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Tidal energy is not renewable

cs.stanford.edu

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Re: Tidal energy is not renewable

#171

Post by iamthemonster »

I really love this kind of thinking and explanation - it may not be correct per se, but it's the TYPE of thinking we need.

Rather than fluffy repetitions of the slogans of in-groups, it's an attempt to explore long term impacts using fundamental scientific principles, none of which are individually too complex.

And if we don't agree with the 2% annual energy growth rate for 1000 years then that's fine, we can fiddle the numbers for what we believe, and the same analysis can be valuable even if it ends up supporting a different conclusion.

I'm interested by the language style as well, it reads like they put it through a filter to generate "simple English" as a deliberate choice.

Re: Tidal energy is not renewable

#172

Post by ben_w »

mattmaroon wrote: post #157
ben_w wrote: post #155

Earlier quoted context omitted.

> I can’t even imagine what I could do on Earth using that much power. Fly my own 737 to a new city every day? Sure, why not? It's absurd today for the average person, but it's the kind of thing rich people get to do already, and looking at the rich today is a decent (though imperfect because inflation and invention don't work like that) hint for what normal people can afford in a richer future.

Aviation historically, has not gotten cheaper overtime. If anything, it is more expensive. Only rich people had planes 100 years ago and only rich people own them now and the trend line doesn’t indicate it’ll be different in another hundred.

Nobody owned a 747 a hundred years ago.

Cheapest flight I've ever taken was 9.99 from Berlin to London — not sure if pounds or euros, but does it matter when either way it is less than I used to spend on a week of school lunches nearly 20 years earlier?

Re: Tidal energy is not renewable

#173

Post by hgsgm »

wmf wrote: post #149
littlestymaar wrote: post #101

Earlier quoted context omitted.

> Look at the US energy consumed per capita, flat or declining for the last 50 years. This doesn't account for all the “imported energy” that comes when you outsource your industrial production abroad. Granted even then the energy consumption doesn't increase exponentially anymore, but it's not flat either.

Here you go https://ourworldindata.org/grapher/consumption-based-energy-...

And that shows steadily increasing usage except during economic recession.

Re: Tidal energy is not renewable

#175

Post by joak »

codethief wrote: post #140
blake1 wrote: post #32

The single most important assumption in this paper is that energy consumption will increase by 2% per year. This kind of exponential growth leads to outlandish estimates for the amount of tidal energy that society will demand. Energy consumption has decoupled from population growth rates and economic growth. How much energy will we consume in 1,000 years? Most projections of the population have it stabilizing at arou…

> The single most important assumption in this paper is that energy consumption will increase by 2% per year. […] How much energy will we consume in 1,000 years I keep posting this link here on HN but, once again, it seems very appropriate: > The upshot is that at a 2.3% growth rate (conveniently chosen to represent a 10× increase every century), we would reach boiling temperature in about 400 years. https://dothemat…

This boiling temperature conclusion makes the assumption that we continue using thermal power (steam engines, etc...), where waste heat is around 60%.

However photovoltaic and wind does not produce much waste heat. Arguably solar and wind cannot scale 1000x but then you could have non thermal fusion like Helion's https://www.helionenergy.com/technology/.

Btw, thermal power is already showing limits (rivers overheating in summers), we don't have to wait 400 years to see its failure.

Re: Tidal energy is not renewable

#176

Post by JamisonM »

littlestymaar wrote: post #131
JamisonM wrote: post #127

Earlier quoted context omitted.

Do you have some data to back up this assertion? For me what I see in the numbers is that Chinese domestic quality of living improvements correlate better with increases in energy consumption than does US imports (or Chinese exports). What is also interesting is that China's "energy intensity" - energy used per unit of GDP is pretty flat, if wealthier nations were exporting energy demand via imports I would expect th…

You can find data related to this phenomenon when searching for “imported emissions”. But then it's only going to be related to the CO2 emissions, not energy, and the measure appears to vary a lot depending on the methodology (from a quick search, France is estimated to import between 117 and 750Mt of CO2 a year, quite a large error margin…). > if wealthier nations were exporting energy demand via imports I would exp…

> France is estimated to import between 117 and 750Mt of CO2 a year, quite a large error margin…

I don't know, if your basis for your opinion is that you googled it and you got some very wide ranging and contradictory results then that seems like a poor foundation to start with.

> Why? These exports from China generates GDP in China so it just grow the energy consumption as well as the Chinese GDP, making the ratio flat.

If the ratio is flat then there isn't really much of an export of energy effect in my view. If you are exports were dominated specifically by the use of energy (over say human capital or laxer pollution standards) that intensity would rise because it would be the source of the economic advantage. I.e. if domestic consumption trade 1 unit of energy for one unit of growth but exports trades 2 units of energy for one unit of growth intensity will rise if exports dominate the energy mix. That does not seem to be the case.

A huge proportion of US imports seem to be based on "assembly" from what I can tell, the dominant categories from China are electrical/electronic goods and industrial machines - most of the stuff is the assembling of US & EU (and Taiwan for semiconductor reasons) made parts.. the energy mix of the import-export dynamic seems like it needs a lot of analysis - I would like something authoritative that shows an attempt at an analysis, I can't seem to find it.

Re: Tidal energy is not renewable

#177

Post by midasuni »

joak wrote: post #175
codethief wrote: post #140

Earlier quoted context omitted.

> The single most important assumption in this paper is that energy consumption will increase by 2% per year. […] How much energy will we consume in 1,000 years I keep posting this link here on HN but, once again, it seems very appropriate: > The upshot is that at a 2.3% growth rate (conveniently chosen to represent a 10× increase every century), we would reach boiling temperature in about 400 years. https://dothemat…

This boiling temperature conclusion makes the assumption that we continue using thermal power (steam engines, etc...), where waste heat is around 60%. However photovoltaic and wind does not produce much waste heat. Arguably solar and wind cannot scale 1000x but then you could have non thermal fusion like Helion's https://www.helionenergy.com/technology/ . Btw, thermal power is already showing limits (rivers overheati…

Where does the energy go then? EM radiation leaving the planet?

Re: Tidal energy is not renewable

#178

Post by midasuni »

svnt wrote: post #165
blake1 wrote: post #32

The single most important assumption in this paper is that energy consumption will increase by 2% per year. This kind of exponential growth leads to outlandish estimates for the amount of tidal energy that society will demand. Energy consumption has decoupled from population growth rates and economic growth. How much energy will we consume in 1,000 years? Most projections of the population have it stabilizing at arou…

> gets us to about 150 trillion humans in 1,000 years I realize the big issue is settled here but just to scope this detail: the total land area of earth is coincidentally approximately 150 million km^2 At 150 trillion humans each human would get just about a square meter. Many of those square meters are uninhabitable.

That’s about the density of Kowloon walled city. And ignores the available space in the ocean.

Re: Tidal energy is not renewable

#179

Post by jl2718 »

codethief wrote: post #140
blake1 wrote: post #32

The single most important assumption in this paper is that energy consumption will increase by 2% per year. This kind of exponential growth leads to outlandish estimates for the amount of tidal energy that society will demand. Energy consumption has decoupled from population growth rates and economic growth. How much energy will we consume in 1,000 years? Most projections of the population have it stabilizing at arou…

> The single most important assumption in this paper is that energy consumption will increase by 2% per year. […] How much energy will we consume in 1,000 years I keep posting this link here on HN but, once again, it seems very appropriate: > The upshot is that at a 2.3% growth rate (conveniently chosen to represent a 10× increase every century), we would reach boiling temperature in about 400 years. https://dothemat…

When the nuclear apocalypse has passed, and the last remaining humans are living underground on mushrooms, somewhere an economist will claim growth using a model updated to include the work done by ants, and somewhere a bureaucrat will update the tax code to collect on it.

Re: Tidal energy is not renewable

#180

Post by xg15 »

dredmorbius wrote: post #166
blake1 wrote: post #32

The single most important assumption in this paper is that energy consumption will increase by 2% per year. This kind of exponential growth leads to outlandish estimates for the amount of tidal energy that society will demand. Energy consumption has decoupled from population growth rates and economic growth. How much energy will we consume in 1,000 years? Most projections of the population have it stabilizing at arou…

The lesson that constant percentage (that is, exponential) growth cannot continue endlessly is the fundamental message behind the concept of Limits to Growth. That is, there exist intractable limits to growth , and that no matter how convenient it may be to pretend otherwise, humans ignore this fact at their extreme peril. Long-term ongoing economic growth, expressed as a constant percentage, is baked in to most curr…

I think there is one escape from this, basically confining more and more "growth" to artificial numbers on paper (or in a DB).

Cryptocurrencies are kind of going in that direction, where the "value" that is reported as economic growth doesn't correspond to any kind of real-world matter or activity, but is simply assigned to some specific group of bits.

I can kind of believe that this virtual kind of growth could continue a long time without boiling the planet, but of course that doesn't make things less absurd, as the "value" would represent nothing objectively useful and would have to be maintained artificially - either through scarcity mechanisms like PoW etc, or through locked-down devices and ecosystems.

So that kind of "growth" could go on forever without burning the planet but would probably be a step back for civilization.

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