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we have 17 000 trucks what do you think it would take to take a quarter of those offline and charge them overnight what would the utility requirements be like we are talking about batteries versus hydrogen cars hey i'm diana you're watching physics girl we are back with our renewable energy series my production team and i went on a road trip around california surviving just on hydrogen by the way thank you to toyota for sponsoring this entire series and for giving us the keys to the car this one is about hydrogen in transportation and specifically we're going to compare battery electric vehicles to hydrogen i mean okay hold on step back why are we doing this video i care about the
environment but the way that you show you care is you learn and so i went and did that there's battery powered electric vehicles and then there's these fuel cell electric vehicles they're both electric vehicles so if you say an ev you're talking about both technically and we learned that people love to compare even the hydrogen people love talking about how people love comparing them battery electric vehicles are here right they have caught on so my first question when we got into the hydrogen fuel cell car was okay why do we need hydrogen i didn't even know that hydrogen fuel cell cars were on the road which they are in california and in a number of other countries i'm focusing a
lot of this discussion on california so let's start the competition between battery electric vehicles and fuel cell i'm going to start with driving range how far can you go in these cars most electric vehicles battery electric see i did it so most battery electric cars can go between about 100 and 200 miles one of the higher end battery electric cars can go about 387 miles hydrogen cars are averaging about a 300 mile range so they're already getting up toward the best battery cars and the 2021 mirai xle which is another version of the car that we were driving has an epa estimated range of 402 miles so they're pretty close in driving range but let's move on to refueling and it's gonna get a lot
more complicated refueling time let's talk about the time to refuel a battery electric vehicle it's on the order of hours if you're using the super fast chargers it could be as little as a half an hour when you're refueling with hydrogen it takes about five minutes but one thing that we talked about in the last video is that the experience driving a hydrogen car had so much to do with thinking about where the stations are we actually visited the very first hydrogen station in california in order to meet up with the director of the advanced power and energy program at uc irvine the first station here and the first one in the united states was in january of 2003. so now it is may 2021
there are 45 hydrogen stations in california so for comparison on the numbers 5 000 supercharging stations and there are about 45 hydrogen stations in california so the one thing i will say is like if a hydrogen station is down that adds a lot of time to your refueling time battery electric vehicles went through that phase as well they're a lot further along in their ascent to the mainstream so there's about 15 million cars and 250 000 of them are battery electric then there's 8 000 fuel cell cars that's how new the hydrogen technology is we have now almost 8 000 cars on the road in california so we started with hybrid electric vehicles in kind of like the 90s or so those took off like a hockey stick where you're coming up and not quite going
up this way in the market in energy we talked about that as being a kernel development time and then you get to a point we call the activation energy when the market self propagates it just grows that's what we're seeing now with these fuel cell and battery electric vehicles you sort of saw this with electric cars actually but the crook of the stick was in about 2012. hydrogen is obviously a lot further behind there's i think about 8 000 gasoline stations for cars in california so by doing some work and actually figuring out how many you would need to cover that same amount it's maybe about a thousand stations and it can be co-located at gasoline station the other thing to consider is where you
can refuel 50 of people here live in multi-family housing we don't all have garages we don't all have parking spots we don't all work at forward leaning technology company that lets us charge for free when we drive our electric vehicles to work right i live with roommates and i cannot put a charger into the house that i rent but i could do hydrogen if there were a station close enough to where i live so what have we got we've got the stations are very few and far between it can be much more convenient to charge at home but not everyone lives in a home that they own where they can put a charging station everybody loves the competition so let's move on to efficiency so if we
first look at the specific energy of hydrogen versus batteries and that is a measure of the amount of energy you get per weight with hydrogen it's 35 000 watts per kilogram with batteries i'm talking about lithium ion batteries it's 200 best case kind of close to 300 but the overall efficiency of hydrogen is 25 to 35 whereas battery electric vehicles is 70 to 90. 25 to 35 versus 70 to 90. so let's look now at the losses that happen so in order to get energy to charge your batteries you have to produce the electricity somewhere at a power plant then it sent down the transmission lines and there's some loss of energy in that process and then a small amount is lost to charging the battery and then somewhere in there
there's ac to dc conversion loss and then the loss getting the electricity from the battery to the wheels you're looking at a total loss or a total efficiency of 70 to 90 for batteries so for hydrogen if you do electrolysis which is the cleanest way of getting the hydrogen you lose 30 of your energy if you used a proton exchange membrane it'd be a bit more efficient but those are again still more in the development stage and then you lose energy compressing the hydrogen or cooling it and then transporting it and then there's a significant loss going from the fuel cell to the wheel add all of that up and you're looking at a 25 to 35 efficiency for fuel cells and it's
mostly things that you can't get around which means you have to use about twice as much energy to produce hydrogen and then to use hydrogen for your cars as you do to produce electricity for your battery cars the other thing to consider with efficiency is that batteries lose capacity over time that doesn't happen nearly as much with fuel cell electric vehicles let's look at other uses within transportation for batteries and hydrogen besides just passenger cars the beauty of a fuel cell is it's so modular and scalable so you can go down to there's literally products that charge your phone like a little tiny little fuel cell that charges your phone all the way up to something like a plane
batteries are scalable too you can put them in your phones your computers your truckloads so the general consensus is that both batteries and fuel cells are great for uses in transportation even beyond passenger cars but when it comes to carrying more weight going farther going faster fuel cells have the advantage and the reason why is because of one graph and i'm going to show it to you guys right now what you're seeing here is on this axis you're seeing the vehicle test weight so that's how heavy the vehicle is and then over here you're seeing the range so fuel cell and battery electric vehicles start out about the same it's worse than a linear scale upward as you increase the range of lithium ion
battery vehicles when you get up to 400 miles you're looking at a difference of about 1 500 kilograms one of the people that we talked to was from a nonprofit called energy independence now that is aiming to move away from petroleum independence and we talked about the type of cars that people use where i lived in colorado people really used these vehicles to their full capacity four-wheel drive every weekend for people dogs skis snowboards on top of the cars really have to give consumers what they want if we expect to be successful the hydrogen has a very high gravimetric energy storage density so as you add more range to the vehicle you're not also adding more weight whereas with battery electrics there is kind of a
tipping point where you're just adding more weight and therefore you can't get more range and that's just in the 400 mile range and that's the range we're looking at for passenger vehicles i feel excited about it the fact that it allows people to have choice it's so flexible some of my research has been looking at other sectors other than on-road so looking at ships and looking at rail and toyota among other auto manufacturers are already testing big rig fuel cell trucks we actually got to see one we went to visit one in the port of long beach you know some of the differences that i see as a driver one would be the quietness of the fuel cell itself if you have a passenger you literally can
converse with them actually just about every major truck automaker is developing fuel cells right now so between the likes of daimler volvo freightliner mac all of them kind of funneling and getting on to the development of fuel cells even startup companies haison nikolas is anyone working on battery electric trucks yes tesla's working on them both can be promising though there are added bonuses to going electric for all of these uses pretty amazing that this is zero emissions what we're trying to do for the environment with these trucks and to take the smoke out of the air i got to see a hydrogen-powered boat i got to drive this boat today i thought it was cool and i was really excited
about it and i realized this boat is completely silent seems like from what most people we talked to said there are more promising uses for fuel cells in other areas of transportation especially when it comes to higher weight higher range higher speed the infrastructure for the charging network and the refueling network is not there and it's much less there for hydrogen than it is for batteries there are just not enough hydrogen stations yet there's still some kinks to be worked out we were having issues with the nozzles freezing up so we went from these like very isolated applications for these nozzles where they were used you know by professionals every day consumers were trying to use it while they were talking
on their phone and bouncing a baby or you know we were experiencing these issues and people for some reason decided that pouring water on a frozen nozzle would thaw it out when in fact it was just getting more moisture inside the nozzle and was causing it to freeze more where we need work is on the equipment to have it be more reliable so the new stations will have more than one dispenser if we replaced all 15 million cars in california right now with electric vehicles and plug them all in at the same time at night the grid would fail well hey we have 17 000 trucks at the twin ports here what do you think it would take to take a quarter of those four you know 4 000 trucks offline and
charge them overnight what are the economic impacts of taking 4 000 trucks off duty to charge for whatever four hours 12 hours however long it takes you know when you look at scale that large but if instead you had some of those people charging and plugging in and then some people could go to a nearby hydrogen station in some places it's going to make more sense to upgrade your electrical grid in other places it's going to make a lot more sense to install a hydrogen station my aha moment when i was working in japan i was commissioning a station and you would have a mirai customer come up and then a clarity customer come up and just fill one after another five minutes five minutes and there goes
another zero emission vehicle it made so much sense there are really interesting considerations from an infrastructure perspective how many people can charge where they can charge or how many people can refuel where they can refuel so we take a look at kind of user behavior from proxy vehicles like battery electric and hybrid electric because we think those are the type of drivers who might also be willing to adopt and drive a fuel cell vehicle energy diversification is so important the more diversification you have the more security you have if there's a hydrogen shortage you can charge an electric car or for whatever reason the electrical grid is down if you have a hydrogen cars available you
can go refuel with hydrogen during the middle of day with more renewables like solar and wind we can absorb those renewables and absorb those electricity store and the batteries and then during the night when the sun is not shining and when it's not blowing we can then reuse that electricity and then discharge that back to buildings or homes or the electric grid i think it was echoed by most people we talked to there are no winners and losers the majority of questions that we are asked is what about the battery electric vehicle the bev is that going to win or is this fuel cell electric vehicle going to win yeah but it turns out they're both going to be winners because they're both going to be needed so i grew up in china and smog was like
a really big thing in china and that's what made my mind into like okay we got to find a way to like reduce the air pollutants this like competitive nature that we all have as americans of like wanting to pick this winner and i just want to like scream from the hilltops like hey we need both of these we're not only addressing the climate but we're also addressing that core air quality we're providing a lot of health benefits seeing the change has been really great thank you so much for watching stay tuned for the next video in the series which is going to be about energy storage thank you to toyota for sponsoring this series and happy physicsing
