'Green Cars'

[Factory]

What are your views towards electric cars? They are advertised as 'green' due to a much lower consumption of fossil fuels. However, in order to create the batteries for these cars, there has been a massive spike in rare earth mining in more recent years. The processes that yield these rare earth elements are not green at all. They utilize diesel machinery, a plethora of chemical agents for refining, and do it in such a way that it is non-sustainable. Mind you, the majority of REEs come from China as well, where they are even more lax in regards to both protecting the environment and protecting the workers.


I personally believe that the concept of these vehicles is an excellent one, but the current processes taken to create them do not really help the environment at all. Instead the extent of damage to the environment is just shifting hands, from the car owners to the people mining these resources.

Of course, rare earth elements go into many other devices, such as phones, tablets, surgical equipments, but a large amount of demand recently has been due to this notion that green cars are actually green.


Share your thoughts.

[myrkul]

Well, given that electricity can be generated in ways that do not harm the environment (check out LFTR), yes, I think electric cars have a great potential for benefiting the environment, especially if sustainable rare earth minerals mining is more widely used.

[FirstAscent]

This car is greener than most, as it's a real 200+ mpg, as opposed to the bullshit mpg calculated for plug-in hybrids such as the Volt.

http://www.roadandtrack.com/future-cars/spy-photos/caught-testing-2014-volkswagen-xl1/

To me, a real green car would be tandem seating (one in front, one in back) to halve the frontal surface area, real aerodynamics (no concessions to fashion and looks), extreme lightweight allowing narrower tires, which in turn reduces road friction, and the lightweight simply reduces acceleration costs as well, and finally, regenerative breaking. Combine all this with motors receiving their electricity from hydrogen fuel cells, and your exhaust is water vapor. The compressed hydrogen, should in turn be produced from the ocean in the most environmentally friendly manner. All methods of electricity generation are fraught with problems, so a true analysis of the best is important. We can rule out hydroelectric, as dams should just be destroyed, period.

[benjamindees]

Because of the low energy density of batteries, electric cars aren't actually much more efficient than internal combustion automobiles.  They are cheaper to operate because coal is cheaper than oil.  So unless they use nuclear or renewable energy, they aren't particularly 'green'.

[Grouver (BtcBalance)]

On a sidenote: Regarding peak Oil and alternative energies people should watch: "The Collapse".
In his opinion cars are gonna be history and only for the rich when the oil is gonna start to be scarce.
"There not gonna be 800 million new electric cars. Cause there ain't gonna be enough oil."

Also, electricity isn't a source of energy, it's a way of transporting energy from where it's generated to where it's used.

In a car (as we know it now) oil is needed for:

-Electronics
-Varnish
-Paint
-Tires
-Plastic parts
-Motor oil



Of course there parts that are not excist out of oil.
But the making of them is a energy intesive proces and does cost alot of oil.

-Making of the steel.
-Making of the glass.
-Making of the stuff that excists out of oil in general.

And do not forget the shipping around to your car dealer will cost alot of oil.
And of course i will have forgot something. But these lists are just to get an idea.

[Shadow383]

Anyone who thinks hybrids are better for the environment has never seen the amount of toxic waste that gets chucked into rivers due to lithium mining. In addition to which there's the extra fossil fuels used in making those cars - Top Gear in the UK got the stats together and worked out that due to the extra fuel involved in producing/shipping all of the parts around the world, a prius doesn't get more economical than a range rover until it's done about 90000 miles.
By that time it probably needs a new battery anyway 

That Volkswagen looks interesting though. Not a fan of the skinny tyres but as an aerodynamicist I have to say it looks pretty reasonable. Back's still not perfect though and they could probably improve it a few percent with wheel covers.

[herzmeister]

* Ford's hemp car (article)
* Ford's hemp car (youtube)

[FirstAscent]

That Volkswagen looks interesting though. Not a fan of the skinny tyres but as an aerodynamicist I have to say it looks pretty reasonable. Back's still not perfect though and they could probably improve it a few percent with wheel covers.

Skinny tires are preferable due to less road friction. They provide the same traction as fatter tires if you reduce the weight of the car. Double win: less road friction and less weight = same traction but allows for two factors which are increasing efficiency.

[Shadow383]

That Volkswagen looks interesting though. Not a fan of the skinny tyres but as an aerodynamicist I have to say it looks pretty reasonable. Back's still not perfect though and they could probably improve it a few percent with wheel covers.

Skinny tires are preferable due to less road friction. They provide the same traction as fatter tires if you reduce the weight of the car. Double win: less road friction and less weight = same traction but allows for two factors which are increasing efficiency.

Wider tyres + Lower weight = Better traction 

For the few percent you save I'd rather have a car that can brake and turn extremely well. The 3-5% you might get on fuel efficiency seems tempting, but believe me when you've just hit someone's bumper/dog/child it won't seem like such a great idea.

[FirstAscent]

That Volkswagen looks interesting though. Not a fan of the skinny tyres but as an aerodynamicist I have to say it looks pretty reasonable. Back's still not perfect though and they could probably improve it a few percent with wheel covers.

Skinny tires are preferable due to less road friction. They provide the same traction as fatter tires if you reduce the weight of the car. Double win: less road friction and less weight = same traction but allows for two factors which are increasing efficiency.

Wider tyres + Lower weight = Better traction  

*sigh*

Take any car on the road that satisfies your traction requirements. Cut its weight in half. You now gain efficiency due to less weight. Now reduce the tire's width until it has the same traction as the original heavier car. You now gain efficiency due to less road friction.

Double win.

Furthermore, the less weight means you'll stop quicker and won't hit that bumper/dog.

Triple win.

Furthermore, you can gain even more efficiency if you increase the diameter of the wheels/tires significanctly, due to what is know as the angle of attack.

Automobiles need to be rethought. Unfortunately, everyone has expectations about what a car is supposed to look like.

[FirstAscent]

Back's still not perfect though and they could probably improve it a few percent with wheel covers.

http://www.google.com/search?q=volkswagen+xl1&hl=en&prmd=imvns&tbm=isch&tbo=u&source=univ&sa=X&ei=05ciUJLdEKLI2gW8p4CgBg&sqi=2&ved=0CF8QsAQ&biw=1156&bih=1027

[Fiyasko]

That Volkswagen looks interesting though. Not a fan of the skinny tyres but as an aerodynamicist I have to say it looks pretty reasonable. Back's still not perfect though and they could probably improve it a few percent with wheel covers.

Skinny tires are preferable due to less road friction. They provide the same traction as fatter tires if you reduce the weight of the car. Double win: less road friction and less weight = same traction but allows for two factors which are increasing efficiency.

Wider tyres + Lower weight = Better traction 

For the few percent you save I'd rather have a car that can brake and turn extremely well. The 3-5% you might get on fuel efficiency seems tempting, but believe me when you've just hit someone's bumper/dog/child it won't seem like such a great idea.

Your a fool, Take a 1lb car, With whatever fucking bigwide wheels you want, And you wont even beable to drive with all that spinning out you'll be doing.
YOU NEED WEIGHT TO APPLY POWER TO THE ROAD

Could someone just slap down the laws of math that show how "traction" works? so that we dont have a bunch of stupid bickering over tires.
were trying to talk about ecenomical effeciency for the enviroment by building electric(style) cars

[silvertree]

* Ford's hemp car (article)
* Ford's hemp car (youtube)

Now thats what i call a green car

[Shadow383]

That Volkswagen looks interesting though. Not a fan of the skinny tyres but as an aerodynamicist I have to say it looks pretty reasonable. Back's still not perfect though and they could probably improve it a few percent with wheel covers.

Skinny tires are preferable due to less road friction. They provide the same traction as fatter tires if you reduce the weight of the car. Double win: less road friction and less weight = same traction but allows for two factors which are increasing efficiency.

Wider tyres + Lower weight = Better traction 

For the few percent you save I'd rather have a car that can brake and turn extremely well. The 3-5% you might get on fuel efficiency seems tempting, but believe me when you've just hit someone's bumper/dog/child it won't seem like such a great idea.

Your a fool, Take a 1lb car, With whatever fucking bigwide wheels you want, And you wont even beable to drive with all that spinning out you'll be doing.
YOU NEED WEIGHT TO APPLY POWER TO THE ROAD

Could someone just slap down the laws of math that show how "traction" works? so that we dont have a bunch of stupid bickering over tires.
were trying to talk about ecenomical effeciency for the enviroment by building electric(style) cars

It's not exactly difficult maths to work out that a greater contact patch is capable of producing greater friction (and hence greater lateral load for example).
Yes you end up with less traction per unit surface area of the contact patch due to lower loading on each section, but under real-world conditions with real materials the relationship is non-linear (whereas the increase in lateral load due to excess weight is) and as a result you're better off with the greatest possible contact patch area (read - wider wheels) on a dry surface.

The only situation where this isn't true is on a wet surface, as a wider tyre will be less likely to dig in, particularly if the tread blocks are quite large.
This is also why rally snow tyres are typically very narrow.

Yes, weight helps you put down power, but with the right suspension and tyre setup any road car can realistically be manageable. Besides, I don't think "MOAR POWER" is the aim of "green" vehicles  I very much doubt you'll be drifting a 235Mpg VW in the dry 

[DannyHamilton]

Your a fool, Take a 1lb car, With whatever fucking bigwide wheels you want, And you wont even be able to drive with all that spinning out you'll be doing.
YOU NEED WEIGHT TO APPLY POWER TO THE ROAD

I'm not sure this is true.  Mass (what you are calling weight) occurs in equal amounts in both parts of the equation.

In the case of the friction needed to transfer power to the road, the force of gravity on that mass (actual weight) provides the normal force component of the equation (Friction = Coefficient of friction times the normal force). Normal force = mass times the acceleration provided by gravity.

Acceleration of the vehicle is directly dependent on mass as well (Acceleration = Force, provided by the friction against the road, divided by mass)

Since mass is in both the numerator and the denominator of the Acceleration (in the numerator as the mass component of the friction force) in equal amounts, they should cancel out.

In other words, that 1lb car doesn't need nearly as much power applied to the road to get the same acceleration because it doesn't need to accelerate nearly as much mass.  You reduce the power that you attempt to apply to the road until you get to the same acceleration as the heavy car, and you find that the wheels don't spin out at all.

[DannyHamilton]

It's not exactly difficult maths to work out that a greater contact patch is capable of producing greater friction . . . a wider tyre will be less likely to dig in, particularly if the tread blocks are quite large. . .

As far as I know there isn't any area of contact patch in any of the friction equations.  Friction is typically coefficient of friction times the normal force.  As you point out, the tread pattern and shape of the tire can influence the coefficient of friction by influencing the percentage of tire surface that is contacting wet, or dirty, or oily, or clean, or dry pavement.  Assuming clean, dry, consistent road surface the size of the contact patch shouldn't effect traction/friction.

[DannyHamilton]

. . . hybrids are still using the godawfull inefficient piston engine . . .

Technically this may be true, but there are so many different hybrid technologies out there that you have to be careful about tossing them all in together and discussing them as though they don't have differences.

As an example, while the Toyota HSD does use a gasoline burning internal combustion piston engine, it does not use the Otto cycle engine that most modern vehicles use.  Instead it uses a modified Atkinson cycle where the the power stroke is essentially longer than the compression stroke.  This makes for an engine that is significantly more efficient than the "godawfull inefficient piston engine" of most vehicles.

[Fiyasko]

-

-

-

-

It's not exactly difficult maths to work out that a greater contact patch is capable of producing greater friction (and hence greater lateral load for example).
Yes you end up with less traction per unit surface area of the contact patch due to lower loading on each section, but under real-world conditions with real materials the relationship is non-linear (whereas the increase in lateral load due to excess weight is) and as a result you're better off with the greatest possible contact patch area (read - wider wheels) on a dry surface.

The only situation where this isn't true is on a wet surface, as a wider tyre will be less likely to dig in, particularly if the tread blocks are quite large.
This is also why rally snow tyres are typically very narrow.

Yes, weight helps you put down power, but with the right suspension and tyre setup any road car can realistically be manageable. Besides, I don't think "MOAR POWER" is the aim of "green" vehicles  I very much doubt you'll be drifting a 235Mpg VW in the dry 

Very correct!
But surely they've got the car wheels designed for tarmac/pavement. And yeah no, I dont think you can even drift this car on solid ground , On that note i wonder how well it would perform on sand

[dunand]

* Ford's hemp car (article)
* Ford's hemp car (youtube)

Wikispeed and Silkroad can team up to develop a hemp car. 

[myrkul]

* Ford's hemp car (article)
* Ford's hemp car (youtube)

Wikispeed and Silkroad can team up to develop a hemp car. 

Now that would be a "green" car.