[willyt]

According to the back of my jar of mayonnaise there is 8400kJ stored in it, enough energy to power this rpi for ~62 days. This is probably a stupid question but just out of curiosity, why do people express electrical energy in Watts per second or Watts per hour instead of Joules. Unless school physics has deserted me completely 1 Ws = 1J no?

[omikun]

Because no one talks about units of Ws. It's all Wh or kWh. Or they talk about power instead of energy.

[willyt]

Well you didn't read the article because the comparisons of the energy consumed are listed in Ws (Watt Seconds)

e.g.

> We can now boot into a Linux user space program in less than 3.5s!

>~400ms is spent in the Linux kernel (difference between pin 0 and pin 1)

>Total energy consumption: 0.364 As * 5.0 V = 1.82 Ws