The term 'flare' actually refers to the burning of the gas...

The term 'flare' actually refers to the burning of the gas produced, rather than burning of coal. It is a term widely used in the petroleum industry, and whilst that fact may not be known widely, I agree it might impact on peoples' perception.

As for a commercial UCG operation, I don't think there is a commercial site running. Without looking further, Swan Hill were operating a trial in Canada, GCL in China were active, but I think morphed into a solar panel play and have gone bankrupt. I'm sure a search would just run straight to Linc and Carbon Energy!