What fuel did the first motor buses use?

The first motor buses used petrol. Karl Benz built the earliest recognized motor buses in Germany in 1895 for the Netphener bus company, using internal-combustion petrol engines rather than steam, batteries, or diesel.

Petrol-powered buses emerged during a period when several technologies competed with horse-drawn transport. Steam buses had appeared earlier, but their boilers were heavy, slow to start, and difficult to operate. Battery-electric vehicles also existed, yet limited range and battery weight made them impractical for early bus services.

Petrol engines offered a better combination of relatively low weight, quick starting, and usable range. In Britain, early services included Daimler petrol buses in London from 1899, followed by larger petrol-powered fleets in the early twentieth century.

Diesel eventually became dominant for many heavy buses because it delivered better fuel economy and pulling power, but it was not the fuel of the first motor buses. “Motor bus” here means an engine-powered road bus, not a trolleybus drawing electricity from overhead wires.