112 - Fire Safety for Energy Storage Systems with Ali Ashrafi and Paweł Woelke

Fire Safety for Energy Storage Importance

Wojciech Węgrzyński 0:00

Hello everybody , welcome to the Fire Science Show . Today we're again touching the subject of fire safety , of energy storage and battery devices . These times threw the eyes of fire safety engineers and we're going to talk how to implement real life solutions for this type of storage . I have invited two gentlemen from Fallon Tomassetti . First is , who was the previous guest on the show almost 100 episodes ago . You may remember him from episode the Bald Resilient Design for Firefighters Safety , where we've discussed how the battleground changes and we're kind of coming back to the subject again today . The second guest is Pawe Volker , also from the same company . Both of them are involved in designing fire safety for different types of energy storage devices for buildings that have to include , for example , energy , new energy carriers , electric vehicles and stuff like that , which seems to be kind of mainstream for fire safety engineers today . So I guess this will be interesting for you to hear what fellow engineers have to say about how they deal with the projects everyone of us is already facing or will be facing in a near future . I hope you will enjoy this one , so let's spin the intro and jump into the episode .

Wojciech Węgrzyński 1:23

Welcome to the . My name and I will be your host . And , as usual , please give me a second to appreciate the role of the sponsor of this show , ofr Consultants . Ofr Consultants are a multi-world winning , independent consultancy dedicated to addressing fire safety challenges . Ofr is the UK's leading fire risk consultancy . Its globally established team has developed reputation for preeminent fire engineering expertise , with colleagues working across the world to help protect people , property and environment . Recent growth has seen it continue to build on its globally established reputation , advancing its journey to net zero , including embarking upon a carbon balancing journey with the world and trust and recruiting more of the fire sector's best talent , with the team now in excess of 100 professionals . In 2023 , ofr will grow its team once more and is keen to hear from industry professionals who want to collaborate on fire safety futures this year . Get in touch at OFRconsultantscom . And now let's learn about how to protect batteries from fire . Still talking about the battlefield and how it's changing today 100 episodes and not much has changed and , paweł , welcome to the podcast .

Wojciech Węgrzyński 3:11

Thanks for a month , thanks for having me , thanks , guys . And as I told you privately before we started and I'm now going to share with the audience , there was a lot of battery episodes in Fire Science Show and they're all very popular and that's very important to engineers around the world and I've been so far interviewing mostly scientists on the subject and for this podcast episode I thought I need to have some real engineers with skills and experience on this field on the ground to give them all a relatable view on the subject . I really want to understand the engineers perspective and I'm pretty sure you guys can provide me with that . So , to start with Ali , in your emails you've drawn a very nice context of the whole energy transition system as a part of a bigger transition that we need on our world in all . So let's start with that . So let's ask ourselves why are we dealing with the battery problem instead of just banning them and living our lives on ?

Ali Ashrafi 4:11

Sure , so I'll give a quick introduction and then Paul can expand more on how it really fits . But basically we're in a world where climate change is a major driver of a lot of hazards and risk for us . Right , so we have in the US , but globally we are seeing wildfires that are happening much more frequently and much more intensely every year , and that's a lot of risk to human life and to our built environment and in our society . We're seeing hurricanes that are happening strongly and more strongly and more frequently . We have the challenge to food safety . The climate has significant geopolitical impacts . We both live in New York , and last week , or I guess two weeks ago , new York City was black because of this , more coming from wildfires from Canada , and this is something that California experienced and other places to write .

Ali Ashrafi 5:08

So we are in a context where we have very large macro scale risks to human society , including risks to life , and so part of that response is we need to move towards renewable energies , and when you look at that , whether it's wind or solar , for example , when and where you're producing that is different from when and where you're going to be using that Right , and so to fill that gap , we have multiple elements , including massive amounts of energy storage . So when you're looking at the context of energy storage , it's not an abstract . It's coming in the context of we're dealing with this very global challenge to our society , including life safety risks and food safety risks , risk to our financial system , and so that's where energy storage comes in . Paul will can give a much , much better description of the elements of that system . Please go on .

Paweł Woelke 6:05

Yeah , so not to be repetitive , but I think it's useful to state a couple of basic facts . Climate change is a fact . We are all working towards the Paris Agreement goals , so that these are 2015 goals one and a half degree above pre-industrial levels . Now reaching those goals requires deep decarbonization of the entire world economy . You can't decarbonize world economy without looking at the energy flow , because energy flow energy in general is both supply and demand sectors are responsible for about 90 to 95 percent of global emissions . If you look at the energy both supply and demand sectors then , as Ali mentioned earlier , one of the key elements of the energy transition is related to renewable energy sources , replacing fossil fuels with renewable energy sources . Those are incredibly efficient about 95 percent , depending on which piece you pick . It also cleats . The problem is that they're intermittent , so you have to address the what's called peak shaving , and the two most effective ways of addressing this arguably are expansion of grid and ultra high voltage , long distance transfer of the power , and the second one is energy storage systems , the various ways in which you could store energy . Hydrogen is actually the most scalable from the point of view of energy density , but the most ubiquitous right now is lithium ion batteries and those could be grid supporting batteries that basically allow you to address the intermittency issues . So it's a key enabling element , element that enables the energy transition from point of view of both supply and demand sector Going into demand .

Paweł Woelke 7:43

You're talking about transportation , manufacturing and buildings . Transportation is leading the way and it's focusing primarily on electrification . There are various debates over that makes sense before the energy supply is decarbonized , but we'll talk to the cycle . That's a different topic , I guess . And electrifying transport means a huge expansion of electric vehicles . They're for lithium ion batteries that are entering and mass into the urban area . And when you start talking about safety aspects of lithium ion batteries , thermal runaway in the middle of nowhere is one issue . It's a significant issue , but it's a different issue than the thermal runaway of a series of vehicles happening sequentially as a cascading effect within the urban area , especially if it's densely populated area . So these elements are some of the key issues that we're focusing on Not to neglect the other two , to broadly the other two energy demand sectors , that's building and manufacturing .

Wojciech Węgrzyński 8:36

If I look at buildings , so we do have these energy storage systems . You said that , okay , you can have it in the middle of the desert next to a solar farm . That's okay . You can have the energy vehicles inside the city . That would be another , like a movable energy storage device . Wherever then the car stops , there's the storage . But also in the city you would have , to some extent , a smaller scale power banks for buildings , or people would be building power banks in their houses , or maybe even , perhaps even apartments . So can you tell me about this middle ground between them ?

Paweł Woelke 9:08

It's a very good point , you know , just parking , electrification of vehicles . For a second . We'll get back to buildings , because it's obviously tightly , tightly , tightly tied with buildings . If we talk about batteries that are used for let's just call it broadly energy management at the level of the building , anything that requires emergency power backup so think hospitals , think data centers , anything that uses diesel generators will likely be gradually replacing to energy Other systems that will serve as emergency power . Back Batteries would be the easiest way to solve that problem . Now that creates another issue , because those systems will have to be placed either inside the buildings , depending on where you are , or in close proximity , and that has to do with the amount of copper wire you're using . Cost related to this , efficiency and things like that .

Wojciech Węgrzyński 9:57

Or simply the fact you had a diesel generator in the building and you want to replace it . So exactly , the whole infrastructure is there and yeah , so from that point of view .

Paweł Woelke 10:06

There are obviously risks related to operating diesel generators , but these are fairly well defined and understood . If you replace that generator with battery , which is the right thing to do from the point of view of decarbonizing your building , your asset , you have to address the change in the risk profile and that is a significant challenge , simply related to the fact that this energy storage system is going to be bigger than , say , a single electric vehicle , any electric vehicle because it's supposed to manage the energy flow on the level of the building , or a much bigger asset . So , absolutely , as you've asked or as you've stated , these energy storage systems , whether it's lithium ion , batteries or other systems , entering the built world , built environment , in support of the energy management for those specific assets , is another key element that we're looking at and focus is going quite intense .

Ali Ashrafi 10:57

And , if I can add to that , in general codes do tend to follow the technology by some delay , right , if the technology gets developed and it takes time to figure out the solutions and put it in the code . But for technologies that are more mature , most of that has happened . In this context we're looking at something that's a very fast-changing technology . It's actually a family of technologies . We say these came on batteries , but looking at different chemistries and then how they're put together and the safety systems that go in them and then how the context of where you're using that . It is a very quickly changing problem . By definition , you are looking at the context where the codes are going to be playing catch-up , not just now . It's not the problem that's going to be fixed Next year . It is a problem that's going to be with us , which requires to move from cookie-cutter solutions which are not developed . It really requires looking at specific analysis and engineering to come up with solutions that are context-specific . So it's really moving towards performance-based design .

Wojciech Węgrzyński 12:06

By codes you mean like a specific NFPA standard for application , or you mean like IBC or New York requirements , or both of these .

Ali Ashrafi 12:16

All of the above Okay , because just the time , the speed of change in technology doesn't match the speed of development of the code . Again , in this particular area , it's a very complex problem . So coming up with solutions , the solutions will really vary depending on the context of the solution . So it is large-scale energy storage , is it movable energy storage , how many people you have Can you evaluate people or not ? Those are all factors that could impact what the solution looks like and all of those are hard to come up with a cookie-cutter solution for them in the context of this changing technology .

Wojciech Węgrzyński 12:56

I would take that further . So in a slow-paced world you would expect first some sort of laboratory standard for tests . So let's say UL develops a standard to test power banks or large batteries for purpose of using them in vehicles . Then this is adopted by somebody like NFPAs , who define that this is the certain way you use them and this is how you provide safety to them . And then let's say New York City Council says the law Okay , guys , just use UL-tested NFPA guidelines to deliver it safely .

Wojciech Węgrzyński 13:29

But today UL is working on their thing very rapidly . I know because I had Adam Barovin here who's in the middle of designing that and it's crazy how much work these guys have NFPAs developing their own standards as fast as they can , and I am very impressed by the speed they can actually do that compared to our European legislation . But still it's lagging behind the technology , like you said , because today we have different batteries than three years ago . And then you have your own city council . You have your own like IBC and other bodies who have to do the battlefield design and then don't have desiccers . So what sort of tools engineers have today to design with ? Because it feels kind of scattered , right .

Paweł Woelke 14:11

Yeah , I think that's a very interesting thread and I agree with your assessment as to the speed at which the various governing bodies are working and including UL from the point of view of testing , and part of the issue is just how complex the problem is and how much we know about it or not know about it because it's a new relation .

Wojciech Węgrzyński 14:30

I would just like to emphasize it's not a critique that they're slow . Yeah yeah , it's just the environment that we are in . You know , absolutely . It worked for 100 years , but it never was supposed to work with the technology that changes generation after generation in one year cycle . That's crazy , right .

Paweł Woelke 14:49

And even if you , for example , freeze the specific aspect

Risk Management in Technology Design

Paweł Woelke 14:54

of technology . So let's just say you use exactly the same chemistry of exactly the same battery and you test it 10 times , you're going to get a lot of different answers . I'm not going to say 10 different answers , ok . There's huge variability in the test outcomes . Repetibility of the test results is very , very small , and that's part of the issue . So , going back to your other question , what can we do ? So we have to use being informed by the test data that exists and , in the same time , address it from the point of view of not the worst case scenario .

Paweł Woelke 15:27

If we treated the way we've treated other problems , sort of in a deterministic way , that we identify the worst case scenario for any particular problem or any particular solution that we need to develop , then it's unlikely we're going to find an effective solution . If we , however , apply more of a probabilistic method and risk-based method , something that oil and gas industry and nuclear industry is very well versed in , then now we have a real shot of finding very effective solution to a problem , and that is specifically what we're doing . We're basically looking at it from the point of view of risk . Risk , just to be complete , is a product of probability of occurrence and its consequence . So you've got two separate levers that you get to play with . How do you limit or reduce the probability of occurrence and then , once it does occur which you have to assume it will what is the consequence and how you address that consequence or vulnerability in the case of structure , that's another term that's typically used for those .

Wojciech Węgrzyński 16:26

But in this approach you would also have the third part , which would be the acceptance , like where your acceptance is and how do you decide where to put it so right , so that typically that's managed on the level of risk .

Paweł Woelke 16:36

So you basically calculate the risk as the product of those two elements , so likelihood of probability of occurrence , times , consequence and then you basically quantify the risk in that fashion . And then you have to talk to the stakeholders . You have to engage the stakeholders , all the stakeholders , to define what the acceptable level of risk is . And so that's where the acceptance comes in . And it's a similar approach to other extreme loading cases like intentional attacks and things like that . Zero risk is not achievable . You have to define the line where that certain level of risk is acceptable , and that depends on the stakeholders and it's not uniform across jurisdictions owners , what have you ? Or the world ?

Wojciech Węgrzyński 17:19

So it would be some sort of consensus or discussion driven process to find the target and as soon as you agree with your client , you would then seek solutions on the side of the probability and on the side of the consequences , the consequence correct .

Ali Ashrafi 17:37

We've been talking about some of the things that are new about this . It's maybe important to also emphasize what hasn't changed . So what Talba was talking about is something that we do in other contexts of design , where , when we're designing buildings to be safe for earthquakes or for wind , we're designing given a small probability of something worse happening . Right , because you can't design for an infinite risk . You have to balance your risks against what you're doing , both for that building and with everything else . So , in the context of the building , you have a risk from earthquake , you have a risk from hurricane , you have a risk from fire . All those things should be roughly in line with each other , right , and even looking at it from a perspective of society , we don't use all our money to build buildings but not have anything on education or on food safety and all that right . We're trying to have a reasonable level of safety , and so what Paolo is talking about is fully in line with what we do in other contexts .

Ali Ashrafi 18:36

Sometimes , in fire , people are less used to the idea of explicitly defining what that level of hazard and risk is , but that's what we need to do in this context , right , but it's not different from what we do in other contexts . In terms of approval , too , we've always had new technologies come up right and codes do allow you to go through an approval process where you show what's happening and you have a discussion with the authority that has to approve that and give them the right level of comfort that what you're doing is safe and okay . It's just when technologies are developing slowly , it's time to educate and make people comfortable gradually along with that . Now we have to do that at a much larger scale , right , so we have to kind of have a large-scale discussion about in this context . We're going to do a lot of design that's going to be different from the past , using the same principles , and so their discussions will be much more context-specific and performance-based .

Finding Reliable Data for Battery Analysis

Wojciech Węgrzyński 19:36

What fuels your input for this analysis ? Let's say , let's focus on probability . For a second , like you rely on data provided by manufacturers of batteries , you rely on statistical data for , let's say , I don't know , a new acquired department . How does one , in this scarcity and chaos around , finds reliable data to work with , or the most reliable you can find ?

Paweł Woelke 20:01

Yeah , so that's a very good question . I mean , it's also a very difficult question . There's a simple answer and then the more difficult answer . The simple answer is that there's not enough data . We've got a lot of events , but every event can be classified as its own thing , because the battery is different , the age of the battery is different , the conditions it was subjected to is different , so it doesn't need to be fit into a category that you can use and mindful data .

Wojciech Węgrzyński 20:26

It's not like a cigarette to a couch type of a scenario .

Paweł Woelke 20:30

Yeah , and it's not like a seismic scenario , for example . You've got a return period , you've got data that you could basically lean on and define the probability of occurrence . So we're just getting into the element of the probability of occurrence based on the events that we're observing . So right now , to get more directly to the question that you posed , right now , if you're dealing with a significant element of energy storage system , specifically that you might embodies being housed inside a building or your asset , you have to assume that storm or runaway will occur . That's almost a certainty .

Wojciech Węgrzyński 21:03

So you would design , with probability of one , that at the life of this building setup there would be a signal Okay .

Paweł Woelke 21:13

And then there's a question of whether you want to and this goes back , then , to the overall risk matrix . Is okay , do you have one ? Do you have two ? Do you have three ? We are not currently working with the assumption that you would have independent , instantaneous thermal runaway and multiple energy storage system . In other words , only one .

Wojciech Węgrzyński 21:33

Sorry , pavel , but you would consider this as a thermal runaway of a cell , of a module , of a whole pack , or probability to each of those and no , so single cell goes into thermal runaway , that's one .

Paweł Woelke 21:46

And then , once you have a single cell going into thermal runaway , another assumption is that on the probability side is that you have to assume that it will propagate . It will cascade cell to cell inside the pack , so the whole pack is going basically is the assumption within the single vehicle . And then you start putting into okay , what are the fundamentals of what's happening ? Does it propagate ? And now you don't have to really play so much with probabilities based on existing data , you can now get into the science of what's actually happening , the fundamental physics and chemistry of what's happening .

Wojciech Węgrzyński 22:19

So in your design scenario the basic brick would be a pack , and how many cells are . How big is a pack ?

Paweł Woelke 22:26

It's usually thousands of cells . It depends on the size of the vehicle . Size of the vehicle , mostly in this case , size of the battery overall and it types of the cells right when it's a cylindrical powered cell , whatever it may be . So it varies greatly . Right now it's in the pace of development . We usually just work with the overall energy content . So you're talking , on the level of a car , 120 to 200 kilowatt hours . And then the other aspect of it is basically the data that exists of this type of a pack in terms of but here you'd consider the whole car battery as a single pack .

Wojciech Węgrzyński 23:03

so in this scenario the whole okay , the whole thing .

Paweł Woelke 23:06

Yeah , you don't really start from thinking about a single cell and try to assess that a thermal runaway in a single cell propagates to another cell and the rate at which it does where it stops , and all of that . That requires specific knowledge of the battery system , of the battery system design , and we don't have that knowledge . I mean , we could have that knowledge , but the point of view of a building owner ? They don't have that knowledge . The car pulls up and it's got what it's got .

Wojciech Węgrzyński 23:32

When I'm talking with my fellow colleague scientists , I often say like it's probably very difficult and perhaps even naive for a fire scientist to do the research on the battery . Fires like cell-to-cell propagation chemistry inside the battery , if you're outside of the industry . You have to do this research with the battery industry to be relevant , because if you rely on buying batteries from the market , you perhaps are quite lagging behind the current development of technologies , right ? So it's difficult to affect , as a fire scientist or engineer , the interior of the pack . Now , exterior of the pack . Yes , this is your regime , this is your building , this is where you can work . But you also have to understand the context of that was my next question how the context of the pack and chemistry influence outside the fire itself .

Ali Ashrafi 24:27

And Roy said , if I can add something to what Pavel was saying .

Ali Ashrafi 24:31

So just again putting it into context , it's what we do for other types of risks . Right , so you have a building , we do everything we can to minimize the risk of a fire starting , right , but we have a whole set of safety features that are based on the assumption of fire does happen and the fire is not the match . The fire is a decent-sized fire . How do you manage that , right ? So in this context we're looking at yes , you absolutely have to do all you can do on the battery manufacturer side and control side , and all that to minimize the risk of something happening . That's very important . Right , you reduce that probability . But from a perspective of a design of a building , whether you have people and facilities and assets , you have to make the assumption that something does go wrong . Right , and something goes wrong at a scale where it's meaningful to you , which is what Paolo is describing Then how can we try to mitigate the effects of that ? So it's the same general philosophy , but applied in this context .

Wojciech Węgrzyński 25:28

Yeah . So now let's go into the chemistry or the engineering of a battery pack , like how big a difference is in your approach when you're faced with , let's say , manganese batteries or iron phosphate batteries different chemistries that we know that have different energy densities . They have different , let's say , charging , discharging properties which affect how they heat up , how quickly they can heat up , and stuff like that . There are consequences that come from the simple chemistry of the battery the same in the module . If you have a module , you will have different filler between the cells that will affect the propagation . You will have different venting strategies , a lot of little elements that in the end can be a difference between a very hazardous designer or a potentially harmless design . To what extent engineers must understand it and take this into account designing this system . The building , yeah .

Paweł Woelke 26:20

Very good question again , just to pull back on the previous thread because I think it's interesting . Just on the scientist or academic research , there's always value and fundamental research Benefits detach and it's very often detached from the industrial application . But if it is insightful , let's just say which . We know that some papers are more so there , more insightful than others . But if it is insightful , you'll find something that fundamentally applies to the technology as it is , even if it weren't informed by the manufacturing . I just want to throw it out . I think that the medical research is always value . Thank you for that .

Paweł Woelke 26:55

Going back to your question , all of those things matter . Just as you said , these are just a little better from the point of view of the oxygen content less oxygen inside , less fueling of the fire , irrespective of what happens outside .

Fire Strategies for Energy Storage Buildings

Paweł Woelke 27:10

Design of the body , what are the barriers between cells , how are module structures ? All of the stuff that you've mentioned is very important . As an engineer , you should have knowledge . You should have as much knowledge as possible .

Paweł Woelke 27:24

The problem is you don't know any of this . You don't know what's pulling up . What you know is that there's a car pulling up and you can't design it for , say , one brand of a car versus the other , knowing that they have different chemistries used , because you don't control that . If you own the building and you've got a parking garage with chargers in there , the idea is that you service whatever comes . So you have to somehow pull it all together and take not necessarily the worst case scenario , the worst battery there is , but something that is associated with a reasonable probability of occurrence and then basically distill it down to a pack with certain energy content , going into thermal runaway with all those goals . What does that mean at the level of the fire and then potential explosion use ?

Wojciech Węgrzyński 28:09

Can we really afford that ? I'm worried with a scenario where you would have an outlier type of a vehicle or battery that would be associated with a very high hazard . You would have most of the vehicles that say , with the batteries that are not so based on probability , not that worst case scenario , we would be designing for most of them . And then the one horrible battery comes into my car , creates a huge fire and what the media says is not that they're oh , this was an outlier , it's okay . It would say electric batteries are going to kill us . That's what media will catch up and you know that very well . She's challenging .

Ali Ashrafi 28:45

So , vojicid , I want to say two things . One is that first discussion that we had in the beginning that the big picture context is important exactly because of this . Right , it is a naturally human tendency to , when you see something new , to see it more often , right ? So if you see a fire from an electric vehicle , it catches the attention just naturally more , right ? I know , like , when , if I buy a car , I see that car more often in the street . It's just , it's just natural , right .

Ali Ashrafi 29:14

But we are talking in the context where climate change is having real large scale , scale of hundreds and thousands and , you know , as it becomes worse , tens of thousands of lives impacted and billions and billions of dollars of damage , right . So we have to remember that context . So things should be balanced . That's one piece of it . But then back to your , your broad question . I mean , our designs generally do have to be robust , right ? That's why , unless we have specific information , we don't design for one specific type of case , and there are cases where we have that , right . Sometimes we are working with a specific system and manufacturer in a specific area and we know exactly what they're doing , and that's part of the conversation . You can customize the design for that , but in the context of a building that's going to see energy storage in various forms of different technologies , including technology , but the changes in the same technology , we have to be reasonable but also robust in our design so that we can provide a reasonable envelope of what's going to happen .

Wojciech Węgrzyński 30:23

And now let's talk about mitigating consequences . So how can you act on this layer ? Like preparing your building for a battery fire . If you have a battery storage system , you at least know your opponent , because then you have a chance to design and you know what type of cells , what type of system there is , at least until it's replaced by something else . In terms of vehicles , let's say , okay , we have a probability distribution of what type of fires you can find . So how would you prepare your building for consequences , what kind of approach and technical solutions you could apply to prepare for that ?

Ali Ashrafi 31:03

Let me start with an analogy . Let's say a common building and we're designing for standard fires , right ? There are so many different types of things inside the building and they have different types of heat release rate , buildup of the fire , the toxicity , all of that right . But we look at the range of things that could happen and define what is reasonable , and some of that becomes physics-based meaning . If you know the nature of what's burning , you can come up with reasonable bounds , independent of whether it's a sofa or a bed or something else , right ? So there are some similarities between lithium ion batteries right , there are differences , but there are also similarities , and there's a range of specific gases that are released .

Ali Ashrafi 31:44

So , based on the physics of that problem , there is a bound to what's going to happen . We can define what that bound is , and so , within that context , then it becomes a question of quantifying all those various elements and then trying to come up with the right solution in the context of your building . So the explosion risk , the fire risk , the toxicity risk , but all of those things being equal , if you have a building that's much more heavily occupied and people are closer to that risk , versus a building where you have less people in it and maybe you have more distance between them . The solution could look very different , right , but we have physical limits on what could happen and we could use our understanding of the physics to come up with what's reasonable and robust at the same time .

Wojciech Węgrzyński 32:35

So , from this context , what I distil is that there's no single bullet , no single solution that solves the problem . It's all scenario-based . So in the end , actually , the solution is performance-based engineering to some extent , and turning your building into something that responds to the threat that you have now quantified and understood . And when you're going through that performance PPD process , what types of solutions or layers you would play , like detection , suppression , smoke control , all of it , fire resistance of your walls , like where do you guys , engineers , put your eyes on when you approach such a project ?

Paweł Woelke 33:11

I'll just say one thing , something you said , poitak , that I think is worth emphasizing , and it's building on what Alisa said earlier there's no single solution , there's no silver bullet , and it requires layered approach . It requires all of the elements of the typical solution . Not a typical solution nothing about this is typical but strategies that are often used to manage the risk , and the key element of it is that , despite the variability going into what you're dealing with from the point of view of the type of battery that may be initiating you . So , basically , the layered solution is what has to be used for every single person like this , and it is very strongly dependent On variety of other things , like the level of ventilation in the building , for example , the amount of confinement and congestion that you're providing to the gases that are ejected from the battery , what sort of gases are being emitted at their formability limit is . All of those different things are basically a necessary consideration to design a solution .

Wojciech Węgrzyński 34:07

So , again going back to the comparison of the desert power wall and the , let's say , residential battery that's used to power the house , a vehicle that's moving around to set up like what are we , what are goals , what we are protecting for . So If you could go through like what would be your number one objective when you're designing a fire strategy for a large out of the city center , something more like a part of the building and something that Is just a place where accidentally or where , for you , for other other reasons , of a battery may occur , like , appear like it's car park or something yeah , right yeah .

Ali Ashrafi 34:51

So those two are very different context for design , and so the objectives and the solution could look very different . So let's take the easy one first . Yeah , I wonder what's the easy one ? Go on , so you have a large amount of energy storage , but in a place that's remote , in a desert like it's , in a place that's not occupied , right away from other things , it's actually much easier physical problem to manage because you have an outdoor environment . The Gases mostly dissipate and go up , the heat dissipates , the hazardous materials dissipate , you're not worried about impacting someone , and so all it comes down to what can you do to make sure that you could minimize the extent of damage and minimize the consequences so that it's your functionality still there ? So let's say this is energy backup for for something . You could lose a module somewhere and you could contain it and you can continue to have that system operate as a power backup .

Wojciech Węgrzyński 35:53

That's a much easier problem so you design simply for resiliency of the infrastructure like and to not damage it's , it's fundamental girl in being a battery storage for a facility . So just separation distances and stuff like that and you assume a park can just die from the fire and as long as as the majorities on harm , you're good to go right .

Ali Ashrafi 36:15

I would say mostly . So . Now , again , it depends on what the client looks for , right ? So the level of that would be higher or lower . But , yes , you're trying to minimize the actual damage and you're trying to maintain the functionality of that system . So have a more resilient design , cool .

Ali Ashrafi 36:31

When we go to the other end of this , which is now you're in the middle of dense urban area , potentially inside the building , is a totally different problem , right ? So now you have the risk , same hazards , but you have people close to it . You have a lot of assets close to it which create its own problems . A , it changes the nature of the physical risks that we have , right ? So if you have , if you're in a more contained space , the fire impact is different . You have more of an explosion potential . The hazardous material is released inside the building . Your access is more limited , right , so the fire service has more limited access compared to an open area , right ? And then you're looking at okay , this is happening . Where are the people ? How far are they from this ? Can they evacuate in a safe way , given the level of risk ? Is there is the redundancy in that If somehow they need to shelter in place or they take it takes them longer to do that because it's a vulnerable group of people . What can we need to give them that extra level of time to deal with that ? Right ?

Ali Ashrafi 37:39

The fire service task is again , as it's a , much more complicated for the same reasons they're going in . There is that direct , direct risk of the fire , but they have to protect the people . They need to make sure they manage the extent of the risk . If it's a building , you don't want the building to be damaged and affect something that's next to it , and sometimes these things happen . You might . You know there's a large fire , they might evacuate buildings and a block next door . So that's , that's a larger impact , and these fires take long right . So when it comes inside the dense urban area , suddenly the consequences become much more important and the physics of the hazard also becomes trickier . Right so that balance of what's the right solution , and so that's where we need to come up with solutions that are specific to , to the context of a specific location and suppression to what ?

Wojciech Węgrzyński 38:34

and you find suppression is a part of this and a specific approach yet ?

Paweł Woelke 38:39

That's a very good question again . So there's no . If you just look at it from the point of view of the lithium ion battery itself going into thermal runaway and basically being on fire , there's no single fire suppressant . That just addresses the situation , which is one of the key challenges , because you know the typical design , even performance basis , often based on the response time or why , are breaking , basically arriving on the on location and addressing the situation . They arrive right right now . They've got limited means of putting the fire out . Now , that said , water is one of the most effective ways to keep temper . The only problem , or the problem with water based solution as a single . Again , if it were to be treated as a silver bullet , the amount of it required to remove enough heat to stop the cycle from propagating would be would be basically impossible , not effective for a typical building to handle .

Wojciech Węgrzyński 39:33

But . But it's not because of the ineffectiveness of water itself , it's because of the way how you can apply water , like there is no good way to actually apply it effectively into the battery or that's correct .

Paweł Woelke 39:47

Yeah , so you'd have to immerse the battery in water , in the pool of water . Right , and if you think about this , let's just say , hypothetically speaking , of every single spot had a pool , that would allow you to basically immerse the battery that's in the process of thermal right away in that pool , and that pool wouldn't necessarily have to be big enough to merge the entire car . So you're not talking about the potentially impossible amounts of war , but right now , because of the way it's applied , the amount of water you would need in a sprinkler system , for example , it's just not feasible , in part because of what you said .

Wojciech Węgrzyński 40:19

But again , if we're thinking about the whole building safety strategy , we very rarely expect that sprinklers will suppress the fire completely . They are supposed to . At least we're talking yes , if our sprinklers in warehouses , they are supposed to control the consequences and provide a chance for fire brigade to attack the fire . So I don't understand why would we need , in this particular case because it's a battery why now it would be expected to contain it . And I think this also gives us a better chance as engineers to engineer the solution , because we're again back to our usually no bounds of how we design and where we design .

Paweł Woelke 40:59

So the only difference yes , so everything you said makes perfect sense . The difference is that you contain the situation or prevent the fire spread or keep the temperature down with the sprinkler system if it's a solosically even hydrocarbon fire . Four first responders arrived here . The first responders arrive and they don't have any active fire suppressing that would put the battery

Fire Suppression and Explosion Control Challenges

Paweł Woelke 41:23

out .

Wojciech Węgrzyński 41:23

Ali , what's your take on this issue of suppression ? How do you view it ?

Ali Ashrafi 41:28

I mean , I would reiterate what Pavel said we do have a layered approach , right , and so each of these layers , if it doesn't fully contain the risk , but if it mitigates these consequences , it's still part of the solution , right , and so , when you look at that , if you can keep the temperature lower , that could be part of the solution .

Ali Ashrafi 41:49

If you can slow down the propagation of fire from one set of energy storage devices whether it's vehicles or something else to the next , that is part of containing and managing the consequences , right , so it certainly fits that . It's just good to remember that here we are dealing with a context where , once you've released some of those gases , if they haven't burned , those gases are still available and can later potentially be involved in an explosion . Right , you have a mixture of gases that includes , usually a lot of hydrogen , which expands the range of flammability , and so it's not just about putting out the fire . You might still have all these gases that are there , not uncommon in standard fires too right ? Sometimes you have what you call like a back draft , right , but here it's more of a challenge because you have a lot of hydrogen in the mix too , which expands that explosion limit .

Wojciech Węgrzyński 42:42

I'm also thinking , you know , from an engineer's perspective . If I was designing a car park , I had sprinklers in it . My role would be to make sure that the conditions when the firefighters arrive are good enough , because then they can handle , Like , is it feasible to assume they can handle in this scenario ? Like , should our design go beyond the fact that we only need to prepare the battlefields for firefighters , or should we go a bit further than usual ? Because it's not that I don't believe in the abilities of firefighters I mean , these guys are usually heroes and I fully believe they would do everything they can but it's technology and capabilities and other things allowing them to actually successfully intervene in this type of scenario and , just you know , take the responsibility out of the building under actions to provide safety . You know , ongoing safety .

Ali Ashrafi 43:35

Right , it is a much more challenging job for a firefighter right ? I mean New York , so the fire department of New York is probably the leading place in terms of not only figuring out what to do on their own , but trying to educate everyone in this area , absolutely moving as fast as they could . It's just the nature of the beast . That is a very challenging problem and it's different from the type of fires that we have dealt with before from a firefighting perspective , right , and so when you're looking at designs , I think part of design should be there is less of a chance to just put down that fire quickly , and it might be that in many of these scenarios , the best the fire service could do would be to mitigate and control the fire to some larger area Right , and then that fire might burn for until it burns out , right .

Ali Ashrafi 44:28

So it is a different problem . It doesn't mean it doesn't have a solution , but the solution has to be looked at in the context of a specific building , right ? So just to give you an example , the last time I was here the focus was on firefighter safety . So let me look at it from that perspective . If you're going there and there's a fire and you've managed to move all the people out and away from where the risk is . It's much easier to have a much more defensive posture and try to just wait it out . Yeah , wait it out and make sure it doesn't spread to other places .

Wojciech Węgrzyński 45:05

But that's where I struggle . What would the public do to fire service if the message that went into press was ah , the firefighters did nothing but looked at the fire for 10 hours ?

Ali Ashrafi 45:18

You know , I think the public generally understands the heroic job that fire service does and they make those judgments all the time , right ? They go to a place and they need to see what's at risk . We cannot put fireman life at risk unnecessarily . If you can contain something and there's no major risks to life , right .

Wojciech Węgrzyński 45:40

But yeah , I also mean that as a fact that perhaps unnecessary action would be required for firefighters Like is it okay to just take the vehicle outside of the building and controlably watch it used the reminding fuel and get to a safe state ?

Ali Ashrafi 45:59

I'm not talking about one car . Look , we're really not talking about one car , because the scenarios where one car somewhere is burning and you can move it or manage that , that's very manageable .

Ali Ashrafi 46:10

We're really talking about situations where one of these things starts a fire , but you have propagation . That's the challenging problem , right , and part of the goal would be to make sure that we can come up with solutions , working with all the stakeholders , including the fire service , to make sure that , in the context of that building , we have a plan where you can quantify the risk , you can mitigate and manage the risk . You have a plan for what happens to people , because that fire is likely going to go on for some time and you want to move people away from the fire , and you have a plan where the fire service knows if I'm going into this building . This is a plan that gives me the maximum chance of protecting people and the life of fire service at the same time .

Wojciech Węgrzyński 46:56

And in this discussion a few times we've mentioned that the new part of the hazard is an explosion hazard . So how does that affect your fire engineering strategies ? Because now you're also an explosion engineer . I'm not sure how many of fire engineers are routinely trained in dealing with that . So to what extent this is an increased challenge for you , for your office , that suddenly this also isn't , and how big part of your assessment is actually is .

Ali Ashrafi 47:28

It is a big part of it when we go and look at it again inside that dense urban area . I want to highlight it's in terms of the physics of it . It's nothing new , right ? Meaning you have a mixture of gases , usually hydrogen and then some hydrocarbons , and we've dealt with them and explosion potentials with them for a long time , right , so we know how to do that .

Energy Storage Fire and Explosion Risks

Ali Ashrafi 47:50

The challenge is the context here , again right , where you have a potential fire , you have the potential for explosion , and the solutions for those two things are not necessarily identical , meaning you have to quantify both of them and see what's the right solution for you . Part of that is how much of the gases are you trapping in that space ? So Pavel mentioned ventilation . That's a big part of that . Can you move some of the things that are being produced from the space , or are you trapping a lot of those gases there , for example ?

Wojciech Węgrzyński 48:23

Right . So actually the solutions could be almost contradictory , because for explosion you would like to have a relief surfaces , potentially openings to the exterior , and for fire you often would go into confinement . You know fire resistance thick as hell walls , exactly opposite . So that's a challenge for sure .

Ali Ashrafi 48:42

You're absolutely right . That's why it's not a simple problem . Right , you're right . In simple fire cases inside the building , you compartmentalize . Right , you create barriers and slow down the spread and done For explosion . That's the worst thing you could do . Now you've created a confinement that makes the effect much larger . You want to allow the things to spread In the context of the building , where you have both of those risks present at the same time . Now you have to see what is the right solution that balances all the risks . There are elements of modeling both of those things . What does the fire look like ? What does an explosion look like ? It ties into how much room you have for gases to spread into . It ties into the function of your ventilation system . There are many things that go in there . We understand all the pieces . We can combine them and look at them together , but that's exactly why this is a unique kind of problem where we need to look at the right solution in the right context .

Wojciech Węgrzyński 49:49

I'm thinking . Is there an example of existing technology which we would approach in a similar manner ? I think transformers to some extent . If you have high to medium or medium to low voltage transformers in your building large devices I guess it would be in many cases very similar approach , especially that it's also electricity arcing hazards . Is arcing a hazard that you consider in these cases ?

Ali Ashrafi 50:15

I think it goes back to you have something that's going to cause the problem to start , but we're taking for granted that something goes wrong , that something goes wrong at a large enough scale where you have to deal with it , so the source of it could be anything . But back to your question . We've dealt with hydrogen safety for a long time in the context of energy . Usually it's just usually you're not doing it as close to a population center . So a lot of the physics of the problem are known and we've dealt with them . We have all the framework . It's just a question of you're applying the same tools of engineering and science , but you're designing safety in a different context .

Wojciech Węgrzyński 51:00

I also think , a lot of auxiliary things around we can learn from , let's say , power plant industry . They've dealt with massive cables , transformers , fires of high consequences for years . So we , as a fire engineers , we need to understand that we're not dealing with simple residential fires anymore . It's industrial . Fires have entered the space and perhaps we should consider them like that , and what you and Paweł said in this interview are very close to what process industry would do protecting a chemical plant or power plant . This is the mindset that is used for ages . It's just not in our part of engineering buildings for residential use or car parks . Okay , paweł , and what's your take to summarize the talk so far ?

Paweł Woelke 51:48

So , just to sort of close the loop on this . I think that , despite the severity of the situation , or the severity of the scenario that we're talking about , we believe , based on everything that we've done , that the situation , the risk , is manageable . There are solutions out there , and they require a pretty deep level of understanding of what you're dealing with . So you have to start with characterization of the fire and potentially explosive event , as well as the toxicity , and then you have to implement the layered solution that addresses as many of the factors that potentially can be effective at stopping the chain of events or reducing its consequences , and then you can develop effective solutions to the problem .

Wojciech Węgrzyński 52:27

Ali Paweł gave his final words . This is time for you . So your final consideration for engineers who will be dealing with these new energy storage solutions in their projects .

Ali Ashrafi 52:42

I just want to add , putting this again in the context of we are trying to deal with climate change , which is a large-scale , major risk to life in many aspects and also to the way we live as a society , and so any risks that we're dealing with here are balanced in that context . We don't want to overstate the risks . We don't want to understate the risks . Energy storage is a critical component of the fight against climate change , and lithium-ion batteries are the dominant technology in that space , at least at this point , and so we do have the tools of engineering and science to make sure that that technology is incorporated safely . We just need to make sure that those tools are used consistently so that , as we are expanding energy storage , it's done safely , and sustainably .

Wojciech Węgrzyński 53:36

Okay , guys , I was a huge pleasure . Thank you so much for sharing your insights and how to approach this problem . Especially thanks for setting the context why are we doing this ? And the considerations that go through engineering . So yeah , thank you so much and see you again in Far Science Show .

Ali Ashrafi 53:56

Yeah , thank you for having us and congratulations on passing the 100th episode . I think you're doing tremendous service today in the industry Cheers .

Wojciech Węgrzyński 54:04

Zala Well done .

Ali Ashrafi 54:05

Thanks .

Wojciech Węgrzyński 54:06

Thank you , cheers , bye . And that's it . A lot of interesting thoughts and solid fire safety engineering with a strong emphasis on performance-based engineering , something I like and appreciate a lot . In this episode , I was kind of surprised at the take of the guys on how important the new fuel carriers are for the whole context of global warming and bigger goals that we have behind . I always say as fire engineers , we need to appreciate more why people are doing things that they're doing , and once you start to place our solutions within the broader context , suddenly our solutions become better and more responsive to the needs of the other side . So I certainly must appreciate this way of thinking that only in Paweł have presented in the podcast .

Wojciech Węgrzyński 54:57

I hope you've learned something new in this episode

Inspiring Fire Safety Approaches and Engineering

Wojciech Węgrzyński 55:01

. I hope the approach to the engineering , the fire safety challenges of new energy carriers that guys presented was something that inspires you and perhaps you will find useful in your engineering . I certainly will in mine . So , yeah , thank you . Thank you , paweł , thank you Ali , for this interesting discussion and looking forward to learn more from you . And this is it for today's episode . I really hope to meet you here again next Wednesday for the next episode of the Fire Science Show . Thank you bye . This was the Fire Science Show . Thank you for listening and see you soon .