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Comment "Maybe", except not, unless you ignore most of it (Score 1) 389

> End-user prices for electricity are maybe 3x times higher in Germany

Maybe, except no. The wholesale spot price is three times higher, but German households pay more in green energy surcharges than they do in actual per kwh production costs. You have to ignore MOST of the charges on the household electric bill to say it's only three times as much as US households pay.

> In fact, Germany exports a lot of electricity (e.g. to France).

You got your two countries mixed up. France is the world's number one net EXPORTER of electricity. As in, they sell more electricity than other other country in the world. Check IEA if you think I'm mistaken. The cost in France is half of what it is in Germany, IEA numbers. They aren't buying it up from Germany for twice as much as they sell it for. France uses nuclear plants to produce 75% of that electricity.

> solar was 30 TWh (4.7%)

So they pay ten times as much (or let's pretend it's three times as much) and for all that extra money, only 4.7% is solar.
If each family paid $5,000 / month for their electric bill, maybe 20% of it could be solar! The other 80% could be bought from the French nuclear plants.

> The idea that the grid provides only 12.8% percent of the electricity is Germany is so wrong that I am speechless.

You numbskulls keep making the same mistake. The "50%" headline here on Slashdot made the same mistake, and I explained it then, quite clearly.
Since you don't seem to have the attentions span to read the exhaustive explanation, here's a short hint for you. Meditate on this quote:

"You're not going to be charging up a Telsa in Germany!"

Comment 85% of the earth (Score 1) 389

> Somewhere either the sun or the wind is out, when it isn't in another place, so the electricity just gets redistributed from where it is to where it is not?

Where "somewhere" means up to 15% of the world, never more than 15%. For several hours, only the middle of the Pacific ocean has midday sun. You can't run mile-wide power cables from the Pacific to the UK. Remember, your eyes can see in either candlelight or in full sun, which is a MILLION times brighter. Though morning and late afternoon look "light" to our eyes, there's darn little energy there. Solar-electric pretty much captures energy from 10AM-2PM. Most of the time, the bright sun is on the other side of the planet, and that's pretty far away.

They did NOT momentarily get 50% of their energy from solar. They momentarily got 6%-7% from solar, when the sun was bright and nobody was at home because they were at work. The headline was wrong, in two different ways. I'll explain how in a moment.

Imagine if Germany shut down all of their electric power plants, then connected a Duracell AA battery to the public grid. You could honestly say that a single AA provided 100% of the power on Germany's public electric grid at that time. Of course, there wouldn't be a usable amount of power available from the grid, so everyone would be running of their own gas-powered generators, but all of the grid power would be coming from that one AA battery.

What Germany actually did was a less extreme version of the above. They actually shut down some power plants, not all. Because of this, electricity is relatively scarce in Germany - it costs ten times as much as it does in the US. You're not going to be charging up a Telsa in Germany! Not for $320 per charge!

Because the public electric grid in Germany is so expensive, 87% of the power people use comes from somewhere other than the public grid. The grid provides about 12.8% of the power for the country. For a moment, half of that 12.8% was from solar. The other 87% + half of 12.8% = 93.8% was not from solar electric.

Comment would be awesome if we could. I want 0.0001% of $ (Score 1) 389

It's tempting as hell, I know. All that energy right outside. Also, if I could collect 0.00001% of the money in the world I'd be enormously wealthy.

The problem is, I can't collect even that tiny percentage. For solar electric, the fact that bright sun is only available for a few hours per day is an absolute deal-killer. Let's pretend for a moment that we had magic solar panels that collect a thousand times as much energy as what falls on them , and they're free. All we have to do is store the energy for overnight use. I have an idea, let's use the solar power to pump water uphill, then at 3PM we'll let it start coming back down, through turbines that generate electricity. Let's see where we can put these reservoirs. If we calculate the required amount of water X height, we find that the reservoirs need to cover 80% of the United States. That's right, you can power the country by putting most of it underwater. And that's with magical solar panels that are free.

The amount of energy we're talking about is so far outside most people's experience that we have a hard time reasoning about it. Solar IS good at heating things. Solar energy is good for growing food. It's good for a lot of things. It absolutely sucks balls at making electricity, because we need electricity in the evening, at night, in the morning. Also because solar electric is ten times as expensive than the alternatives. People simply can't afford a $1,500 / month electric bill.

There is ONE way you can turn solar into electricity that's practical on a small scale only. You use the sun to grow plants, then burn the plants to generate electricity, even after 2PM. That does have the minor side effect of releasing a bunch of CO2 into the atmosphere. And of course the plants need water, lots of water. Lots of land too.

Preheating water with solar heat: a good way to save energy and money.
Turning light into electricity: a good way to power a small calculator, only. Doesn't provide enough power to run a watch. (But a tiny watch battery does.)

Comment What difference now does it make? :) Sunk costs (Score 3, Insightful) 364

The F-35 probably shouldn't have been built. At least, it shouldn't have been built the way it was. "Been built" is the key phrase. Most of the excess cost is already sunk. Nine countries have signed on to buy it. We can't reverse time and get the money back, and starting over from scratch would both a) cost more and b) lose most of the partner countries, meaning the US would pay more of the cost.

Yes, maintaining planes costs money, and the F-35 is no exception. Is someone suggesting that the US should have no planes? Of course not, so maintenance costs will be incurred. There's no choice to be made there. I suppose we could spend nearly as much trying to keep F-15s flying. Would that be better?

Comment for only $1,500 / month, average home. Plus night (Score 1) 389

You can save a few bucks by pre-heating your hour water in the sun.

You can also power your refrigerator in the middle of the day, when you're not home , by paying $1,500 / month for solar electric. One of these two makes sense.

Every bit of money or time spent taking about solar electric is spent NOT working on something that can actually solve the problem, so it helps guarantee that we remain stuck with coal. If I owned a coal-mining company, I'd promote solar-electric to keep people distracted from nuclear and anything else that might actually be practical.

Comment yep, thanks for pointing that out (Score 1) 389

> just be careful with your numbers.

Absolutely, thanks for pointing that out. I want to post accurate facts, both for the credibility of the argument and I learn something.

Researching solar, I first found out that while solar electric MIGHT be a useful supplement at lunch time, there is zero chance of it ever being viable for primary power. However, in looking for accurate, objective data, I also learned that solar pre-heating by running my hot water pipe across the lawn can save me a lot of money here in sunny Texas.

Comment 71 people. More from coal that year (Score 1) 389

71 people died from Chernobyl. That same year, more people died from coal.

PREDICTIONS of increased cancer rates around Chernobyl vary. The average prediction is somewhere around 4,000. Compare 170,000 killed when a hydroelectric dam went. Nothing is perfectly safe, but the worst nuclear accident in history isn't as bad as the worst wheat accident.

Comment Greenpeace founder says he was dishonest about tha (Score 2) 389

Your post is based on a slight misunderstanding of radioactivity, a misunderstanding that guys like Patrick Moore of Greenpeace purposely created to trick you. Since founding Greenpeace, Moore has realized he was foolish to BS people and he's changed his tune. Moore now says:

Within 40 years, used fuel has less than one-thousandth of the radioactivity it had when it was removed from the reactor. And it is incorrect to call it waste, because 95 percent of the potential energy is still contained in the used fuel after the first cycle. Now that the United States has removed the ban on recycling used fuel, it will be possible to use that energy and to greatly reduce the amount of waste that needs treatment and disposal. Last month, Japan joined France, Britain and Russia in the nuclear-fuel-recycling business. The United States will not be far behind.

Moore skipped the fundamental lie / misunderstanding though. There ARE substances that emit radiation very slowly, over a long period of time (trees are an example of this type). There are also substances that emit radiation quickly, quickly enough to harm you. What Moore didn't tell you is that THESE ARE TWO DIFFERENT TYPES OF WASTE. If you think about it for a minute, it makes sense. A candle burns for a long time. Gunpowder burns quickly, releasing its energy all it once. All that energy being released at once is dangerous. Gun powder dangerous BECAUSE it is fast. The energy from the candle isn't dangerous BECAUSE it's being released so slowly. The release of nuclear energy is just the same. There are some materials that take 4,000 years to release their energy. Since it's so slow, you'd need to sit next to it for 800 years to be affected. Then there is the waste that releases enough energy to affect you in only one year. In four years, it's released most of its energy and it is safe to have around the house.

Comment Germany gets 2.3% (Score 3, Informative) 389

Germany gets 2.3% of it's power from solar electric.

Not even for a moment did they get half their power from solar. The headline was wrong/,misleading times two.
More like 6%, unfortunately. That's nice and all, that when the sun is shining really bright, for five minutes you can get a significant amount of power from solar.

Then, within three hours, it's no longer 10AM-2PM and solar energy drops dramatically. (Our eyes see brightness roughly on a logarithmic scale, so what we perceive to be not quite as bright as bright is actually 90% less energy). For example, the moon looks to be maybe 5% as bright as the sun. Actually, the sun is 400,000 times brighter.

So yeah, solar is a great way to REDUCE the demand on your base sources during lunch time. Kind of like regenerative braking REDUCES the demand on the engine. Neither is, or ever can be, a primary energy source.

Comment Too late. Fission 80,000 times safer than hydroele (Score 1) 389

Fusion will be great when and if it happens. California will probably be underwater by then, at least if you believe in the boogeyman version of global warming.

In order to survive long enough to eventually develop some amazing energy source, we need to take action now, using power plant designs we can ramp up today and have reliable energy. Natural gas releases half as much CO2 as coal, so that's one improvement. Nuclear fission is awesome except for the worries about safety. Well, we've had nuclear for many years, and we've had other options, such as coal and hydroelectric for many years. Our experience shows that coal and hydroelectric both kill hundreds of thousands as times as many people as nuclear. Nuclear power has killed about 5 people, while just one hydroelectric dam failure killed 170,000 at Banqiao. So the "problem" with fission is indeed the WORRIES about safety - the actual safety is far better than any alternative.

Comment Interesting, but not a Turing machine, unless is (Score 1) 26

We're way off in the weeds here, of course, but that's cool. I don't mind playing in the weeds.

What you've done there is analogous to Dear Leader's argument "it's Constitutional because it is not a tax and is a tax". You've tried to say "it can write the single value 00000001, which is eight values". Either that's one value or eight, pick one.

The definition of a Turing machine has requires very few capabilities. One of the very few things required by the definition of a Turing machine is that is has to be able to update memory one value at a time (block writes aren't good enough). That's the DEFINITION of a Turing machine - it's a machine that writes individual symbols to a strip of tape of other storage.

You've defined a language that can only update eight bits at a time, and additionally you've said it updates them only in certain patterns. That's not Turing complete.

If we want it to be Turing complete, we can interpret it as one value by saying that the LANGUAGE writes "1" and the HARD DRIVE happens to store that physically with eight molecules. The language would then be Turing complete since it's updating the single value "1". Fine. The language can write 1010101, 11111, 0000, 01010, or any other series since it's writing one value at a time. Perhaps the hard drive stores "10" physically as 1111111100000000, but the hard drive is going to read back what was written to it. Write a "1", get a "1" back. That's part of the definition of Turing complete because the storage in a turing complete system can be like a dumb piece of paper - it doesn't change what you write to it. Given that the tape doesn't change what's written to it, the language can write valid machine code and get valid machine code back.

You can't have it both ways. If "1" is one value, it can write "1", then write "0", in whatever pattern is needed to produce valid machine code. If it can only write the eight separate values 0,0,0,0,0,0,0,1 that's not a Turing machine.

Comment ps - I wouldn't want to write COD in Postscript (Score 1) 26

Ps, it would certainly be EASIER to write Call of Duty in some languages than it would in others. It would be difficult to get it to run QUICKLY in some languages (actually that's true of all languages). It could be done, though, and that's point. The question isn't what CAN the language do, the question is what it's best suited for. Just because you CAN write a pixel shader in Perl doesn't mean you should.

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