While reading the other day, I discovered that voltage drop and real power losses contributed to the invention of the incandescent lightbulb. In the late 1870s, most research on suitable light-bulb filament revolved around low-resistance materials. Thomas Edison, instead, focused on high-resistance materials for the filament, reasoning that constructing an economic power system would require small-diameter conductors (because they were much less expensive than large-diameter conductors). Edison knew that if a system was going to be built with small conductors, however, it would require low-load currents so that excessive voltage drop and power losses would not be introduced. To get low currents, he knew that the lightbulb - one of the killer apps of the electric world at that time - would have to have a high-resistance filament. This led to Edison's eventual discovery of the carbonized cotton-thread filament - and subsequently the carbonized cardboard filament - that evolved into the commercially viable incandescent light that changed the world.
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