CaptainPanic

Almost... Of the people who are interested in the news, the majority probably just want the facts. But I'm afraid that the majority of people simply aren't interested in the news. The majority of the people prefer Your Next Top Talent Show, or the 8 o' clock sitcom. That's in the US, but in Europe as well. I am afraid that for many people, the news is just a way to fill some time where they'd otherwise be bored. In the underground (also called the metro) people read rubbish newspapers. Why? Not because they care about the news, but because the alternative is to be bored. This means that there are a lot of readers who aren't very critical... as long as it's available and for free.

You can transfer power without too much losses through DC lines over long distances (the longest line at the moment is 580 km, from Norway to the Netherlands). In the case of this solar tower, it's just 50 km from Seville (Spain). I guess that's close enough to go straight to AC and just put it on the regular grid.

Exactly. If you have enough sunlight (direct, not diffuse) and space, this thing is brilliant. I wonder if you can look at the tower without sunglasses? I guess not. What is it like to have such a bright light (in addition to the already bright sun itself) as your neighbor?

Although it's undeniable that it will cool down, this is for sure negligible. In the pdf that you supplied, we can read that the tanks can contain up to 800 MWh (2.88*10^12 J) of energy (in the form of hot molten salts). If you want to lose 1% (2.88*10^10 J) of that heat into the surrounding air, you would need to heat nearly 30 million m3 of air by a degree. If you do that over the course of 1 day, you heat up 333 m3/s by 1 degree. I just don't think so. I can't prove it, but I think losses are way less than 1%. In fact, it's only 17%. The reflective area is 304750 m2, on a total field area of 185 ha. And the mirror coverage might well be less than that of the 3-year-old plant. Are you sure that 120 MWt is the 24-hour-average? Because if it is peak power (and that makes more sense to me), you need to put that into your little calculation too: 20 MWe / ( 120 MWt*(percentage of time that the tower receives light)) = 20/(120*0.5) = 33% The 120 MWt is a very ambiguous number... it can mean many things. It can mean peak power (highest power at the sunniest day). It can mean an average day power. It can mean the average power during hours of sunshine. In a coal power plant, MWt is simple, but those have a continuous process... this does not.

This sounds like such a specific question, that it is probably better to make a phone call to an expert (I advise you to try a local university). But you never know... maybe someone on this forum actually knows this.

The molten salt loop obtains heat from the sun, and transfers that to water (and forms steam). That part is not limited by the Carnot efficiency. In fact, it has a theoretical maximum of 100% efficiency. With enough insulation and negligible friction in tubes and equipment, every single Joule of absorbed radiation can be transferred to the water/steam. The salt only transfers the heat, because it is not practical to place a boiler in a tower, and because molten salt can store a lot more energy (heat) than steam, which is practical in the night when the sun does not shine. The 40% efficiency comes from the only Carnot efficiency (there is only 1), which is found in the steam cycle. Also, with 565°C of the molten salt, you should be able to make steam of at least 500°C. It's a liquid-liquid heat exchanger, and it should be pretty efficicient. And that means that your Carnot efficiency is: [math]\eta=\frac{W}{Q_H}=1-\frac{T_C}{T_H}=1-\frac{273+50}{273+500}=0.58[/math], or 58% I've assumed a cold reservior at 50°C because we're in Spain in the desert, not at a moderate area where a much colder reservior would be possible. There really is no point in creating a molten salt of 565°C if you do not intend to make steam of a very high temperature too. I know that 500°C is in the supercritical range, and that's why I've added a link (here) to an article about supercritical heat cycles in coal power plants... anticipating a question to show that's normal technology... So, to arrive at 40% overall efficiency, with a Carnot cycle that has a theoretical maximum efficiency of 58% (I know that it's lower in reality), we should get a minimum of 69% (0.69*0.58=0.4). When reality is taken into account in the Carnot cycle, we must conclude that the actual efficiency of the molten salt cycle must at least be higher than 69%, (the only alternative is that we call these people a bunch of liars optimists). This in turn means that the absorption efficiency of the heated surface is very likely higher than the maximum of the solar boilers (74%) that I posted earlier. Sure, it is not 100%... but it's pretty high nonetheless.

I think that the Dutch situation is quite similar to the UK, with the BBC. In the Netherlands, we have had (and still have) what wikipedia translates as "pillarization" (verzuiling), which is a form of political segregation. Leftist-socialist groups have their leftist-socialist newspapers and radio/tv channels... and religious groups had their religious (Catholic or Protestant) newspapers and radio/tv channels. There is a liberal, or even capitalist paper and channel too. And all those are supported by political parties. So, in a way, we have a similar situation as in the US, but then with more groups (not just the democrats and republicans). But in addition, since more than 50 years, we've had a relatively objective and independent organization for news and big events: So, while we have plenty of organizations, both private and publicly funded, who give a lot of opinions, we have at least 1 organization that has a task to inform the public. Obviously, they receive comments about not being objective - especially when something bad is reported about a particular political party, they will be accused of choosing sides... but in my opinion, they are doing a reasonably good job. As good as can be expected with limited means and funds in a strongly opinionated world. Btw, this should not be confused by a "State-owned news agency". It is state-funded, but not state-owned. They have no obligations to the government or any political group, except that they must (by law) inform the public.

Selective coatings exist (used on industrial scale in solar boilers) that are good at absorbing sunlight, and emit little in the IR spectrum (which is what they aim at, because they are used to make hot water). Obviously, if you do not remove the hot water (i.e. there is no flow), then soon enough every solar boiler (and in fact every object in the universe) will increase in temperature until at some point the emissions are equal to the absorption (although not necessarily the same wavelength). Equilibrium must be reached, because otherwise it would heat up indefinitely... and the goal of the solar power thing in Spain is to get as far away from that situation as possible. So, the solar boiler absorbs light, but will emit little IR radiation, and thereby converts a lot of light into heat (up to 74% according to wikipedia). Naturally, an ordinary solar boiler is not the same as this molten salt thing in Spain. Most importantly: the surface area which is exposed to the outside (where there is no insulation) is relatively small in the Spanish molten salt thing. Therefore, radiation gets little chance. It is vitally important that you make a heat balance for this discussion, and you cannot dismiss the flow of molten salt. Most of the material which is heated by the mirrors is nowhere near a location where it can emit much.

About reflectors: high quality coatings (effectively mirrors) already can reflect nearly 100% of the energy from the sun. The question is what you do with this now: 1. Make electricity 2. Make heat (and then possibly electricity, or you use the heat) Don't look at those Archimedes death rays too much. That's all funny for Mythbusters and such, but it is completely pointless to adjust your focus point in a practical application to make energy. That archimedes death ray can hit a moving object with concentrated solar power... but unless your name is Archimedes, why would you want to do that?? The place where you want to focus the energy is always the same (just make sure it doesn't move), and sun rays are always parallel to each other...

I had to laugh when I read this. I just wanted to share it with you all. Fox News Viewers Know Less [about the news] Than People Who Don't Watch Any News: A Study

Once the gap between poor and rich is so huge that the rich indeed pay a disproportionate part of taxes (because of an even more disproportionate income!), it makes sense not to support anything tax based, and to privatize everything. If you are rich and you pay tax, you pay your own education, library and security, but also the education, library and security of the much poorer neighbor. If it's all privatized, you pay your own education, library and security, and you have extra money for a nice swimming pool, and screw that neighbor. The core of the problem therefore is the huge gap between rich and poor, and our selfishness. The first can be changed. The second, I'm afraid, is just in our nature.

Many of us want those turned private too. Yay Ron Paul! Private roads? Seriously? How far should that go? Just the highways, or all the roads? I've never heard of the concept of a completely privatised road system... it's fascinating, and scary. Companies control your mobility. It's the ultimate capitalist dream, but I fail to see how it can work. So, let's assume that we want to privatise all the roads, including sidewalks and bike roads, how would that work? Can we privatise rivers too? Because how can a road company compete with a river? And if you don't pay, you cannot use the roads (even on foot)? How could a sidewalk be profitable? So many questions. And if you decide that you don't like the company that connects to your house or your local shops, can you then build your own road in parallel? How do you even get any competition (you can't privatise something without enabling competition)? I really fail to see how this does not turn into a giant monopoly position for various companies, and who the road company wouldn't just charge enormous prices for a passage on a crappy old road? Would a government be allowed to control the prices (how can you have competition with a government that tells you what you can and cannot do)? And I think it goes straight against human rights (article 13.1) that you have a freedom to move around without having to pay someone all the time. I know this is going totally off topic, so I have reported my own post, and I've proposed to split this off as a separate thread.

LOL No, it's not irrelevant. Brain exercise is ok, but in my coffee breaks I like to get the reward of actually solving a problem. It needs to have a beginning, and an end... not only a beginning.

If you don't believe that people can go to the moon... does that mean you also don't believe that airplanes can go 900 km/h, at 12 km altitude in quite low pressure... and do that for just 50 euro per ticket (if you book at the right time)? Because, a lunar lander is essentially just a similar pressure chamber, but with bigger and more complicated engines.

Are you serious? I always thought your write your posts in this style because you try to lure us into writing a long fantasy story, where all members write a paragraph or something.

It wouldn't burn up, but 6% extra energy reaching the surface of the earth would most definitely screw up the climate. Our average temperature on earth might increase just 5 degrees perhaps... that's still enough to change everything. And in addition, every year, we would have a period where the night just does not get dark, because Jupiter would be shining on the now-not-so-dark-side of the earth.

No. Just look at Europe. Most European countries have multi-party democracies and coalition governments. But at the same time, we have effective governments. I know that a few examples are not enough to extract a rule, but in this case we have little else to go on.

The problem is that in the US 2-party system, there isn't much to stand up to. You can't stand up if the only other 2 choices are (1) not voting or (2) something almost the same or even worse. The Democrats aren't much better than the Republicans, in all fairness. Sure, the blame is not one-sided. The voters are interested in irrelevant issues. And the politics/media happily supply irrelevant information, because that will never harm their campaign, and can often only hurt the opponent's campaign. I did not say that I want the Tea Party in power. I said I want them to split off from the Republican party, because three parties is better than just two, regardless of what that third party represents. As long as it attracts some voters, you're onto a possible multi-party system. It could kickstart a change in US politics with more parties getting a chance, and that only gives voters more power. And that's the goal I had in mind. No matter how coorporation-focussed the Tea Party may be, if they split off from the Republicans, that would be a very democratic move which all the voters should appreciate (imho). At the same time, I think that it would be a complete disaster if the Tea Party would have a majority in the houses in the US, or if they would supply you guys with a president. So, I see them as a way to improve democracy in the US, even though I disagree with each and every word in their program.

I do not think that there are any politicians who aren't primarily trying to help themselves. Actually, that in itself is not necessarily a problem. The ideal voting system should ensure that they think of the voters. This prevents them from doing anything really stupid. In the US however, there are so few swing states, and the number of votes that are practically guaranteed to both parties is so large, that a party can have the arrogance to ignore their voters. All they need to do is to convince a relatively small number of undecided people what to vote. Or, alternatively, they can just cheat. Also, voters got themselves to blame because they interest themselves so much in the martial status, and any sexual escapades that a large number of capable leaders are just not suited because of some previous life... and a large number of topics just never get discussed because the focus is elsewhere during the elections. What the US democracy really needs is a third party to get big. Or a couple of new parties to get big. It's really a pity that the Tea Party is not getting any bigger, and that they (for these elections at least) seem to get along with the other Republicans quite well. It would be a blessing for everyone if they would split off, forming that 3rd party. I think a good democracy has at least 5 parties that can all be in a government, and that can all deliver a president. Then you have something to choose, and then the politicians have to listen to their voters in more detail. There is one danger in a multi-party system: if all the parties get divided into a very simple left vs. right discussion, then politics will get as silly as the US's. Two options just isn't enough.

So, I'll be famous now?

Ok, I admit that the marbles were a poor example. Still, the random motion of molecules is one of the reasons for disorder, especially for gas phase systems. Obviously, if you know more about it, then the random motion is far from the only phenomenon involved. All kinds of attractions between particles make the motions less random (especially in liquids and reactions), and these influence the mixing behavior. But it's pretty difficult to explain entropy when you take an example of a system that actually ends up demixing itself (e.g. oil and water), which is why I didn't choose it as an example. Of course, the laws of thermodynamics still count. Entropy still increases... but it's a lot more difficult to understand. Damn, it's always a thin rope you're walking in this forum. Oversimplify, and you get (rightly) corrected by others. But make it too complicated and others just fail to understand it. I figured the level in this thread was that of high school, so I chose to approach it in a simple way. It might have been a wrong approach.

As far as I know, we cannot measure anything about that... so it's just a theory, but unfortunately a theory that we cannot test. In my opinion, that makes it no better than a fairy tale.

Because you are an engine that produces about 150-400 Watts of power. Most of that is finally lost in friction internally (for example, your heart pumps the blood around but the blood vessels create friction). So, chemical energy (your slice of bread with cheese), becomes kinetic energy (moving blood), becomes heat (due to the friction). And now you need to get rid of that heat. If your body is the same temperature as the outside (i.e. you are 36°C, the air is 36°C) you cannot get rid of the heat at all, except through sweating (evaporating water costs energy). If you do nothing at all (you have about 150 W of power at rest), you would have to sweat 230 grams of water per hour just to keep cool. Moist heat is even worse: the sweating doesn't work so efficiently anymore. And at 100% humidity and 37°C, you have no methods left to cool yourself at all. Sweat does not evaporate anymore. So, at higher temperatures, it becomes difficult to get rid of our heat, and that feels uncomfortable. But your body can adjust/adapt a bit. You can get used to heat.

No, they do not say that. Please show a reference when an evolutionist says this gets violated. Sure, life creates order from disorder (a plant seems a pretty ordered structure compared to the water and CO2 that are the building blocks). But at the same time, elsewhere the disorder is increased. If you look at the whole picture (including everything), then disorder increases. Statistics of molecular motion. Particles have a random motion (because they bump into each other). That just leads to disorder. You can test this at home: Take 2 types of marbles, of identical weight and size, but a different color, and place them in a bucket. Put all the marbles of 1 color at the bottom, and all the other ones at the top. Close the lid, and shake. I guarantee that before long, they're pretty nicely mixed... and that is what we call disorder. So, the reason is pretty basic: it's because particles move. The particles find an equilibrium, which (usually) is the situation where they're well mixed. I dunno. I don't know much about astronomy, or cyclic universes. To put it really simply: you are left with some heat that you cannot use efficiently. Heat is still energy, but when something gets close to the room temperature (= when the difference between the hot material and the outside environment is really small), it becomes pretty useless.

In fact, I am not 100% sure. Perhaps some biology experts can shine their light on what happens to bacteria or other microrganisms when they are being sterilized? What phenomenon is it that actually kills them?