http://nextbigfuture.com/2011/03/maximum-wind-and-wave-power-limited-by.html


So... yeah. Fail.

Can someone dumb this article down a bit? I get the general idea, but more layman terms would be appreciated.

My computer is powered by wind.

Edit: From what I read - skipped through the details of their 'three methods' - it sounds like wind power isn't nearly as effective a power source as originally thought, and if we managed to get as much wind power as we could, it'd mess up the climate (as they said in their example to get 10-68TW of energy it'd be like "doubling the amount of CO2 in the atmosphere").

We won't need it if we just build freaking Thorium reactors.

http://en.wikipedia.org/wiki/Thorium#Thorium_as_a_nuclear_fuel

Maximization of wind farm usage is unsustainable, basically. We wouldn't be able to replace our nastier fuel sources with wind farms completely. Not exactly what I expected would be why wind farm usage wouldn't be maxed out. (Always figured land-acquisition and paying for it would hold wind farms up)

Well frankly I've had the idea of this possibility stuck in my head since a long time ago. The climate on the Earth (and on any other planet/moon/whatever) is basically particles going around. Particles cooling off, getting heated by the Sun, blah blah, which all ultimately results in the entire atmosphere having this bunch of kinetic (among others) energy. Then we come and build wind farms, which produce electricity from wind. That obviously must be svcking up that kinetic energy from the atmosphere. Do enough of that, and you obviously must end up screwing up the climate. :shrug:

The wind towers are big and ugly anyway.

Don't get me wrong, I'm majoring in Environmental Biology, I want to shift to sustainable fuels (and fuels that don't harm people - like coal burning releasing all those heavy metals and chemicals that get into our fish and make our rain acidic), but wind really isn't the silver bullet, or even part of the silver bullet. It only really works as a good alternative under very specific circumstances/conditions. As for solar - the technology is too expensive, and, again, it doesn't work year-round further toward the poles where half the year the sun is as weak as a kitten.

I'm still waiting for http://news.bbc.co.uk/2/hi/science/nature/8485669.stm....

I don't think there's any really good energy source that will solve all of our problems. Much like Veeno I also had mild suspicions there would be problem with "environmentally clean" energy, just because we haven't used it much before and don't know all of the details.

And besides that, the efficiency of the best, top-notch and most expensive solar panels available today is only 18 [censored]ing percent. That's tragic.

What's even more tragic than that is the way nuclear energy is used in nuclear power plants. (I bet some don't know that either.) See, that's fun: the nuclear energy of the radioactive thing heats up water which evaporates into steam which turns the turbines which generate electricity. BRAVO, MANKIND, BRAVO!!! :facepalm:

Not everyone has Elerium 115 laying around.

I am glad you agree with me about the article. I assume you were talking about the article there.


It seems to say there is serious consequences of using renewable energy to generate 70TW. However, same with fossil fuels. Take something to its logical extreme and you get serious consequences.


However, given that we only use about 0.3% of the energy we get from the sun, heh. Build solar panels in the Sahara and we remove a lot of the energy problem without causing issues.

Basically they discuss a "top-down" way to calculate the total amount of wind energy available.

Other peoples' "bottom-up" calculations just state that the windmill taps energy from its wake, i.e. the air directly behind / downwind of it. But otherwise the 'bottom-up' models allow for the building of as many windmills as needed, as long as they aren't in each others' wake. The energy in the weather system as a whole stays constant in such models - which is silly really, there's no such thing as free energy.

In this article, they instead calculate a maximum amount of power transferred from the Sun to the wind, and give that number as an absolute upper limit for wind power. This gives much smaller available power than the bottom-up method.

The top-down method intuitively makes more sense - you can't get more energy out than actually goes in.

I think they make a good case for wind power alone not being the solution to our energy needs. However, I don't think anybody really believed that ONLY wind power would ever be sufficient, so that's kind of a moot point.

They also suggest that too much usage of wind power might have environmental effects. I think it's important to get some limits on how much wind power we can safely use. More work obviously needs doing on this last point - a 'back-of-the-envelope' (their words) calculation like the one shown in this article seems too superficial to use as a limit.

Also, I'm guessing there could be some kind of feedback they haven't accounted for, i.e. what happens to the percentages shown in their fig.1 if we start tapping a substantial amount of energy from the wind system? There's a lot of solar energy up for grabs, after all.

I think wind power is better on a smaller scale, like single turbines on your property to power your home or at least part of it.

People finally starting to realize that there is no such thing as renewable energy? :foodndrink:

True at the moment. However, if in the semi-near future every single home in the world were to be powered by its own turbine (or a couple of them), things would quickly escalate into a cluster[censored], climate-wise.

Biofuels from algae would be cool. I remember hearing about how there's research being done for that. Switchgrass is another potential source for a plant-based biofuel (since corn is 1) food, 2) requires lots of inputs (fertilizer, land, water, etc.)). Switchgrass grows happily on its own with little inputs, it has nice deep roots (good for the soil), and can grow on marginal land that couldn't be used for crops.

@Veeno: laws of thermodynamics svck. Nothing is 100% efficient. I think combustion for vehicles is only 15% or so efficient (i.e only about 15% is put toward making your car move), so 18% for solar/photo voltaic isn't too shabby. Even plants' photosynthesis isn't as efficient as you might think: 25% is the theoretical limit (http://en.wikipedia.org/wiki/Photosynthetic_efficiency).

I think we should dump all the spent nuclear fuel on the moon. Or mars. Make NASA out nuke garbage men, it isn't like they're doing anything more important with their aging shuttles. Might as well smash them and their payload into some distant planet. (note: tongue-in-cheek)

And it's so frustrating that you can't synthesize it. You have to gather it from the aliens.
I think this is the surest sign we need to fund the military to better their combat and recovery programs.

*checks to see if my secret bases are still hidden*


A couple of months ago I saw a sort of documentary on television stating that using windmills costs even more fuel than not using them as the wind fluctuates too much, so the old fashion power plants constantly have to adjust to supplement the power generated by the windmills. This means that the power plants don't run at their most efficient level and constantly waste power by throttling up and down..

but it's not like I'm an expert on the subject and I have no idea if that was founded on actual facts since it was in a program where people where complaining about a windmill park being build next to their town (so it could be rather one-sided).

Is this really the first time anybody's thought "Wait, wind energy takes energy from the wind?"

Hell, $/MW, wind energy is inefficient as hell. New-design nuclear like thorium reactors takes the top spot, by quite a margin.

Wind has been running into things and expending energy for ages - buildings, Trees, Hills, the ground, other airmasses, and it hasn't gone anywere. Guess what, when the air hits these things, it expends energy, kinda like hitting a aerodynamic blade.

As the amount of wind turbines we'll be nbuilding is a heck of a lot less than the number of trees, hills, buildings, etc already in existence, this makes no sense at all.

I'm a glider pilot, without the wind I'm limited to flying for a few minutes AND wind turbines are annoying for us (They're on good hills with their aircraft-killing blades). There's plenty of good reasons to hate wind power, but this doesn't seem to make a bar of sense.

The Sun will keep heating up the earth unevenly. Uneven heating causes different areas to have different air pressures. Air will continue to rush from areas of high air pressure to areas of low air pressure. The Spin of the earth will continue, as the air doesn't move as fast as the ground does you'll still get the same pervailing winds as you always. Sticking up a few extra whirly-blades isn't suddenly going to change this.

Unless you're somehow using wind power to stop this or power a death ray... I really don't see how wind power can do any "Damage".

Lets see, without having to look at science, the fact that the government had to intervene and subsidized the living hell out of it in order for it to be produced should make people think it was a bad idea. Looking at the science, it's very inefficient. May as well use ethanol, which requires more energy to make than it provides!

I'm just angry that nuke plants are going to be pushed another 50 years back, at the very best, because of what happened in Japan. Never mind that the specs today make the current 1970s models look like a wooden and highly flammable water mills.

The big problem there is the thought....... "well, what if you have a launch accident/etc? Blowing up the payload of nuclear waste at, say, 15-20 miles up in the atmosphere would svck."

The problem is that unless we discover magic, in order to provide enough power continually just through wind we're going to have to cover a significant portion of the planet. You cover a lot of the planet, and yes, it will start having ecological effects. Same with solar power - that sunlight isn't wasted, and solar cells simply aren't efficient enough, nor is sunlight constant enough to be able to rely on it. However you put it, there's no such thing as renewable energy - everything comes from the sun, and we only get so much energy from that, and we *can* use it all. Indeed, if current growth estimates hold there will come a point in the not-too-distant future where we use more power than we *can* get from the sun (Well, without a dyson sphere, but we're not quite there yet).

Renewable energy can't carry us alone. There's simply not enough energy in the system. Obviously it's not a concern now, but if we start ramping up wind power to the point it actually provides a significant amount of global energy usage, there will be effects.

edit: Also, dumping nuclear waste on the moon is an awful idea - the cost of failure would be unthinkable, and nuclear waste isn't useless, we can use it as fuel.

I was under the assumption that we had achieved 30ish percent efficiency on solar panel technology. Wikipedia has it listed as approaching a theoretical 29% limit.

That said, my idea was always this: a government subsidized building code that required all new homes and commercial structures to have at least one solar panel installed on them connected to the power grid. All old homes would receive a tax credit for retroactive installation of solar panels. In this way you could easily gain hundreds of square miles of solar cell connected to the power distribution system, spread out in enough varying regions that weather wasn't even a large factor.

As for nuclear power, how else is it gonna work?

I mean you only have so many ways to produce a voltage, and the most effective is using magnetic fields in turbine generators. The only other way nuclear fuels could be used is with gigantic thermocouples, and even then it's not as effective as the steam. Plus you need water to cool the damn thing.

It's all quite effective, although civilian plants are generally old and ridiculous. Boiling off coolant, really.

What we'd need is some breakthrough in fusion technology that made it sustainable. We can achieve nuclear fusion, but it takes entire buildings filled to the brim with massive capacitors to even start the thing and get a second long bright flash of fusion before the thing is out of juice and needs to recharged for the next month.



Pfffffffffftbtht.

Nuclear explosions don't work that way. You need highly enriched uranium or plutonium that has neutrons fired into it through a screen of heavy water to slow the neutrons down, because if they move too fast they won't catch and won't cause enough atoms to split.

Nuclear waste from reactors isn't even the same element. It couldn't EXPLODE if we tried to make it.

With Solar, it is just a question of efficency, and there was a nice scientific chap on John Stewart recently who showed that we're on track for solar to be more than efficient enough to power pretty much everything by 2018.

I used to be pro wind - even if its inconvienent for my hobby, but the places where its good often seem to involve a lot of cold in those winds it needs... Theres cases here in the UK of Wind Plants consuming more than they produce in the year to prevent cold damage in the winter.