Energy and Human Ambitions on a Finite Planet, 2021a

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barrel
(bbl) is a unit of volume used primarily for petroleum. It is exactly 42 U.S. gallons, amounting
to 159 L of volume. A commonly used measure of energy is barrels of oil equivalent (b.o.e.),
amounting to 6.1 GJ of combustion energy. 112, 119, 126, 129–131, 135, 141, 211, 266
beta decay
(β) happens when a nucleus emits either an electron (β − )orapositron (β + ). 243, 245, 265, 435,
438
Betz limit
is a theoretical maximum amount of kinetic power that can be removed from wind without
slowing the wind too much. It computes to 19/27, or 59%, <strong>and</strong> is independent of technology [71,
72]. 188, 189, 195
Big Bang
is the name given to the start of the universe, about 13.8 billion years in the past. 9, 55, 239, 257,
392, 394, 396
biofuel
describes a liquid chemical fuel derived from biologically grown plants: algae, sugar, corn,
rapeseed, etc. The two most common forms are ethanol <strong>and</strong> biodiesel. 165, 227, 230, 231, 428
biomass
is a generic term for biological matter, but in the energy context usually means firewood or
dung that may be burned for thermal energy. 170, 227, 229–231
birth rate
quantifies the number of births per 1,000 people per year, typically. Numbers tend to be in the
5–30 range. 38, 426
blackbody
is a term describing the radiative qualities for thermal emission of light (infrared radiation
for “normal” temperatures, becoming visible for very hot objects). A perfect blackbody is
not reflective (i.e., “black” at the wavelengths of interest) <strong>and</strong> emits energy as a function of
wavelength according to the Planck spectrum. 145, 199–201, 203, 223, 434, 438
boiling water reactor
is a type of nuclear fission reactor in which water surrounding the fuel rods acts both as a
moderator <strong>and</strong> as the means of transporting heat away from the nuclear fuel. 255, 256
Boltzmann constant
is a fundamental constant of nature associated with thermodynamics. In SI units, it has a value
of k B 1.38 × 10 −23 J/K. 89, 199, 381
breeder reactor
is a nuclear fission reactor that transforms non-fissile nuclei into ones that are fissile by means
of neutron capture <strong>and</strong> subsequent radioactive decay. 250, 262, 264, 296, 423
breeding
see breeder reactor. 259
British thermal unit
(Btu) is a unit of energy in the Imperial unit system, defined as the amount of energy required
to heat one pound of water by 1 ◦ F. It is equivalent to 1,055 Joules. 75, 423, 427, 435, 437
Btu
is short for British thermal unit. 75, 97, 98, 335, 372, 423
Calorie
(Cal, or kcal) is a unit of energy, defined as the amount of energy required to heat one kilogram
(1 kg, 1 L, 1,000 cm 3 ) of water by 1 ◦ C. It is equivalent to 4,184 Joules, <strong>and</strong> is the exact same
© 2021 T. W. Murphy, Jr.; Creative Commons Attribution-NonCommercial 4.0 International Lic.; Freely available at:
https://escholarship.org/uc/energy_ambitions.