Václav Smil wrote

A new round of industrial revolutions has always coincided with the discovery of new types of energy. And the most important inventions in energy are not those devices or phenomena that produce energy, but those that transform one type of energy into another - with less loss than before. The clearest example is Watt's invention of the steam engine. It allowed people to produce energy independently of any natural source nearby, such as a river. This accelerated the processes of urbanization and industrial development in cities. This principle is used even today: if you don't know, even nuclear power plants are just large pots of boiling liquid.

As a result of a half-century-long race for efficiency, frugality, and storage capacity, the world has come to the point where energy conservation has become more profitable than producing additional gigawatts. Every dollar invested in producing high-efficiency equipment creates 8 times as many jobs as a dollar invested in energy generation. It's not how much oil you pump out that matters, but how many miles you drive by refining it. And since 1975, the distance the average car can travel on a liter of gasoline has doubled. Huge SUVs now have the same consumption per hundred as a C-Class sedan did 30 years ago.