"Hands down, solar is the only renewable resource capable of matching our current societal energy demand. Not only can it reach 18 TW, it can exceed the mark by orders of magnitude." (Section 13.9)
"We would likely not be discussing a finite planet or limits to growth or climate change if only one million humans inhabited the planet, even living at United States standards. We would perceive no meaningful limit to natural resources and ecosystem services." (Section 3.5) An energy source that is thousands of times more abundant than fossil fuels is basically equivalent to having one one thousandth the population.
While I must acknowledge the truth that converting things to run on electricity will be a large engineering and logistical challenge, and that battery production must be scaled up (as well as converting some loads to run where the sun is shining), both of these challenges pale in comparison to the money part of that first quote: "exceed the mark by orders of magnitude." In other words, even if we could only store electricity at an efficiency of 1%, we'd be fine. (In actuality, we ALREADY store electricity at efficiencies over 80 times that.)
Ecosystem services, availability of raw materials, and many other challenges exist as well. However, all of them are meaningless in the face of "we would perceive no meaningful limit to natural resources." Having an energy source that is thousands to millions of times more abundant than the ones we use today lets us substitute energy for basically all of our needs. (Need clean water? Energy + dirty water = clean water. Need more steel? Dirt + energy = steel. Need to remove CO2 from the atmosphere? You can do it, at only the cost of several times the energy you got putting the CO2 into the atmosphere, which is only a few % of the future energy budget from solar. Think of it this way. In the past, we relied on cutting down forests for heat. Putting the forests back would have seemed like an insurmountable task, because our fuel came from the forests. But now that we run on fossil fuels, which are approximately 100x more abundant than forests, putting the forests back is a matter of politics and land usage discussions, not one of practicality.)
In other words, we are the only ones we have to blame if the future is not MUCH wealthier than the past, both per person and also for our total economy.
Regardless, I think the book remains useful for its intended audiences as a quantitative assessment of available energy sources given our growth path.
[0] "The rookie mistake here is assuming that adults are in charge." (p. 134)
Completely blanketing the Earth in solar panels gets us a few hundred years more (thanks to the fact that that solar energy is already hitting the planet whether or not we use it for electricity), but that's assuming we've developed panels with magical levels of efficiency and we're okay with 0% of sunlight reaching the Earth's surface.
Four hundred years of sustained energy growth at current levels is the most that could happen on this planet under comically-implausible circumstances, and when we reduce the absurdity even just a bit (greenhouse gases still exist, we won't blanket the planet in perfectly-efficient solar cells), we optimistically might get two hundred years more before we hit an energy wall that cannot be overcome without a complete overthrow of thermodynamics as we understand it.
Is that still a lot of growth? Sure. But it's about the same window of time as the industrial revolution until now.
> "Fusion is therefore a complicated and not particularly cheap way to generate electricity. Meanwhile, we are not running terribly short on renewable ways to produce electricity: solar; wind; hydroelectric; geother- mal; tidal."
Fusion is the key to long term success for humanity. It paves the way to essentially unlimited cheap burstable power.
In the even longer term plasma fusion offers a way to create the heavier elements that we are running out of here on earth. Forged in a manmade nuclear furnace.
These pesky climate problems can be solved. We just have to mine ideas out of nature now instead of minerals.
If you're trying to think about humanity's long term prospects fusion should be the crown jewel, not an after thought you handwave away. I believe today we spend somewhere on the order of 1% of what we should be spending on fusion research.
The only heavy element that we actually "use up" to any significant degree is uranium, which is consumed for energy, but if we had cheap fusion energy uranium consumption would plummet. Even if we could make artificial uranium it would be a net-energy-losing process to make artificial uranium with fusion power instead of using fusion power directly.
Helium would like a word with you.
The thing is, it's not just climate that's the problem. The "pesky" problem is that we've crossed or are soon crossing most planetary boundaries[1] at the same time.
Fusion doesn't stop and reverse biodiversity loss, chemical pollutants, land-system change, biochemical flows, ocean plastic buildup and ocean acidification.
To stop the ecological collapse, the necessary condition is that the global North drastically reduces material flows and energy consumption. With less energy use, fusion also becomes less critical.
the problem is the human psique, not technological capabilities.
And you're right. We're only a bit over two hundred years away at 2.3% annualized growth in energy use from noticeably raising Earth's surface temperatures just from a thermodynamic perspective. And that's completely ignoring the effects of greenhouse gases.
Brilliantly said. I believe a lot of resistance to the idea that our way of life is unsustainable stem from grief that the future that we were "promised" by the last century of media and marketing isn't coming. The first step towards adapting to the imminent collapse of the high-consumption lifestyle due to energy and resource limitations is to process this grief.
What do you think a sustainable way of life looks like? In terms of both global population size and typical life experiences.
That's why I expect we're headed for tragedy- we can't and won't collapse everyone's consumption to that level. The people who consume the least will be the most hurt by the ecological consequences of what we in the high-consumption regions of the world do.
Label the first column C for capital. This starts at 1.
Label the second column T for total resources extracted. This starts at 0.
Label the third column r for resources extracted this step.
Label the fourth column E for extraction efficiency.
Label the 5th column m for maintenance. Make it proportional to capital.
Now, for each step:
E is some positive function of T with a negative slope. It doesn't have to have a finite area under the curve (you don't have to assume total resources to be finite, in other words). You just have to assume that the next unit of resources to be extracted requires a bit more effort than the last one. Use E = .1*exp(-.01*T) or something like that.
r = C*E
m = C*k where k is any positive number between 1 and 0- .01 is a good constant to use.
C += r*q - m where q is again some constant, say .2
T += r
Now observe the behavior of the system. Plot the value of C over time. For the above constants you'll want to include about 3000 steps.
(Edit: forgot the maintenance term)
from math import exp
k = .01
q = .2
C = 1
T = 0
E = lambda T: 0.1 * exp(-0.01 * T)
for step in range(3000):
r = C * E(T)
m = C * k
C += r * q - m
T += r
print('%5i %g' % (step, C))So much so that this trivial exercise imparts real wisdom and is definitely not mental masturbation.
The issue, of course, is in step 2.
Figured this out decades ago.
No, it doesn't. The obvious cause of the huge economic growth over the past 150 years, which is what the author focuses on, is population growth. World population is expected to level off in this century.
The author also assumes, incorrectly, that GDP--money spent on goods and services--is the right measure of overall wealth. It's not. The author even discusses "decoupling", the fact that many types of wealth require little or no physical resources to produce, but fails to realize that the long term outcome of this will not be to raise monetary GDP more and more, but to make monetary GDP less and less of an accurate measure of wealth production.
Finally, the author misunderstands basic economics when he says (p. 25): "A limited life-essential resource will always carry a moderately high value." This is a common misconception. An obvious counterexample is air: air is a limited resource (Earth's atmosphere contains only a finite quantity of it), it is life-essential, but it is free. Why? Because it costs nothing to produce. And if the cost of production of other life-essential resources, like food, were reduced, those things would also become cheaper. (In fact, that has already happened to a large extent in the developed world: over the past 150 years, the fraction of people involved in food production has dropped from about 19 in 20 to about 1 in 20. The main reason food is not much cheaper as a result of this is political: governments artificially manipulate the markets for food, for example by paying farmers not to grow certain crops. This is fixable without any increase at all in our expenditure of physical resources.)
rule of 70tells us that the time it will take a system or collection to double in size is 70 divided by thepercentage growth rate. The time units depend on how the time over which percentage growthis expressed—like 2%per dayor 2%per year, for instance. The rule works most accurately forsmaller growth rates, under 10%.
Actually showing 1.10^7 = 1.949 vs 1.01^70 = 2.007, so you can approximate by dividing percentage by 70 between 1% and 10% is fine. Stating it as true in the text then adding a note well no not actually latter on is problematic.
He does walk the reader through a lot of “back of the napkin” math, in order to help the reader get an intuitive sense of the models he’s using. But my impression overall is that he backs those hand-wavey calculations up with more serious calculations throughout the book.
He goes so far as asks someone to do the approximation across several hundred years of compounding. And sure it get’s a big number but one no even close to accurate.
I’m currently leaning in this direction myself. Not necessarily just this, but “big filter ahead” (or lots of small filters). Perhaps it will be this, perhaps it will be a Jonestown massacre but with entire O’Neill cylinders instead of individual people, leading to a Kardashev II scale Kessler syndrome.