Hey Akhilesh,
Welcome to the group.
Quick notes and feedback from personal perspective -most of which you already may have thought of:
* I know a guy in Delhi whom I'd helped refine aspects of a similar idea
to build a business around it. If you want, I can try and reconnect
with him
* Your idea to launch on a small scale first is very smart. Every thing needs to be done in stages, gather info, and refine for a larger audience
* I'm not a big fan of completely free things. Keep it nominal, but charge something. That way you become self-sustainable and keep bothersome people away
* End user doesn't care of reducing carbon footprint. He needs a good solution. These numbers are important, but they should drive your decisions and not be projected to the end users as primary distinguishing feature of your product
* Thinking about donating the earnings to orphanages is nice, but you can't not make money and keep it sustainable (Aah, my love for double negatives)