environmental footprint of a large solar farm is worse than that of an oil-rig or gas mine
The problem with both of those is they produce pollution both at the point of production and the point of consumption.
The idea of 'green' also hinges of 'renewable'. The supplies of coal, oil, gas and fissionable materials is severely limited, whereas the components needed for production of solar panels are significantly more plentiful.
What I was referring to wasn't the movement of the hydrogen, but rather the use of the energy produced from the second reaction to power the first. This violates the second law of thermodynamics. It may be easiest to understand this using Lord Kelvin's formulation: "It is impossible to convert heat completely into work."
The heat (energy) produced by burning the hydrogen cannot be sent back to help produce the hydrogen (work) with 100% efficiency. Some of the produced energy will be lost.
The idea you had is even more preposterous: Of course you can't move hydrogen from one point to another without using energy; causing anything to start moving costs energy.
even if it is only hydrogen then its hydrogen from the air meaning you get (286KJ - inefficiency/mol) for every mol of starting water. What do you mean by 'from the air'? Extracting hydrogen from the atmosphere is not easy or cheap energy-wise, which is why they are bothering with the whole water-to-hydrogen malarkey to start with: it's one of the easiest ways to get hydrogen that they can then burn.
Your quoted number of 286KJ/mol: If that is the amount of energy produced by converting H and O2 into water, you need at least 286KJ/mol to convert water into H and O2 to start with.
Reading your response makes me believe you may not have a firm grasp of the first law of thermodynamics (conservation of energy) either. Look at it this way: You start with a pool of water. You end up with a pool of the same amount of water. There is no way to magically produce energy here.
To clarify what others have said about catalysts, I paraphrase the following line from the wikipedia link you posted:
"A catalyst is a substance which increases the rate of a chemical reaction but is not consumed in the reaction."
A catalyst increases the rate of the reaction, nothing more. How is does this is by lowering the activation energy required to start the reaction. The net energy cost or production is unaffected. A hypothetical example of this would be a reaction that required a welding torch to start could, with the addition of an appropriate catalyst, require only a pocket lighter to start. The amount of energy required or generated by the reaction would remain unchanged.
According to thermodynamics, some energy will be irretrievable between steps 1 and 2 in the real world. Thus, this reaction is not sustainable.
'Burn' ~ 'Combustion': You can't 'burn' oxygen, oxygen is an oxidation agent that you use to burn something else (a fuel). In this case, the fuel is hydrogen (ie your reaction #2).
Hypothetically, they would use some process to start it, and then feed back in as it goes.
but that they burn hydrogen somehow in a way that yields more energy than goes into extracting it from the most stable source of it, water.
So it's not claiming a closed system is self sustaining The first and second quotes are in direct contradiction of the third. Let's go over the basic equation that this car reportedly uses:
Water = H2O Oxygen = O2 Hydrogen = H
2 x H2O --(magic)--> 4 x H + O2 (4 x H) + O2 --(combustion)--> 2 x H20 + excess energy
Can you not see how this is an impossible self-contained system? You can't convert water to its component gasses and back, and expect to make an energy profit.
That's what scares me the most. People are using tools like truecrypt, yet unlike so many other tools that some terrorist might theoretically use, the US government does nothing. Perhaps there is something that they know about truecrypt that we dont.
You are forgetting something: Almost all usenet downloads take place from the NNTP server set up by the user's ISP. Each file is only transferred only once to each ISP via the Internet at large, rather than than once per user.
Also, you mischaracterised the the other side of the argument, too: a properly running torrent was many seed, and although each seed may have less uplink bandwidth than downlink bandwidth, the network as a whole should saturate the new peer's downstream bandwidth.
I totally agree with your post, except for the general sentiment of it, your implied conclusions, and almost every single point you tried to make.
I guess that means I didn't really agree with you much.
Well, why not take your best crossbows and your superior bows and fire them at your own LCD screens and compare your results? You can use any background color you like.
You may need someone to help you aim, as your vision might not be as good as you think, otherwise you may have noticed some other things in that video. Things like the part where the marker is removed from a part of the screen that was displaying white, not red. Or perhaps the part where the same bolts that were able to disable the screen penetrate a half-inch into a sheet of wood. Or perhaps the part where the screen is struck with a hammer.
According to you, this screen fared poorly as "the deep red background that the screen displayed, for example, will tend to hide scratches". Seriously, try these tests yourself. See if any color except black will hide the scratches on your monitors.
high level communication In animals? Really? From what I recall of my linguistics and psychology, language is reflexsive, arbitrary and symbolic. Which animals have this kind of communication?
On second thought, I regret posting in this thread, as some idiot will take it as invitation to post 'They had me up to "Posted by "kdawson"' or some other smarmy comment.
Come on, in classifying marijuana as a schedule I substance, they took the effect of the drug on society as a whole into account. It is the government's duty to do whatever it can to prevent another Cheech & Chong movie being made.
In this situation you would be the one implementing the DRM on your own house So, you build your own house from the ground up, brick by brick, rather than buying a house or hiring building contractors?
No, this is a troll. The submitter does not believe the story he submitted. He only submitted it to generate the attention from outraged slashdot readers about the post.
Slashdot Mirror
environmental footprint of a large solar farm is worse than that of an oil-rig or gas mine
The problem with both of those is they produce pollution both at the point of production and the point of consumption.
The idea of 'green' also hinges of 'renewable'. The supplies of coal, oil, gas and fissionable materials is severely limited, whereas the components needed for production of solar panels are significantly more plentiful.
I have made the correction. Check my reply to your post. The key phrase is "The net energy cost or production is unaffected."
The heat (energy) produced by burning the hydrogen cannot be sent back to help produce the hydrogen (work) with 100% efficiency. Some of the produced energy will be lost.
The idea you had is even more preposterous: Of course you can't move hydrogen from one point to another without using energy; causing anything to start moving costs energy. even if it is only hydrogen then its hydrogen from the air meaning you get (286KJ - inefficiency/mol) for every mol of starting water. What do you mean by 'from the air'? Extracting hydrogen from the atmosphere is not easy or cheap energy-wise, which is why they are bothering with the whole water-to-hydrogen malarkey to start with: it's one of the easiest ways to get hydrogen that they can then burn.
Your quoted number of 286KJ/mol: If that is the amount of energy produced by converting H and O2 into water, you need at least 286KJ/mol to convert water into H and O2 to start with.
Reading your response makes me believe you may not have a firm grasp of the first law of thermodynamics (conservation of energy) either. Look at it this way: You start with a pool of water. You end up with a pool of the same amount of water. There is no way to magically produce energy here.
To clarify what others have said about catalysts, I paraphrase the following line from the wikipedia link you posted:
"A catalyst is a substance which increases the rate of a chemical reaction but is not consumed in the reaction."
A catalyst increases the rate of the reaction, nothing more. How is does this is by lowering the activation energy required to start the reaction. The net energy cost or production is unaffected. A hypothetical example of this would be a reaction that required a welding torch to start could, with the addition of an appropriate catalyst, require only a pocket lighter to start. The amount of energy required or generated by the reaction would remain unchanged.
You should probably read the following:
http://en.wikipedia.org/wiki/Laws_of_thermodynamics
http://en.wikipedia.org/wiki/Combustion
According to thermodynamics, some energy will be irretrievable between steps 1 and 2 in the real world. Thus, this reaction is not sustainable.
'Burn' ~ 'Combustion': You can't 'burn' oxygen, oxygen is an oxidation agent that you use to burn something else (a fuel). In this case, the fuel is hydrogen (ie your reaction #2).
That's what scares me the most. People are using tools like truecrypt, yet unlike so many other tools that some terrorist might theoretically use, the US government does nothing. Perhaps there is something that they know about truecrypt that we dont.
Is that what you told the feds when they busted you for being a pedo?
Look, it's people like you what cause unrest.
You are forgetting something: Almost all usenet downloads take place from the NNTP server set up by the user's ISP. Each file is only transferred only once to each ISP via the Internet at large, rather than than once per user.
Also, you mischaracterised the the other side of the argument, too: a properly running torrent was many seed, and although each seed may have less uplink bandwidth than downlink bandwidth, the network as a whole should saturate the new peer's downstream bandwidth.
I totally agree with your post, except for the general sentiment of it, your implied conclusions, and almost every single point you tried to make.
I guess that means I didn't really agree with you much.
Well, why not take your best crossbows and your superior bows and fire them at your own LCD screens and compare your results? You can use any background color you like.
You may need someone to help you aim, as your vision might not be as good as you think, otherwise you may have noticed some other things in that video. Things like the part where the marker is removed from a part of the screen that was displaying white, not red. Or perhaps the part where the same bolts that were able to disable the screen penetrate a half-inch into a sheet of wood. Or perhaps the part where the screen is struck with a hammer.
According to you, this screen fared poorly as "the deep red background that the screen displayed, for example, will tend to hide scratches". Seriously, try these tests yourself. See if any color except black will hide the scratches on your monitors.
A guy I know recently started spamming these links all over the place. Turns out it is now the new 4chan fashion to play this game.
THIS JUST IN:
Scientists discover 'Peer Pressure'. Drinking, drugs, next?
The eraser still leaves evidence of the tampering behind, with a slight stain and the indentation on the paper.
On second thought, I regret posting in this thread, as some idiot will take it as invitation to post 'They had me up to "Posted by "kdawson"' or some other smarmy comment.
More smarmy than my first reply, I mean.
They had me up to "Assume that end users either always say 'Yes' or always say 'No' to security dialog boxes."
>>> get tea
you have:
tea
no tea
"The less able to talk the android is, the better" say experts.
Who calls USB memory sticks 'USB Keys'?
Come on, in classifying marijuana as a schedule I substance, they took the effect of the drug on society as a whole into account. It is the government's duty to do whatever it can to prevent another Cheech & Chong movie being made.
This was modded insightful? I think Slashdot mods have expectations that are a little low...
No, this is a troll. The submitter does not believe the story he submitted. He only submitted it to generate the attention from outraged slashdot readers about the post.
You could even say it's old hat.