Plenty of fuss has been made over whether or not carbon fiber, EV batteries, etc. are eco-friendly. The argument in favor of or against certainly won't be put to rest here.
Here's what BMW's Klaus Draeger, head of purchasing has to say on this topic in regards to the BMW i3:
“If you take together the battery, the carbon fiber, the aluminum and what is on the car, you start slightly worse than a conventional car."
“But by using much less energy during driving, the carbon emissions over the lifetime of an i3 is better than a conventional car…and if you drive the car during the lifespan with renewable energy it is actually much better."
Focusing only on the carbon fiber for the BMW i3 and i8, Ward's Auto states:
"...the automaker plans to use all 9,000 tons (8,165 t) of carbon fiber annually set to come from SGL in Moses Lake."
"Our prognosis currently shows that we will need all this we are producing here. But, of course, if there were to be some overcapacity, we could think about (sales to other automakers) as well.”
Check out the Ward's Auto article at the link below for more in-depth analysis on the carbon fiber used in the BMW i3.
Source: Ward's Auto