There is a major difference between cars and plants, and it's the driving factor behind the "green" trends in the automotive industry today. By nature, plants absorb carbon dioxide from the atomsphere, and release oxygen. This is good. This is how the ecosystem is supposed to work. Plants like this. Human bodies like this. In contrast, petroleum burning vehicles consume oxygen during combustion and emit carbon dioxide into the atmosphere. Now if you're thinking, "wait, that's great--everything will balance out right?", you're partially correct (Rremember, humans consume oxygen and emit carbon dioxide too). The problem is, too much of a good thing is not such a good thing in this case. Specifically, automotive carbon emissions are at a level determined to be unhealty for the environment in general. For this reason, automakers and government organizations have been focusing heavily on reducing the amount of carbon dioxide emissions produced by motor vehicles.
So far, the best examples of green cars have managed to eliminate emissions. Hydrogen fuel cell and plug-in electric vehicles boast zero emissions. These technologies are becoming a reality right now, but the Shanghai Automotive Industry Corporation (SAIC) of China has gone a step further with a concept that acually consumes C02, rather than emitting it! Although the technology isn't quite ready to hit the streets, SAIC says it's real, and will be available 20 years from now. It's hard to imagine what automobiles will be like 20 years from now, but this might be a sneak peak.
Here's how the YeZ works. A photoelectric converter is incorprated into the car's leaf-shaped canopy, and collects energy from the Sun. This energy is converted to electricity, which powers a fully electric drivetrain. Wind power is even harvested from small windmills on all four wheels. And I thought spinners went out of style years ago!
The vehicle's body is constructed with metal-organic framework materials which absorb water and carbon dioxide (yes, this is the negative emissions bit). The YeZ then does three really cool things with the two naturally occurring resources. It generates electricity, air conditioning refrigerant, and... oxygen! The oxygen is diffused back into the air, where it should be. This process makes it the most plant-like car concept yet!
This revolutionary project has set the bar very high for green vehicle development. It will take baby steps from automotive manufacturers to fully achieve something like this over the next couple of decades, but lofty goals have the potential of inspiring incredible designs. I'm looking forward to seeing how others respond with similar proof of these capabilities, or alternative methods to reach the same goals.