Ultimately, wind and ocean currents are driven by the 170,000 terawatts of solar irradiance continuously hitting the earth[1]. Human civilization uses about 17 terawatt[2], so we still have a ways to go before we get in the same ballpark.
(On the other hand, give it a few centuries of exponential growth and let's see where we end up.)
[1] https://news.mit.edu/2011/energy-scale-part3-1026 https://www.theworldcounts.com/stories/current_world_energy_...
[2] https://www.theworldcounts.com/stories/current_world_energy_...
But yeah, it will have an effect; the other question to ask is, how significant is this effect, and how does it compare to other forms of power production, e.g. fossil fuels?
The global warming caused by fossil fuels has a bigger effect on the oceans; with decreasing salinity due to the melting of ice caps / glaciers, the gulf stream is slowing down and will eventually stop, causing distribution of heat across the planet to stop, causing the northern seas to cool down and the southern ones to heat up.
Eventually the earth will be tidally locked to the moon (just like the moon is to the earth), and the moon will be in a higher orbit.
I guess the turbines will speed this up? As they’ll keep the bulge farther ahead of the moon.
EDIT: Wikipedia link https://en.m.wikipedia.org/wiki/Tidal_acceleration
Weirdly, the resulting pool of energy is pretty much the same size - wikipedia quotes the rotational kinetic energy of the Earth as being 2.138E29J.
So we're still talking about an insane amount of energy.
If you use 17.7TW as the total power consumption of all of humanity, if we were to somehow derive ALL of our energy needs from tidal generation, it would take 358 million years to deplete the rotational energy of the earth.
How's that? Can we consume it? What would be the reaction? Moon altering its orbit?
The sooner we stop using these feeble fossil fuels the better
Solar and wind are needed today, but Starship could bring launch costs down enough that some highly optimized space solar panels with microwave power beaming could be viable within a decade.
Solar panels in space is the believable part; rays of concentrated energy being sent back to earth is what I'm skeptical about. Besides, solar panels have a limited lifetime; I don't believe space solar panels are a cost effective solution to solving the energy crisis.
We’ll need to move into space sooner or later if we want to continue exponential growth.
(100% agree that getting into space is important, and that if we want to continue exponential growth we'll need more than one planet. In fact, we'll need more than all the planets and we fairly rapidly (in cosmic terms) hit the point where the available volume of our light cone isn't enough. Maybe indefinite exponential growth isn't something we should feel entitled to...)
Yes. The frequencies that are not blocked are called "atmospheric windows". And there is indeed such a window for microwaves. These windows also exist for visible light and a range of IR, but those depend more on weather conditions.
Maybe illuminate existing solar arrays during nighttime? Any other energy receiver would be so far behind PV on the price / manufacturing learning curve
I never thought about this. Is there some orbit where this becomes feasible?
The only way to preserve the Earth is smart planning, reducing energy usage and moving industry to the space. IMO Earth should be sanctuary for people to enjoy their origins and for some rich people inevitably. Most people should move to other planets or space objects where pollution does not matter.
There seems to have been a lot of extreme weather in recent years. Could it be because harvesting energy from the wind alters weather patterns? A lot of people would rather just blame it on global warming than ask a question that might expose a flaw in our plans to wean ourselves off of fossil fuels.
We need to have bit more humility and a bit less dogma about what we "know".
By contrast, there is no known way that wind power extraction, which is currently < 1TW globally, could possibly be destabilizing the energy system of the rotation of the Earth (which is what causes wind). That system contains ten billion times more kinetic energy than we remove from it annually.
The amount of kinetic energy the moon removes from the Earth's rotational kinetic energy every year is larger, and has been going on for a long, long time, so if it was going to cause fire weather that would already have been a long-standing problem.
In short, the amount of CO2 that humans have dumped into the atmosphere in the last 200 years is comparable to the amount that was in there to begin with. It can't be ignored. But the amount of energy we remove from the wind is nine or ten orders of magnitude smaller than the total amount that exists, and therefore it can be ignored.
> There seems to have been a lot of extreme weather in recent years. Could it be because harvesting energy from the wind alters weather patterns? A lot of people would rather just blame it on global warming than ask a question that might expose a flaw in our plans to wean ourselves off of fossil fuels.
Do you have anything other than wild speculation? Because in most cases slowing down air currents should calm the weather.
And of course this has been asked!
Energy races to heat. Heat tries to diffuse. If it can't, it's still there. Moving it still costs more energy.
Entropy always wins.
You could do some very basic napkin math multiplying the air displacement per turbine (or whatever metric you choose) and multiplying by every turbine that exists, and I'd bet that number would be nowhere near total air displacement from natural causes.
Human CO2 emissions matter precisely because the math has exceeded change from natural causes. And this happens because literally everyone is doing it. IF we cover the planet in wind turbines the same way we cover it with waste C02 then maybe you might have a case.
Not to say renewables aren't without their issues. There are likely a whole host of second- and third-order issues there that have yet to be discovered, let alone resolved. But we would need adoption on a scale far beyond what has been proposed to combat global warming to approach that.
> Human CO2 emissions matter precisely because the math has exceeded change from natural causes.
Why? It's the significant detrimental impact of the human activity that's important, not how it compares to the amount or change from natural causes. (It doesn't even matter that it's human activity. If Earth were going to become inhospitable by entirely natural causes, that would still matter.)
> then maybe you might have a case.
I'm not making the case that wind turbines are harming the environment; that's just the example at hand. I'm making the case that casually dismissing (questions about) the potential impact of human activities is wrong.
(Maximum flow of 65 sverdrups = 6.5e7 m³/s, and a top current speed under 1 m/s. Density of water is 1e3 kg/m³, and there's also a subtle multiplicative factor of 0.6, from Betz's law).
[0] https://tos.org/oceanography/assets/docs/28-4_andres.pdf ("Mean Structure and Variability of the Kuroshio")
https://en.wikipedia.org/wiki/Sverdrup
https://en.wikipedia.org/wiki/Betz%27s_law
*(Footnote because this stood out to me as weird, but the math holds up: the amount of heat energy transported in ocean currents is >10⁴ times greater than their kinetic energy (what ocean turbines can extract). 1 kg of water stores 4,200 J per 1 °C temperature increase, but only 0.5 J of kinetic energy at 1 m/s. So I think that blocking an ocean current would have a disproportionate amplifying effect on the climate. IANAO).
https://www.bloomberg.com/news/features/2022-05-30/japan-s-d...
- "Japan’s New Energy and Industrial Technology Development Organization (NEDO) estimates the Kuroshio Current could potentially generate as much as 200 gigawatts"
They won't.
If it is a analog to wind turbines, the math will bear it out, but it’s a perfectly valid question to ask.
It’s sad that this is such a common argument against progress. Where do people learn to think this way? Does it come from education? Failures in life?
The concern is that more information should be discovered about the effects, and that is usually done through experimentation.
> ”Where do people learn to think this way? ”
Where do people learn to create straw man arguments instead of actually replying to what was said?
"The grass is always greener on the otherside."
I believe that's where this line of thinking comes from.
Have you ever tried to change lanes because yours isn't moving, just to find that right after you change to your new lane it stops and your old lane picks up again? Man that sucks
People who think like that are seen as serious people who don't foolishly ignore all possible negative consequences.
I, as the reader might guess by now, don't have high hopes for societies that function this way.
As it turns out, there's a LOT more we can do now (that is actually hard work to boot) than we've necessarily been able to do before.
If you actually take the phrase "reasonably forseeable" seriously, I assure you, chasing down those nasty little details and feeding them through the math takes a hot minute.
Powering a city is at another entirely different scale, and “diesel” doesn’t come close to addressing the magnitude of that problem.
Paradoxically, we would effectively be saving those currents using a fraction of the energy in those currents themselves.
Using these turbines would be a drop in the ocean and a smart move if it helps us tackle the big offender. We should get on it soon though, if we let it get to a point where thermohaline circulation falls apart using currents this way may no longer be an option.
I suspect that adding more drag to the tides could either boost this process or reduce it, depending on the timing of the energy harvesting.
I would also say I'm not a big fan of the activists' line of thinking that artificial changes in the ecosystem being bad (but man-made "conservative" actions are good). I mean you can't possibly prove that and we're way pass "should we alter our environment?"
seems like an interesting possibility to recapture some of the loose climate energy that we want to pare down
The entire humankind's power consumption is completely microscopic in comparison to any natural weather phenomena.
We are 0.0000000000001% of energy the Earth dissipates.
Interestingly this was a real concern before testing the first nuclear weapons.
Some scientists were convinced that the chain reaction would ignite enough of a fraction of the atmosphere causing irreparable damage. That concern was ignored because these weapons were critical for the war, and luckily nothing like that ended up happening.