No worries, I probably should have picked up on it.
I agree flexibility in battery placement can be an advantage. In both handling and interior/exterior design.
I have jumped on the EV bandwagon because it seems the technology is here or very near to make a normal car at a normal price. I am sure some folks want a Zebra, personally when you can get an Aveo for a close price point, I can't find much reason for the zebra...unless I lived in some sort of closed community or a farm or such.
I would buy a Xebra for the previous stated reasons. I would never even consider owning or renting an Aveo sized car. They are of no more value for running errands and they cost 10 times as much to operate. I believe they should be restricted to surface streets as the Xebra will be. Higher cost to own the Aveo, Yaris & Fit. Besides they are also ugly with no socially redeeming values.
I cannot say for certain that the Xebra will be practical for the long haul. They use relatively cheap lead acid gel cells. What else is there to replace? Plus I never have to wait in line for gas or oil change.
personally when you can get an Aveo for a close price point, I can't find much reason for the zebra.
That seems to be a popular criticism of EVs, that they don't make sense from a purely cost perspective. I'm not sure if that is always true. Even if it is true that doesn't mean that they couldn't be marketable. Does a BMW make sense from a cost perspective? Probably not but people assign intangible value to things like style and status. The same would be true for EVs. Driving an EV will be a chance to make a personal statement regarding the oil industy, energy independence, OPEC, pollution, etc.. This holds a lot of value for some people.
The Prius is a hybrid , wow I didn't realize it was. It is true it is the slowest vehicle Toyota makes including wagons and SUVs. I thought it was an electric novelty!
Thanks for the update, WOW prius is a hybrid that runs off both gasoline and batteries. Does that man the golf courses can no longer use them???
No the principles of physics and inertia. Larger smashes smaller. If a fly runs into your windshield does your windshield break and is your car wrecked?
But we are not talking about flys vs cars or pounding in nails. We are talking about cars that can, and are, designed to safely protect its occupants. Drive a 1955 Buick into any small 2005 car in a high speed head on crash and I guarantee you those in the 2005 small car have a much better chance of survival.
If you want to talk physics please put in those safety features such as airbags and crumple zones.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
...That seems to be a popular criticism of EVs, that they don't make sense from a purely cost perspective.
Saving money is the principal reason I drive an EV. EVs are considerably cheaper from an operating cost standpoint, both for fuel and maintenance. This is a major plus for EVs, and this story needs to be told.
Principal costs to worry about are initial purchase price and battery replacements. Driving an EV conversion solves both these problems. These cars, for instance:
Are reasonable to purhase, and old lead-acid battery tech is not expensive. Less than $1000 every 20,000 to 30,000 miles, or about 4 cents per mile. Electricity for driving is only about 1 cent per mile, so total operating cost is very close to 5 cents/mile. (Almost no additional maintenance is needed.)
Li-Ion batteries can meet similar cost targets as lead-acid. Example: look at the price/watt of these Chinese EV batteries (these are available in the USA):
As for production models, EVs do not need to sport high purchase prices. But if we must accept that they will for the time being (because of low manufacturing volume), consider that a fairly typical driver could save close to $200/month in gasoline costs. Subtract the fuel savings from your EV's monthly loan payment, and this makes the EV just as affordable as a car with a $10,000 lower price tag.
Don't get me wrong, I am comparing a the least amount of car I would accept under any circumstances with a car that is less than I would accept. If I were given the choice between a $13k yaris and a $20k ev yaris with a range of 100 miles I would seriously consider the EV model. At 200 mile range it would be no brainer to the electric for me. I just think that with recent advances we don't need to limit our thinking to a car of inferior utility. If Tesla fails and Zebra is the best we can do, then it is time to look to fuel cells. JMO as they say.
"If I were given the choice between a $13k yaris and a $20k ev yaris with a range of 100 miles ......."
But there is no $20K EV Yaris with a 100mi range, nor will there be with the technologies currently known!
More than a decade ago, my employer (an electric utility) was promoting Geo Metro EV conversions selling for $25k+ when a standard Metro could be had for <$10k. Needless to say, they were unsuccessful. As compared to the standard Metro, the EV had space for but 2 people, was underpowered, grossly overweight and had much less than 100mi range (~70 IIRC). The EV was comparable to the standard metro in outward appearance only! Improvements to batteries since then might improve performance and utility slightly while raising price dramatically. Dreaming won't make it so.
Improvements to batteries since then might improve performance and utility slightly while raising price dramatically
Interesting choice of words. Li-ion batteries store 4x the energy per kg as the lead acid batteries in that Metro EV. So in your mind this "might" provide a "slight" improvement in performance and utility. I'd say that is a pretty good bet.
Do you know anyone who has purchased and used these Everspring batteries?
A company called Miles Motors will be importing a Chinese EV next year called the xs200. Top speed of 80 mph and a range of 200 miles. Costs $28,500. That's a pretty good price when you consider that to achieve this range it must have around a 50 kWh battery pack. The 27 kWh battery pack on the Rav4 EV cost $27k to replace.
snakeweasel said : "Well he is suffering from the fallacy that larger is safer. It is possible to make that 2000 lb EV as safe as that 3500 lb sedan. "
Just isn't possible to defeat the laws of physics. Newton stated this relationship in his second law, the force of an object is equal to its mass times its acceleration. You can attempt to lessen it with automatic locking seatbelts, dual level airbags, impact absorbing interiors, electronic stability control, ABS, vehicle skid control, crash resistant door pillars, crumple zones, break away components, SRS, side curtains , etc. But the bottom line is you can't defeat Newton's second law.
Don't over simplify things here. There are many things at play that makes one car safer than the other.
We are not trying to defeat any laws of physics but understand them in order to work them to the best interest of those riding in the car.
Again you can make a lighter car safer than a heavier car by making certain adjustments to it. To say otherwise means that all the safety advances in the last 120 years are for naught.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
you still ignove the laws of Physics. Typical 1955 Buicks were around 3,700 -3,900 pounds and only had lap belts. Yes they did not have crumple zones or air bags. And those features would mitigate some of the impact of a larger car. You say you can "guarantee those in a smaller 2005 car would have am uch better chance of survival". I say it is unknown!. Yes newer cars have more and more safety features, but even the best safety features cannot overcome a substantial weight difference. Why is that so hard to understand.
Here are two good 1955 Buick web sties. They are nostalgic, that is if you are old enough to remember :
P.S. - the last 120 years of safety; now you are talking aboutcars in 1886. Now all credibility is lost . What safety features did Fulton's steam engine have ?
contributes NOTHING to the structural integrity of the vehicle. To the contrary, the batteries are parasitic mass that requires a strong structure to fix in place.
Eventually, it will sink in why battery energy/power density is the EV achilles heel.
I will question your UM study. They make some statements that are misleading. They say that PU Trucks are more unsafe than any other vehicle. If you read their double talk you will see they are saying to the smaller cars that may be involved in an accident with the PU truck. The Insurance Institute always rates full size PU trucks very safe. And insurance rates are in line with those findings. You are at big risk in most compact cars. Civic and Corolla are very high risk cars according to the Insurance companies. They should know they pay for the carnage. If you want a very safe midsized car get a Passat, Audi or Volvo. In that order. If you want to spend a penny a mile to run your errands get a Xebra
I agree, what the Insurance Institute has always shown is, the more steel mass you surround yourself with, the safer you will be. Add in all the airbags, crumple zones and the like, it only improves what a massive steel cages does.
People can spin it in lots of ways, but a little electric car isn't going to be much protection when a Esclade runs over it. :P
Watch, we're gonna really catch heck for saying that. I'm just glad they aren't that close to me, cause I sure don't wanna be chased down by that electric cart posse, and possibly be hit by one of their canes!
I believe the study makes a valid point. By driving a larger vehicle you may be providing more safety for yourself but at the expense of the other motorist. I guess you could adopt the attitude of screw everyone else, I'm looking out for myself. The problem with that is you get in an ever escalating race to have the biggest vehicle. Would the highways be safer if we all drove 6,000 lb vehicles or 3,000 lb vehicles? Having 6,000 lbs of mass should provide for larger crumple zones but would also have a negative impact on handling. So you might have a greater likelihood of survival but also a greater likelihood of being in an accident. When I look at the insurance stats showing fatality rates in different vehicles one thing is extremely clear. The small cars with the highest fatality rates are also the cheapest cars and probably driven by the youngest drivers. The driver is the most important safety feature in a car.
Most auto and safety engineers feel that any significant advances yet to be made in highway safety will come from accident avoidance.
Duh! Both of your articles are very old 2002. Wake up and smell the coffee. You were wrong. I explained why ( 2nd laws of physics) and then proved it. While I agree that newer safety features, epecially air bags and crumple zones (passive) and (active) better tires ,bettter steering better handling, vehicle skid control, Brake force, traction control, disc brakes and ABS significantly improve the safety of smaller cars, you still can not overcome the sheer mass of a larger vehicle.
You can have your own opinion and that is fine, but scientific facts and measured objective data prove you wrong!.
The best solution large of small is to drive denfensively.
I am through discussing this subject, since apparently facts and logic are not enough! On to other EV subjects, that maybe I can discuss with those with engineering and scientific understanding or at least an open mind.
First of its not a UM study its just a physics professor stating that the way a car is built has more influence on the safety than the size of the car. In that sense he is right.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
"I explained why ( 2nd laws of physics) and then proved it."
But vehicle vs. vehicle are not the only types of accident where size (mass) plays a role.
What about vehicle vs. immovable object (abutment, tree, utility pole, etc.). In this type of accident, the vehicle structure must absorb all of the energy dissipated in the accident (since the immovable object doesn't absorb any of the energy). It is more difficult for the structure to do this when it is dealing with more mass. So, when hiting an immovable object, the smaller/lighter car has (in this case) an inherent advantage. And when you factor in (perhaps) more attention paid to crumple zone and other passive safety design features, it may well be that smaller vehicles have an advantage in this type of accident.
I have to agree with that. A thousand pounds of battery could be lethal to the occupants. I don't see myself getting into an electric vehicle and heading down the highway at 70+ MPH. Big difference in cruising around at 35 MPH the average speed in a business or residential area. Until someone comes up with a super light device to store electricity I would not consider an EV for anything but an in town runabout. That is why I think the Xebra and that genre practical. Cars like the Tesla are just a rich man's toy. I don't even like the batteries in the hybrids.
Actually you might want to look at the original article rather than referring to an article that quotes the research of Marc Ross and Tom Wentzel. The study was for a small set of vehicles from 1995 to 1999, The original article makes a lot of assumptions and statistical correlations that are not necessarily accepted industry standards and practices. Especially since the purpose of the study was to comment about the proposed legislation to raise C.A.F.E. at the time.
Actually things do change. I believe there have been significant safety features introduce since 1999.
Now getting back to EV safety, I agree that batteries are going to add weight and not provide additional structural integrity. They could have a potential advantage by being placed low under the car to lower the center of gravity. In order to compensate and to reduce the total weight, thus requiring less batteries, more stressed aluminum, lightweight alloys, and carbon fiber will be used. Also modular placement of batteries might be able to distibute the battery weight uniformly without impacting or significantly reducing the overall structural integrity.
There might be two battery sources driving EVs, one for overnight charging which would provide the main power and a 250 mile range and a second fast charge capacitive discharge or ESS that could be charge in minutes and provide a 10-15 mile range. This would get a person through emergency situations when the main batteries ran out of charge. Such things that are almost 100% efficient such as regenerative braking will also be applied to convert wasted potential energy to a battery recharge.
I guess it all comes down to what you are comfortable with. Given a choice between being in a 70 mph accident with 1000 lbs of batteries or 15 gallons of gasoline I would personally choose the batteries.
I would prefer 15 gallons of diesel. The point is there is little we can do with EV until a better source of storage emerges.
Take for example San Diego where I am currently. If I go anyplace beyond my local village I get on the freeway. It is 20 miles to downtown San Diego. That means I leave the Xebra and take one of the other vehicles. Not only that I am sure I would get pulled over driving it on Interstate 8. I am all for EVs. So far the only ones are not one car solutions. That does not mean I would not buy one. I just accept things as they are. I'm too old to try and build my own EV as a few of our fine Forum members have done.
Do you know of any reason why batteries could not be designed and positioned as to provide additional structural integrity?
I agree with your assessment that the battery pack will be distributed over the bottom of the vehicle, below the passenger compartment. Which as you pointed out will lower the center of gravity. Without a big ICE the area in front of the passenger compartment will have a lot more room for compressing in an accident.
I'm very familar with San Diego. I grew up in So. California and graduated from UCSD.
I agree that the energy storage capability of batteries is not even close to that of gasoline. To me that does not represent as big a drawback as the lack of efficiency of an ICE. Throwing a 1,000 lb battery pack into a vehicle will probably increase its net weight by 500 lbs. Carrying around an additional 500 lbs will not result in nearly the performance or fuel economy hit that occurs by using a conversion device that is only 30% efficient.
Listening to the EV detractors you get the sense that an EV needs to be at least as good as an ICE in every regard. Why? As long as it can surpass an ICE in some areas then the fact that it is deficient in others does not immediately make it inferior. Its all about priorities. For me being able to plug-in at home and never visit a gas station is extremely appealing.
Kinetic energy is directly proportional to vehicle mass. In an accident, all that kinetic energy must be shed.
In an accident involving two vehicles, the lighter vehicle will end up absorbing MORE of the energy (so, in this case your simplistic assertion that the lighter vehicle is less safe is correct).
However, in an accident involving a single vehicle and an immovable object, that single vehicle must dispel all of the kinetic energy. The higher the mass, the more kinetic energy.
"Do you know of any reason why batteries could not be designed and positioned as to provide additional structural integrity? "
What I think you will see is a more modular placement of batteries. They will not all be placed together, but rather distributed in the vehicle so as to minimize their overall affect on structural integrity. For example instead of one large battery location composed of 20(example number) modular packs, you will still have 20 modules, but their weight will be distributed and placed to be synergystic with the existing of design, modifed structure.
Okay, but even seemingly immobile objects become mobile if hit with a high enough force. My point, is that what some people consider an immobile object, really isn't when hit but a much larger force. But you are correct, and I agree with you about the dissipation of kinetic energy.
Let's take this issue of non-structural weight to the extreme. For instance, a cement truck. That big drum turning behind the truck adds no structural integrity but I suspect provides an advantage in a 2-car collision.
In an accident involving two vehicles, the lighter vehicle will end up absorbing MORE of the energy (so, in this case your simplistic assertion that the lighter vehicle is less safe is correct).
That would depend on how each vehicle is designed to absorb and direct that energy.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
While only 36% of the miles are driven within 25 miles a majority of car accidents occur within 25 miles. So buying a EV as a rural vehivcle only and thinking you will be safer from traffic accidents, just isn't statistically true. That was the original point when someone said they would get a EV as a rural transport and wouldn't go out on the highway because it would be safe on the highway.
Comments
I agree flexibility in battery placement can be an advantage. In both handling and interior/exterior design.
I have jumped on the EV bandwagon because it seems the technology is here or very near to make a normal car at a normal price. I am sure some folks want a Zebra, personally when you can get an Aveo for a close price point, I can't find much reason for the zebra...unless I lived in some sort of closed community or a farm or such.
I would buy a Xebra for the previous stated reasons. I would never even consider owning or renting an Aveo sized car. They are of no more value for running errands and they cost 10 times as much to operate. I believe they should be restricted to surface streets as the Xebra will be. Higher cost to own the Aveo, Yaris & Fit. Besides they are also ugly with no socially redeeming values.
I cannot say for certain that the Xebra will be practical for the long haul. They use relatively cheap lead acid gel cells. What else is there to replace? Plus I never have to wait in line for gas or oil change.
That seems to be a popular criticism of EVs, that they don't make sense from a purely cost perspective. I'm not sure if that is always true. Even if it is true that doesn't mean that they couldn't be marketable. Does a BMW make sense from a cost perspective? Probably not but people assign intangible value to things like style and status. The same would be true for EVs. Driving an EV will be a chance to make a personal statement regarding the oil industy, energy independence, OPEC, pollution, etc.. This holds a lot of value for some people.
Thanks for the update, WOW prius is a hybrid that runs off both gasoline and batteries. Does that man the golf courses can no longer use them???
Thanks,
MidCow
Basic Physics 3500 sedan will samsh a 2000 EV
Try pounding a nail in a board with your finger!
MidCow
If you want to talk physics please put in those safety features such as airbags and crumple zones.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
Saving money is the principal reason I drive an EV. EVs are considerably cheaper from an operating cost standpoint, both for fuel and maintenance. This is a major plus for EVs, and this story needs to be told.
Principal costs to worry about are initial purchase price and battery replacements. Driving an EV conversion solves both these problems. These cars, for instance:
http://grassrootsev.com/convert.htm
Are reasonable to purhase, and old lead-acid battery tech is not expensive. Less than $1000 every 20,000 to 30,000 miles, or about 4 cents per mile. Electricity for driving is only about 1 cent per mile, so total operating cost is very close to 5 cents/mile. (Almost no additional maintenance is needed.)
Li-Ion batteries can meet similar cost targets as lead-acid. Example: look at the price/watt of these Chinese EV batteries (these are available in the USA):
http://everspring.net/product-battery.htm
As for production models, EVs do not need to sport high purchase prices. But if we must accept that they will for the time being (because of low manufacturing volume), consider that a fairly typical driver could save close to $200/month in gasoline costs. Subtract the fuel savings from your EV's monthly loan payment, and this makes the EV just as affordable as a car with a $10,000 lower price tag.
Funny how two people reading the same post can see it sooo differently.
But there is no $20K EV Yaris with a 100mi range, nor will there be with the technologies currently known!
More than a decade ago, my employer (an electric utility) was promoting Geo Metro EV conversions selling for $25k+ when a standard Metro could be had for <$10k. Needless to say, they were unsuccessful. As compared to the standard Metro, the EV had space for but 2 people, was underpowered, grossly overweight and had much less than 100mi range (~70 IIRC). The EV was comparable to the standard metro in outward appearance only! Improvements to batteries since then might improve performance and utility slightly while raising price dramatically. Dreaming won't make it so.
Interesting choice of words. Li-ion batteries store 4x the energy per kg as the lead acid batteries in that Metro EV. So in your mind this "might" provide a "slight" improvement in performance and utility. I'd say that is a pretty good bet.
A company called Miles Motors will be importing a Chinese EV next year called the xs200. Top speed of 80 mph and a range of 200 miles. Costs $28,500. That's a pretty good price when you consider that to achieve this range it must have around a 50 kWh battery pack. The 27 kWh battery pack on the Rav4 EV cost $27k to replace.
Just isn't possible to defeat the laws of physics. Newton stated this relationship in his second law, the force of an object is equal to its mass times its acceleration. You can attempt to lessen it with automatic locking seatbelts, dual level airbags, impact absorbing interiors, electronic stability control, ABS, vehicle skid control, crash resistant door pillars, crumple zones, break away components, SRS, side curtains , etc. But the bottom line is you can't defeat Newton's second law.
Be Safe,
MidCow
We are not trying to defeat any laws of physics but understand them in order to work them to the best interest of those riding in the car.
Again you can make a lighter car safer than a heavier car by making certain adjustments to it. To say otherwise means that all the safety advances in the last 120 years are for naught.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
Here are two good 1955 Buick web sties. They are nostalgic, that is if you are old enough to remember
http://www.55buick.com/production_figures.html
http://www.55buick.com/
Drive your small car carefully,
MidCow
P.S. - the last 120 years of safety; now you are talking aboutcars in 1886. Now all credibility is lost . What safety features did Fulton's steam engine have ?
Eventually, it will sink in why battery energy/power density is the EV achilles heel.
Search on "Colt EV." You will find just that.
And higher maintenance costs, higher fuel costs, higher pollution are the achilles heels of the ICE.
http://www.theautochannel.com/news/2002/09/12/147283.html
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
http://www.iihs.org/brochures/ictl/ictl_4dr.html
People can spin it in lots of ways, but a little electric car isn't going to be much protection when a Esclade runs over it. :P
Watch, we're gonna really catch heck for saying that. I'm just glad they aren't that close to me, cause I sure don't wanna be chased down by that electric cart posse, and possibly be hit by one of their canes!
Most auto and safety engineers feel that any significant advances yet to be made in highway safety will come from accident avoidance.
You can have your own opinion and that is fine, but scientific facts and measured objective data prove you wrong!.
The best solution large of small is to drive denfensively.
I am through discussing this subject, since apparently facts and logic are not enough! On to other EV subjects, that maybe I can discuss with those with engineering and scientific understanding or at least an open mind.
MidCow.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
Duh facts do not change with age.
You can have your own opinion and that is fine, but scientific facts and measured objective data prove you wrong!.
Actually they have proven me right. A small car of today is much safer than a big car from the 50's or 60' or 70's....
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
But vehicle vs. vehicle are not the only types of accident where size (mass) plays a role.
What about vehicle vs. immovable object (abutment, tree, utility pole, etc.). In this type of accident, the vehicle structure must absorb all of the energy dissipated in the accident (since the immovable object doesn't absorb any of the energy). It is more difficult for the structure to do this when it is dealing with more mass. So, when hiting an immovable object, the smaller/lighter car has (in this case) an inherent advantage. And when you factor in (perhaps) more attention paid to crumple zone and other passive safety design features, it may well be that smaller vehicles have an advantage in this type of accident.
(this is an EV thread)
MidCow
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
Original: http://www.uctc.net/access/access21lighter.pdf
Actually things do change. I believe there have been significant safety features introduce since 1999.
Now getting back to EV safety, I agree that batteries are going to add weight and not provide additional structural integrity. They could have a potential advantage by being placed low under the car to lower the center of gravity. In order to compensate and to reduce the total weight, thus requiring less batteries, more stressed aluminum, lightweight alloys, and carbon fiber will be used. Also modular placement of batteries might be able to distibute the battery weight uniformly without impacting or significantly reducing the overall structural integrity.
There might be two battery sources driving EVs, one for overnight charging which would provide the main power and a 250 mile range and a second fast charge capacitive discharge or ESS that could be charge in minutes and provide a 10-15 mile range. This would get a person through emergency situations when the main batteries ran out of charge. Such things that are almost 100% efficient such as regenerative braking will also be applied to convert wasted potential energy to a battery recharge.
Cheers,
MidCow
Take for example San Diego where I am currently. If I go anyplace beyond my local village I get on the freeway. It is 20 miles to downtown San Diego. That means I leave the Xebra and take one of the other vehicles. Not only that I am sure I would get pulled over driving it on Interstate 8. I am all for EVs. So far the only ones are not one car solutions. That does not mean I would not buy one. I just accept things as they are. I'm too old to try and build my own EV as a few of our fine Forum members have done.
I agree with your assessment that the battery pack will be distributed over the bottom of the vehicle, below the passenger compartment. Which as you pointed out will lower the center of gravity. Without a big ICE the area in front of the passenger compartment will have a lot more room for compressing in an accident.
I agree that the energy storage capability of batteries is not even close to that of gasoline. To me that does not represent as big a drawback as the lack of efficiency of an ICE. Throwing a 1,000 lb battery pack into a vehicle will probably increase its net weight by 500 lbs. Carrying around an additional 500 lbs will not result in nearly the performance or fuel economy hit that occurs by using a conversion device that is only 30% efficient.
Listening to the EV detractors you get the sense that an EV needs to be at least as good as an ICE in every regard. Why? As long as it can surpass an ICE in some areas then the fact that it is deficient in others does not immediately make it inferior. Its all about priorities. For me being able to plug-in at home and never visit a gas station is extremely appealing.
Agree 100%.
Well actually that isn't true; only about 36% of the miles are driven in rural. Look at the DOT 2005 traffic study, specifically page 50. http://www.wsdot.wa.gov/mapsdata/tdo/PDF_and_ZIP_Files/Annual_Traffic_Report_200- - 5.pdf
Which makes sense if you think about because there are 44,000 miles on highways across the USA.
So if a person drives an EV runabout in the rural area, they might not be as safe on a per mile driven basis.
MidCow
Just simple physics.
Kinetic energy is directly proportional to vehicle mass. In an accident, all that kinetic energy must be shed.
In an accident involving two vehicles, the lighter vehicle will end up absorbing MORE of the energy (so, in this case your simplistic assertion that the lighter vehicle is less safe is correct).
However, in an accident involving a single vehicle and an immovable object, that single vehicle must dispel all of the kinetic energy. The higher the mass, the more kinetic energy.
"Do you know of any reason why batteries could not be designed and positioned as to provide additional structural integrity? "
What I think you will see is a more modular placement of batteries. They will not all be placed together, but rather distributed in the vehicle so as to minimize their overall affect on structural integrity. For example instead of one large battery location composed of 20(example number) modular packs, you will still have 20 modules, but their weight will be distributed and placed to be synergystic with the existing of design, modifed structure.
MidCow.
Okay, but even seemingly immobile objects become mobile if hit with a high enough force. My point, is that what some people consider an immobile object, really isn't when hit but a much larger force. But you are correct, and I agree with you about the dissipation of kinetic energy.
MidCow
Well actually that isn't true; only about 36% of the miles are driven in rural."
What in the heck does one have to do with the other? :confuse:
Well actually that isn't true; only about 36% of the miles are driven in rural.
Well since a majority of the population doesn't live in rural areas I am not surprised that less than 36% of the driving is done on rural roads.
Which makes sense if you think about because there are 44,000 miles on highways across the USA.
I do believe the interstate system is 44,000 miles I do believe that it is something like 4 million miles of roads in the USA.
I restate that the reason most accidents happen within 25 miles of home is the fact that most driving is done within 25 miles of home.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
That would depend on how each vehicle is designed to absorb and direct that energy.
2011 Hyundai Sonata, 2014 BMW 428i convertible, 2015 Honda CTX700D
While only 36% of the miles are driven within 25 miles a majority of car accidents occur within 25 miles. So buying a EV as a rural vehivcle only and thinking you will be safer from traffic accidents, just isn't statistically true. That was the original point when someone said they would get a EV as a rural transport and wouldn't go out on the highway because it would be safe on the highway.
MidCow