At the same time what was brewing was a widespread opposition to overhead conductors for streetcars. Even Sprague had initially believed that few large cities in the United States would permit overhead system and that this system was simply out of question in cities where opposition to overhead wires had already developed.

Because of this public objection to overhead wires, underground-conduit system remained popular among inventors, accounting for a large percentage of electric streetcar patents well into the 1890s. There was also plenty of technical evidence that underground-conduit systems would be feasible, although they would be considerable more expensive than overhead systems because of the need to excavate the street for the conduit. In 1890 the city of Budapest opened the first successful conduit system in Europe. The system proved to be profitable, and American inventors soon developed similar systems. The opponents of the trolley system frequently pointed to the Budapest system as a viable system.