Cow dung I believe.
Interesting point. Incidentally cow dung and other agri waste, which is generally burnt and causes a lot of pollution can be converted into bio gas very efficiently. If India could utilise the dung and biomass which is currently being wasted and convert into bio gas it could generate 60 million MT of LNG equivalent (or 210 million cubic meters of gas per day). India has already started a project which hopefully in 3-4 years time generate 15 million MT of Bio CNG. While I dont have similar numbers for Pak, since its agricultural output is about one fifth of India's safely we can assume a potential of 10 million MT plus.
Issue is that biogas is a bit expensive- it costs around Rs 55/kg- it is economical if crude prices are above USD70 or so, else it is costlier. My view is that both India and Pak should go for it. Even if expensive it saves a huge amount of forex, plus most of the money will go to farmers and workers rather than Arab sheikhs.
Any views-
@niaz @VCheng @Wood @Clutch @nahtanbob and other learned Maulaners here?
Regards