This is a major interest for me as well. From what I know, sustainability investors are looking for companies in some of the following categories globally:
Companies who have a strong sustainability roadmap which is global and long term: Walmart and Unilever come to mind - even though their products, packaging, etc is nowhere near green as of now.
Companies who are doing triple bottom line accounting where environmental and social impact is also given a preference
Companies who have actual green or alternative products e.g. solar, LEDs (?), jute, organic food etc that you mentioned.
Coming to the Indian markets, apart from the sustainability mantra percolating to MNCs from their HQ, and some preliminary or naam ke waste initiatives (e.g. Godrej's green building initiative, or sustainability reports of Wipro, etc), I have NOT seen any major thrust on green from any Indian companies.
Yes, companies are trying to be energy efficient and reduce carbon footprint, but I know of no company that does extensive carbon accounting and aggressively tries to reduce it.
Would love to keep exchaging notes on this.