the other day, I was learning basic bio tech(of 10th grade) .. and found out about genetic engineering. So what I thought was .. there are these bioluminescencent(light giving) organsisms in the deep sea and in trees too(fire flies!) which must be having some or the other gene to make them produce light. So why not introduce this gene into roadside trees and make them as streetlights? Then no electricity waste (and though street lights are run on solar panels silicon or other metalloids are wasted here)... instead there will be a multi-benefit of more trees , oxygen , rain ....etc. This is just what I believe might be possible... please be free and correct me if I am wrong.