Cheaper railway electrification
Posted: 21 Oct 2007, 16:19
Electric railways have many advantages including no pollution at the point of use, and the ability to use electricity from any source, including renewables.
The principle drawbacks are the very substantial capital costs, and the vulnerability to any interuption in the power supply.
I believe that these disadvantages may be overcome by using a new design of electric locomotive or electric multiple units. These should incorporate a battery with sufficient capacity to move the train at reduced speed for perhaps ten miles.
The use of such trains should result in very dramatic savings on the cost of infrastructure.
The vast cost of railway electrification is not primarily due to the cost of overhead wires, supports, transformers etc. The real money is spent on lowering the track in tunnels, raising the height of bridges, and altering staions, in order to provide the required clearances between the 25,000 volt wires and anything else.
Many bridges, tunnels and other structures are listed, which adds even more expense.
Use of battery assisted trains would avoid the need for any of this expensive and very disruptive work. Wherever clearences are insufficient, the over head wiring would be terminated each side of the limited clearence section, and the train would proceed on battery power.
(in order to reduce wear on the battery, drivers would be instructed to coast through dead sections whenever possible.)
In the event of a power failure, a battery assisted train should be able to continue to the next station, from whence passengers may be conveyed by other means, clearly better than being stuck miles from anywhere, or in a tunnel.
If the train can not proceed due to an accident or breakdown ahead, then the battery could supply internal lighting and ventilation for many hours.
The train could also be moved at low speed on battery power in the depot for cleaning, filling of water tanks etc. This would improve safety and simplify/cheapen the equiping of the depot.
There could also be energy savings by using regenerative braking to charge the battery, this would avoid the hazards of trying to return surplus power to the overhead line.
Battery power has been considered in the past and has been rejected due to the cost, weight and bulk of the battery. Recent advances in batteries (largely driven by the development of hybrid road vehicles) should make the idea more practical than in the past.
Note that the above is not my own work, I qoute it , with permision from a railway engineer whom I met recently. I do however agree that the idea is worth pursuing.
The principle drawbacks are the very substantial capital costs, and the vulnerability to any interuption in the power supply.
I believe that these disadvantages may be overcome by using a new design of electric locomotive or electric multiple units. These should incorporate a battery with sufficient capacity to move the train at reduced speed for perhaps ten miles.
The use of such trains should result in very dramatic savings on the cost of infrastructure.
The vast cost of railway electrification is not primarily due to the cost of overhead wires, supports, transformers etc. The real money is spent on lowering the track in tunnels, raising the height of bridges, and altering staions, in order to provide the required clearances between the 25,000 volt wires and anything else.
Many bridges, tunnels and other structures are listed, which adds even more expense.
Use of battery assisted trains would avoid the need for any of this expensive and very disruptive work. Wherever clearences are insufficient, the over head wiring would be terminated each side of the limited clearence section, and the train would proceed on battery power.
(in order to reduce wear on the battery, drivers would be instructed to coast through dead sections whenever possible.)
In the event of a power failure, a battery assisted train should be able to continue to the next station, from whence passengers may be conveyed by other means, clearly better than being stuck miles from anywhere, or in a tunnel.
If the train can not proceed due to an accident or breakdown ahead, then the battery could supply internal lighting and ventilation for many hours.
The train could also be moved at low speed on battery power in the depot for cleaning, filling of water tanks etc. This would improve safety and simplify/cheapen the equiping of the depot.
There could also be energy savings by using regenerative braking to charge the battery, this would avoid the hazards of trying to return surplus power to the overhead line.
Battery power has been considered in the past and has been rejected due to the cost, weight and bulk of the battery. Recent advances in batteries (largely driven by the development of hybrid road vehicles) should make the idea more practical than in the past.
Note that the above is not my own work, I qoute it , with permision from a railway engineer whom I met recently. I do however agree that the idea is worth pursuing.