Thank you for those figures. I wonder how much the difference would be to compare say a Bulleid Pacific with an Austerity?
Steaming fee can make up a large proportion of the cost so difference between the two may not be that large!
I can't see that it particularly would. If the steam engine had already been lit up, then absolutely. Also things like paying staff to do fitness to runs, washouts and other maintenance, and marketing chaos. But otherwise, I don't think planning diesel in advance would be cheaper than changing to diesel last minute?
Diesels generally are cheaper to run but if steam engine already lit up could be marginal if steaming fee still has to be paid.
I think the Steam Railway article was suggesting that it costs more than coal. I think the VOR actually burn regular diesel in their oil burner!
If the locomotive is owned by an individual company or group (for example Southern Locomotives Limited) then there will often be hire aggreements whereby the railway operating the engine will pay a fixed fee per day the loco is lit up (I believe usually in the range £500-£1000 per day). Additionally, if one line hires their engine to another line, there will also be a steaming fee for that in some cases. For example, 6989 Wightwick Hall when it originally came to the Bluebell. Hope that helps.