Energy and Human Ambitions on a Finite Planet, 2021a

2 Economic Growth Limits 22
theoretical maximum
luminous efficacy (lm/W)
10 2
10 1
10 0
c<strong>and</strong>le
gas lamp
LED
fluorescent
halogen
inc<strong>and</strong>escent
10 -1
1200 1300 1400 1500 1600 1700 1800 1900 2000 2100
year
Figure 2.3: Historical progress of lighting
efficiency on a logarithmic plot, using bars
to indicate the approximate range of time
<strong>and</strong> performance. The dashed line at top
represents the maximum theoretical luminous
efficacy for white light (no waste heat).
The dotted line rises by our customary factor
of ten per century (2.3% annual rate).
Note that the guiding line reaches the theoretical
maximum mid-century (red star),
indicating that this centuries-long ride cannot
continue much longer [10, 11].
The historical progress can fool us into thinking that we can expect a
continued march to better substitutes. Having witnessed a half-dozen
rabbits come out of the hat 12 in the example of lighting technology (Box
2.1), we are conditioned to believe more are forthcoming. It will be true
until it isn’t any more (e.g., see Figure 2.3) One way to put it is that 6
rabbits does not imply an infinite number. We should welcome each new
rabbit, but not hinge our future on a continual stream of new rabbits.
For financially secure individuals at the top end of the wealth distribution,
it is easier to buy into the allure of substitution as a way forward. Many
have achieved wealth from humble beginnings, <strong>and</strong> have therefore
lived a life of continual upgrades in terms of housing, transportation,
clothing, food, travel, etc. Even those who have been surrounded by
wealth their whole lives have been in a position to afford new upgrades
as they become available. Yet, it is not always possible to export the
capabilities of those at the top to a significant sector of the population.
Not everything can scale.
Box 2.2: The Fate of the Concorde
The fate of the Concorde—which offered supersonic transatlantic
passenger service between 1976–2003—may offer a useful lesson
here: just because it is possible to construct a supersonic passenger
airplane does not mean that enough people can afford it to result
in an economically viable reduction in trans-oceanic travel time for
all. Consumers no longer have the option for supersonic flight,
even though 50 years ago it was assumed that this was the future.
Sometimes we go backwards, when our dreams don’t line up to
practical reality.
12: . . . magician reference
We will return to this theme in the context
of fossil fuels, which might be termed the
mother of all rabbits, in this context. Having
pulled such a stupendous rabbit out of the
hat once, many assume we’re set from now
on. In this case, equating one to infinity is
even more dubious.
An electric car having hundreds of kilometers
of range seems like an obvious path
forward beyond fossil fuels. But at a price
tag above $40,000, it does not look like much
of a solution to most people, <strong>and</strong> we can’t
be sure prices will fall steeply. Section D.3
covers electrified transportation in more
detail.
More generally, sometimes the best possible solution <strong>and</strong> “peak” technology
arrives at some early point in history. As much as we mess around
with elements on the Periodic Table, we are never going to beat H 2 O
© 2021 T. W. Murphy, Jr.; Creative Commons Attribution-NonCommercial 4.0 International Lic.;
Freely available at: https://escholarship.org/uc/energy_ambitions.