>>12156571The first electric motors were built in 1740s but only became practical for work in 1832.
The first photovoltaics were developed back in 1839, but only thanks to space money in the 60s they became viable technology to get energy.
The idea of Fusion Reactors was developped in 1946, in the 90s we made the first viable fusion reactions. We are expecting net-gain fusion reactions by the 30s, the timescale is nothing to sneer at.
