I am writing this post from Goa, on the West coast of India. I flew here from Manchester, in the premium economy section of a Tui Boeing 787 Dreamliner. 

According to the ICAO carbon calculator [1] the aircraft will have burned 54 tonnes of fuel on each leg of the journey, which equates to 654kg of CO2 per passenger (2x the standard economy emissions due to the “premium” cabin seating). The plane was full, so I think the calculations are reasonable and, while I could argue that “premium economy” is not really twice the space or mass of standard economy, I don’t quibble with the figures.