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Why Has No Production Car Hit 300 MPH? Electric Cars

Why Has No Production Car Hit 300 MPH? Electric Cars


Hello everyone and welcome! This is the fourth of a Five-Part Series where I have partnered with Formula E to talk about electric car technology and in this video we’re answering the question could an electric production car be the first to hit 300 mph. Now the premise for this video stems originally from an older video I did asking the question “Why has no production car ever hit 300 miles per hour?” And in this video we learned a big part of why cars haven’t hit this 300 mph mark is because of the drag, the aerodynamic drag placed on the vehicle. And with internal combustion engines you need a lot of cooling, and that cooling means you need additional drag because you have to pass air through the vehicle. And so a lot of people in the comments asked you know “Would It be easier to achieve this 300 mph goal using an electric car?” Because they’re far more efficient and then perhaps they wouldn’t have that aerodynamic drag because they wouldn’t need as much cooling. So that’s what we’re going to discuss in this video. Now as was discussed in the previous video this is our equation for power, how much power we will need to reach a certain speed. That’s being V for velocity here in this case 300 mph. Now you have to break this down into three different sections. Here we’ve got drag, rolling resistance, and your drivetrain efficiency. But The biggest part of what’s going to cause you to need a lot of power to reach a high speed is aerodynamic drag. And so If you look at this equation right here the most critical component is this coefficient of drag multiplied by the front surface area of your vehicle. Because as you can see it’s multiplied by V squared and V. So you have to multiply the coefficient of drag by the frontal area of the car by velocity cubed. So as speed gets higher the amount of energy you need to overcome that aerodynamic drag goes up by velocity cubed, so obviously it’s extremely important to minimize the coefficient of drag in the frontal surface area to keep this number right here low so you don’t need all that much power. Now with internal combustion engines, this coefficient of drag is heavily influenced by the cooling system because you need all of that extra air to cool down you know the engine, the transmission, things like that, and so could you know an electric vehicle have an advantage in this scenario?
And one of the interesting things to think about and something that’s not often thought about when comparing these two systems is the fact that internal combustion engines operate at a pretty high temperature. So about 200° Fahrenheit or about 95°C Versus electric vehicles, i’ve actually worked on a cooling system for an electric vehicle and for some of the components they were allowed to get up to 60°C, for some of the other components they were allowed to get up to 65°C in Formula E you really don’t want your battery temperatures exceeding 62°C. So we’re just going to say that our maximum coolant temperature here is about 60°C. Now if we have the same exact size radiator and we have ambient air at 20°C, passing through that radiator you can tell that you’re going to reject a lot more heat with this radiator than with this one even though they are exactly the same, and the reason being is because your temperature differential between Your inlet coolant which is 95 versus your ambient air Which is 20 so about 75°C here, Versus 60 going in the inlet for your electric vehicle 20°C ambient air means you only have a temperature delta of 40°C so this is going to reject a lot more heat, this isn’t going to reject as much heat, and these kind of play you know to balance out because the internal combustion engine needs to reject more heat it’s far more inefficient so it has a lot more heat to reject but it’s better at rejecting that heat because it operates at a higher temperature. On the flip side the electric vehicle has less energy to reject because it’s far more efficient but it’s more difficult to reject that heat, because the temperature delta between ambient air and the coolant going Into your radiator is going to be lower. And when I was developing a cooling system for an electric vehicle what I noticed is that I was using basically the same sized radiators as our internal combustion equivalent vehicles were using, even though we were using an electric vehicle that was far more efficient. Now let’s dive a little more into the cooling systems on Formula E cars and these have two separate cooling circuits. The radiators will be housed in the side pods of the vehicle and you’ll have one cooling circuit for the battery, one for the motor and the inverter. And actually because you know Formula E races are relatively short and they switch cars halfway through so you know we’re thinking about 45 minutes to an hour somewhere in that range of time that these races last and only that in one car they actually don’t cool their transmissions because they can get away with it you know it’s only running out there maybe 25 or so minutes, and as a result it’s not going to get hot enough in that duration. It’s efficient enough that they don’t have to worry about It and they can run out there. Of course some teams are only using one gear so it’s even less of A concern you know not as much moving components in there, but regardless they don’t actually have to cool their transmissions since the duration of that run is relatively short. They do of course have to cool the battery and the motor and inverter and one of the challenges they run into is that this battery cannot exceed 62°C or they start to get reduced performance of their vehicle and so there are races in which Formula E goes of course all around the world where their air temperatures are as high as 32°C so remember this temperature differential is getting smaller and smaller and so what that means is this cooling circuit is less and less effective at rejecting that heat and so when they do run in scenarios where ambient temperatures are so high you know some of the strategy changes they have to make they have to reduce the amount of regen that they use, because that regen is putting heat back into the battery pack and ultimately if you know reducing regen isn’t enough they will have to limit throttle if the cooling system isn’t capable of rejecting all that heat the first thing of course you want to do is reduce regen but if that’s not quite enough then you would go into you know scenarios where you want to lift and coast and maintain energy in that battery and not get it too hot. So going back to our original question, ‘Will an electric production car be the first to hit 300 mph?’ It’s really not any less of a challenge than it is for internal combustion engines and reason being is because you’re still going to need significant cooling as a result of those lower coolant temperatures which will influence your coefficient of drag and that means you know ultimately you’re going to need similar power levels as an internal combustion engine to reach those high speeds that said it does have an advantage from an energy standpoint internal combustion engines throw about a third of their energy out the exhaust another third of that energy just into heating the coolant surrounding the engine block wasted as heat and then a third of that you know turning eventually into useful work of course you have those drivetrain losses, but much less efficient than using an electric car. So the electric car will need less energy but It will still need very close to the same amount of power if not the exact same amount of power in order to achieve something like this. So thank you all for watching if you have any questions or comments deel free to leave them below. be sure to check out Formula E’s channel, they’ve got all kinds of neat information about how these electric cars work that kind of thing and i’ll also include links to the previous videos of this series which I made, hope you enjoy them thanks for watching!

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100 thoughts on “Why Has No Production Car Hit 300 MPH? Electric Cars

  1. Why don't they use a heat pump/inverter to increase the temperature differential and therefore decrease the radiator cross section?

  2. How do you see the possibilities of an electric plane? Would it be feasible? Excellent videos Thank you very much. Best regards.

  3. The two way land speed record for a piston engined wheel driven vehicle exceeds 400mph and was done with about 2200hp.

    My guess is the next Bugatti will have 2000hp and be able to exceed 300mph, even with all that weight. Tires and reliability are the biggest issues.

  4. What would be the requirements for an engine to run on “water” or run an engine off the two elements that make up water?

  5. Hey I'm currently a sophomore in high school and I'm interested in being a mechanical engineer I have seen your website but can you make a video to clarify please? Thank you

  6. So the motor in these cars is about the size of a washing machine motor but maybe longer: so 6"X12"? Thats way smaller then an engine if that diagram is accurate.

  7. I gave you a thumbs down because I don't like metric temperature without a U.S. equivalent. This old dog isn't going to learn any new tricks.

  8. What about using a liquid gas cooling system. It can also be vented out the back and reduce the low pressure behind the vehicle

  9. This comment is irrelevant to the video but I wanted to take the time to say thank you so much for uploading these videos that have tought me so much about cars … I now know exactly how my 2015 sti works and your explanations or always great! I owe my engineering knowledge to you thanks!

  10. Can you make a video about the "Aspark Owl" that was shown in Frankfurt this year?
    Is the acceleration of 0-62mph in under 2.0 seconds really possible?
    Thanks in advance.

  11. Quick question; What is the observed energy density of the best production battery on the market vs. 95 octane gasoline? Wouldn't the energy density of the fuel source and the mass of it's container and delivery system play a role in vehicle top speed due to the engineering constraints surrounding the problem of significant increases in mass of the vehicle? Im referring not only to straight line performance on a specially built track, but the reality of making a heavier vehicle handle real roads at speed.

  12. I wonder if it would be possible to use a technique that is used in freezers/refrigerators to raise the temperature in the radiators drastically so smaller radiators could be used.

  13. Answer is no. Electric Cars are slower than ICE powered cars, and also are a lot slower on the 60-120, and suck in corners. Not to mention what everyone else in the comments are saying about the fact that the current tire technology is unable to cope yet.

    Short answer, neither electric nor ICE is 300 capable until tire tech advances.

  14. For a short duration of operation, would a cooling system that kept the liquid nitrogen work? It would lower the drag while keeping the ambient temp of the cooling system much lower, allowing the cooling system to take more heat from the batteries and motor.

  15. The P-51 mustang created a net thrust from it's cooling system. So at speeds of 300mph you could use the cooling system to create thrust to negate the increase in drag.

  16. Bugatti lists current top speed record at 261 mph but they hint at 28? mph in a video
    they are confident that they can achieve that other wise they would not list it.

  17. You can redirect regen to useful work to an air compressor and carbon fibre air tank then that can drive an air motor connected to an air conditioning compressor to send it to a heat exchanger creating a peltier effect. You can amplify the heat delta by using actual peltiers on the parts needing cooling. The system would create higher radiator temperatures and therefore the size of the radiators could be reduced.

  18. what about using heat pump in electric cars to increase the temp of coolant in radiator thus decreasing its size?

  19. One thing that is not mentioned is that electric vehicles still have potential for increases in efficiency.
    Better batteries will need less and less cooling as their internal resistance goes down. Eventually you will not have to cool the battery at all.

    1% better efficiency in the motor at 300mph ( totally possible ) will make for 10,000's of watts of heat not being produced.

    The ICE on the other hand, is really tapped out for efficiency increases these days.

  20. I guess theoretically the waste heat couldn't be used to create thrust using the Meredith effect like the P51 mustang. The electric motor would still have an advantage because it could produce the same power in a smaller and lighter motor. It would also be possible to use a compressor to reject more heat, like an air conditioner, but this would consume a lot of energy.

  21. Could you convert body panels into radiators? I'm thinking, an aluminium spoiler with water pumped through it. Also, why not use peltiers or another mechanism to increase the temperature differential?

  22. Awesome channel, so informative and educational. Can't believe I wasn't subscribed. Until now, of course 🙂

    This may be too simple of a solution, but what if some sort of refrigerant was implemented in the cooling design of an electric vehicle? Similar to how the Dodge Demon cools it's IAT's by using the A/C system. This should increase the temp delta between the max desired temp (60 degrees C) and the temp that is cooling the cars components down. I know there would be some parasitic loss by using something like this, but would the benefits of such a set up outweigh the drawbacks?

  23. Engineering Explained, do you think Hennessey will actually be able to pull this off with the venom F5 and if so how would they if they have to counteract so many different variables which you explain here and in the other video?

  24. Hey, I know its really impratical, but then again so are these cars…. But thinking of what you said about the delta T being the limitting factor, if you were to use 2 coolants, the first being water/ antifreeze based and the second being a compressible gas refrigerant, could you use this to make a 'mini radiator' where the heat is concentrated more resulting in a bigger delta t? My thinking is that at high speeds this smaller radiator would allow a lower cd, and this would more than make up for the inefficiencies of running another compressor. I think it would be ineffecient at low speeds, but it could have some kind of retractable shrouding to lower the cd so only the miniradiator is exposed when the car is attempting top speed.

  25. No numbers = no point. One thing is more and another is less. What does that say? NOTHING. Unless you put up the actual numbers and calculate ratios this says absolutely nothing about the electric cars. Your Bugatti video quoted it needing to reject 3000 HP worth of heat at full power. Would a 2000 HP electric car running at ~95% efficiency need to work just as much to reject its 100 HP worth of heat due to lower thermal difference? Hell no, that is just absurd. And even if that was so – then it would make sense to use a heat pump to concentrate the heat and bring the temperature differential up. It is really cheap at those levels and we are talking about reaching top speed, it does not matter that this would empty a 100kW battery in 10 minutes. And then you can actually take lower Cd values from actual electric cars and see how much power would be needed to reach 300mph with those cars. There are plenty 1MW electric cars out there already, it is close.

  26. Would it make sense to use some kind of heat pump to increase the temperature the radiator is seeing? Of course, one would need pretty high performance heat pump to not be limited by it.

  27. What about using a heat pump, so the radiator is hotter? And therefore could be smaller. Would the mass saving be worth it compared to the inefficiency of adding it?

  28. Why not cool with liquid nitrogen? Some production cars cost over $2 Mil and have maintenance needs more expensive than mortgages. Is there any reason liquid coolant can't be used for top-speed mode?

  29. IMHO, this video is a bit disappointing. The title refers to "production cars", but the content is about the Formula E more or less. In the end, for customers of a production car, it will be difficult to actually experience the 300 MPH – neither usual race tracks nor public roads will be allow to reach this speed. Only a few high speed trial circuits and the like allow for these high speeds. So for the buyers of a potential 300 MPH car it will be unlikely to ever reach it. And this means it is not so attractive for the manufacturers to overcome all the physical challenges you have mentioned in this and other videos related to the topic (aero, cooling, tyres, …).

  30. electric cars maybe gunna reach 300+mph at maybe 2020 but u know gas cars are gonna reach 300+ at 2019 and i sayin the truth at 2019 henessey is going to attempt a 301 mph record with the henessey venom f5 😀

  31. 1) if tires are not capable of handling high wheel revolutions then it is needed to make wheels bigger ….and about 20% bigger than they actually are on a veyron. That will reduce rotation speed of a wheel travelling distance. So this one is actually not that hard to comprehend.
    2) Electric batteries are heavy and that is actually a big + to top speed, because the car will be more stable at high speeds if the power is enough.
    3) If you designing a car to be able to race or cruise at high speed you DO need alot of cooling but if you want to make a kinda mid speed GT cruiser that IS capable of acheving high top speed for a short amount of time, you won't be needing that much of flow cooling just some internal ratiator that will suck the heat while the car is getting to it's top speed.

  32. Make it yourself thanks to Avasva solutions. I think it's the best way to learn how to build it in the cheapest way.

  33. Hennessy Venom F5 Has (not in production / not complete) 1,600hp And according to Hennessy will hit 300mph

  34. Can they use a tank of some type of highly compressed (liquified) gas and use that instead to cool components? That way the car can be made to slip thru the wind even better. They could even freeze it before a race to get extra cooling.

  35. use dry ice on the battery to cool it or use refrigerant coolant lines just like a freezer on the old-school freezers has in it that solves your overheating battery issue simple

  36. Could they use Peltier strips to cool the components inside an electric car? If they are adjusted to keep to cold side of the Peltier at 60ºC, the hot side would be much hotter than that, so the ΔT would be larger.

  37. Anyway, if you had a car that can make 301 mph, where could you drive it at that speed? The famous German Autobahns are pretty frightening at speeds 250+ kph. But at 480 kph? Really?

  38. meh. there are plenty of 300 mph cars…just not production. plenty of available talking points. you totally skirted the question.

  39. Or use HVAC to cool those parts below ambient. Then you have more efficient cooling for same drag due to concentrated heat that is output at a much higher temperature as well. But that's nickles on the dollar for the drag vs power issue of 300 mph

  40. If normal cooling systems are so inefficient in electric cars due to the low operating temperatures, why not search for other solutions? Has anyone ever tried hooking up an air conditioning unit to an electric motor. They can reach far lower temperatures than ambient air so that could solve the cooling problem. Of course you still have power loss from operating the compressor and drag from the heat exchanger.

  41. Once you get into the 300 mph variety, aerodynamic forces apply.
    Wave drag, this affects airplanes but they have the luxury of being at 60,000 feet where the air drag is thinner

  42. i just solved that problem with my imaginary Car which has a frontal surface area of 0 m² and a Cd Value you cannot imagine 😀

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