Research conducted by the Business Research Travel Centre at Cranfield University concluded that the carbon emissions level from first-class folk could be as much as double that of those in standard-class. Their research focuses on aviation, though their findings can be directly applied to trains.
Having identified the formula, named 'Real Estate Calculation' (REC), comprised by looking at first-class passengers' average space occupied, actual load factors and food consumed, placed figures on each class of traveller on trans-Atlantic flights between North America and Europe.
First-class rail travellers have more leg room - the seating herein generally aligned to windows; receive some level of complimentary food; often have seats that are able to recline and so cannot be as near to other seats - and these seats weigh a lot more; and Cranfield Uni students even said that the weight of the food trolley could be added to the REC as it would be likely to make more journeys per flight/journey through the first-class section.
The Business Travel Research Centre's Director, Keith Mason, said "If a company is interested in trying to minimize their carbon foot, maybe that company shouldn't be flying in first class as much of the time. In this case, money and environmental costs go hand in hand.''
Carbon offsets are generally offered by airlines, so that passengers can pay for their estimated negative contribution to the world. Train operators generally do not offer anything along these lines; in the current climate of increased fares amidst a (perceived?) lack of improvements to frequencies and capacities, such a scheme would not prove popular at all!!
Trains are more environmentally friendly than planes and therefore you could deduce that any REC would be proportionately reduced, too. Should first-class rail passengers be concerned? After all, there's no such thing as an electric Boeing 737!
Can a first-class traveller aboard a First Capital Connect (FCC) train, travelling from King's Lynn to London King's Cross really be considered to have a larger carbon footprint to the same commuter in standard class? FCC do not offer a trolley service, nor do they afford their first-class passengers any gratuity. They simply offer slightly better leg-room at designated seating. Their trains are also far cleaner than any train requiring diesel to fuel its engine as its fleet is needs nothing more than electricity.
You could then take things to another level by asking how the electricity is generated to enable FCC's fleet to move, and to what extent this is affecting passengers' carbon footprints. After all, a ten-carriage train full of first-class seating will hold fewer passengers than one with only standard-class accommodation. (GL)