I assume that it makes sense to ask for the energy costs of transportation of different goods per weight and volumetric mass density, depending on the means of transportation (truck, train, ship, etc.) and on the distance of transportation.
I assume that there are either data or plots for this, but I don't know where to find them. A typical plot I'm looking for would answer the question:
How much energy (including losses) does it take to transport one metric ton of good X (having volumetric mass density $d$) by train for 100 resp. 1000 miles, today and 100 years ago?
In case you don't find this question (or approach) sensible, please tell me why.
Background: I'm planning a data visualization project of transportation of all kinds of goods. One part of the project will be the routes of transportation: along which paths and for what distances are which volumes of goods transported? (On a global and a local level.) Another part shall be the costs of transportation (to which finally will also count the costs of lifting goods, e.g. in a harbour, but maybe these are negligible).