CA Cars, your thoughts?

[vab]

just wondering what some of the people here think of when they read about the Compressed Air vehicles being made over in india. i myself think that it is a great idea and im wondering why it wasn't implemented into everyday transportation sooner.

[CaptainPanic]

For short and perhaps medium range trips I see no problems with the compressed air car. It is a good solution for city traffic, and it reduces the pollution.

 

But I am still skeptic about its overall efficiency (including the compression of the air in "compressed gas stations"). Perhaps the air can be compressed by using the much cheaper coal, rather than using oil for the fuel, which will give an economic benefit.

 

I haven't done any calculations, and I don't intend to do any in the near future, but if anyone has a link or back-of-the-envelope calculation to show these things are at least as (overall) fuel efficient as combustion cars.

 

Personally, I favor the option of the battery + electric engine.

[insane_alien]

Compressed air cars are all well and good but there is whole lot of BS surrounding them, like there are no CO2 emmisions, well, from the car theres not but from the powersource for the air pump to compress the air i bet there will be.

 

They are analogous to battery powered vehicles and hydrogen fueled cars. They are a good interim till we get a decent hydrogen storage system or super battery/capacitor.

[D H]

Compressed air cars are all well and good but there is whole lot of BS surrounding them, like there are no CO2 emmisions, well, from the car theres not but from the powersource for the air pump to compress the air i bet there will be.

Especially if the power comes from cheap but inherently dirty (in terms of CO₂) coal.

 

They are analogous to battery powered vehicles and hydrogen fueled cars. They are a good interim till we get a decent hydrogen storage system or super battery/capacitor.

How much pollution is involved in creating batteries? I have read that solar cells are quite nasty for the environment if you add in the amount of water, power, and toxic chemicals needed to mine the materials and produce the solar cells. Are batteries "clean" or do they just appear clean?

[CaptainPanic]

D H, off topic as it may be, do you have a link or reference to the place where you read about the solar cells?

(Personally I always thought that all the pollution actually goes into the cells... rather than being dumped somewhere... of course, this only postpones the problem to the day that the solar cell becomes waste itself).

[D H]

The dark side of solar cells

 

Making solar cells requires sand, which must be mined; heavy metals for doping, which must be mined and which are particularly nasty to the environment when released; lightweight metals, which must be mined and refined; toxic chemicals for photoetching; lots of water; and lots of electrical power.

 

Until recently, more power went into making solar cells than the cells produced during twenty years of operation. Huge amounts of water are used to make solar cells. The chemicals used in the manufacturing process are very, very nasty. Dealing with spent solar cells will be another problem if they become ubiquitous. While using solar cells is a clean process, what happens before and after the cells are used is anything but clean.

 

The bright side

 

A recent study indicates that solar cells are in fact considerably greener than conventional coal-based power generation, even after taking manufacturing into account. One article on this research is at Scientific American. You can find more (same study, however). I hadn't heard of this study until you asked, and it is all over the web.

 

Further reading

 

On the dumping of toxic wastes from solar cell manufacturing in China: http://www.washingtonpost.com/wp-dyn/content/article/2008/03/08/AR2008030802595.html

 

On the efficacy of solar cells: http://www.alphagalileo.org/index.cfm?fuseaction=readrelease&releaseid=519886&ez_search=1

[danie]

I think it is brilliant

 

My view is that you must be able to produce the energy for transport in your own backyard ( solar and wind) The big problem is energy storage and energy density. You can use a windmill to compress the air and solar panels for charging batteries. The problem with transport is the weight of the car. You dont nead a1 ton car to transport you from point A to B .

Hopefully they will take that into account in the future

[DJBruce]

It is just another quick fix in my opinion. The energy need to compress the air will more than likely come from fossil fuels. So really I see no real benefit.

[booker]

Thermal energy is lost in compression, and later, decompression, upon use. I wonder what the efficiency figures are on this...

 

The fluid heats upon compressing into the tank. After a time it reaches thermal equalibribum with ambient, say. As this happens the pressure drops a bit.