[Music] [Music] as i repeatedly point out we have to once we talk about electric vehicle we have to talk about capital cost and operational cost when we talked about ah ic engine vehicle and we talked about energy per se we never talked about petrol tank cost the cost of capital cost we only looked at petrol as a variable cost or operational cost here i have to take both into account operation cost of electric vehicle cost less than eight rupees per kilowatt hour is a cost of electricity actually it is if it is a more like home it is five rupees per kilowatt hour i have taken the cost that will be there if you char if you charge your vehicle using electricity in a commercial establishment so it is between five to eight rupees per kilowatt hour so operation cost is not that high will show you a kilowatt hour that it come out to a small amount of money per kilometer the key cost is the cost of the battery and i am getting into a little bit of introduction we will get into details of this later on and i have taken here four different kind sizes of battery one kilowatt hour two kilowatt hour three kilowatt hour and four kilowatt hour i have taken four of these batteries and the cost of the battery one kilowatt hour cost eighteen thousand rupees a particular battery 2 kilowatt hour 33 45 and 54 see that is not linear 4 kilowatt hour does not cost 72 000 rupees because larger the size of the battery lot of costs are actually there in one kilowatt hour and will carry on to four kilowatt hour incremental costs are less so between one kilowatt hour to second kilowatt hour you only increase by fifteen thousand rupees next third kilowatt hour you increase only by twelve thousand rupees and finally you increase only by nine thousand rupees now what i have done i have taken for two wheelers and for all two i have assumed let us take a 15 watt hour per kilometer 20 water per kilometer 25 watts per kilometer 30 white water per kilometer and for a auto forty water per kilometer and fifty water per kilometer now if i take one kilowatt hour battery what is the range that i get now how do i do that first thing that i have to do is of course battery cost is there effective use i cannot use full battery ever one of the thing that you will learn is that you can i use only a fraction of the battery you cannot fully charge or fully discharge that is called depth of discharge we will learn this in detail right now just assume that we can use 85 percent for battery capacity so though it is one kilowatt hour i can use only point eight five but the two way kilowatt hour i can use only one point seven kilowatt hour so given one point one kilowatt hour and i am using there for 850 watt hour if i use 15 watt hour per kilometer i actually calculate my total range that it will give me 56 kilo meters with 20 watt hour per kilometer i use little less range so if you see as the energy efficiency improves the range that i get in a one kilowatt hour battery keeps on reducing and after the same thing for two two kilowatt hour battery three kilowatt hour battery and 4 kilowatt hour battery using this i can now look at my capital cost as energy efficiency improves from 25 to 15 watts per kilometer one gets higher range for the same size battery or in other words for getting let us say my target is to get 50 kilometers range i my battery size reduces suppose i need only 50 kilometer range i will one kilowatt if it is a 15 kilometer wattage kilometer one kilowatt hour is more than enough two kilo if i range if my thing is 30 wattage per kilometer then i will probably need two kilowatt hour double the size of the battery which means my capital cost doubles so i i actually put this whole thing so that you can get a feel that what it means for example suppose i want to get hundred kilometer range a question that i am asking compute size reduction when my ray my efficiency increase improves from 25 watt hour to 15 watt hour what happens so for my 100 kilometer range and i can use a blank slide or i can write here for 100 kilometer range and suppose i use 25 watt hour per kilometer my battery size is how much 100 kilometer range 25 watt hour so 100 and i need 25 watt hour per kilometer multiplied by what percentage of battery i can use 0.85 oh sorry divided by divided by not multiplied divided by because only 85 percent of the battery is usable that comes out to be two point twenty nine hundred watt hour or 2.9 kilowatt hour okay if on the other hand instead of 25 water over kilometer i use 15 watt per kilometer my battery size will be 100 multiplied by 15 divided by point eight five and it goes down to one point eight now from this table i can see that two point nine kilowatt hour battery will be between thirty three thousand and forty five thousand rupees it's close to forty five thousand but slightly less i can calculate that i can assume the linear between thirty three thousand to forty five thousand twelve thousand rupees per kilowatt hour so for point nine i will require only ten point ah approximately 10.5 above this so my cost will be around 43.5 kilowatt but for for similarly for 1.8 kilowatt battery my cost is going to be eighteen thousand plus for eight hundred i have to do that and that comes out close to thirty thousand rupees so if you see that what i am pointing out if i improve my wattage per kilometer my cost of battery goes down okay so this is a simple calculation we will do more detail calculation later on when we actually compute the battery cost here we are talking about the capital cost only and therefore i have given you an assignment a very similar question a two-wheeler uses 25 watt hour per kilometer and we need a range of 80 kilometer keep that 0.85 effective usage in mind calculate the size of the battery required and estimate the cost of the battery by looking at that table the table that we have given you on the previous slide and remember that you won't get the exact number so you have to do linear interpolation between two points and compute that and submit that as assignment so i have actually given you two assignments now one i gave you earlier now another you need to submit that in a week's time give you the date for submission later on let us go on and look at what else can be done we have already looked at that improving the energy efficiency will help us reduce the ah reduce the ah cost we have already looked at that is something that we have if i can improve my energy efficiency reduce the energy required per kilometer my cost goes down now this as i also pointed out basically requires improving the motor efficiency including the ah reducing the getting better tires with lower rolling resistance trying to make the vehicle aerodynamics better or lower weight now suppose vehicle is given to me and i cant do much more than that then what else can i do so let me look at it for example let us take what else can be done let us take a battery of a certain size as i improve the energy efficiency of the battery what happens i require smaller battery so for autos for example three years back our energy efficiency used to be 70 to 80 watt hour per kilometer that is amount of energy that they were used to use and once we figure out that these four things better motor and controller better tire lower weight and better aerodynamics will help the industry got together occasionally with academia and today it has reduced to 45 to 50 watt hour per kilometer same thing has been done for the buses buses used to be highly energy consuming 1600 watt per kilometer these are all pretty much technology brought from outside and then once it was understood the indian engineers got together and today it is only 900 watts per kilometer what does it really mean it means the size of the battery original size was what i see here now the size of the battery actually goes down by 35 to 40 percent why because you reduce the energy required by 35 to 40 percent size of the battery for the same range has gone down by 35 to 40 percent this has been done and has to be always done for any new kind of vehicle focus on energy efficiency what is the next thing can i reduce the battery size further instead of even using what i pointed out here can i can i use even less can i use even less if i use smaller battery what will happen it will give you a smaller range and a smaller range basically means that you start with a charged battery it's a small battery it has a limited range and you will run out of the range once driving and all the time it will make you worry that am i going to run out of range run out of battery why do you not worry about this in a petrol car well if you are about to run out you will get an indication in the vehicle and then you will go to the nearest petrol station and pretty much in most urban areas every kilometer to two kilometer you will find a petrol station and you will go there get the petrol filled in three to five minutes and now you drive when you talk driving electric vehicle and suppose your battery energy goes to nearly zero you know that you will run out in the next five kilometers the question is can you find a charger where you can charge your battery there are not too many petrol pumps are large number of charges are very small so you may not find even if you find one and go there how long will it take you to charge a battery charging takes a long time there is a whole focus on this and we will study this a typical battery is best charged in four hours even if you fast charge it takes 45 minutes 50 minutes so you cannot just quickly go to a charging station charge it and go further it completely messes up your program so you all the time worry about am i going to be able to complete that journey without battery running out of cha energy this is called range anxiety and along with e v has come the range anxiety so this is something that we have to worry about so yes by reducing the size of the battery you can reduce cost but you will create a huge amount of range anxiety and basically it becomes unusable what if you use a totally different strategy let's suppose it lets look at it suppose there is a three wheeler auto or a bus and suppose you use small size of the battery and you further split the battery into smaller size and you say you will use only one third of the size the battery it was designed for large battery but i will use smaller size as i point out if you use smaller size you have a small range and then you would have been worried about charging but what if there are large number of what is called swapping station swapping station where you go you give your battery and take another charged battery now that won't take more than four to five minutes maybe less three minutes you now have got equivalent to petrol filling time you can easily go and get get up swap a battery of course the other thing is proliferation of that you should get enough such battery swapping station where you can go and swap and suppose you have at every alternate street corner or even every three street corners there is not much of a problem so alternative strategy for india could be instead of having large battery use smaller battery and swap it at fairly large number of swapping station this was proposed three years back the question that many of the senior government officials asked which are they used to asking which other country has done it we said no one then we are told then how can you do it nobody has done it so it is infeasible well nobody has done it because they did not require it they could buy a large battery in india we cannot buy a large battery it will push up the cost will require small batteries and therefore why can't we be the first and most government officers don't have the courage to be the first to do something we may talk about atma nirvana or this or that will always like to follow this is a problem that we faced but we kept on talking about it that why cant you swap battery at least for the lower cost vehicles and maybe start with the public vehicle three wheelers and for the ah buses you can always buy a large battery in charge nothing prevents you but have that as an option took considerable effort but people have started seeing the merits of it and today it is important component of indian vehicles and therefore we will discuss this in detail the swapping there are other advantages another uniqueness about india which is distinct from that of the rest of the world india is a very hot country 45 degree centigrade temperature is not that uncommon in fact indian temperature nowadays reach up to 50 degree centigrade now these batteries that are being used are best charged at 25 degree centigrade as you start charging at higher temperature its life goes lower and lower and lower will learn about that if you charge at 45 degree centigrade it hurts the battery like anything so this is a big problem that india will face whether you have small battery or large battery you will face the problem how do you charge at 45 degree centigrade now in this swapping case there is a big advantage you go to a place give away your battery take away a new battery put it in and suppose it is easy to do it in three to four minutes drive along then you are given the battery which is now empty battery to this operator who is charging that person can charge it for in several hours first of all and actually charge it by cooling the charger itself can cool the battery you can have a cooling environment so you have a double advantage you don't have to fast charge and you don't have to charge at high temperature now we'll show you that both of these are bad for the batteries if you try to fast charge the life gets very badly affected if you try to charge at high temperature 45 degrees even 40 degree centigrade life gets very badly affected now if you swap both these problems can be overcome and therefore we are going to discuss this and that is a reason today public vehicles the shared vehicles are increasingly using swappable battery though there is still some resistance within the government most of the resistance has melted out it takes several years of trials and showing things for people to accept that but it is there now if you swap battery the question is who will be this person at the street corner who will give you support battery who will own the battery are you going to give away your battery what if you give away a good battery and you get a poorer battery all these questions arise so what has emerged is that you will not buy a battery a user will not buy a battery user will buy electric vehicle without battery wow my cost goes down like anything that's a very big advantage then i will go to there is there is a energy operator there is a separate business and we call that energy operator it is like a petrol tank operator petrol operator like what bpcl like iocl there can be energy operator this energy operator will set up a shop every third street they will own the battery they will purchase the battery so iocl will own the battery and you go there you swap the battery the only thing is that you can you have to tie up with iocl and only so i swap iocl battery at iocl station but assuming there are large number of iocl stations or bpcl stations you can go you have tied up with iocl battery have a contract you have taken a battery from them keep shopping with iocl keep going now since you can stop in three minutes probably smaller you will not get stuck now you can have a smaller battery you do not have to first user does not have to invest in battery battery actually becomes a convertible is a is a now operation cost for the user whenever they get a charged battery they'll use it when they return they have to actually pay for the battery rental as well as for the energy used this is the model that can be used and if it does then it significantly helps per proliferate the electric vehicle as far a user is concerned is used to buying a three wheeler auto at 130 140 thousand rupees they can still buy a 140 000 rupees even less without battery and they keep on hiring and renting the battery the only question will be how much will it cost the battery rental plus including the electricity fuel field battery cost i will show you actually it will cost less than the petrol and since people are used to paying it for petrol they can actually pay for this quite easily and the cost will keep coming down as the battery costs keep on falling the other question is will iocl or bpcl make money they are going to buy battery and lease out battery charge battery and take back discharge battery will they make money if they don't make money they will not set up this business the key question is can they make money can users still pay less than petrol this is the economics that needs to be worked out and we will work this economics out and show you in this course that this is indeed viable and this is the reason why people are setting it up and the public vehicles like three wheelers or even actually it can be purchased by a fleet operator ola can purchase it and in fact rent out the vehicle also the batteries can be leased out by energy operator and the whole business can flourish like anything so one of the first thing that i am pointing out i we mentioned that the cost of battery is very high this is going to be a big bottleneck we said that you improve the energy efficiency it will help and be sure that it will help next we sort of said use smaller battery and swap and bring in a concept of energy operator who will own the battery so the user gets all the benefit they do not have to purchase a battery they do not have to worry about wear tear of the battery it is the iocl and bpcl or the energy operator who has to worry about it they have to work out the economics you are renting the charge battery give it out whenever it is done so this is option number one this will work very well because you may have a 50 kilometer battery now a typical auto driver travels about 120 kilometer a day so they may have to swap the battery twice a day nothing no big deal they'll be traveling most of the day whenever the battery is running out they will go to one of these stations and swap it in three to five minutes and proceed similarly buses are typically running from one place to another place and at the end of every trip anyway there is a five to ten minutes gap that's the time they can stop the battery so for vehicles like two three wheelers and for buses which i call as a public vehicle this is a very very good model but suppose it is a private vehicle i am buying a two wheeler or a car and if i say well you have to swap at every 50 kilometer i would like to go to i do not like to go to petrol tap pump so often i will not like to go to a swapping place so often whether it is a two wheeler or a car car may have 100 kilometer even then i may not want to go that often so there can be yet another option so this i have already pointed out if you swap capital cost of the vehicle is less than that of the petrol vehicle and operation cost is less than that of the petrol diesel cng so there is a huge advantage the approach to is a private vehicle battery cost dominate so what happens people tend to use large battery tesla for example gives you a 550 kilometer range the cost of this is extremely high ah starts at 4 million rupees so that is not india's market of course it also means large weight which means more energy consumption reduce energy efficiency this is all right for tesla and for in india also of course there are enough rich men who can actually afford something like that that's all right numbers are small as i pointed out point five percent will not talk about it as we pointed out the problem is small vehicle will cause range anxiety you can do something called fast charge but that also takes 45 to 60 minutes and very fast charge pushes of the cost of the battery will deal with this subject also even if you have a charging station which can charge fast batteries are not capable of being charged fast batteries which are capable of being fast charged are far far more expensive than batteries which are not capable of being fast charged and if you try to fast charge at 45 degree centigrade or 40 degree centigrade you get hurt like anything so what do you do in countries like india you cannot use swappable batteries too often swapping but suppose you use what is called range extension battery suppose i have a car and i do 100 kilometer range i charge it overnight at my home 100 kilometer i can travel question is how often do i need to travel more than 100 kilometers a day probably five percent of time not even that maybe 10 days in a year most of the time people don't travel one of the characteristics of india is that vehicles travel short distances per day five days seven days a year is already large ten days so actually i need a solution for those ten days similarly for two wheelers suppose i have a 50 kilometer battery i charge it overnight how often do i travel more than 50 kilometers per day mostly no probably 10 days a year so do i have a solution for those 10 days the solution for the 10 days is that can i have what is called a second battery which i will call it a range extension battery so the vehicle has a provision for a second battery called range extension i do not use it every day but the day i need to travel longer distance i go to a one of the swapping station and they will add a battery so i know that today i am going to travel in a car 150 kilometers 170 kilometers i go there i get a second battery travel come back and return that but second battery first battery is always there charged similarly for a two wheeler if i need to travel longer distance the day i need to travel longer distance i will get a second battery the range extension battery so i have 100 kilometer base battery in my car another 100 kilometer range extension battery the question that will again be asked what if i want to go a long distance if i want to go from chennai to bangalore or let us say i want to go from delhi to agra and come back bombay to pune even 200 kilometer range will not be enough well i start with my charged battery 100 kilometer i pick up a battery at as soon as i go out so i have 200 kilometer range i first use the range extension battery so after about 100 kilometer it would have run out i travel typically that kind of distance in about two and a half three hours i stop for a cup of coffee that time the range extension battery is taken out and a new battery is put the iocl petrol pump is there also the battery stopping station is there also they will take out my battery and put a new battery now i can go another 100 kilometer i have got 300 kilometer range and i have to repeat it once again if i need a 400 kilometer range and i can do the same thing for my two wheeler i start with a 50 kilometer add a battery of 50 kilometers i have got a 100 kilometer range if i am going long distance stop after 60 70 kilometer get the battery swapped have a cup of coffee and continue so the range extension battery could be another way because i do not need it every day i need it only once in 10 days in a year maybe once in 15 days i do not have to invest for that let iocl invest and of course iocl business should work they may will charge me they may charge me slightly extra but i should be willing to pay slightly extra for the day when i have to go longer distance even details of what will it cost is being worked will be worked out in this course so the shopping will be done by the same energy operator who purchases the battery and keep the charge battery ready for swapping of course the third option is a conventional approach which is used all over the world and there we can easily say well we will follow what the world does choose the right size of battery which is enough most of the time slow charge it normally fast charge it once in a while but if my range is good enough most of the time i don't need it if i go longer distance i'll wait for an hour and fast charge it that is something that can be done and of course that will bring questions where does one charge if this is an option the batteries what kind of do we charge at homes fine but that's not if you want to go longer distance at public places what are the public places where i can charge what are the charger what are the specifications of this charger what are the specifications of these swappable batteries is there a single specification how do you set up these charging stations is it a profitable business how do you set up the swapping stations is it a profitable business all these questions we will try to answer in this course so charging and swapping is going to be a very important component we will talk about what kind of charges what kind of swappers and we will discuss this in more detail in this course to stop with that