Caption: James Joule (1818-1889) was a 19th century scientist in the field of thermodynamics---and he was also a brewer---you can have a Joule's. He is the eponym of the metric system energy unit the joule (J).
For more on James Joule (1818-1889), see Physics file: james_joule.html.
One of the curses of discussions about energy and power in society is the use of inconsistent and meaningless units.
A few useful conversions with remarks:
- 1 megaton of TNT equivalent = 4.184*10**15 J = 1.162*10**9 kWh = 132.6 megawatts for 1 Julian year = (0.04656 kg)*c**2 = (46.56 g)*c**2.
- 1 MToe = 10**6 tonnes of oil equivalent = 41.868 pJ---another unit to die for.
- 1 terawatt-hour (TWh) = 10**9 kiloawatt-hours (KWh) = 3.6*10**15 joules (J).
- 1 terawatt-hour/year (THh/yr) = 1.140771161 ... )*10**(-4) terawatts (TW) ≅ 10**(-4) TW: The terawatt-hour/year has to be one of the most useless units ever invented: meaningless compared to anything else. But Our World in Data thinks it OK. See Our World in Data: Primary energy consumption by world region (2024) where worldwide commercial power usage is of order 18 TW after some eye-ball addition and conversion. Wikipedia: World energy supply and consumption: Primary energy production (2021) gives 19.6 TW after a lot numbers in MToe = 10**6 tonnes of oil equivalent = 41.868 pJ.
Credit/Permission:
Henry Roscoe (1833--1915)
from
Sir Henry Enfield Roscoe,
The Life & Experiences of Sir Henry Enfield Roscoe, 1906, Macmillan: London and New York,
p. 120 plate
(uploaded to Wikipedia
by User:Astrochemist,
2007) /
Public domain.
Image link: Wikipedia:
File:Joule James sitting.jpg.
Local file: local link: energy_units.html.
File: Physics file:
energy_units.html.
