Instead of RoLa :D.

Title of idea (in 2010, maybe i rewrite this...)

2.) A new, more efficient way of intermodal(railway/highway) transportation.

Exploit the benefits of both railway and highway transportation and minimize their drawbacks by optimally mixing the two methods.

Railway transportation between two points is cheaper and more environmentally friendly, than highway transport, however the later has the advantage of higher flexibility.

Below we describe the case of single delivery of goods between two locations, however the method can be generalized to multi point delivery as well.

Suppose that a company having only a single tractor has to deliver N trucks of goods, to a location (B) that is M km away from the starting point (A) on road and after that the tractor has to return to A. Suppose also that the combined distances of nearest railway stations from points A and B is R., while the distance between these stations over the railway is L, and the cost of transporting a truck 1 km on road is F_road, and on railway is F_rail. See explanatory figure 1. It is widely accepted that F_rail <F_road.

If the company would transport the trucks over highway it would mean N turns and 2NMF_road cost.

Alternatively if a railway service would exist which would involve special long carriages that could fit in a truck, than the company could subscribe to this service and the tractor may deliver the trucks one after another to the nearest railway station at A’, load the railway carriages one by one, and then the tractor is put on the train as well (together with the last truck). Once the train arrives to the station nearest to B than the tractor again delivers the N trucks one by one to point B. In this case there will be N-1 turns both at A and at B, thus altogether 2N, and the overall cost is (2N-1)RF_road+LNF_rail+MF_road. As can be seen the mixed way of transportation is less costly if

(2N-1)RF_road+LNF_rail+MF_road) < 2NMF_road, or

(2N-1)RF_road+LNF_rail<(2N-1)MF_road,

R<M-LNF_rail/(2N-1)F_road.

To get a weaker but simpler condition we can assume that N>>1, and if F_rail is overestimated by assuming it to be the same as F_road, then the mixed transportation will be more cost efficient if

R<M-L/2.

The above condition can be easily probed e.g. over electronic maps of the internet for any specific A and B location of interest.

For this service to work buffer areas have to be developed at the railway stations where the trucks could be accumulated until the loading of the train. Also the special railway carriages needs to be developed (see schematic figure 1 below), where the tractor can load the truck on the carriage (with reverse motion from the side of the carriage), and which would have means to be locked e.g with a code key (the service provider would supply the code) . Finally some IT background needs to be in place for the booking of the buffer area, obtaining accurate time table information and for the ordering of the service, (the same conditions that are at place for the already existing types of intermodal transportation).

The above described case of point to point delivery can be extended to multi point scenario as well, similar to the distribution of goods of large supermarket chains from a central warehouse.

The main difference between the described idea and the already existing types of intermodal transportation like RoLa (http://en.wikipedia.org/wiki/Rolling_highway) is that in our case only a single tractor is involved in the transportation. Instead of the high dead weight of many tractors on the train it involves only a single tractor for many trucks, and also the loading of carriages is more simple than in the case of RoLa, and in length the two methods are comparable.

The above described way of transportation could be beneficial for logistics companies, (even small ones), and also for railway companies, because of the profit coming from this service. Apart from the commercial advantage of the involved parties, general public would also benefit by the smaller environmental impact and smaller load on the highways.