Coal powered diesel generators? At least they may get a discount on some ACME carbon credits. A totally owned subsidiary of algore carbon credit emporium and marijuana shops inc, LLC.
Actually, diesel engine have been powered by coal. The compression temperatures are high enough to ignite powdered coal injected into the cylinders.
The point I am making, though is that there isn't enough used cooking oil to power the world, and coal powered electricity is likely to be used at the meeting, as well.