You said: "Not true. Check out the faq on the British Wind Energy Association page - in practice, on a large grid, the "averaging" process means that variability in wind-power is much less of a problem than originally envisaged - the wind is always blowing somewhere, and there are sites with pretty constant, strong winds. It is also a myth that other sources are "reliable" - outages from traditional Coal/Gas/Nuclear plants (or the power lines to them) are common, and have to be catered for. In reality keeping a "stable" grid is a complex balancing act - keeping a minimum spinning reserve for possible outages."
First let me show you the calculations that show that the power per unit area of an ideal wind generator is proportional the cube of the wind speed: The kinetic energy of a particle in 'wind' is 1/2 the mass of the particle times its velocity squared. Therefore, the kinetic energy per unit volume is 1/2 the density times the velocity squared. The rate of flow of air through a column of cross sectional area A (the wind generator) is the area times the speed of the wind. Therefore the power that can be extracted if the wind can be brought to a halt is 1/2 the density times the area times the velocity cubed (since the wind must have some residual speed the ideal genrator is about 60% of this value). This shows that the power generated is proportional to the velocity of the wind. From here it is easy to show that small drops in wind speed have significant effects on power output.
Second, wind is a regional event. Taking into consideration the I^2*R losses that I previously discussed, there may be times that it is uneconomical to send power to a region that has lower than normal wind flow. As the FAQ that you referenced points out:
When the wind stops blowing, electricity continues to be provided by other forms of generation, such as gas etc. Our electricity system is mostly made up of large power stations, and the system has to be able to cope if one of these large plants goes out of action. It is possible to have up to 10% of the country's needs met by intermittent energy sources such as wind energy, without having to make any significant changes to the way the system operates. More can be accommodated, but extra storage capacity or spinning reserve would be necessary, which would have a cost implication.
It seems to me that even without the I^2*R losses preventing extensive long-range power distribution , if all the electric grids power were produced by wind, using your avereraging idea, that there would always be some probability that, due to some weather situation, the grid could not supply all the power needs unless there were built in significant reserve wind turbine plants whose only purpose would be to come online to backup lower power generating plants. This would be very ineconomical, and the alternative of a brownout is distasteful.
Lastly, I would like to point out that outages for coal and nuclear plants are typically scheduled months in advance. This allows agreements to be made on which plants have to be operational to supply full power to the grid. Wind stations can have an effective outage in hours as wind speed drops. This allows no time for careful planning to maintain full power to the grid.
You said: "They're called "batteries". People are already living off-the-grid with photovoltaic, wind, or a combination, as their only electric source."
Unfortunately, you have completely missed my point. Are you seriously suggesting that a battery farm can be developed that can support the capacity of an electric power plant? Are you also suggesting that this would be economical? I understand that some people are living off the grid. This is easy when your home uses only 2 KW of electricity. A 50 A-hr 12V car battery, for example, has about 2160000 Joules of energy. With a 2KW load (typical for most houses), this will last for a total of 18 minutes of power. So if you want to operate at a 2 KW load for 8 hours (until the sun comes up for example), you need 20 car batteries! Now the question is, do the people who live off the grid still drive to work with gasoline fueled cars? A typical car uses over 100 KW of power. For a 30 minute trip at 50 KW (not full power), you would need almost 42 batteries to get there! As your car uses significantly more power than your house when operating, so does industry compared to residential. If you need 20 car batteries to power your house at night, a 40 MW silicon refining plant outside my hometown would need to use 40,000 car batteries! To me, this is even beyond reason. Taking into account battery lifetimes, charge and discharge efficiencies, etc., I am flabbergasted. Please tell me that I am confused at your suggestion.
You said: "The problem is that given where most of the excess energy comes from (coal, natural gas) it actually is more efficient in a net-energy sense to build a powerplant within a few miles of the coal mine/gas gathering system, and ship the electricity via transmission lines than it is to truck the coal or LNG to a powerplant all the way Southern California."
Not generally true. I^2*R losses in distribution lines seriously limit the ability to send power over long distances. For this reason there is an optimal balance between distribution line length and coal transportation length. This is why Montana having the most coal in the country is not a very rich state and at the same time New York state couldn't help California during its energy crisis (other than the technical grid difficulties).
You said: "My own 2c (per kw/hour) is that the very simple obvious non-polluting green alternatives - wind, tide, wave, solar, etc - have quietly evolved to a stage where they could take over as the western worlds main source of energy. Why do we need to mess around with nuclear/coal/oil? All the supporting technologies have developed sufficiently that they are either already economical, or at worse should be soon with a little more work. If you just take wind alone, the latest batch of offshore wind farms are contracted to supply power to the UK grid at 0.03 pounds/kilowatt/hour - pretty competitive, and set to come down with scale."
Calculations can show that an ideal (no friction in parts) wind generator has a power to surface area ratio equal to 8/27 of the density of air times the cube of the wind velocity. This means that a 20% reduction is the wind velocity will lead to roughly a 50% reduction in power output from a given wind plant. For this reason alone it should be obvious that wind plants are only useful for reducing the load of other plants (as long as they can come back up to full capacity or have peaking plants standing by). By no means can wind be only energy generator for an area.
Other weather issues hamper solar generation. For example, what do you do when the day is cloudy and your solar cells are not putting out as much output (or night). Again, unless you have some massive means of energy storage, solar power cannot be the only energy generator for an area.
Tide? Neat idea. I'd like to see it developed further. But its not going to help someone power their toaster in Chicago, Illinois.
Some of the key points that people miss when they talk about power generation: 1. I^2*R losses make it ineconomical to send electricity over long distances. This means that power plants need to be near where the power is being used (even nuclear) and that interstate electricity sales only work for adjacent states. Many people look at the numbers and say "We need another 1 GW of additional electrical generating capacity. Lets put a large plant in Montana and send it to where we need it." It doesn't work that way. Electrical providers spike up the voltage as much as they can on distribution lines to minimize losses but there is a practical limit. On a side note, if room temperature superconductors are ever produced we should see a drastic change is location of production, trade, and distance from power plants. 2. Many electrical plants are designed to operate the most efficiently or economically at 100% load. Like airlines, if the plane is not flying with as many passengers as possible (so to speak), you are not maximizing your profit. There are serious overhead costs for any power plant. Nuclear plants, in particular, need to be making as much power as possible to remain profitable (as fuel for nuclear plants is almost a negligable cost). What this means is that if you have alternative technologies taking load off of larger plants, but still wish to have the reserve load (unused load in the larger plants) if your alternative technologies go offline, it will cost you more money that with just the larger plants. This is because you are effectively paying for both the large plant and your alternative technologies at the same time and the cost will be very close regardless of how the load is distributed (since the overhead costs are the most significant costs).
You said: "That's under simulated conditions. This is not a study saying, "OMFG TEH USIANS ARE TEH PULLUT3RZ! THEY R KILING TEH PLANET!!!!!1111" It describes what could happen were CO2 concentrations in the atmosphere to increase by 1% annually. I don't know whether this is actually the current trend. I'd also like to point out that carbon dioxide emissions should not be confused with traditional pollutants, such as carbon monoxide (CO) and surphur dioxide (SO2). The irony is that continued advances in catalyst technology used in ULEV vehicles is eliminating these poisons, only to produce more water and, you guessed it, carbon dioxide. Of course, the answer is to increase efficiency of internal combustion engines until they can be eliminated by a more efficient technology"
In these two conflictingreports, the CO2 concentrations is shown to increase from about 310 ppm to 360 ppm from year 1960 to 2000. About a 0.4% increase per year. Of course the rate of increase is increasing so the current value is higher than 0.4% increase per year; therefore, the 1% increase per year figure is certainly possible. The two reports cited are but an example of several reports trying to understand the connection of CO2 to future surface temperatures. I think you will have to take all these reports into mind before coming to a conclusion on whether the current trend of CO2 increase will affect hurricanes.
I think its pretty obvious from most studies that rapid deforestation, massive livestock populations, and industrialization have pretty much been the cause of the CO2 and methane increases over the past 200 years. If there is a connection between our pollutants and global temperatures and events like hurricanes or if it is sufficiently probable then it is logical to impose some kinds of restrictions on the above mentioned pollutant emissions. Currently, there are no absolutely conclusive reports one way or the other so it is a view of opinion which studies you agree are more probable in being correct. I tend to agree with the global warming hypothesis but I am still going to monitor the other literature to see if it will change my opinion.
You said "Even the most complicated computer models for weather systems can only approach less than 5% of the actual variability and density of the atmosphere. Consider that most forecasts are less than 50% accurate at 48hrs+. I am not dismissing the research, far from it, I just don't think the models are there yet."
The key point is that they are less than 50% accurate for short term forcasts. The same rule applies to psychology for diagnosing a single patient (meaning that it isn't always particularly effective).
This rule does not apply for large sums. Psychology, for example, is an extremely predictable science for sample sizes greater than 1000 or so. The same will apply to weather forcasts. And it makes complete sense since hurricanes are fueled by thermal energy. Increasing the overall thermal energy of the planet can only make them more probable.
Of course predicting when one will occur is very difficult.
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· Score: 1
You said: "Amen. 99% of anti-nuclear activists don't have a clue what they're talking about."
I'm not a anti-nuclear activist. In fact, you would probably say the opposite about me, but I am very suprised by the activities listed in the article. A simple thumb rule in radiation studies is that a 1 Curie point source at 1 meter gives a dose rate of 1 rem/hr. For point sources, the levels will follow an inverse square law. For a 1 milli-Curie source listed in the article a *significant* dose could be recieved if ingested. If you assume that the thumb rule holds for nickel-63, everything in 25 micrometers would receive a dose rate of 1.6 million rem/hr. Obviously the thumb rule has to break down (because at 0 meters the dose is infinite), but a significant dose will still be received at the penetration distance nonetheless. Most people in the nuclear industry are worried about hundreds of pico-Curie sources, and the ones listed in the article are fairly large (but obviously tiny compared to spent fuel).
Re:Unknown Error In The Submission
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Nuclear Batteries
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· Score: 4, Informative
You said: " The layer of dead skin blocks it outright. The radiation can only travel 25 micrometers through most liquids."
This is correct, but misleading. An alpha particle (a helium nucleus) has a charge of +2e. This makes it difficult to travel through dense matter as it will quickly loose its kinetic energy (typically about 5 MeV range--normal matter on Earth has about 0.025 eV) by being scattered by electrons in the absorbing material (note that chargeless particles like neutrons or neutrinos have very large ranges in matter). Therefore, it's energy will be dispersed throughout the matter that slowed it down. For living cells this amount of energy is enough to kill the cell or cause some reaction that will cause the cell to mutate (where it may survive on mitosis or die). Obviously this is not a concern for dead cells.
If the alpha emitter is volatile or made into a dust, it can be inhaled. In this case, your respiratory system is affected. Additionally if it is ingested, your gastrointestinal system is affected. So obviously the greatest concern in the design of this battery is how its containment prevents it from being released. Logically if the alpha particle can't penetrate your dead skin cells, it won't penetrate a thin containment shield. If the containment breaks down and particles are easily disolved in water or break up and become dust easy, there is more concern about the safety of this device.
You said: "WTF are you talking about ? This is dense plasma physics, at these energies the only quantum effects are atomic, QED, and, hopefully, nuclear-fusion physics: the first principles for all are rather well understood."
The first principle for quantum mechanics, the wave equation is not well understood. Its not an obvious axiom like those of Euclid. We are still learning new things from it by interpreting it (similar to the way Einstein had to interpret Newton's concept of inertia to develop special relativity).
Additionally the characterization of the strong nuclear force is not well known. Quantum chromodynamics (the nuclear force spin-off of quantum electrodynamics) is so computationally exhaustive that it still sits in the area of physics that string theory does: inconclusive but promising.
And finally the characterization of plasma temperature, density required, and time to hold to cause fusion is not well known. This is an area of intense research where alot of unknown effects are still being investigated.
Tthe rotation of the Galaxies doesn't follow Kepler's Laws of planetary motion (which should apply if you consider all the stars in the galaxy to be planets). The easiest way to look at this is to compare the rotational velocities of the stars in the galaxy (which can be determined by taking the red/blue shift of the galaxy in general to determine its velocity relative to you and then taking the redshift of stars in the galaxy that are roughly parallel to your line of sight). Kepler's Third Law says that the orbital period squared is proportional to the long elliptical axis of the orbit cubed. Stars in galaxies don't do this so it is supposed that there is a dark matter halo surrounding the galaxy that corrects their motion to what is observed (of roughly ten time the mass of the galaxy). It is called dark matter because it can't be seen through electromagnetic radiation.
You said: "No, you don't. This might be true if you were trying to gently land on the sun. To get to the sun, you just have to alter the trajectory a bit. It can be traveling a million km/s when it hits the sun. It won't matter."
No, this is a common fallacy. If I point my rocket towards the Sun and fire, i go into an elliptical orbit. If I fire my rockets in the direction that the Earth is travelling, I go into a slightly higher orbit. If I fire my rockets opposite of the earths motion I go into a slightly lower orbit--this is the least energy solution.
You said: "Nuclear power really is very safe and controlled - the only reason Chernobyl happened at all was that some idiot had the bright idea to turn off the control system, and then turn off the back-up control system. Other than that and 3 Mile Island (which was a remarkably similar, easily avoidable situation),"
Chernobyl happened for the following reasons: 1. The Soviet government wanted to perform a test on the reactor's turbines. 2. The Soviet testers took control of the reactor (not directly--they just gave orders to the operators). The operators, whose job was reactor safety and who knew the reactor the best were no longer in charge or reactor safety. Now the test scientists who knew their test very well but not the reactor plant were in charge of the reactor. 3. The safeguards on the reactor were *intentionally* shut down in order to operate the reactor *intentionally* in an unsafe way (at low power). 4. The testers rushed the test because of schedule concerns. 5. The reactor was operated for full power during the day contrary to the testing schedule. Additionally the test was performed late at night when most of the reactor plant managers and supervisors (who would normally watch the tests like a hawk) were gone. 6. And the least significant factor, but the one that allowed the reactor to blow up: reactor design (power increases as water boils and a shutdown in the unsafe condition that the testers put it in would cause a brief power spike--coupled together it blew up the core).
Three Mile island was significantly different. In brief, it was caused by improper maintenance, improper value lineups on reactor safety systems, material failures, an incredibly overcomplicated reactor control and indication system, operators not believing their indications, and improper operator training and operation.
I'm not against nuclear power at all (I work as a reactor operator), but both of these accidents were mostly due to political reasons. In Chernobyl, the Soviet government did not have adequate respect for reactor safety and rushed a test. In TMI, the NRC (which IMHO had previously downplayed reactor incidents) did not regulate enough the maintenance and operation aspects of the reactor (and in particular the operator training). I think both of these problems have been fixed, but careful attention must be directed at all nuclear plants to not repeat these accidents.
You said: "The bigger problem with nuclear power is getting rid of the waste products. If someone could figure out a good way to launch those into the sun cheaply nuclear power would probably be the best solution"
The waste problem is completely political. If it wasn't for cold war/war on terrorism fears (no reprocessing of waste or use of breeder reactors) and irrational fears of storage (not in my backyard syndrome), waste could be safely reprocessed and the minimal high level waste could be safely stowed away.
I hope you didn't underestimate the difficulty on getting anything to the sun. The Earth's orbital speed is about 30 km/s. Kinetic energy is one-half the mass times the velocity squared. In order to get to the sun you have to cancel out the 30 km/s orbital speed (where 0 km/s is the Sun's 'orbit') and that will require enourmous amounts of energy. Doesn't really make sense.
During November 2002--July 2003, a total of 8,098 probable SARS cases were reported to the World Health Organization (WHO) from 29 countries, including 29 cases from the United States; 774 SARS-related deaths (case-fatality rate: 9.6%) were reported
Additionally the mortality rate of SARS varies based on age, where the WHO, for example, have estimated a mortality rate of greater than 50% for people over the age of 65. I don't really see why you think its ironic at all that so much effort is being put into a disease that is so dangerous (particularly to our elderly).
the display reorientates on each use and is inactive after being used. This prevents a person from guessing that a person pressed '1' because he pressed the upper left key, and it prevents an infrared camera from doing the same based on the heat left on a pressed key.
The problem can be solved easy enough with a numeric keypad. Place seven-segment displays under the keys that are randomly orientated, like 7 5 2 4 3 1 0 9 6
8 This solves the problem for ATMs. If you dim the LEDs and polarize the light, you would make it more difficult for a camera to find the password also. Obviously this only applies to a numeric keypad (for ATMs and the like) since it would be a pain in the ass to change the lettering dynamically on a keyboard (at least for the user). The solutions for those using keyboards could be as simple as using a smartcard with a PIN number (which you enter on the randomized 10 digit display). The sooner we get rid of the biggest security risk on computers IMHO (guessable passwords) the better.
You said: "You are not creating energy, since the mass in energy in itself, it is what there's no law of convervation of mass, you just need the law of conservation of energy, since mass is energy...
Sorry that I got to nitpick your nitpick:
Mass and energy are both human terms. They have no inherent meaning beyond how we interpret them. But one of our interpretations is that energy can do work. Now its fairly obvious that mass can be converted to energy and then do the work, but my point is, as far as interpreting as a linguist (which I am certainly not), mass and energy are certainly different. Now you can say mass is energy and energy is mass as long as you want but you have to be careful that you don't lose your meaning when you do so. For example, I can easily say that an electron has a mass of about 0.5 MeV, but I certainly wouldn't measure the mass of an apple in Joules.
You said: "Making energy would defeat Law of Conservation of Energy (and most likely Law of Conservation of Mass, since that's how most of the energy we're accustom to seeing is expressed). IANAP, but it really does get irritating to see this in writing... I guess you could reform it as: Any technology can be used for good or evil, especially technology that deals with releasing or storing energy."
Actually, my job does create energy (I work as a reactor operator). I just decrease mass by doing it.
You said: "the fact is that plutonium can only be used for weapons, period."
A quick lesson in nuclear physics:
A nuclear reactor operates by fissioning a fissible fuel (no suprise here!). While I'm not going to describe the physics of criticality you can look it up elsewhere. A fissible fuel is a fuel that will fission when hit by an alpha or a neutron. Due to the physics of criticality, alphas are not used (they have too short of a range and are rarely released from fission fragments anyways). Neutrons are used in two forms: fast and slow. A nuclear weapon will use fast neutrons (neutrons that after whatever reaction that created them have not been moderated) and a nuclear reactor will use slow neutrons (neutrons that have slowed down to the ambient kinetic energy of the reactor--typically by water or graphite).
It should be fairly obvious why only very heavy elements are used in fissible fuel. But due to a quirk in physics, only the odd atomic mass fuels work well. This is due to the fact that in order to cause fission you have to agitate the nucleus enough for it to split. Typically this is about 5 MeV of kinetic energy for an even numbered fuel. For an odd numbered fuel, the internal nuclear reaarangement gives this amount of energy so that a nucleus can fission with a slow neutron while an even numbered fuel needs a fast neutron with a very high kinetic energy.
What does this mean? U-233 is a slightly worse fuel than U-235 which will be a slightly worse fuel than Pu-239. Since Pu-239 is heavier than U-235 (which is used in an enriched form in nuclear reactors) it will be more suitable for nuclear reactors.
What about those fast neutrons, will they work? Yes, but common sense says that if they are slowed down they will have more interactions before escaping from a reactor, so they would work better. Nuclear bombs don't have the time for neutrons to slow down to ambient before interactions so they depend entirely on fast neutrons (the converse shows why a nuclear reactor can never explode like a nuclear bomb).
Any technology can be used for good or evil, especially technology that makes energy. Alfred Nobel, the inventor of TNT, knew this only too well. He created the Nobel prize so people wouldn't remember him as the creator of a weapon.
As far as understanding what technology's consequences are: technology is part of society. Its not that somehow society and technology can be seperated and analyzed so that only the 'good' technology can interface somehow with society. Society is what causes the technology to exist in the first place and continue its development. Society has as much as an effect on the dangers of the technology as the mechanics of the technology itself.
Some may argue that technology can't be released until its full impact on society is known. Thats impossible, as a modern technological society can't exist as a free state with blantant censorship. These issues aren't suddenly new. Its the same problem that engineers throughout history have had to deal with when they realized that their peaceful invention could have dangerous implementations. Research DNA, make more powerful bioweapons. Reasearch nuclear power, make the most powerful WMDs. Research network technology, make the powerful network warfare that we saw in the beginning of Gulf War 2.
Correct the society and the consequences of the technology will follow along.
I've said this before and I'll say it again: personal attacks do not win arguments, they are only intended to confuse the facts. Only the truth wins arguments, and it doesn't matter who says it (it could be a trashman or Niels Bohr himself who says it, it doesn't matter). Additionally, its generally not a very good idea to make generalizations or try to draw conclusions from the behavior of a person you have never met. Chances are your conclusions are off. Now to get to my point.
You said: "But it is possible to play a character motivated by a need to win battles, and for that character, optimizing combat effectiveness isn't munchkinism, it's exactly what their character would do."
And previously: "Some of us want to play the role of a master of fighting prowess. who puts evil abominations to the sword."
I think you missed my point on the halberd. Its not a general purpose fighting weapon. Its meant to be a can opener for heavy armor. How exactly is using it on the field a good idea? If you would put yourself into that role I think you would understand that in general field usage you would get killed very quickly. If you put yourself into the role of a master of fighting prowess, for example, I would expect you to more likely pick a weapon that is more general purpose.
Now let me phrase my point on the halberd: a role player is a person who picks it as a weapon because he or she intends to attack heavy armor and it is the logical weapon. A powergamer picks it because a simplistic game world gives it more points of damage while not giving the significant detraction that a person using it would have basically no defensive ability in one on one combat.
This reminds me of an old problem that existed in Ultima Online. At one point the halberd was the best weapon for a fighter. Now if people were actually roleplaying they would probably pick weapons more suited to different fighting roles than the halberd which is a fairly exotic military weapon. You could probably expect some people to play knights using swords as their weapons, others as archers, etc. But did this happen? No of course not, everyone picked the halberd. Later when a game patch came out that made the kitana the most powerful weapon, did those people stay with the halberd? Nope. They jumped ship for statistical reasons.
How is this roleplaying? How is knowing that your weapon will deal 2 points more of damage a turn on average versus a competitor the deciding factor for someone who wants to play a role as a knight (as an example)?
Its powergaming, not roleplaying. Roleplaying is taking all the good and the bad of a character and making due with it. When you powergame, there is no role being explored; it more like fun with statistics.
You said: " Problem is that D&D's number-crunching sucks and instead of focusing on giving the player a thousand numbers to concern himself with, it'd be better to make a fun game."
Thats why the White Wolf games are so lax on numbers and vague on what some attribute to your ability will do. The point of a RPG is to role play, not to kill monsters and powergame. Unfortunately, most of the public thinks the latter is what an RPG is. It is painstakingly difficult to talk about a pen and paper RPG without others thinking your are a D&D powergaming freak. Its sad really, since RPGs are a great intellectual game. Once anyone focuses more on making the RPG compliant so that the numbers balance out, they've lost the point of the game altogether.
You said: "Here's the thing you see, there are a million and one ways we can all use less electricity and keep every gadget we run and more, here's some examples: monitors,...lightbulbs,...appliances,...trash,... heating"
How about we focus on the areas where power saving is the most. An average home uses about 2 KW of power. More if you use electric heating. The greatest uses are: (1) Heating (>1KW while cycling) (2) A/C (>1KW while cycling) (3) Washer & dryer (~1KW) (4) Stove (~1KW) (5) Microwave (~0.7 KW) (6) Refrigerator (~1KW when the compressor is running) (7) Misc entertainment (Tv's, etc) (~0.5 KW)
The first 2 use the most power by far. Properly insulate your house and you dramatically cut down on energy consumption. The third can be cut down by making sure your washer and dryer are full when operating (fewer times they are operated). Twist out the excess water (or use a closeline) from washing and you will significantly cut down on the dry time. The fourth can be cut down if you use a toaster oven for small meals. No reason heating up so much metal just to cook a TV dinner. The fifth through seventh can be cut down by using energy efficient models.
Now here's my point: Lets not focus on replacing lightbulbs when your house is radiating 500 W of heat! Focus on big things!
You also said: "I really wouldn't expect an American to understand this."
This elitest attitude is totally unfounded! I can't believe you thought it appropriate at all to make this statement. This is nothing more than a personal attack directed at each American reading this board. But even though you have this elitest attitude, I will try to educate you on one thing: personal attacks never win arguments. They are only made to confuse the argument. There is only one thing that can win an argument: the truth. It doesn't matter if the truth is said by Neils Bohr, and American, or a trashman: the truth is all that can settle an argument. No more personal attacks please, it makes you look foolish.
You said: " Why is it that we have this never ending need for more powerlines and more electricity rather than looking for alternatives with any real conviction?"
The reason is because most of the power generated is used by industry, not by houses. I used to live in a town of 30,000 that used 30 MW of power for residential areas. Just one plant outside my town used 60 MW of power. If you conserve power, use alternative energy, etc., it will do nothing to curb the growth of energy use. Industry survives by growing. To give you another example, the town that I was just talking about used to have a population of 100,000 where 30,000 were miners. Now it has less than 500 miners and they pull more minerals out of the ground now than they did with 30,000! Obviously there are tons on industries that could tell the same stories, because machines (which run on electricity, not magic) and increased automation have replaced the need for people. And industry will continue to build bigger and use more power. The only way that you can stabilize and lower energy usage is by enacting laws that prevent industry to grow! Of course, I would love to see the debate in Congress over that one.
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First let me show you the calculations that show that the power per unit area of an ideal wind generator is proportional the cube of the wind speed: The kinetic energy of a particle in 'wind' is 1/2 the mass of the particle times its velocity squared. Therefore, the kinetic energy per unit volume is 1/2 the density times the velocity squared. The rate of flow of air through a column of cross sectional area A (the wind generator) is the area times the speed of the wind. Therefore the power that can be extracted if the wind can be brought to a halt is 1/2 the density times the area times the velocity cubed (since the wind must have some residual speed the ideal genrator is about 60% of this value). This shows that the power generated is proportional to the velocity of the wind. From here it is easy to show that small drops in wind speed have significant effects on power output.
Second, wind is a regional event. Taking into consideration the I^2*R losses that I previously discussed, there may be times that it is uneconomical to send power to a region that has lower than normal wind flow. As the FAQ that you referenced points out:It seems to me that even without the I^2*R losses preventing extensive long-range power distribution , if all the electric grids power were produced by wind, using your avereraging idea, that there would always be some probability that, due to some weather situation, the grid could not supply all the power needs unless there were built in significant reserve wind turbine plants whose only purpose would be to come online to backup lower power generating plants. This would be very ineconomical, and the alternative of a brownout is distasteful.
Lastly, I would like to point out that outages for coal and nuclear plants are typically scheduled months in advance. This allows agreements to be made on which plants have to be operational to supply full power to the grid. Wind stations can have an effective outage in hours as wind speed drops. This allows no time for careful planning to maintain full power to the grid.
You said: "They're called "batteries". People are already living off-the-grid with photovoltaic, wind, or a combination, as their only electric source."
Unfortunately, you have completely missed my point. Are you seriously suggesting that a battery farm can be developed that can support the capacity of an electric power plant? Are you also suggesting that this would be economical? I understand that some people are living off the grid. This is easy when your home uses only 2 KW of electricity. A 50 A-hr 12V car battery, for example, has about 2160000 Joules of energy. With a 2KW load (typical for most houses), this will last for a total of 18 minutes of power. So if you want to operate at a 2 KW load for 8 hours (until the sun comes up for example), you need 20 car batteries! Now the question is, do the people who live off the grid still drive to work with gasoline fueled cars? A typical car uses over 100 KW of power. For a 30 minute trip at 50 KW (not full power), you would need almost 42 batteries to get there! As your car uses significantly more power than your house when operating, so does industry compared to residential. If you need 20 car batteries to power your house at night, a 40 MW silicon refining plant outside my hometown would need to use 40,000 car batteries! To me, this is even beyond reason. Taking into account battery lifetimes, charge and discharge efficiencies, etc., I am flabbergasted. Please tell me that I am confused at your suggestion.
You said: "The problem is that given where most of the excess energy comes from (coal, natural gas) it actually is more efficient in a net-energy sense to build a powerplant within a few miles of the coal mine/gas gathering system, and ship the electricity via transmission lines than it is to truck the coal or LNG to a powerplant all the way Southern California."
Not generally true. I^2*R losses in distribution lines seriously limit the ability to send power over long distances. For this reason there is an optimal balance between distribution line length and coal transportation length. This is why Montana having the most coal in the country is not a very rich state and at the same time New York state couldn't help California during its energy crisis (other than the technical grid difficulties).
You said: "My own 2c (per kw/hour) is that the very simple obvious non-polluting green alternatives - wind, tide, wave, solar, etc - have quietly evolved to a stage where they could take over as the western worlds main source of energy. Why do we need to mess around with nuclear/coal/oil? All the supporting technologies have developed sufficiently that they are either already economical, or at worse should be soon with a little more work. If you just take wind alone, the latest batch of offshore wind farms are contracted to supply power to the UK grid at 0.03 pounds/kilowatt/hour - pretty competitive, and set to come down with scale."
Calculations can show that an ideal (no friction in parts) wind generator has a power to surface area ratio equal to 8/27 of the density of air times the cube of the wind velocity. This means that a 20% reduction is the wind velocity will lead to roughly a 50% reduction in power output from a given wind plant. For this reason alone it should be obvious that wind plants are only useful for reducing the load of other plants (as long as they can come back up to full capacity or have peaking plants standing by). By no means can wind be only energy generator for an area.
Other weather issues hamper solar generation. For example, what do you do when the day is cloudy and your solar cells are not putting out as much output (or night). Again, unless you have some massive means of energy storage, solar power cannot be the only energy generator for an area.
Tide? Neat idea. I'd like to see it developed further. But its not going to help someone power their toaster in Chicago, Illinois.
Some of the key points that people miss when they talk about power generation:
1. I^2*R losses make it ineconomical to send electricity over long distances. This means that power plants need to be near where the power is being used (even nuclear) and that interstate electricity sales only work for adjacent states. Many people look at the numbers and say "We need another 1 GW of additional electrical generating capacity. Lets put a large plant in Montana and send it to where we need it." It doesn't work that way. Electrical providers spike up the voltage as much as they can on distribution lines to minimize losses but there is a practical limit. On a side note, if room temperature superconductors are ever produced we should see a drastic change is location of production, trade, and distance from power plants.
2. Many electrical plants are designed to operate the most efficiently or economically at 100% load. Like airlines, if the plane is not flying with as many passengers as possible (so to speak), you are not maximizing your profit. There are serious overhead costs for any power plant. Nuclear plants, in particular, need to be making as much power as possible to remain profitable (as fuel for nuclear plants is almost a negligable cost). What this means is that if you have alternative technologies taking load off of larger plants, but still wish to have the reserve load (unused load in the larger plants) if your alternative technologies go offline, it will cost you more money that with just the larger plants. This is because you are effectively paying for both the large plant and your alternative technologies at the same time and the cost will be very close regardless of how the load is distributed (since the overhead costs are the most significant costs).
You said: "That's under simulated conditions. This is not a study saying, "OMFG TEH USIANS ARE TEH PULLUT3RZ! THEY R KILING TEH PLANET!!!!!1111" It describes what could happen were CO2 concentrations in the atmosphere to increase by 1% annually. I don't know whether this is actually the current trend.
I'd also like to point out that carbon dioxide emissions should not be confused with traditional pollutants, such as carbon monoxide (CO) and surphur dioxide (SO2). The irony is that continued advances in catalyst technology used in ULEV vehicles is eliminating these poisons, only to produce more water and, you guessed it, carbon dioxide. Of course, the answer is to increase efficiency of internal combustion engines until they can be eliminated by a more efficient technology"
In these two conflicting reports, the CO2 concentrations is shown to increase from about 310 ppm to 360 ppm from year 1960 to 2000. About a 0.4% increase per year. Of course the rate of increase is increasing so the current value is higher than 0.4% increase per year; therefore, the 1% increase per year figure is certainly possible. The two reports cited are but an example of several reports trying to understand the connection of CO2 to future surface temperatures. I think you will have to take all these reports into mind before coming to a conclusion on whether the current trend of CO2 increase will affect hurricanes.
I think its pretty obvious from most studies that rapid deforestation, massive livestock populations, and industrialization have pretty much been the cause of the CO2 and methane increases over the past 200 years. If there is a connection between our pollutants and global temperatures and events like hurricanes or if it is sufficiently probable then it is logical to impose some kinds of restrictions on the above mentioned pollutant emissions. Currently, there are no absolutely conclusive reports one way or the other so it is a view of opinion which studies you agree are more probable in being correct. I tend to agree with the global warming hypothesis but I am still going to monitor the other literature to see if it will change my opinion.
You said "Even the most complicated computer models for weather systems can only approach less than 5% of the actual variability and density of the atmosphere. Consider that most forecasts are less than 50% accurate at 48hrs+. I am not dismissing the research, far from it, I just don't think the models are there yet."
The key point is that they are less than 50% accurate for short term forcasts. The same rule applies to psychology for diagnosing a single patient (meaning that it isn't always particularly effective).
This rule does not apply for large sums. Psychology, for example, is an extremely predictable science for sample sizes greater than 1000 or so. The same will apply to weather forcasts. And it makes complete sense since hurricanes are fueled by thermal energy. Increasing the overall thermal energy of the planet can only make them more probable.
Of course predicting when one will occur is very difficult.
You said: "Amen. 99% of anti-nuclear activists don't have a clue what they're talking about."
I'm not a anti-nuclear activist. In fact, you would probably say the opposite about me, but I am very suprised by the activities listed in the article. A simple thumb rule in radiation studies is that a 1 Curie point source at 1 meter gives a dose rate of 1 rem/hr. For point sources, the levels will follow an inverse square law. For a 1 milli-Curie source listed in the article a *significant* dose could be recieved if ingested. If you assume that the thumb rule holds for nickel-63, everything in 25 micrometers would receive a dose rate of 1.6 million rem/hr. Obviously the thumb rule has to break down (because at 0 meters the dose is infinite), but a significant dose will still be received at the penetration distance nonetheless. Most people in the nuclear industry are worried about hundreds of pico-Curie sources, and the ones listed in the article are fairly large (but obviously tiny compared to spent fuel).
You said: " The layer of dead skin blocks it outright. The radiation can only travel 25 micrometers through most liquids."
This is correct, but misleading. An alpha particle (a helium nucleus) has a charge of +2e. This makes it difficult to travel through dense matter as it will quickly loose its kinetic energy (typically about 5 MeV range--normal matter on Earth has about 0.025 eV) by being scattered by electrons in the absorbing material (note that chargeless particles like neutrons or neutrinos have very large ranges in matter). Therefore, it's energy will be dispersed throughout the matter that slowed it down. For living cells this amount of energy is enough to kill the cell or cause some reaction that will cause the cell to mutate (where it may survive on mitosis or die). Obviously this is not a concern for dead cells.
If the alpha emitter is volatile or made into a dust, it can be inhaled. In this case, your respiratory system is affected. Additionally if it is ingested, your gastrointestinal system is affected. So obviously the greatest concern in the design of this battery is how its containment prevents it from being released. Logically if the alpha particle can't penetrate your dead skin cells, it won't penetrate a thin containment shield. If the containment breaks down and particles are easily disolved in water or break up and become dust easy, there is more concern about the safety of this device.
You said: "WTF are you talking about ? This is dense plasma physics, at these energies the only quantum effects are atomic, QED, and, hopefully, nuclear-fusion physics: the first principles for all are rather well understood."
The first principle for quantum mechanics, the wave equation is not well understood. Its not an obvious axiom like those of Euclid. We are still learning new things from it by interpreting it (similar to the way Einstein had to interpret Newton's concept of inertia to develop special relativity).
Additionally the characterization of the strong nuclear force is not well known. Quantum chromodynamics (the nuclear force spin-off of quantum electrodynamics) is so computationally exhaustive that it still sits in the area of physics that string theory does: inconclusive but promising.
And finally the characterization of plasma temperature, density required, and time to hold to cause fusion is not well known. This is an area of intense research where alot of unknown effects are still being investigated.
Tthe rotation of the Galaxies doesn't follow Kepler's Laws of planetary motion (which should apply if you consider all the stars in the galaxy to be planets). The easiest way to look at this is to compare the rotational velocities of the stars in the galaxy (which can be determined by taking the red/blue shift of the galaxy in general to determine its velocity relative to you and then taking the redshift of stars in the galaxy that are roughly parallel to your line of sight). Kepler's Third Law says that the orbital period squared is proportional to the long elliptical axis of the orbit cubed. Stars in galaxies don't do this so it is supposed that there is a dark matter halo surrounding the galaxy that corrects their motion to what is observed (of roughly ten time the mass of the galaxy). It is called dark matter because it can't be seen through electromagnetic radiation.
You said: "No, you don't. This might be true if you were trying to gently land on the sun. To get to the sun, you just have to alter the trajectory a bit. It can be traveling a million km/s when it hits the sun. It won't matter."
No, this is a common fallacy. If I point my rocket towards the Sun and fire, i go into an elliptical orbit. If I fire my rockets in the direction that the Earth is travelling, I go into a slightly higher orbit. If I fire my rockets opposite of the earths motion I go into a slightly lower orbit--this is the least energy solution.
You said: "Nuclear power really is very safe and controlled - the only reason Chernobyl happened at all was that some idiot had the bright idea to turn off the control system, and then turn off the back-up control system. Other than that and 3 Mile Island (which was a remarkably similar, easily avoidable situation),"
Chernobyl happened for the following reasons:
1. The Soviet government wanted to perform a test on the reactor's turbines.
2. The Soviet testers took control of the reactor (not directly--they just gave orders to the operators). The operators, whose job was reactor safety and who knew the reactor the best were no longer in charge or reactor safety. Now the test scientists who knew their test very well but not the reactor plant were in charge of the reactor.
3. The safeguards on the reactor were *intentionally* shut down in order to operate the reactor *intentionally* in an unsafe way (at low power).
4. The testers rushed the test because of schedule concerns.
5. The reactor was operated for full power during the day contrary to the testing schedule. Additionally the test was performed late at night when most of the reactor plant managers and supervisors (who would normally watch the tests like a hawk) were gone.
6. And the least significant factor, but the one that allowed the reactor to blow up: reactor design (power increases as water boils and a shutdown in the unsafe condition that the testers put it in would cause a brief power spike--coupled together it blew up the core).
Three Mile island was significantly different. In brief, it was caused by improper maintenance, improper value lineups on reactor safety systems, material failures, an incredibly overcomplicated reactor control and indication system, operators not believing their indications, and improper operator training and operation.
I'm not against nuclear power at all (I work as a reactor operator), but both of these accidents were mostly due to political reasons. In Chernobyl, the Soviet government did not have adequate respect for reactor safety and rushed a test. In TMI, the NRC (which IMHO had previously downplayed reactor incidents) did not regulate enough the maintenance and operation aspects of the reactor (and in particular the operator training). I think both of these problems have been fixed, but careful attention must be directed at all nuclear plants to not repeat these accidents.
You said: "The bigger problem with nuclear power is getting rid of the waste products. If someone could figure out a good way to launch those into the sun cheaply nuclear power would probably be the best solution"
The waste problem is completely political. If it wasn't for cold war/war on terrorism fears (no reprocessing of waste or use of breeder reactors) and irrational fears of storage (not in my backyard syndrome), waste could be safely reprocessed and the minimal high level waste could be safely stowed away.
I hope you didn't underestimate the difficulty on getting anything to the sun. The Earth's orbital speed is about 30 km/s. Kinetic energy is one-half the mass times the velocity squared. In order to get to the sun you have to cancel out the 30 km/s orbital speed (where 0 km/s is the Sun's 'orbit') and that will require enourmous amounts of energy. Doesn't really make sense.
The only reason SARS has killed less than 1000 people is the quick action from health agencies. A Dec 2003 CDC Morbidity and Mortality Weekly Report cites:Additionally the mortality rate of SARS varies based on age, where the WHO, for example, have estimated a mortality rate of greater than 50% for people over the age of 65. I don't really see why you think its ironic at all that so much effort is being put into a disease that is so dangerous (particularly to our elderly).
Just to be a little more clear:
the display reorientates on each use and is inactive after being used. This prevents a person from guessing that a person pressed '1' because he pressed the upper left key, and it prevents an infrared camera from doing the same based on the heat left on a pressed key.
The problem can be solved easy enough with a numeric keypad. Place seven-segment displays under the keys that are randomly orientated, like
7 5 2
4 3 1
0 9 6
8
This solves the problem for ATMs. If you dim the LEDs and polarize the light, you would make it more difficult for a camera to find the password also. Obviously this only applies to a numeric keypad (for ATMs and the like) since it would be a pain in the ass to change the lettering dynamically on a keyboard (at least for the user). The solutions for those using keyboards could be as simple as using a smartcard with a PIN number (which you enter on the randomized 10 digit display). The sooner we get rid of the biggest security risk on computers IMHO (guessable passwords) the better.
You said: "You are not creating energy, since the mass in energy in itself, it is what there's no law of convervation of mass, you just need the law of conservation of energy, since mass is energy ...
Sorry that I got to nitpick your nitpick:
Mass and energy are both human terms. They have no inherent meaning beyond how we interpret them. But one of our interpretations is that energy can do work. Now its fairly obvious that mass can be converted to energy and then do the work, but my point is, as far as interpreting as a linguist (which I am certainly not), mass and energy are certainly different. Now you can say mass is energy and energy is mass as long as you want but you have to be careful that you don't lose your meaning when you do so. For example, I can easily say that an electron has a mass of about 0.5 MeV, but I certainly wouldn't measure the mass of an apple in Joules.
You said: "Making energy would defeat Law of Conservation of Energy (and most likely Law of Conservation of Mass, since that's how most of the energy we're accustom to seeing is expressed). IANAP, but it really does get irritating to see this in writing... I guess you could reform it as: Any technology can be used for good or evil, especially technology that deals with releasing or storing energy."
Actually, my job does create energy (I work as a reactor operator). I just decrease mass by doing it.
You said: "the fact is that plutonium can only be used for weapons, period."
A quick lesson in nuclear physics:
A nuclear reactor operates by fissioning a fissible fuel (no suprise here!). While I'm not going to describe the physics of criticality you can look it up elsewhere. A fissible fuel is a fuel that will fission when hit by an alpha or a neutron. Due to the physics of criticality, alphas are not used (they have too short of a range and are rarely released from fission fragments anyways). Neutrons are used in two forms: fast and slow. A nuclear weapon will use fast neutrons (neutrons that after whatever reaction that created them have not been moderated) and a nuclear reactor will use slow neutrons (neutrons that have slowed down to the ambient kinetic energy of the reactor--typically by water or graphite).
It should be fairly obvious why only very heavy elements are used in fissible fuel. But due to a quirk in physics, only the odd atomic mass fuels work well. This is due to the fact that in order to cause fission you have to agitate the nucleus enough for it to split. Typically this is about 5 MeV of kinetic energy for an even numbered fuel. For an odd numbered fuel, the internal nuclear reaarangement gives this amount of energy so that a nucleus can fission with a slow neutron while an even numbered fuel needs a fast neutron with a very high kinetic energy.
What does this mean? U-233 is a slightly worse fuel than U-235 which will be a slightly worse fuel than Pu-239. Since Pu-239 is heavier than U-235 (which is used in an enriched form in nuclear reactors) it will be more suitable for nuclear reactors.
What about those fast neutrons, will they work? Yes, but common sense says that if they are slowed down they will have more interactions before escaping from a reactor, so they would work better. Nuclear bombs don't have the time for neutrons to slow down to ambient before interactions so they depend entirely on fast neutrons (the converse shows why a nuclear reactor can never explode like a nuclear bomb).
Any technology can be used for good or evil, especially technology that makes energy. Alfred Nobel, the inventor of TNT, knew this only too well. He created the Nobel prize so people wouldn't remember him as the creator of a weapon.
As far as understanding what technology's consequences are: technology is part of society. Its not that somehow society and technology can be seperated and analyzed so that only the 'good' technology can interface somehow with society. Society is what causes the technology to exist in the first place and continue its development. Society has as much as an effect on the dangers of the technology as the mechanics of the technology itself.
Some may argue that technology can't be released until its full impact on society is known. Thats impossible, as a modern technological society can't exist as a free state with blantant censorship. These issues aren't suddenly new. Its the same problem that engineers throughout history have had to deal with when they realized that their peaceful invention could have dangerous implementations. Research DNA, make more powerful bioweapons. Reasearch nuclear power, make the most powerful WMDs. Research network technology, make the powerful network warfare that we saw in the beginning of Gulf War 2.
Correct the society and the consequences of the technology will follow along.
I've said this before and I'll say it again: personal attacks do not win arguments, they are only intended to confuse the facts. Only the truth wins arguments, and it doesn't matter who says it (it could be a trashman or Niels Bohr himself who says it, it doesn't matter). Additionally, its generally not a very good idea to make generalizations or try to draw conclusions from the behavior of a person you have never met. Chances are your conclusions are off. Now to get to my point.
You said: "But it is possible to play a character motivated by a need to win battles, and for that character, optimizing combat effectiveness isn't munchkinism, it's exactly what their character would do."
And previously: "Some of us want to play the role of a master of fighting prowess. who puts evil abominations to the sword."
I think you missed my point on the halberd. Its not a general purpose fighting weapon. Its meant to be a can opener for heavy armor. How exactly is using it on the field a good idea? If you would put yourself into that role I think you would understand that in general field usage you would get killed very quickly. If you put yourself into the role of a master of fighting prowess, for example, I would expect you to more likely pick a weapon that is more general purpose.
Now let me phrase my point on the halberd: a role player is a person who picks it as a weapon because he or she intends to attack heavy armor and it is the logical weapon. A powergamer picks it because a simplistic game world gives it more points of damage while not giving the significant detraction that a person using it would have basically no defensive ability in one on one combat.
You said: "Powergamers are role-players"
This reminds me of an old problem that existed in Ultima Online. At one point the halberd was the best weapon for a fighter. Now if people were actually roleplaying they would probably pick weapons more suited to different fighting roles than the halberd which is a fairly exotic military weapon. You could probably expect some people to play knights using swords as their weapons, others as archers, etc. But did this happen? No of course not, everyone picked the halberd. Later when a game patch came out that made the kitana the most powerful weapon, did those people stay with the halberd? Nope. They jumped ship for statistical reasons.
How is this roleplaying? How is knowing that your weapon will deal 2 points more of damage a turn on average versus a competitor the deciding factor for someone who wants to play a role as a knight (as an example)?
Its powergaming, not roleplaying. Roleplaying is taking all the good and the bad of a character and making due with it. When you powergame, there is no role being explored; it more like fun with statistics.
You said: " Problem is that D&D's number-crunching sucks and instead of focusing on giving the player a thousand numbers to concern himself with, it'd be better to make a fun game."
Thats why the White Wolf games are so lax on numbers and vague on what some attribute to your ability will do. The point of a RPG is to role play, not to kill monsters and powergame. Unfortunately, most of the public thinks the latter is what an RPG is. It is painstakingly difficult to talk about a pen and paper RPG without others thinking your are a D&D powergaming freak. Its sad really, since RPGs are a great intellectual game. Once anyone focuses more on making the RPG compliant so that the numbers balance out, they've lost the point of the game altogether.
You said: "Here's the thing you see, there are a million and one ways we can all use less electricity and keep every gadget we run and more, here's some examples: monitors, ...lightbulbs, ...appliances, ...trash, ... heating"
How about we focus on the areas where power saving is the most. An average home uses about 2 KW of power. More if you use electric heating. The greatest uses are:
(1) Heating (>1KW while cycling)
(2) A/C (>1KW while cycling)
(3) Washer & dryer (~1KW)
(4) Stove (~1KW)
(5) Microwave (~0.7 KW)
(6) Refrigerator (~1KW when the compressor is running)
(7) Misc entertainment (Tv's, etc) (~0.5 KW)
The first 2 use the most power by far. Properly insulate your house and you dramatically cut down on energy consumption.
The third can be cut down by making sure your washer and dryer are full when operating (fewer times they are operated). Twist out the excess water (or use a closeline) from washing and you will significantly cut down on the dry time.
The fourth can be cut down if you use a toaster oven for small meals. No reason heating up so much metal just to cook a TV dinner.
The fifth through seventh can be cut down by using energy efficient models.
Now here's my point: Lets not focus on replacing lightbulbs when your house is radiating 500 W of heat! Focus on big things!
You also said: "I really wouldn't expect an American to understand this."
This elitest attitude is totally unfounded! I can't believe you thought it appropriate at all to make this statement. This is nothing more than a personal attack directed at each American reading this board. But even though you have this elitest attitude, I will try to educate you on one thing: personal attacks never win arguments. They are only made to confuse the argument. There is only one thing that can win an argument: the truth. It doesn't matter if the truth is said by Neils Bohr, and American, or a trashman: the truth is all that can settle an argument. No more personal attacks please, it makes you look foolish.
You said: " Why is it that we have this never ending need for more powerlines and more electricity rather than looking for alternatives with any real conviction?"
The reason is because most of the power generated is used by industry, not by houses. I used to live in a town of 30,000 that used 30 MW of power for residential areas. Just one plant outside my town used 60 MW of power. If you conserve power, use alternative energy, etc., it will do nothing to curb the growth of energy use. Industry survives by growing. To give you another example, the town that I was just talking about used to have a population of 100,000 where 30,000 were miners. Now it has less than 500 miners and they pull more minerals out of the ground now than they did with 30,000! Obviously there are tons on industries that could tell the same stories, because machines (which run on electricity, not magic) and increased automation have replaced the need for people. And industry will continue to build bigger and use more power. The only way that you can stabilize and lower energy usage is by enacting laws that prevent industry to grow! Of course, I would love to see the debate in Congress over that one.