question here that’s about how do you see that kind of tracking of personal emissions and personal consumption playing a part in tackling uh climate change what can we do to kind of close the link between seeing the data and turning it into action of individual consumers that’s a great question there are lots of tools on the internet of personal carbon calculators and things like that i mean you could use that i mean a simple way to look at it is how much you travel um you know how much you and you could use your data put it that put that in your on these websites and actually calculate uh how much you make but frankly that’s the easy part the difficult part of the supply chain the clothes we wear the textile industry is roughly eight to ten percent of the global emissions of co2 textile so and the food thing those are embedded emissions that are the steel and concrete that we use for for buildings um and so those are harder to calculate but they can be there’s we have a whole research in arm or several faculty at stanford in school of earth sciences energy resource engineering that look at and school of engineering they’re looking at life cycle analysis um it’s it’s not easy but it can be done and the the embedded emissions are the really difficult ones to handle absolutely um great i think there’s a question that maybe i promise i don’t think this is a plant but uh it’s a question about what’s the current research happening on batteries which i imagine you can speak to from your affiliation with the pre-court institute well there are multiple kinds right i mean you have lithium-ion battery still has lots of headroom and there’s tremendous research going on in material science department up at slack in school of earth on batteries not just batteries the chemistry of electrochemistry batteries but the battery system management we have a new initiative called storage x which is focused on storage broadly a large chunk of that is lithium ion batteries but as i mentioned if you really want to look at long duration storage for the grid and you really need long duration if you want to have 70 80 penetration renewables on the grid which a lot of people like to have and

frankly it is now cost effective and scalable but you’ve got to have storage there long duration storage 100 hours multiple days and for that the cost has to be much less lithium ion is not going to make it and so that’s a big issue and that’s a research area that many of our faculty each way will chew and many others are are focused on um there there are issues of battery recycling which we’re not facing today but at some point with the amount of batteries that we’re going to have we have to figure out how to recycle them for environmental reasons and frankly for economic reasons because lots of good materials a lot of good cobalt and manganese and and lithium in there that we can recover and then i i really think not this is not just stanford but broadly as a nation as the united states we need to figure out how to create a battery supply chain in the united states there’ll be many many giga there’ll be roughly 100 giga factories that need to be built in the in the world to supply the batteries for lithium-ion batteries for transportation and and out of those we need to build a few in the united states so that the research that we do at stanford and many other places has a place to go and the feedback loop between manufacturing and markets to the signs is very important for for the science to be relevant and so um so that that manufacturing you know we have a gigafactory and a few gigafactory in the united states but we need many more and i think it’s very important to provide supply chain in the united states great thanks arun so we have just about 10 minutes left so i want to encourage everyone we’ve got a fantastic number of questions in the q a i want to encourage you also to upvote them so that we can try to snowball these and nucleate them together um there’s one that’s um interesting that’s about what are you what do you think are the five most important changes the u.s can take to become a global leader in adaptation uh to climate change given these huge challenges of scarcity of greenhouse gas emissions of climate change that we’re facing in this century i’m glad this has been brought up because i think it is there is a risk that we will exceed two degrees i think 1.5 degrees is kind of baked in right now and if you are going to reach two and a half or three degrees global average temperature rise we need adaptation and resilience absolutely critical so what do we need for that we need to figure out how to provide water because we’re going to see more droughts we’re going to see temperature extremes so water is going to be a very important commodity i know you’re working on that and and that is absolutely critical and this is going to be an issue not just the united states but many other parts of the world drought resistance agriculture and and adaptation to higher temperatures and you know that’s where some of the best science and biology and plant biology can is going to be very important um trying to figure out how to manage the electricity grid when you have heat waves you saw the the gaussian distribution move to the extreme to the right and we’re going to have heat waves we just can’t predict when it’s going to have where is it going to happen next year or the year after that but at some point it’s going to come and hit us so if that’s the case the grid is going to be under immense stress because everyone’s going to turn on the air conditioners how do we manage that so there i can go go down the line and then of course sea level rise and the coastal regions and there’s a lot of population in the coastal regions so these are the kinds of uh things that we have to adapt and people think it’s only the heat wave if you have an instability of the jet stream these are called the rosby waves you’re going to have cold waves as well and that’s also due to climate change so it’s not just the heat waves and when you have freezing conditions for a long period of time as we’ve seen for polar vortex etc that itself creates energy related issues because you need heating so lots of resilience issues out there and i think we need a concerted effort just like we’re doing for energy and emissions reducing the emission from energy system we need a concerted effort adaptation and resilience absolutely yeah this multi multi-prong strategy is going to be going to be critical as these problems start to overlap even more than they do now so we have a couple questions arun about kind of comparing different energy storage techniques right so what and maybe we can combine them by thinking what what are the metrics you think are important to compare things like methane versus coal or nuclear versus solar cost is one but you’ve mentioned life cycle analysis a

bit but what are the metrics the key metrics that you think are important when we’re comparing different energy sources or energy storage techniques especially in different contexts well certainly economics the cost is important the reliability of the supply is important so which means supply chain is very important so you can move methane from one part of the world to another part of the world by lng tankers uh we cannot do that for electricity from let’s say hawaii to the united states mainland the united states we cannot do that today so how you move energy but you can grow develop electricity generating sources in hawaii which is local so supply chain very important cost very important emissions from that extremely important reliability and resilience and security of the supply these are all factors that go in so in fact this is a broader statement i’ll make that whenever we look at energy related issues you got to look at the economics and what impact it has on the economy we have to look at the environmental impact of this and we also have to look at the security implications of this and any decision that we make if it does not address one of these three it could come to bite us back in the future so we have to balance our decisions based on economy environment and security because it is so fundamental in our economies today absolutely yeah and i think that multi-criteria optimization is really critical so that you don’t expose yourself like you’re saying down the road to a reliability issue because you’ve only optimized for the other two for example um okay it is unfortunately time for our last question but this has been an extremely interesting discussion maybe if i can summarize a couple of questions here we’ve got a question um that you and you hinted at this ebitda room about the role of electrolysis and kind of green hydrogen production in long-term storage of renewable energy to tail along with that um the broader question of what kind of out of the box options for energy storage uh beyond some of these electrochemical approaches as we know them and maybe a third part of that more broadly is what’s the role of decarbonizing kind of chemical production so to speak right and to bring that back to your pie chart industry broadly was 21 right and so this is something of course i think about in my discipline too though so to summarize what is the role of electrolysis and and green hydrogen production and storage what kind of other blue sky options are there for these approaches and third can we talk about decarbonizing industrial production as well well many of us feel that hydrogen is going to be a big commodity big important issue in the future and today hydrogen is produced mostly from reforming of methane using steam which has co2 emissions we are now witnessing a new age coming which is electrolysis of of you know water splitting using electricity using renewable electricity and that cost is coming down and there’s tremendous innovations going on not just the united states but china has also innovated in bringing down the cost of the electrolyzers that are used which is really really important but there are two factors out here one is the cost of the uh of the capex of the electrolyzers and the second is availability of cheap renewable carbon free electricity and that is coming also so we’re seeing the next few decades are going to be very important for this uh you know carbon free hydrogen but you also have to realize that there’s a lot of hydrogen in methane and if there’s a lot of r d also going on in trying to do methane pyrolysis in fact i’m working with matteo carnello in in chemical engineering on an rpe project to do methane pyrolysis to produce carbon-free hydrogen and produce solid carbon and that solid carbon could potentially be used for construction material or some other as a commodity and you have a two streams of products going out using methane pyrolysis and the good thing about methane pyrolysis is that you can move lng you can move methane from around the world using lng but and if you have the methane pyrolysis you’re actually moving hydrogen then and so that turns out to be uh important but still in the r d phase right now so for and the hydrogen is important to some extent but perhaps a smaller extent on transportation you know people think that transportation hydrogen is going to be a big deal well it’s going to be for a big deal for perhaps long-haul transportation long-haul trucking etc but you know it’s most of the use of

that hydrogen is going to be for industrial heat and and the use of the hydrogen for industrial heat for steel manufacturing for concrete manufacturing if you could decarbonize the hydrogen for ammonia production that’s a big deal or for that matter for petrochemical refinery work if you can produce carbon free hydrogen to enable that to happen that’s a big deal so i think we’re going to see a lot of hydrogen as a commodity not just for for transportation i think that’ll be a smaller fraction but for renewables integration for electricity power generation as well as for the industrial sector which is very very hard to decarbonize absolutely fantastic well i think we’ll end it there of course this is a continuing conversation but thanks to everyone for hosting a roon and for me right in your homes on zoom this was a great stand-in for an in-person event you