The purest enjoyment of life - be a RailFan.

Yes.
But a nostalgic value is associated with these bulbs seen in the train compartment in old days.
Another important point is there to replace bulbs with tubes on the part of Indian Railways.
A tube can consume much less power than a bulb.
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CFL(Compact Fluorescent Lamp) consumes much less power than both bulb and tube. Please see the following:
Compact Fluorescent Lamp are the energy saving lamps, designed to reduce the power consumption by old incandescent lamp. Modern CFLs typically last at least six times more than an equivalent incandescent bulb and consumes only 25% of the power. But, they generally cost slightly more than incandescent bulbs.CFLs are 2 types :
Integrated - Integrated lamps combine the tube and ballast in a single unit. They are designed to provide the compatibility in replacing the old incandescent lamp.
Non-integrated - Non-integrated CFLs have the ballast permanently installed in the luminaire, and only the lamp bulb is usually changed at its end of life. They less flexible as compared to its Integrated counterpart.
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In general 2 nd class compartments CFL are also used today.
In AC three tiers of Garib Rath, SDAH Puri Duronto, CFLs are used for illuminating the compartment.
Attached Image:
CFL Lamp
Source: click here
Thanks