[HN Gopher] Energy and Human Ambitions on a Finite Planet
___________________________________________________________________
Energy and Human Ambitions on a Finite Planet
Author : eleitl
Score : 51 points
Date : 2022-02-22 15:51 UTC (7 hours ago)
(HTM) web link (escholarship.org)
(TXT) w3m dump (escholarship.org)
| makerofspoons wrote:
| "Salvaging a decent future requires keen awareness, quantitative
| assessment, deliberate preventive action, and--above all--
| recognition that prevailing assumptions about human identity and
| destiny have been cruelly misshapen by the profoundly
| unsustainable trajectory of the last 150 years."
|
| 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.
| ben_w wrote:
| The way you're phrasing that gives me a certain impression of
| your beliefs about what is and isn't sustainable that may not
| be warranted, so I should ask explicitly:
|
| What do you think a sustainable way of life looks like? In
| terms of both global population size and typical life
| experiences.
| makerofspoons wrote:
| To me a sustainable lifestyle would be one where if every
| person alive today's annual consumption was at the same level
| humanity's demand for ecological resources and services could
| be regenerated over the course of that year- effectively
| balanced. I'm a fan of Earth Overshoot Day and their approach
| to this problem so I am using their definition:
| https://www.overshootday.org/about-earth-overshoot-day/. A
| sustainable way of life therefore looks like the average life
| of someone in Bangladesh, Sri Lanka, Nepal etc. I'm not
| holding up the average lives of people in these places as
| ideal (and I'm not considering anything other than
| consumption) but instead realistic about what level we can
| consume at with our current level of technology. Within that
| consumption envelope we need to figure out how to improve
| healthcare and education outcomes.
|
| 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.
| ben_w wrote:
| That's what I was expecting.
|
| Bad news, I'm afraid: If you keep the population _and_
| technology constant, the maximum sustainable consumption
| per person is lower than basic metabolic needs. Either the
| tech or the headcount needs to change, and nobody is going
| to let it be their head that gets dis-counted.
|
| The main reason for this isn't energy (current tech
| includes really cheap PV we just have not yet gotten around
| to building but could and likely will), it's phosphorus.
| Phosphorus is mined for use in fertilisers, it isn't
| renewed, the run-off flows into oceans.
|
| Only thing we know of that might help is more tech, and the
| tech _seems like_ it needs high-consumption societies to
| get proper funding.
|
| Naturally, if you can get good research going without that,
| that's a massive win for everyone, not just in this aspect.
| kiba wrote:
| It's already unsustainable enough that people are decrying
| how urban planning policies are destroying the tax base and
| social fabric of society.
| ben_w wrote:
| I think you've misunderstood the concern by several
| orders of magnitude here -- mere tax bases and so on are
| about as far from the fundamental functioning of the
| ecosystem as "living in a dumpster under a bridge" is
| from "needing to borrow the use of your neighbour's
| bathroom when you have a plumber in to fix your own".
| f0e4c2f7 wrote:
| Ctrl+f fusion.
|
| > "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.
| philipkglass wrote:
| _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._
|
| 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.
| adamsmith143 wrote:
| >The only heavy element that we actually "use up" to any
| significant degree is uranium
|
| Helium would like a word with you.
| philipkglass wrote:
| The only _heavy_ element. Helium is the second lightest of
| all elements. I didn 't think that the post I responded to
| meant helium because it said heavy elements (plural) and it
| referred to the far future, after mastering fusion as an
| energy source.
| deltaonefour wrote:
| It's still sort of a gamble.
| ttiurani wrote:
| > These pesky climate problems can be solved.
|
| 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.
|
| [1] https://en.m.wikipedia.org/wiki/Planetary_boundaries
| bsedlm wrote:
| disagree essentially because I believe we'd get into a
| situation where the problem becomes heat dissipation.
|
| the problem is the human psique, not technological
| capabilities.
| wilkommen wrote:
| I agree. I don't think humanity is happier given more
| resources, above a certain relatively small amount. But
| humanity's desires are limitless. If we are able to invent a
| free energy machine we'll just use it so much that it causes
| new problems.
| stouset wrote:
| If we find a cheap new way to generate orders of magnitude
| more energy, we'll _use_ orders of magnitude more energy.
|
| 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.
| saiya-jin wrote:
| You and parent project this in some theoretical universe
| where these effects would be ignored. Why on earth do you
| think so? With semi-unlimited energy at our palms, we can
| do serious geoengineering. We can put these furnaces into
| high orbits, or moon and beam down just raw output energy
| with lasers. Or whatever, even the sky isn't a proverbial
| limit.
| root_axis wrote:
| Fusion isn't magic, more energy doesn't suddenly obviate
| the burden of practical engineering constraints, we won't
| be "geoengineering" our way out of climate change for the
| foreseeable future.
| willis936 wrote:
| A world where energy consumption increases by a factor of
| 10,000 is a far fetched fantasy. If we're starting with
| such premises, should they not be followed?
| stouset wrote:
| A world where energy consumption increases by a factor of
| 10,000 would already be a world where the surface is lava
| thanks to basic thermodynamics. Earth can only radiate so
| much heat into space, and its ability to do so will not
| outpace energy production for much longer.
|
| A world where energy consumption increases fiftyfold is a
| century and a half away and would be brushing up against
| the point where we are noticeably increasing the
| equilibrium temperature of Earth _sans any greenhouse
| gases_. Hitting the thermodynamic limits of Earth 's
| ability to radiate heat into space isn't a far-fetched
| fantasy, it's _terrifyingly close_.
| willis936 wrote:
| This is very wrong. Humans produce about 30 TW of heat.
| The sun imparts 10 trillion times this amount. If we
| increased our production by 10,000 then we need to put a
| small umbrella in space to slightly dim the sun the
| smallest amount to maintain power balance.
| stouset wrote:
| Feel free to do the math yourself. You'll forgive me for
| trusting in the calculations of UCSD professor of physics
| Tom Murphy, who's written about this extensively.
|
| Edit: Also, your numbers are quite simply incorrect. The
| 70% of sunlight that doesn't bounce back into space is
| about 35,000TW, far from the trillions of terawatts you
| claim. At 2.3% energy growth for the next 275 years,
| we'll be adding 7,000TW to this number. That is _easily_
| enough to noticeably increase Earth's equilibrium
| temperature, and far less than this will be necessary to
| do so given greenhouse gases which reduce our ability to
| radiate heat into space.
|
| https://dothemath.ucsd.edu/2011/07/galactic-scale-energy/
| stouset wrote:
| Unlimited energy doesn't free us from the consequences of
| thermodynamics. Geoengineering doesn't help us. Where we
| generate the energy doesn't change anything if it's
| _used_ here on this planet.
|
| There are literal physical limits here that can't just be
| handwaved away by space magic. Higher energy use in a
| finite spherical volume _fundamentally_ results in
| increased temperatures when your only way of getting rid
| of that heat is radiation (and not convection or
| conduction). And we can 't just beam that heat away with
| space magic either thanks to entropy.
|
| Thermodynamics gives us _no tools_ to deal with this
| problem outside of increasing the spherical volume of
| Earth (and therefore its surface area).
| willis936 wrote:
| That is an overwhelmingly good problem to have. We would have
| truly mastered the planet for that to be a concern. As it
| stands, keeping society above water for the next hundred
| years seems like the grand challenge to accomplish. Do not
| assume victory is given. Nothing is a given. We are always on
| the edge.
| Retric wrote:
| This is filled with a lot of hand waving bad math, which
| distracts from some reasonable points.
|
| _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.
| zaphod4prez wrote:
| Sorry if I'm missing something, but... what's the problem with
| that quote? That's a widely-used heuristic that helps to
| estimate doubling times without using a calculator (see [the
| Wikipedia entry](https://en.m.wikipedia.org/wiki/Rule_of_72).
|
| 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.
| Retric wrote:
| The issue is he then uses the approximations to do with math
| without calling them approximations. 1.10^7 is reasonably
| close to 2, but 1.1^21 is 7.4 which is a fair distance from
| 8.
|
| 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.
| Loanor wrote:
| You do realize the rule of 70 is used to approximate
| continuous compounding not periodic compounding right?
| Retric wrote:
| There are a bunch of them though compounding normally
| uses the rule of 69 / 69.3, or rule 72.
| https://en.wikipedia.org/wiki/Rule_of_72
| Loanor wrote:
| The rule of 70 isn't "hand waving bad math".. perhaps you just
| don't understand its derivation?
| ZeroGravitas wrote:
| I feel like the author may have posted this to HN before, at
| least I remember a similar, book length take on this topic.
| fallingfrog wrote:
| Here's a fun little exercise: Open up a spreadsheet.
|
| 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)
| carapace wrote:
| I didn't have a spreadsheet handy: 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))
| reedjosh wrote:
| Because human economics in the realm of energy and or resource
| extraction are easily predicted by simple equations in a
| spreadsheet.
|
| So much so that this trivial exercise imparts real wisdom and
| is definitely not mental masturbation.
| fallingfrog wrote:
| Unfair - I didn't say that all human economics are easily
| predicted by a spreadsheet. It's an exercise. A starting
| point for discussion. As in: to start with, point out the
| assumption that is _wrong_. Rather than just insult me.
| reedjosh wrote:
| > Unfair
|
| Kinda I suppose. But the whole spreadsheet 'try this' trope
| is already unnecessarily hostile. You could put everything
| that spreadsheet exercise demonstrates into words.
|
| And that's my main argument too. This equation/exercise is
| so simple as to be useless.
|
| Human systems are multi-variate to the degree that a simple
| equation -- in this case showing that reliance on
| extractables is bad because their availability
| exponentially increases at the same time humans
| exponentially rely upon them more -- does not mean much of
| anything in the larger picture.
|
| This equation sidesteps human ingenuity, free market
| adjustments that will be made, predicted population decline
| in developed countries, and if the equation did apply,
| where on the timeline of the curve would we be.
|
| And those are just some of the criticisms of viewing the
| world through such a simple myopic lens.
| bckr wrote:
| I've got a lot of other homework... Could you provide a filled
| out worksheet or describe the behavior?
| notRacistSir wrote:
| pdonis wrote:
| The basic M.O. here is not new: (1) Present the basic math of
| exponential growth to show that exponential growth cannot
| continue indefinitely; (2) claim that sustaining our present
| lifestyle would require exponential growth to continue
| indefinitely; (3) conclude that our present lifestyle cannot be
| sustained.
|
| The issue, of course, is in step 2.
| arrosenberg wrote:
| Author even acknowledges it on page 27, but thinks _this time_
| Malthus must be right.
| chordalkeyboard wrote:
| what's the issue with step 2? Our present lifestyle _does seem_
| to require constant growth, and if this is not the case it
| would be nice for someone to explain how we can keep getting
| more out of the system without contributing more to the system.
| danbruc wrote:
| Why does our current lifestyle require constant growth, could
| we not just stop at our current energy consumption level?
| chordalkeyboard wrote:
| lots of reasons but population growth and our dependence on
| technology are two of the major ones.
| danbruc wrote:
| I was about to add ignoring population growth to my
| comment because developed countries are generally close
| to replacement-level fertility rate and I don't think
| having more children is part of or current lifestyle.
|
| Also lifting everyone to the living standard of highly
| developed countries will require significant amounts of
| resources and significantly increase energy consumption,
| this however is also more like a one-time expense and I
| would therefore ignore it, too.
|
| How does dependence on technology demand growth? Because
| resource extraction becomes less efficient as we deplete
| available sources?
| chordalkeyboard wrote:
| > I was about to add ignoring population growth to my
| comment because developed countries are generally close
| to replacement-level fertility rate and I don't think
| having more children is part of or current lifestyle.
|
| actually they are generally below replacement level,
| which (if not augmented by immigration) would itself lead
| to a collapse as people leave the workforce and there are
| fewer laborers to replace them. But people think we
| manage this labor shortage with technology, which leads
| us back to the requirements for more energy and capital
| development to maintain the same lifestyle.
|
| > Also lifting everyone to the living standard of highly
| developed countries will require significant amounts of
| resources and significantly increase energy consumption,
| this however is also more like a one-time expense and I
| would therefore ignore it, too.
|
| why do 'highly developed' countries need vastly greater
| resources to maintain this living standard if its a one-
| time expense? the greater standard of living your
| referring to requires continually expanding quantities of
| inputs in terms of energy and labor, aka 'economic
| growth'.
|
| > How does dependence on technology demand growth?
|
| its more related to the specific technologies we've
| chosen to build our society upon, but this technologies
| generally depend on these improvements to sustain
| themselves. For example, electric cars require batteries
| which require raw materials to be mined, recycling
| batteries requires chemical industry that is predicated
| on all sorts of inputs, themselves coming from
| nonrenewable sources.
| danbruc wrote:
| _actually they are generally below replacement level,
| which (if not augmented by immigration) would itself lead
| to a collapse as people leave the workforce and there are
| fewer laborers to replace them._
|
| Which is extra good as this offsets other parts of the
| world. I would also guess that it is probably easier to
| provide incentives for people to have more children once
| this becomes necessary than trying to prevent them from
| having too many children, but that is not much more than
| a gut feeling.
|
| _But people think we manage this labor shortage with
| technology, which leads us back to the requirements for
| more energy and capital development to maintain the same
| lifestyle._
|
| If we permanently fall below replacement-level fertility,
| we will just die out and no amount of investment will fix
| this. The only solution is to match replacement-level
| fertility which will provide a stable population and
| workforce and hence require a stable amount of economic
| activity to achieve a stable lifestyle. The obvious
| caveat is of course that the economic activity must not
| deplete any non-renewable resources.
|
| _why do 'highly developed' countries need vastly greater
| resources to maintain this living standard if its a one-
| time expense? the greater standard of living your
| referring to requires continually expanding quantities of
| inputs in terms of energy and labor, aka 'economic
| growth'._
|
| The one-time expense is to lift someone from say 2,000
| kWh/a to 40,000 kWh/a which requires adding the
| difference in production capacity. After that this person
| will of course consume 40,000 kWh every year and we will
| have to produce those 40,000 kWh every year, but I don't
| think that constitutes economic growth. Economic output
| is quantified as absolute output over some period of
| time, not as cumulative absolute output.
|
| _For example, electric cars require batteries which
| require raw materials to be mined, recycling batteries
| requires chemical industry that is predicated on all
| sorts of inputs, themselves coming from nonrenewable
| sources._
|
| I still don't see how this requires continued growth if
| we assume constant output.
| pdonis wrote:
| _> Our present lifestyle does seem to require constant
| growth_
|
| 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.)
| chordalkeyboard wrote:
| > 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.
|
| world population is leveling off because we're approaching
| many of these limits to growth and that's affecting the
| enabling factors for continued population growth.
|
| > 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.
|
| I agree with this.
|
| > "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.
|
| you conflate value and price here. obviously atmosphere is
| not currently metered. That doesn't mean we don't place a
| high value on clean air.
|
| > And if the cost of production of other life-essential
| resources, like food, were reduced, those things would also
| become cheaper.
|
| https://en.wikipedia.org/wiki/Jevons_paradox
| pdonis wrote:
| _> you conflate value and price here_
|
| I'm not doing that. I'm pointing out that the author of
| this paper is doing that. He is assuming that everything
| of value is captured in the GDP, i.e., in money spent.
| But as you acknowledge, this is false, and that
| invalidates his argument.
|
| _> https://en.wikipedia.org/wiki/Jevons_paradox_
|
| The Jevons paradox does not say things don't become
| cheaper when their cost of production is reduced. So it
| is not an argument against the statement of mine that you
| were responding to here.
|
| Also, if we are talking about life-essential resources
| like food (or air), which was what I was talking about in
| the comment you responded to here, the Jevons paradox is
| of limited applicability if it applies at all, because
| demand for such resources is constrained. Even if food
| were free, people would not eat an unlimited amount of
| it, any more than they now breathe an unlimited amount of
| air because air is free. The most important factor
| driving an increase in total consumption of such
| resources is population increase, so if population levels
| off, the resources consumed for these life-essential
| things will be naturally limited no matter how cheap they
| become.
| adamsmith143 wrote:
| https://en.wikipedia.org/wiki/The_Limits_to_Growth
|
| Figured this out decades ago.
| [deleted]
| 1053r wrote:
| The entire book falls apart because of two facts, both of which
| are in the book itself!
|
| "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.
| justbrowsingthx wrote:
| I'm not sure I understand your point. Perhaps you disagree with
| the author on the desirability of a future in which virtually
| unlimited energy is available to humankind in its current state
| (see the upshot on nuclear fusion p. 269, for example). His
| cautious take on our collective ability to manage our energetic
| needs[0] does not seem unwarranted to me.
|
| 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)
| stouset wrote:
| "Virtually unlimited energy" is where the argument completely
| falls apart. It's a myth we need to stop spreading. As I said
| elsewhere, we have only a bit over 200 years at our current
| 2.3% annual growth in energy usage before we start raising
| the temperature of the Earth purely from a thermodynamic
| perspective.
|
| 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.
|
| https://dothemath.ucsd.edu/2011/07/galactic-scale-energy/
| ben_w wrote:
| > 18.4 Fermi Paradox Explained?
|
| 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.
| westcort wrote:
| I like the last chapter, which shows some strategies for reducing
| energy use.
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