Thermodynamics of prime movers: energy from first principles? - Highlighted Article

From: Thunder Said Energy

Date: December 12, 2023

Thermodynamics of prime movers: energy from first principles?

A highlight of 2023 has been going back to first principles, to study the underpinnings of prime movers in the global energy system. Context matters. There is no energy source to rule them all. However, if you understand the thermodynamics of prime movers, you will inevitably conclude that the world is evolving towards solar, semi-conductors, electro-magnetic motors, lithium batteries and high-grade gas turbines.

Muscle power was the original prime mover in the pre-industrial energy system (chart below). But a typical horse outputs 0.75 kW of power, converts only c10-30% of food energy to useful work (depending on how hard you work the horse), can only cover 25-40 miles in a day, must be treated humanely and annoyingly poops everywhere. So we would score horses as a 1 out of 6 on our score of prime movers. It is remarkable that despite these limitations, the total global population of horses remains flat on 1960, with around 60 million horses in the world today, showing how hard it is to disrupt established technologies. (continue reading)

Thermodynamics of prime movers: energy from first principles?