Note: Picture is unrelated. Just like my girlfriend and I.
Will glowing trees replace streetlights? I doubt it. Still, you never know. If you'd asked me ten years ago if we'd have hover cars by now I'd have been all, "oh hell to the yes we will!" But look around -- what do you see? Exactly, a big box of sadness. Anyway, nanoparticulated glowing tree "streetlights". I imagine birds aren't thrilled about the idea.
Dr Yen-Hsun Su from Taiwan's National Cheng Kung University discovered that when you add gold nanoparticles to the leaves of Bacopa caroliniana, it induces a red emission in the chlorophyll. Bacopa caroliniana is a plant widely found in the Southern US, but the same reaction might be possible in other plants and trees. Dr Ye-Hsun points out that this is potentially a win-win-win situation, with the glowing plants reducing power usage, and lowering light pollution, while absorbing CO2.
While injecting certain trees with gold nanoparticles to make them glow does sound like a pretty foolproof plan, here's another: solar-powered streetlights. They may not absorb CO2, but I will continue to shoot the one outside my bedroom window with a BB gun until they stop replacing it.