169 - Engineering car parks for EV's with Ali Ashrafi and Pawel Woelke

But the methods , tools that we use to solve those problems , solve those issues , are usually different , and I love to learn from fellow fire safety engineers because this gives me inspiration and breadth of knowledge that helps me solve my own issues , and that's the idea for inviting more fire safety engineers into the podcast and finding topics that unite us , topics

that are challenging worldwide and that we all have to figure out together . One of such topics is fire safety of car parks . In relation to the electric vehicle hazards , a few months ago we had a phase two report from NFPA on modern vehicle hazards .

We had a lot of research , some papers published over the last two , three years that shed new life into the problem of fire safety of electric vehicles .

I had brilliant guests in the podcast , such as Professor Peter Sturm , who's burned electric vehicles in a tunnel , and I can probably say we have also participated in some experiments on electric vehicles , which will reach the daylight in some time I hope sooner than later .

So I clearly see the knowledge base is growing and I also feel that the focus moves away from electric vehicles more towards scooters , which obviously seem to be more immediate hazard to tackle by the fire safety engineering community , or perhaps energy storage , which also is very , very interesting .

Nowadays I think I see that electric vehicles and hazards related to them became some sort of a normal thing in the modern world of fire safety engineering , which is great . That's a sign that the field is maturing , that we have more solutions to work with , that we have gained enough experience to handle those topics .

Just as another topic and yeah , this is what I want to extract from my guests I've invited two colleagues from Torrenton to Massetti . You've heard them previously in the podcast . One is Alia Shraffi , he's a principal , and the second one is Pavel Volker .

He's a senior principal and applied science practice co-leader at Torrenton Tomasetti , and they've been on a podcast talked about energy storage , and today I'm going to pick their brains on how do they approach issues with car parks which are supposed to store battery-powered vehicles . So I guess that's enough for an introduction .

Let's spin the intro and jump into the episode . Welcome to the Firesize Show . My name is Wojciech Wigrzynski and I will be your host . This podcast is brought to you in collaboration with OFR Consultants . Ofr is the UK's leading fire risk consultancy .

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Get in touch at ofrconsultantscom . Hello everybody , I am joined today by Ali Ashrafi . Hey Ali , good to have you back in the podcast . Absolutely , love to be back . And once again , paweł Woli hey Ali , good to have you back in the podcast . Absolutely , love to be back . And once again , paweł Wolka , hello Paweł , hi Bartek , great to be here again .

Welcome back to the podcast , guys . And the last time we were talking about energy storage facilities , and today I'm going to pull you further on the topic of electrifying our buildings . And then this time we'll be talking about electric vehicles , something that everyone in the fire science community loves .

We , I guess , learned to live with them so far , but it's not that we have solved the challenges in the design and , of course , everyone tries to deal with them the best they can . So let's give people some ideas and solutions and let's talk it over . I'm really happy to do that . For a starting point , what's the situation in the US ?

How does it grow the EV market and , let's say , the knowledge of the designers and how to include them in their design ? Looking back , I don't know 2016 , 17 , 19, . Do you see big differences how we approach those today ?

So it will pick back up and then the electrification of transportation will proceed along the lines of EVs specifically and then for the longer range heavy haul vehicles it's probably going to be hydrogen drivencar parking in a variety of urban areas , especially urban areas , in parking garages that are basically multi-car park storage facilities .

So that's one aspect that we see a lot of and the other one has to do with stationary energy storage type that basically supports grid , so it's not EV-related .

Obviously these are , like I said , stationary energy storage systems , but there's a lot of those in and around large urban areas as well and they present similar challenges of course more energy , similar density , but more energy basically located in one place .

As you know , in the US , everywhere , codes are usually slow to catch up to evolving technology right , and the same is true in the US , and so I don't think the codes have changed as much as the questions and the nature of things that clients ask us and we look at in a design context .

So if you're looking at prescriptive code requirements , there hasn't been as much change as when we look at it from an engineering perspective and try to come up with actual engineering-based solutions .

Did you have the same feeling that the problem was very like medial emotional some years ago and now have changed into much more technical discourse , or is it still something you observe in US ?

There's a need for a solution , okay , and you know , I guess that may be a characteristic of the way US economy operates where there's a need for a solution , a solution gets developed and people are very pragmatic about it . So I don't really feel that the discussion was all that emotional . It is certainly practical right now and focused on solutions .

I don't know that there is a sufficient awareness yet of the cost of these solutions or basically the types of the problems that we're dealing with , the nature of the problems , the nature of the hazard and then the cost of developing solutions .

I think there's an appreciation that the solutions are passable and that's increasing , but I think that the appreciation of the cost associated with it is lacking a little bit behind .

Certainly there's a lot more data out there so you can have a much more informed and detailed conversation .

I mean , if you have a fire , having half a million electric vehicles in the US , that feels completely different than when we have a fire in Poland , or we see a fire and we have 50 of them or 100 or 1000 , even . You know , I see that this perhaps was the driver .

And to understand the infrastructure multi-car park storage facilities , how they are built in the US Are they typically separate structures ? Are they built as a part of other developments , underground , overground , all of above ?

Basically , obviously , the ones that exist that are underground and not ventilated are the most challenging , but a lot of it , as to going into the solutions , or even the desire or the need for solution , goes back to who owns them .

What is the sort of risk profile of that particular owner or risk appetite of that particular owner vis-a-vis code requirements , which don't necessarily impose on you any strict demands as to what you should do . So some owners will choose not to do anything because they don't have to .

But , like I said , as far as the types that you're seeing , you've got everything that you've mentioned as far as coming up , and the new ones obviously create a bit of a more opportunity to address the issue up front , as Ali mentioned earlier , to apply a holistic sort of viewpoint to the solution and design them with the hazard in mind , as opposed to do sort

of a mitigation after the fact . But the existing ones are calm online , so to speak sooner or later , simply because of the progressing fleet electrification .

If you go in dense urban areas , of course you don't have that space , and then it becomes a mixed-use building that has a parking space and then you have a building above that .

For example , in Poland we have new technical regulations for buildings that define how much electrical power has to be connected to a new development , how many charging points you shall have per X number of spots , and so on .

So in that case , like requiring to design with EVs in mind already came here , but , as you said , the fire considerations are not yet part of that . So we've already our law already includes for EVs , just not for the risk management of the EV fires .

So , again , there's probably a bit of a lighter touch in terms of mandating things for a number of specific EV-capable spots , so to speak , but they do exist .

As opposed to if you want to be more performance-based and say , consider these things in design , you can , you have more room , but the US system is starting from a point of prescriptive . So you can do performance-based design but compared to the US , it's a lot more prescriptive design as a starting point .

What changes when you bring EVs into your mix of vehicles in your parking space ? So perhaps you could try outlining the differences . Well , that's a hard one .

We basically know what we're dealing with because we've been dealing with this for more than decades it's hundreds of years . At this point , obviously , evs are new and they create tremendous advantage from the point of view of simplicity of the vehicle built and construction .

But to outline the hazards , with highlighting the points of departure , so to speak , from internal combustion engine , you obviously have a fire hazard in EV just as much as you do in an internal combustion engine .

You also have an explosive hazard which technically could exist in an internal combustion engine vehicle , but it's basically taken care of as in it has been addressed through those safety features . And then you've got toxicity hazard in EV , which is also unique . So I would say explosive hazard and toxicity hazard are new to EVs .

And going back to the fire , there's just sort of a binary description of fire . The fires are different , as we all know , so it may look if you look at the heat release rate .

The internal combustion engine and EV look similar and you know , in both cases most of the fuel for the fire is actually given by the internals of the vehicle plastics and things like that as opposed to the actual powertrain fuel , be it gasoline or energy stored in batteries . But it's how that combustion chemistry actually progresses .

That's where the differences are . So I would say there's a significant difference in the fire hazard between ICE and EV , and then there's explosion and toxicity in EV , which is unique to those types of vehicles .

They come and isolate the risk and they might let it burn . It's actually a better solution , but it's not a big game changer .

I think the one place where you have more of these cars close to each other not on the risk side yet , but just on the hazard side the hazard which depends on how the fire propagates from one car to multiple cars does also depend on what we do in design and what the response to it is .

So , for example , if you have a situation where there's a protocol and there's accidents and the fire department can come in and control that much more easily , or you've detected it faster , you can act on the hazard in a way that mitigates as much faster than if you don't have those situations .

So that's a place where the hazard side is not given and then we're trying to just come up with a solution . The hazard also depends on what the response to it is .

That , the the energy , is a relevant question because , like , like I said , the bulk of the energy that is provided to the fire is internal elements , plastics and things like that . So the energy is going to look similar .

So what we found in our research is that , looking over all the published data you can find on the internet , when people test those electric vehicles the focus is obviously towards battery , because that's the interesting part , right .

So they go very heavy abused ignition sources like nailed through the battery as the ignition , or just two megawatt heptane fire underneath the car , which I don't think is a very realistic scenario .

So the way how the tests are carried are very battery ignition oriented , whereas in the same , let's say , decade , the last 10 , 15 years , when we saw tests of internal combustion engine vehicles , we've seen more attempts of ignition , like through the tire or through the interior .

So I shared your opinion , pavel , that the numbers look similar or ballpark , they are near to each other .

But I also see some artifacts of the way how we test and also the trends , like we're testing more and more electric vehicles because this gets you published , you know , this is the interesting part and less and less tests of internal combustion vehicles , and both types of vehicles get heavier , which means more plastics , exactly , yeah , so also , you know , comparing

2020 ev to a 2005 internal combustion vehicle , if you take battery away , if you take petrol tank away , there could be like 200 kilograms of plastic difference , which is significant .

So that's one aspect that confirms what you said as well . That came up in some of our reviews , literature reviews . The other element that's interesting is there's a significant amount of noise , like you said , in the data right , because a lot of people test it with a specific objective and you get that objective .

You don't necessarily get a full picture and the fact that there's still a limited amount of data that exists , especially of controlled tests , which I'll get to in a second , creates this uncertainty , significant uncertainty .

The tests are not very well repeatable , because if you test the system like a car the entire system then you don't really have a fully controlled environment the entire system then you don't really have a fully controlled environment .

You can control certain environments , but you really need to get into an element level or subsystem level to fully control the environment and have repeatability in the test , and that is currently lacking , because everybody's , like you said , very excited about testing the system and you know there's just too many parameters to control to make it a repeatable test , right

, so it just doesn't really help . That said , you know , kind of separating the power train , separating the battery itself and then the fuel tank in the internal combustion engine .

There are studies that go back to the 60s of both vehicles and buses that basically give you the idea of what the energy release is going to be in the fire of a bus or a vehicle , without consideration of the fuel itself , just burning the internals , burning the tires , burning the internals .

So we have an estimate of those kinds of things , a variety of different vehicles , based on old tests , and those are fairly consistent , right , because you remove the most uncertain element , which in this case is a battery , and you have a picture basically of what it is .

And based on those sort of comparisons , we obviously try to do , I'm going to say , a comparative analysis . Right , because it's not an additive analysis , it's not superposition .

Obviously it doesn't work over here , but when you start quote unquote adding those elements , the fire of the internal elements of the vehicle , whatever the type of vehicle you're talking about and its energy release rate and again , in addition to I'm going to say in addition to use loosely here in quotation marks to what the energy is of the fire within the

battery , fire off the battery , in comparison to internal combustion engine . And that's where my statement comes from in terms of saying that the majority of the energy is actually coming from the internals of the car , I would say significantly in comparison to the energy that's coming from a burning battery .

So there are a lot of similar themes between vehicles , whether they're electric or not , and some of them are , as we talked about . The cars have just gotten larger , more plastic to burn . They're larger , so now they're like when they're parked next to each other they're actually closer to each other . So it impacts propagation , for example . Right , so big picture .

When we look at all the variety in the data that you get because of just the changes in the size of the cars , the amount of fuel that you might have , how the ignition will start , whether it's EV or not in each of them , and you look at all of that , evs and combustion engine cars end up being in the same ballpark when you're looking at them as an

individual car . So it's really when you're looking at a system and inside an enclosed area where you start to see the difference .

They're not driven and nfp admits that by ev consideration , ev or battery fire consideration specifically , and then that's not . Again they get nfp . The problem is difficult and they're trying as best they can .

Is this also affecting your procedures , this different fleet that you have in the US ?

And you know we obviously , when we run analyses like this , dtap analyses like this , like these , we don't focus on a vehicle but we usually look at the range , we look at the traffic data within this location and then basically determine the offending vehicle as a source and the offending vehicle has to do with the whole thing .

So basically , the body that it has , the amount of energy that it stores and then in its internal plastics that add , to add the fuel to the fire , basically I had to ask about a huge american vehicle .

beast . Okay , the , the heat release rates , let's say , are similar , but there are nuances as well . So since the beginning of the ev considerations , we were worried about the jet flames from the EVs . This , from my perspective , have different kinetics in two ways .

In one way , you shoot fire for a larger distance , but also the fire has higher velocity , which impacts the conductive heat transfer . And from the smoke control perspective , that's also completely different entrainment than the buoyant smoke pools that we are used to as smoke control engineers .

So are those details , or those are important things for your considerations ?

I'll just talk a little bit about this in a second , because we're looking at it from two different viewpoints , I think as far as jetting , but also , you know , the peak release rate tends to be higher and it can cause very local , very intense for more short-lived but very intense impingement on structural elements and that can cause , in some cases , concrete

spalling , for example , exposing but very local right .

It's not a point point , but yes , it's local , but that can propagate because there's several different things that can happen inside a concrete mix , both from the point of view of the vapor pressure that goes inside , but also thermal expansion and the shear stresses it can cause at the layer that is basically that has a high gradient , thermal gradient inside of it

and where the cage sits , reinforcing cage . So there's a lot of different details and if you neglect them completely you might basically miss the picture , because if they fall , even what we could consider again , quote unquote point can propagate across the large surface area of a slab and that can cause a significant damage structural . So that's one aspect .

So that is an important detail . Jetting , obviously , is very important as well , because if it is somewhat high pressure , I'm not going to call it high , high pressure because it tends not to be excessive . We're not talking about supersonic pipe flow , you know , like we know in the natural gas world , but it is high pressure .

It can be high pressure jetting and it's directional and that can contribute to fire spread , fire propagation , because you don't necessarily have to propagate battery to battery , right If the battery starts the fire and then you have a directional flame that impinges on the tires of the adjacent vehicles , it will go , and it doesn't really matter that the battery of

the adjacent vehicle will go . Later it will start with plastics in the car . The fire doesn't care . The nice quote-unquote , very quote-unquote , nice or the easier thing about it is when it spreads like this , you're avoiding explosion . The fuel that's released is burning . You already have a fire . It will burn . It's unlikely that it will accumulate before ignition .

That of course assumes that you've got a certain layout or an open layout of the parking garage . If you've created pockets , individual pockets , so to speak , that can allow gas accumulation , even though in the adjacent pocket , so to speak , or the area you could burn , then you may have both , or the area you could burn , then you may have both .

So a lot of it depends on the details . But under the assumption that you have an open space and several vehicles parked next to each other , the fire spread basically fuels the fire , but the explosion issue is somewhat secondary at that point .

Once you get past a small fire , right , if you have a fire that engage multiple cars at some point , it becomes a very hard thing to deal with , right ? So really a lot of the question is making sure that if you have a hazard thing to deal with , right .

So really a lot of the question is making sure that if you have a hazard , it's a hazard that doesn't spread fast and large enough to a point where you can't control it but going back to my reality and this kind of hysteria that happened in the media is also not that a battery will immediately trigger another battery and another and another .

They've burned , but there was no thermal runaway in any of the secondary vehicles . They went through a significant fire yet there was no thermal runaway of the battery . So it's not that you subject battery to a jet flame and then immediately you'll have another jet flame from another . It's not that dramatic .

The cascade Also , you know , whenever I talk with fire scientists and at this point we also have experience of our own actually setting those batteries on fire just with an external heat source is not that easy . It's a very interesting point .

If you take a module not even a pack , but a module , multiple cells and you test it under nominally the same condition in the lab environment multiple times , you're not going to get the same result . Sometimes some batteries will be easier to trigger than others and sometimes the same battery will be relatively easily triggered in one test .

The same battery will be relatively easily triggered in one test and then you basically try to replicate that test , but with nominally the same battery or the same type of battery . Obviously you're not going to use the same one , but basically nominally the same battery in the same environment and you will trigger it .

So there's significant uncertainty related to this .

We just don't understand enough about the mechanism of initiation of thermal runaway within the individual cell , sweeping conclusions and and that's a pretty important piece from the point of view of fundamental research as far as the understanding well , I think we we have a perfect grasp of what happens when you nail them , you know .

And also , you know , going back to these artifacts of testing , it's very difficult to distinguish the natural growth and development of these events versus the trigger , because if I have two megawatts of heptane and I accelerate this , I don't even know how much I've accelerated , you know .

And then , taking the number from this experiment to my design , am I conservative or am I just wrong ? I don't know that right .

That changes because the chemistry changes , the amount of oxygen you have , the phosphates you've got , a different amount of oxygen than in other chemistry Solid states , how they evolve , use of supercapacitors in addition to the solid state battery there's a constant evolution of these things and they cause changes in the way those batteries react .

But I mean , at the end of the day it's an electrochemical cell . We're dealing with an unstable or conditionally stable system . The energy does not want to sit there , so it will get out under the right conditions .

We don't even know what's happening in the R&D labs of those big manufacturers . We have no clue . What are the next generation separators , electrolyzers ? We'll not know . It's very difficult to obtain that knowledge , but yet I need to design my car park today . You know that's going to stand there for 50 years .

What do I do in the in this uncertain reality ?

So in the first instance , if you're affecting likelihood or probability of occurrence of an event in this case let's just say thermal runaway then you would basically take certain actions that would reduce the probability of occurrence . We do not have that ability at present .

But you know , specifically to your question and that's the world we operate in you come at a problem from the viewpoint of a car park manufacturer or an owner and if you own a car park or are building a car park , you don't get to necessarily choose which vehicle you're allowing to park and you're not going to make a call to a car manufacturer and ask about

the details of their battery and the safety system or their battery management system , for example . And if you were to do this , you're not going to get any answers right .

So you operate in a bit of a dark space as far as the probability of occurrence and you also have even less influence on limiting that or reducing the probability by certain active measures , as in , you know , basically prevention .

So in what we do , for the most part and there are some exceptions to it and I can't really get into the details , but some of it is government-sponsored research .

So , with the exception of those , if you're talking about a commercial world , we are assuming that the event will happen in a vehicle and you focus on the other side of the risk , which is consequence . We know the consequence is high . So how high is it ? What does it really mean and how do you mitigate the consequence ?

So you basically are saying we understand that as an owner of a facility like this , you've got limited at best , at worst zero influence on the probability of occurrence , and reducing that . All of your influence sits in understanding and managing the consequences of the event , and that's where we , a majority of our focus , really is .

As Pavel said , we can look at it and take a range for that uncertainty but say what are the things we could do on the consequence side to make the design better compared to baseline , where we were not going to do those things right . And so you can certainly show that you're making an improvement , understanding that none of what we do is targeting zero risk .

That doesn't exist . Right . For everything else that we do for designing buildings for earthquakes and wind and flooding and all that it comes with a specific chance that things could happen that are more than that , and the same is true for any fire-related scenario .

Dissemination of that knowledge will accelerate over the next three to five years , I think . So that creates a bit of an opportunity because as practical solutions are being implemented , that knowledge again dissemination will accelerate further because people will basically use it as a precedent . So that's one aspect . And then there's a question of cost right .

Those solutions will remain costly as they disseminate . They will remain costly , which will force the issue of more and more fundamental understanding on the probability of occurrence . Would it be cheaper to prevent it from happening in the first place than mitigating the consequence ?

And I think that will over the next again , three to five years , maybe a little bit longer . We will see that change a little bit and the shiftID onset and whatever happens later . I'm done .

It's not going to bring the building down or a car park down Highly unlikely unless something else was done Not quite

right . So limiting the spread is the name of the game when it comes to fire . From that point of view , even if two vehicles were to burn , that's okay and there's no number , I guess that you could throw an absolute and say that would be okay . It all depends on the circumstances where those cars are .

But you could manage individual vehicle or individual vehicles on fire , evs and obviously once the fire starts spreading , it doesn't discriminate , it doesn't care if it's internal combustion engine or ev next to it , as long as you limit the spread . That's probably the single most important thing from the point of view of fire .

Like people would like to install them because of this new hazard , even though we may agree that from the heat release rate or total energy release , it's all . Park similar separation distances , but that's very difficult . We want to pack as many as we can to car parks . I like playing with the heights of the ceiling because I feel there's a huge value in .

Yeah , very important , very important . And we saw that we just burned the car during the summer school and the ceiling was at three meters . You could see like , once the fire hit the ceiling , you could see how it went quickly . You know , I strongly believe it is a huge variable Walls , opening factors , whatever else comes to your mind .

How do you realistically affect or decrease the probability that fire will spread between vehicles or and , in consequence , you're going to limit the consequences of the ?

The challenge with these , especially the more permanent barriers or rigid barriers , is that you may exacerbate the issue of explosion . You may exacerbate the issue of explosion Because those elements that separate the fire , especially the rigid ones , will likely allow accumulation of the flammable gases if it is released from a battery without being ignited .

So that's a very , very important consideration that's often lost in the discussion . And the other thing and that goes , I guess , around moving into the explosion aspect , once you start releasing the gases and you ignite a flammable gas cloud that is accumulated in a particular space .

And those things are really important too in terms of what the consequences are .

So if you think about these early in the design so the EVs are not an afterthought , but you know you're going to have a certain number and you can start looking at how am I laying them out and how close are they to openings and how easy is it for the fire department to come in ?

And can I protect people to be able to evacuate if needed in a way that gives them time and they're exposed to less risk ? And all those things really do drive the consequences . They drive the strategies on how to fight the event , both the explosion and the fire side of it .

So when you're looking at eViz , it's best to look at it as something that can inform all of the design and have that conversation early on and have that holistic design , and then you can converge to a solution , that's a much better solution and it's a much cheaper solution as opposed to coming to it at the end and most of your design is set and now your

options are

much more limited .

So confinement speaks to inability of burning gases or hot gases to expand , and when you prevent that expansion from happening , you've got pressure rise basically . So that's one element . And then anything that changes the flame speed . If you throw a lot of congestion into it , the flame speed , hence the flame itself , the flame front tends to change its shape .

You've got a bigger surface of heat transfer and you start accelerating the flame front . And you can in the case of hydrogen , that's a known fact you can basically turn deflagration into detonation . Ev of gas is 35% , roughly hydrogen . It's a mix , obviously . So you're dealing with a much more complicated gas mix from the combustion chemistry point of view .

But you know there's no research right now that says you will not change that . You will not transition from deflagration into detonation and , given the high hydrogen content and its characteristic , that's something to look at .

And even if you don't change , if you don't basically end up with a detonation , congestion or any element that will accelerate the flame front will lead to significant increase of overpressure .

Between fire and explosion there's that trade-off where sometimes you do something that makes fire better and explosion worse , or vice versa , which means when you're trying to come up with the right solution , it's the right solution in the context of a specific building . It's not the right solution everywhere .

It's the right solution for that building in that particular condition , with those sets of TVs in those places .

A lot of them are based on particle permillion , basically the gas particles that are in the air . Some of them are focused on temperature , some of them are focused on pressure . There's a whole suite of different sensors that allow you to do this and I'm going to say allow with again another one of those quotation air quotes , so to speak .

We're not aware of a single silver bullet over here , but it is a critical element , as you've pointed to , wojtek , in terms of you know , when you kind of trigger , obviously one answer would be to say , okay , in a highly critical space you might just run your active ventilation system all the time , but then it becomes incredibly costly .

But you know , I only mentioned that to highlight that active ventilation system and we're not talking about insignificant rate of error changes , right , it's a significant amount depending on the details that you would have to exchange per hour to make a problem go away , but it is doable , it is possible to basically make the problem go away .

So and I specifically mentioned that in the context of , let's just say , you have a relatively small room within the building . You're not talking about any e-parking , but you're talking about scooters and bikes , e-bikes and e-scooters in a relatively , again , small room that is fully enclosed . So a potentially bad scenario .

You can design a ventilation system that will exhaust all of the gases from this thing before any explosions can occur , and this is not , again , an expensive solution , but not a practical solution in terms of even running that system all the time , so that you don't basically get any gas , flammable gas , accumulation in there .

Propane is also heavier than air , so it spreads on the floor , not underneath the ceiling . So I kind of find a lot of similarity between those hazards that we've already learned to deal with , at least in Poland , in terms of LPG-fueled cars , and potential explosion challenges brought by the world of electric vehicles .

Do you know how common it is that the thermal runaway gases do not ignite and form this hazardous cloud ? Do we have a ballpark number ?

Because if you take hydrogen flammability range , then okay , it's just not only super wide , but also you have very low ignition energy , right ? So , like the worst of the worst , and if , in the same time , you assume that all of it goes up , as it would with hydrogen , then that may be an unconservative assumption , right ?

Because , like you said , some of the gases will actually sit there a little bit lower , some of them will actually spread around floor area .

So you have to figure out a best way and run basically a bit of a parametric study to figure out what your design parameters really are , because you don't want to compound conservatisms and you also don't want to be unconservative . So that's part of the reason why we exist in the risk world when it comes to those considerations .

Right , it's very risk-driven design . You have to consider the scenarios that you have . Do first , pass at the risk scoring , quantitative risk scoring , you know . Sharpen the pencil on the highest one . Sharpen the pencil once again and iterate on those things before you actually say , okay , this is my environment that I'm dealing with and start designing .

So these things are important and I didn't expect us necessarily to get into the weeds of that , but we are Super interesting .

But it also highlights why it's a difficult problem and also why authorities having jurisdiction having a tough time regulating this thing , especially in the space where people kind of expect a bit of a standardized approach where you do one , two and three and case is closed . It won't be that for a long , long time .

Do you have any examples of how thinking about it too late was problematic from the design point of view ?

?

You've designed your infrastructure , you've designed your chargers and now you come in and you want to quantify that because you thought it's not going to have an impact .

And then we run our analysis and it's a detailed analysis and we want to move some up , for the cars are to be able to come up with a reasonable cost solution , right , where you can balance the explosion and the fire risk at the same time , right .

And that ends up needing you to change the number of EVs that you have and change your location and change your design of your charging system . And if you're really being looking at all of it , it might really affect where you have people coming in and out of that space , and those are very hard to like . If that comes towards the end of the design process .

You either do all those things , and it ends up being very expensive , or you're not doing them , and so now you either have like a more expensive solution or you're living with what you have Right . So that's what I'm talking about Like the later you come in , the less things you can play with to come up with a good solution , with an optimal solution .

Okay , and the process is such that you require placement of certain critical elements , including potentially vehicles or stationary energy storage systems , in a certain location , and it may be driven by I don't know the cost of the counter wire . It may be driven by latency of the transfer .

It may be driven by the reliability requirements there could be a lot of stuff that kind of or just transport requirements if it's vehicles , right , If it's anything that sort of . There's an overarching objective of a specific facility that requires that you place energy storage systems within vehicles or not , stationary , within specific location .

That becomes difficult , especially if that process was already designed and you come in to sort of mitigate the risk . That becomes very difficult and very costly , becomes very difficult and very costly .

The flip side of it is that if that process is important enough , it requires that sort of solution , then the cost is easier to absorb within those types of projects than commercial facilities that simply rely on parking .

When there is a burning need pun intended , really a burning need for solutions , then solutions do evolve .

And I think that there is a tendency for big institutions I'm not going to say big institutional clients , institutions who have a stake in what they're doing , not just from the point of view of protecting their assets , but also from the point of view of their reputation that they put on the line to implement solutions that are forward thinking , visionary , and they

do that . And we see an increased tendency to do this , to do the responsible thing . Here in the US , we see it all the time .

And when those solutions are implemented , a lot of people tend to copy those and it's very difficult to argue that you didn't do what you needed to do if you copied somebody else's solution who basically , you know , studied it at length , did the proper risk assessment and implemented a set of solutions .

So once you have enough examples out there where you could basically travel from facility to facility and observe what was done , including the ones who may have undergone a situation in which an EV burned or there was an explosion , and how the systems handled that type of thing , which you know . It's inevitable , unfortunately , that we will see things like that .

I think solutions will start propagating and I don't think that to your point , I don't think the understanding is going to be completely there . I think we'll always have , from the scientific and engineering point of view , a lot of questions on this .

Maybe not always , but for foreseeable future , for the next 10 years , given the evolution of things , I think there will be a lot of unanswered questions , things .

I think there will be a lot of unanswered questions , but I think that , just as it is in the real world , the engineering solutions are all about making sure that we focus on what really matters in the grand scheme of things and design such that we oftentimes avoid the hardest problems by basically eliminating them .

And I think we will get to that type of stage within the next 10 years where we'll be able to basically design the problem away , so to speak , because we've seen a number of different solutions , We've seen how they work and we've seen enough studies on that .

But once we have enough of them then it will be easier to say this is when you use template one and this is when you use template two .

I just stopped it and I just , oh my God , this looks like a megawatt . So what if I started my simulation immediately with a megawatt , like what it would look like , and I wake up in the morning to see the results and I'm , oh my God , we're not ready for that ?

That was an immediate like a feeling of overwhelm when I saw this scenario six or seven years ago . But fast forward seven years . I believe we're at the point where we can calmly approach it , distill the differences , identify the sets of challenges , propose solutions .

Perhaps , pavel , what you say , seven , 10 years , maybe it will be just , you know , run of the mill , typical building A , apply these rules and they just work . And perhaps we'll , most likely we'll have to deal with specific challenges brought by new vehicles of the time .

I'm pretty sure that the industry will provide us with new , uh fun challenges to solve , but uh yeah , yeah , just I'll be .

Okay , it's a thing we're going to address it . This is how it's going and it's not going to be a research project , and right now it isn't really a research project . It has elements of research project . It's going to be part of the design , I think , and I think we will see that within the next 7 to 10 years .

But well , if we only can deal with consequences right now , let's hope we will have some really , really decent tools to deal with those consequences in seven to 10 years . I believe we do have those tools today . It's just about the trust and about how easy they are to apply .

A lot of ideas were given in the podcast episode , so I hope that was a good foot for thought for you to create your own solutions for your electric vehicle car parks . A lot of new things were brought up , especially the risk of explosion .

We actually had an explosion , most likely related to lithium-ion batteries , in Poland a few weeks ago in which two firefighters have died A really tragic story .

It was not in a car park , but in a basement level of a building , so clearly the understanding of how great the explosion hazard could be with lithium-ion batteries is growing and it's not looking pretty , so we definitely need to find solutions for that .

One thing that , from this discussion , is a little bit scary to me is that fire is at least we know what's happening and we can deal with that , whereas when you have a vapor cloud and it explodes , it's challenging . You have to detect it . To act , you have to use some specific features like ventilation . To reduce the concentrations .

There is a different set of tool and reactions . To reduce the concentrations , there is a different set of tool and reactions , and I believe we need to approach the fire and explosion safety together holistically , otherwise it's not going to work .

And also what Ali has said I think that resonates with me super well is that you need to think about those electric vehicles or those hazards trade when you start designing .

If you think about them as an afterthought , that's going to be very , very bad and very challenging to actually introduce safety features into your building that will work , that will be cost effective , that will solve the problem . The later you start thinking about it , the harder it's going to be , and I assume the hardest will be when you're refurbishing .

That must be very , very challenging . And if some of you have good ideas how to retrofit electric vehicles into existing car parks . Let me know . Perhaps we can talk on the podcast , because I think that would be interesting subject for the future . For today , that would be all .

Thank you very much for being here with me and see you here in the Fire Science Show the next Wednesday . Cheers , bye , bye .