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Tidal energy is not renewable
221–230 of 350 posts
Re: Tidal energy is not renewable
#222Earlier quoted context omitted.
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…
> Long-term ongoing economic growth, expressed as a constant percentage, is baked in to most current orthodox economics and economic policy. Whether it is or isn't, the optimal strategy for a nation is likely exponential growth until it can't, and then switch as quickly as can be done with the least problems. Since nations are competing, and we're talking about exponentials here, the cost for cutting off exponential…
> Since nations are competing, and we're talking about exponentials here, the cost for cutting off exponential economic growth too soon is likely to become irrelevant to the future, which every nation is going to strive to avoid.
I question this definition of relevance. To me, relevance is having a healthy, happy, sustainable society and culture. It's not accumulating goods and energy consumption in a self-destructive and planet-destroying way. The sooner nations realize this, the better.
Re: Tidal energy is not renewable
#223The 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…
> Long-term ongoing economic growth, expressed as a constant percentage, is baked in to most current orthodox economics and economic policy.
As a forecast which may or may not happen? Yes.
As an actual outcome that has been decided a priori? No, not at all. Only planned economies tried to do that.
Re: Tidal energy is not renewable
#224The 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…
15 billion as a stabilized population of the Earth is actually a very high estimate. Some estimate the curve will flatten at 10.5bn. But it is all a prediction, so who knows.
https://en.wikipedia.org/wiki/Projections_of_population_grow...
Re: Tidal energy is not renewable
#225Earlier quoted context omitted.
More countries are now sub-2.0 replacement, China is down to 1.09 so the peak is unlikely to get much more than that.
The trends are mostly encouraging but there are still 102 countries with a fertility rate above replacement rate, so we’re not out of the woods yet: https://en.wikipedia.org/wiki/List_of_countries_by_total_fer...
2.1 is the replacement rate for well-developed countries. It does not apply universally to all countries.
For example, the US had a fertility rate of 7.0(!) in 1800 and saw no significant population growth due to births because most of those kids died well before reaching the age of reproduction.
Historically, fertility rates have always dropped once basic standards of living have managed to get rid of excess child mortality.
Re: Tidal energy is not renewable
#226The 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. There's a 2nd big assumption: That tidal energy extracted is additional Earth's rotational energy loss above what Earth does by itself. According to the paper, tidal energy is dissipated through friction between ocean water & the seafloor. This dissipated energy subtracts from Earth's rotational energy. And s…
It's a bit absurd the idea that humans living on earth are going to produce more energy than the Sun.
Maybe I'm naive and simple minded. But that just seems insane.
If I'm doing the math right, at 2.3% growth = we produce more energy than the Sun in 4500 years.
It doesn't matter how many years it is. It's never happening.
Just look at how damn hot and inhospitable the sun is. We're not producing more energy here!
It'd be infinitely more plausible to build a Dyson sphere around the Sun, and call me naive on that, too, but I'm skeptical that's ever gonna happen either.
Re: Tidal energy is not renewable
#227Earlier quoted context omitted.
The UN has revised peak projections down several times; the peak is now expected at 10 billion.
Almost every human population is under strong selection pressure towards having more people. This dip in fertility cannot and will not last.
Then why aren't people in countries with plenty of resources breeding like rabbits and are we actually seeing a decrease in fertility once people get access to proper healthcare and sufficient food?
It is almost like humans are not mindless animals who solely reproduce because of biological urges or something.
Re: Tidal energy is not renewable
#228Earlier quoted context omitted.
But capturing wind surely creates a local warming effect? I believe I read that somewhere. Enough wind energy could accelerate global warming.
That energy is already present in the environment, as kinetic energy of wind, which will ultimately be reduced to entropic heat. A wind turbine doesn't affect that fact, though it may change the location at which the kinetic -> thermal energy transformation occurs. The more likely impact would be of wind turbines removing sufficient energy from wind that thermal transport of the atmosphere itself is disrupted, though…
Yeah I was specifically considering that reducing the "windiness" of an area would increase the temperature
> A 2018 study estimated that generating electricity demand with wind power in the United States would warm surface temperatures by 0.24 degrees Celsius
https://www.instituteforenergyresearch.org/renewable/wind/wi...
Re: Tidal energy is not renewable
#229The 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…
A global cooling system is easily conceivable. The ISS uses radiators to dissipate heat into outer space. We could do the same. We could concentrate heat with heat pumps and pump hot steam, molten salt, or plasma up a space elevator and radiate the heat away.
Edit: The link points out that in 1,400 years we'd be using energy at the rate produced by the sun and in 2,500 years at the rate of the entire Milky Way. Even if we solved the heat radiation problem, it seems unlikely we'd be able to obtain fuel for our fusion reactors at a sufficient rate given the speed of light and the density of matter in the universe.
Re: Tidal energy is not renewable
#230Earlier quoted context omitted.
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…
> Long-term ongoing economic growth, expressed as a constant percentage, is baked in to most current orthodox economics and economic policy. Whether it is or isn't, the optimal strategy for a nation is likely exponential growth until it can't, and then switch as quickly as can be done with the least problems. Since nations are competing, and we're talking about exponentials here, the cost for cutting off exponential…
One problem with "grow quickly, then switch", is that it often leads to high-growth institutions, factions, ideologies, and infrastructure.
Countries which grow quickly bake those assumptions into financial, industrial, economic, and political policies. They create companies, regulatory bodies, and financial systems which are predicated on growth. They create economic ideology and the mechanisms for promulgating it which are founded on growth. They create development patterns (most especially of urban land use --- the most massive impact of the automobile was on city and suburban landscapes), and consumption patterns.
Once entrenched, those are all exceedingly difficult to dislodge.
I'd argue that China is wrestling with this now, and that a fair bit of the disruption of the past few years (above and beyond exogenous shocks, notably Covid-19) involve this, as the CCP attempts to wrest power back from industrial, financial, and real estate interests.
Some European countries (notably the Netherlands and Amsterdam with its bicycle- and transit-centric transport planning), Japan, and possibly others such as Costa Rica, seem to have followed a lower-growth curve. These may actually find transition more viable.
At the capital of capitalism, the United States, transition faces absolutely massive obstructions in the form of politics, politics-expressed-as-social-values, economic interests, finance, real estate, land use, transportation, building codes (residential, commercial, and industrial), and more. Those are far more significant obstructions than actual technical solutions, and the more illuminating advocates of sustainability that I follow tend to emphasize this.
(I'll list these later, though I'm still waiting for XorNot to cough up. I'll give them a few more hours.)