Assorted links


Links #3 and #6 are interesting in view of the post immediately preceding this.

Gambling worked out well for Las Vegas, but it seems that you can have only one Las Vegas in the world, or maybe only a handful of them. The East Asian Las Vegas maybe shouldn't be in China.

Former Portuguese colonies are usually pretty cool places. Macau could capitalize on its heritage and draw steady earnings as low key tourist conversation such as Goa and the Brazilian colonial cities. It wouldn't be as much $$$ as becoming the next Las Vegas, but be a more secure source of income.

# 3: This is the consequence of widespread uncontrolled doping... Also an excruciating schedule (Vince Mcmahon has a lot of blood in his hands...) ... It might be all fake, but the dangers are quite real (is there a "real sport" with a comparable mortality rate?)

6. The spectacle of a couple of U.S. Senators admitting, no, bragging, that they don't use email, don't even know how, prompted Elspeth Reeve to write an essay in which she concluded that the baby boom generation is the Laziest Generation. Being one myself, a baby boomer not lazy, I searched for evidence that would contradict Ms. Reeve. It didn't take long. Generation Y Americans (those born after 1980 and including Ms. Reeve I do believe) lag behind their overseas peers in literacy, numeracy and problem-solving in technology-rich environments. Researchers at the Princeton-based Educational Testing Service (ETS), who conducted the study, administered a test called the Program for the International Assessment of Adult Competencies, to measure the job skills of adults in 23 countries. Not only do Gen Y Americans lag far behind their overseas peers by every measure, but they even score lower than other age groups of Americans. “We really thought [U.S.] Millennials would do better than the general adult population, either compared to older coworkers in the U.S. or to the same age group in other countries,” says Madeline Goodman, an ETS researcher who worked on the study. “But they didn’t. In fact, their scores were abysmal.” I suppose it would be accurate to call Gen Y the Stupidest Generation. The economy may or may not reduce the number of marriageable men, but it does seem to be contributing to stupidity among those, Millennials, most affect by the Great Recession.

I was born in 1970 (in other words I'm an Xer). I'll admit to not being that impressed by the knowledge or social skills of most of the Millenials I've come across, which I attribute to the effect of the steady dumbing down of US culture. But they've seemed much better than Xers and Baby Boomers on being comfortable around electronic gadgets. Is either impression wrong and if so how?

"Comfortable around electronic gadgets" doesn't imply knowledge of the systems. Some people eschew certain pieces of modern technology precisely because they do know what is going on under the hood.

That doesn't have to be bad -- most people riding in an airplane couldn't fly it if their life depended on it, and that's okay. But we wouldn't see how comfortable they are with travel as a measure of their avionics skills.

Assuming this study represents reality, which Generation was entrusted (and often paid) to teach Millennials these skills?

Exactly. Boomers suck at parenting/teaching?

Kids these days, am I right?

Damn right. When I was a kid and I wanted my Commodore 64 to run anything, I had to type-in pages of BASIC from a gaming magazine first. And I might just get a floating balloon made of letters from the alphabet. And that's assuming I didn't have commit a typo somewhere.

When I was a kid we had to GOTO LINE 10 uphill both ways!

IBM punch cards when I was in college. They did have DECwriters but they were for the slightly more advanced students (we just used them to play Star Trek).

And a fancy programmable calculator that could run BASIC (but only BASIC) that my high school acquired my junior year.

They are always on the lawn. Why won't they get off?
Back in the day, when you yelled, they would a go a scamper. Of course, I had an onion on my belt, which was the style at the time. I didn't have any white onions, because of the war. The only thing you could get was those big yellow ones...

Ha, ha, ha.

How would students from today fare taking tests from 1965, or 75, or 85 etc. I've always suspected they would bomb them horribly. Why doesn't someone try it out?

Don't forget to give a modern test to the kids 50 years ago.

I've seen tests that are given to local grade school kids. The instruction language seems unnecessarily complicated. The math problems with the blocks seem counter intuitive to me. I'm not sure how 1965 kid would react to them.

Maybe he or she would want to go forward in time and punch his or her grown-up self.

On the contrary, my impression is that academic standards have been rising over time. For example, before the 1980s, calculus wasn't really taught (pdf) until the graduate level. Even if courses were called "Calculus", they tended to only cover precalculus topics. Then they implemented AP Calculus courses at the high school level, which is expected as a prerequisite for undergraduates going into STEM or even some social sciences like economics.

Anecdotally, my parents were both technically minded people--STEM majors--and they were blown away by the mathematical expectations of my undergraduate economics courses. I compared my modern economics textbook to my father's book (Samuelson). It's funny how much simpler (and sometimes wrong, by modern standards!) the old books are.

In other words, I think today's undergraduates would blow their ~1960s peers out of the water on such tests. I don't think that has to do with anything to do with inherent differences in the cohort, but rather a combination of the today's better instructional tools (e.g., computers) and more advanced science (e.g., Black-Scholes wasn't taught before the 1970s but is routine for economics undergrads now).

Sorry, the second sentence above should read "until the undergraduate level."

Thats a good point and an interesting observation. When I was writing the question I had in mind K-12 rather than undergraduates. I'm guessing the typical striving college bound student is of a much higher quality than before, while the average to poor student would be doing worse. "average is over"

Both ends of the bell-curve of college students have been stretched out. Someone who was at the cut-off from the top/bottom 5% 30 years ago is probably top/bottom 10% today.

I suspect a u-shaped pattern. I agree that my kids curriculum was more rigorous than mine growing up in the 1970s.

But the 1970s was the peak of progressive education theories. The college-bound generation before mine was, I think, more rigorous than mine and perhaps more rigorous than my kids, but the college-bound population was decidedly smaller back then too.

Well, put it this way - a doctor today wouldn't do well on a medical board exam from 1905, not because today's graduates don't understand medicine, but because the chemicals used for treatment back then are now known to be poison and the official answers to the exam are wrong. Science, engineering, and even mathematics have advanced considerably in the last 50 years. Using science and with greater access to source materials, our knowledge of history has also increased.

Even at the time of administration, tests have observable defects, anyone arguing for the 1965 answer sheet would need to meet a very high burden of proof.

As expected, it's a different picture when you account for race:

In what ways do race/ethnicity influence our understanding of the overall performance of
U.S. millennials? As a means of comparison, 64 percent of millennials in the U.S. performed below
the minimum standard (below level 3) in numeracy, compared to 47 percent of millennials in the
OECD average. Fifty-four percent of White millennials and 52 percent of Asian millennials performed
below this level, as compared to 83 percent of Hispanic and 88 percent of Black millennials.

It is interesting, though, that White Americans(and even Asians) performed below the level of White Europeans. On the PISA, White kids scored higher than most of Europe.

My point, besides defending my generation against a generalization, seems to have been missed. Millennials, I would argue, aren't learning as they can and should because they have been affected by the recession more than other generations. For them, the aughts and beyond, the years they came of age, have been a disaster, a brutal war and a collapsed economy, and the future seems to offer little in the way of hope, as Congress is ginning up another war, this one against Iran, and even the prospect for the economy don't seem that bright. Indeed, there are many case studies that conclude that the Millennials will never recover from their experiences in the aughts and beyond, like some stigma they carry with them throughout their lives no matter how much the economy recovers. Failure doesn't make one stronger, failure is "powerfully demotivating" according to Peter Thiel (who will be interviewed by Cowen in a couple of weeks).

I don't think it defends Boomers at all, though. You guys had the power in the aughts and beyond. You created a world of comparative shit for us to come of age in. You got through school and then jacked the cost up to support hordes of Boomers in bullshit administrative positions. You cut your taxes while still spending on all sorts of goodies, including blowing up foreigners for your entertainment. Now, as you finally approach and enter retirement, you'll vote to increase taxes on wage income while keeping taxes on investment income low, and grant yourselves additional Medicare benefits.

Exactly. Boomers suck at running an economy?

Millennials, I would argue, aren’t learning as they can and should because they have been affected by the recession more than other generations.

In the real world, millennials are in school more than ever, it just isn't making them have higher IQs. During the recent recession, enrollment in colleges increased. I oppose the stupid wars and their catastrophic economic and political effects but I don't see how they impact people's 'learning.'

"For them, the aughts and beyond, the years they came of age, have been a disaster, a brutal war and a collapsed economy,"

Are you seriously calling the Iraq War a brutal war? As compared to Vietnam, or Korea, WW2, WW1, the US Civil war, etc? Furthermore, the Iraq War (& Afghanistan War) had very little effect on the experiences of most Millennials.

Here's an image my younger, Millennial step brother combat veteran forwarded to me:

The actual data in the report I linked shows that the average score on the numeracy test is slightly higher for the 16-34 age group than for the 35-65 age group. Which one should expect considering the natural decline in intelligence with age. By comparing scores from 1994 and 2012 on their literacy test they found a decline of .06 standard deviations. The fortune link was probably just pulling stuff out of their ass so that they could have a story.

I don't think millennials are appreciably dumber than the older generation, but they are more disinterested in certain things like politics and world affairs, all else being equal.

No, they are just YOUNGER. When they get old like Boomers they will be just as into politics and world affairs. For pete's sake this line of argument has been going on literally since Socrates.

I think that without loss of generality the researchers failed to adequately measure job skills. Assuming the assessment is accurate, ETS researchers, being from the US, lack the job skills necessary to conduct the study. Otherwise, the assessment is inaccurate and we have proven what we are trying to show. The fact they thought they would get a different result than they did also supports the theory they don't know what they are doing, as does the recent revisions to the SAT or basically any life experience with an ETS exam.

"#5. Advances in beaming solar power from space."

Econ FAIL.

The article has it exactly backwards, at least in the short to medium term. (say the next 30 years). If the receiving gear is light weight, or at least of lighter weight than the equivalent solar cells on a standard satellite (or the International Space Station for that matter), then it makes far more sense to use this technology to beam power to space.

Currently solar cells mounted on the ground produce power much more cheaply than solar cells in space. Even when you factor in enough energy storage to turn the solar cells into the equivalent of 24/7 base load production, Earth based solar cells are more cost effective. So, it makes no economic sense to use this to beam power from Space to Earth and probably never will make sense, as long as the solar cells have to be launched from the Earth.

I wouldn't expect to see Space to Earth power transmission until we have a space based solar cell manufacturing industry.

What if the rockets were solar powered?

I don't know if you were joking, but

Urstoff, rocket fuel is tiny fraction of the cost of getting payload into space so producing the fuel using solar power wouldn't be much of a saving. Currently we could use solar electricity to electrolyse hydrogen from water instead of reforming natural gas for rocket fuel. The cost of electricity would need to come down for this to be competitive, but as hydrogen can be stored it could be generated during periods of low electricity prices. For example thanks to our wind capacity and rooftop solar, wholesale electricity prices may drop to zero here in South Australia in a couple of hours. (As it is basically impossiible to stop hydrogen leaking it can't be stored indefinitely, but it can be stored for use as rocket fuel provided launches don't become too infrequent.)

Solar cells in space are usually envisioned as being base load power, without any storage. It's a matter of choice of orbit (and distance from the receivers). A lot of smart people think solar is _only_ going to be viable when it becomes space-based.

Obviously this is dependent on a large drop in the price of space launch, but it looks like that's actually starting to happen now. It's an idea we should probably check in on again in 25 years. It's the other energy production technology besides nuclear that works at a large scale in a Real Serious AGW world, should that materialize.

If we're going to beam power to spacecraft, it probably makes sense to use a laser to illuminate solar panels. You get much better pointing accuracy that way.

All that said, the article didn't contain enough information to say whether this is hype or real.

"at least in the short to medium term."

Reading fail on my part. Sorry.

Yeah, this isn't a near-term technology because it costs too much to launch things buying from government contractors.

Lord, solar power is already viable. Here in Australia rooftop solar, which competes with the retail price of electricity and not the wholesale price, is already the cheapest source of electricity available to most Australians. And utility scale solar has been bid in at 6 cents a kilowatt-hour in the UAE and 8 cents in the US.

But that goes against Lord's notions of the price of solar in the '70s and how foolish it all was, and how the drive for cheap oil should be the only energy goal .

About 80 gigawatts of new coal capacity was built in 2011 but it fell down to 49 in 2013 and less last year. And this is mostly all due to the decreasing cost of wind and solar generating capacity which can now generally be built at a lower cost than new fossil fuel capacity. But a surprisingly large number of people seem to be completely unaware of this. Why, it's almost as if they don't want to know.

You are correct I believe in your analysis, but the free lunch economics that Reagan sold America depends on magic bullet solutions that can be patented and then used to generate huge monopoly profits to compete with the profit from controlling the pillage and plunder of natural capital and selling it off to be burned.

Capitalism fails to meet the requirements of free lunch economics.

First, building capital assets to harvest the wind and sun on the scale necessary for civilization to continue for another 250 years and more requires paying millions of workers. Free lunch economics demands labor costs be eliminated.

Second, free lunch economics demand capital assets increase in price - capital gains. But if you build a wind or solar farm, its price can never increase to produce the required capital gain: first, economies of scale in production ensure the next farm will cost less to build, driving down the price of existing farms. Second, capital always decays; this is called depreciation and is the economist's method for accounting for capital losses that reality economics requires.

Energy capitalism is boring. One simply builds and builds and builds more and more energy harvesting, storing, and usage capital assets, and paying tens of millions of workers to do the manufacturing and construction, and then selling electricity for zero profit, just a market rate of return on invested capital.

Still, the free lunchers hope for the magic bullet that will let they make huge profits without working or paying workers to work selling the free electricity they monopolize. How anyone pays for this high profit energy got for free is a mystery, but in free lunch economics, workers are not consumers and consumers are not workers, so it seems consumers have infinite cash. Or credit.

The photovoltaics used on satellites are very expensive because, due to the cost of getting them there, it makes sense to use the most efficient and reliable ones available.

But space-based power presumably would use giant mylar-film mirrors to concentrate sunlight onto something that could be used to convert that energy into electricity and then microwaves. As on that ground, that something might be some type of heat engine (liquid sodium as a working fluid?) rather than photovoltaic solar cells.

Perhaps the real "gotcha" is that a beam with high energy density could be used as a weapon (perhaps by anyone who could hack into the beam-control satellite)?

As said below, the beam isn't dangerous, and even saying "it's mostly mylar!" doesn't solve the problem. Say what the amount of mylar and solar cells you are going to have, their mass, and their launch costs.

Seems a bit myopic to call a less-than-15-year-old wall street dream, "old Macau". Considering that Macau was a 400-year-old Portuguese, and still has remnants of a past that pre-date not just the new casinos, but Communist rule and European imperialism.

@#1 - this was I think the premise of a short story by sometime sci-fi writer Jorge L. Borges: "If pi were truly random, that would mean that the number sequence in pi would never repeat itself, and -- because pi is infinite -- it would contain all patterns in existence. Any word that you can think of, when encoded in numbers, would show up in pi, says Kryzwinski. So would the entire works of Shakespeare, all possible misprints and permutations of Shakespeare, and even, if you were patient enough, pi itself. As Cornell mathematician Steven Strogatz writes for The New Yorker, pi is so special in part because it "puts infinity within reach." And all of the troll bait in the comments section of MR!

"So would the entire works of Shakespeare, all possible misprints and permutations of Shakespeare,"

I liked the various stories involving Monkeys banging away at typewriters better myself.

Borges was not exactly mathematically literate. Each additional number of pi adds complexity and therefore each additional number of pi (yes I am using the English word number where the average person would use digit, there is a reason for that) makes the prospect of any given future complex sequence of numbers marginally less (or equally less, if that helps) likely. The kind of infinite process the little word problem Borges - whose skills were immense, but were not of the mathematical kind - describes goes more to an increasing likelihood of future pulpish gray goo, not to an increasing likelihood of future triumphant eras of Shakespearean reiterations. Otherwise said, an infinitely decreasing likelihood has no reason, as John Locke might have said, to ever reverse itself. Or, your first random infinity will have little to do with Shakespeare, and your next infinities will in turn have infinitely less to do with Shakespeare, and so on, ad distantiam infinitam semper et in aeternum conandam. Numbers have no conscience and will always be different from people like you and me.

How much of this pi pop-innumeracy is due to IFLS and it's party of science legion? Science-denier is looking more and more like heretic every day.

#5 - While there are certainly technical problems with space-based solar power, the real issue is economics.

We can make all the solar power we want right here on Earth - the problem is not in making it, but in making it cost-competitive against other energy sources.

Unless the cost of space-launch drops by several orders of magnitude, it will never be cost-effective to beam solar power back from space. And the fundamental physics of it requires that any losses incurred in beaming the power back to earth, converting it back to electricity and distributing it will be smaller than the gains of putting your solar cells in orbit. Yes, you gain 24/7 access to power, but you can't beam it back 24 hours a day unless your satellite is in geo-stationary orbit. That means beaming the power over 24,000 miles instead of a few hundred miles in LEO.

If you want to put your solar satellites in low earth orbit, you'd need a whole constellation of them to be able to provide power 24/7.

"Unless the cost of space-launch drops by several orders of magnitude, it will never be cost-effective to beam solar power back from space."

Launch costs only need to drop low enough to create a space based industry. It will probably be more expensive to launch the solar cells directly from the Earth than it will be to mine the materials from the asteroids and build them directly in space. At least for a significant area of solar cells.

"Yes, you gain 24/7 access to power, but you can’t beam it back 24 hours a day unless your satellite is in geo-stationary orbit. That means beaming the power over 24,000 miles instead of a few hundred miles in LEO."

Does that matter? More than likely there's no loss from going through vacuum. So, the difference in beaming the power through 600 miles of atmosphere vs 23,400 miles of vacuum + 600 miles of atmosphere is negligible. And beam dispersion probably doesn't matter, since most of the plans I've seen assumed that you would use a very wide collector on Earth in any case, just for safety.

And for political reasons of course. I don't suspect that Russia or China would regard a US spaced based "power" generating station with a narrow beam very kindly.

We haven't come close to running out of, er, space on Earth to put solar panels. Why go through the expense of launching them into orbit to beam back the power?

If you could make SPS out of material already in space, that changes things.

Launching is silly. If someone is proposing it, ask to see the math: how much are they putting in orbit, for how long (things do degrade in space), and how much power will it collect? They probably haven't even gotten that far.

I think I remember that a correctly oriented solar panel in GEO generates 7x the power of a well-sited one on earth. It's also constant power which integrates well with the grid. So if it costs less than 7x the the raw panel cost to launch it and build your receiving antenna, it's plausible. The kind of degradation caused by the space radiation environment is dealt with by re-annealing the cells, which isn't a crazy thing to think about doing in place in an automated fashion.

For mainstream applications, the whole thing hinges entirely on launch costs.

There are some applications, like easy-to-assemble power plants for remote areas, that might provide a market even if the power costs more than traditional less-portable forms. I believe DoD has looked into this.

The weight of the solar cells required for a 4GW power station ranges from 4,000 tons to 80,000 tons, depending on the material and whether we can do very lightweight manufacture.

At current launch costs, the heavyweight version of the cells would cost about $300 billion dollars to get into orbit. As important is the amount of energy that would expended to get them up there, which would have to be recouped over the life of the project.

Assuming SpaceX can build a reusable heavy lifter, launch costs might come down by an order of magnitude. Then you'd still be looking at $30 billion dollars just to lift the panels. If you can cut the weight of the panels in half, you'll still need $15 billion just for those.

Then there's the cost in mass and energy to keep the satellite on station - those solar panels are going to act like a solar sail when sunlight hits them, and you'll need a constant force to counteract that. Ion engines, probably. They are very efficient, but still burn fuel. Then there's maintenance, micrometeorites, damage from cosmic rays, thermal cycling, all kinds of things.

In engineering the devil is in the details, and in a project like this there are a lot of details.

"I think I remember that a correctly oriented solar panel in GEO generates 7x the power of a well-sited one on earth. "

Assuming that's correct, remember that less than 50% of that power will make it out of the ground antenna system, and then maybe another 5-10% of that will be lost to transmission losses.

So you might wind up with 3X more power per panel. For that it's worth lifting them into geostationary orbit? Doesn't seem likely to me.

I think it's 7x all-in. But I'm not quoting a source, so take that for what you will.

Obviously launch costs have to come down to something like what's physically possible, not a minor change from what's going on today. Total propellant costs are around $10/pound of payload, and at an airline-like fuel to price ratio, we should eventually be talking about $40/pound. For 10,000 tons that's 20,000,000 pounds and $800,000,000 dollars. Which is actually pretty good for a low-maintenance, low-pollution, grid-quality power source.

Don't get me wrong, I think doing this within the next few years is silly. It just doesn't work with current launch costs. But I think it's pretty viable for the second half of this century, and if global warming turns out to be a real concern it will probably make up a big part of the solution.

I think it's viable launching from earth with only modestly favorable technological assumptions over 50-100 years. It's a slam-dunk if cheap space-sourced materials become available. It's not like we're talking about a really complicated machine here. It's big, yes, but not complicated.

Oh, the beam really isn't all that dangerous:

Of course, if the beam is that weak, why are we bothering?

"If we’re going to wait for a full space-based manufacturing facility ... at least 100 years from now."

No one really knows how long it will take but 100 years seems unrealistically long. In the previous 60 years humans have put literally thousands of objects into space and the cost is going down and the capability of what we do put up has been steadily going up. I'd be surprised if the Earth doesn't have a significant space industry by 2065.

"So in the end I’m not sure you’ve gained a whole lot in terms of efficiency over just building a solar plant on Earth, but your costs are orders of magnitude higher. If you had to launch all this stuff from Earth, you’d be looking at maybe $100 billion in launch costs alone."

You don't launch a power plant for beaming power back to Earth. I doubt that will ever be economical. You launch the infrastructure to build the components from the raw materials on the Moon and/ or the asteroid belt. Once you have the infrastructure, the cost to run the manufacturing facilities is trivial. Most of the workers will be semi-autonomous teleoperated robots. And indeed, you might not build solar cells at all. Instead you might create a nuclear plant and beam down the power from them.

Granted, none of this is guaranteed. We very well might discover cheap, efficient fusion power in the next 20 years and make space to Earth power production needless. However, we will build a space based manufacturing industry. Space is the next frontier. Vast sums will be spent to open up space, but billionaires are already lining up to spend their money on the idea.

Fusion could undercut it, but space-based solar is vastly more ready for primetime. We could build space-based solar power today, and it would work just fine. It would just be really expensive.

As a reminder: It's been 46 years since Apollo 11. It's been 40 years since the Space Shuttle first flew. After all that time, NASA today doesn't even have a manned space launch ability, and estimates of how long it would take even to go back to the moon say it will take longer than it took the original Apollo program from when Kennedy made the commitment to go to the moon in 1961.

The only reason I say 100 years is possible is because I hope private space will accelerate things. If we left it up to NASA, we wouldn't be anywhere near the point where we could do this in 100 years. That agency is moving at a glacial pace now when it comes to manned spaceflight and heavy lift. NASA was supposed to have a manned launcher ready a couple of years after retirement of the Shuttle. They're now talking about the first manned flight of the Orion capsule 'as early as' 2021 - 11 years after the shuttle was retired.

It's not hard to see why this will take a long time if you think about what needs to happen. If we need to build this thing in space (and we would, or it will be a non-starter financially), then we need to be able to:

1. develop the capability to fly out to where the resources are (asteroids, moon, whatever).
2. Develop a vehicle that can cost-effectively move that material into GEO.
3. Bring back samples and develop techniques for working with them in space.
4. Build and test manufacturing facilities that can work in space.
5. Launch those facilities.
6. Build a huge, complex power station from scratch in space using space-sourced materials.
7. Build a 10km antenna array on earth.

Each one of those steps is going to take many years. NASA says they are planning an asteroid sample return mission that will fly as early as 2025. Given NASA's recent record, I'd say 2030, but more likely it will be cancelled. But let's say they fly it. There goes 10 years before we even get an asteroid sample.

If they immediately began planning a vehicle that could move large masses from asteroids to GEO, that design would likely take a decade or more before the thing was tested and operational. And that's being generous. Now you're 20-30 years out, and you've barely even started on the major work.

Now you have to figure out how to extract the materials from an asteroid, and that's likely a multi-decade affair. Asteroids are a long way away - each trip out there has to be planned on a multi-year window. The stuff out there has to work perfectly. If you're sending humans, you also have the problems of radiation shielding and logistics - food, water, etc. The asteroids are farther than Mars.

And don't forget, it still costs delta-V to move the mass from the asteroid belt to Earth, so you're going to need a lot of fuel. So even if the mass for the solar power station comes from space, the mass in fuel to move that material will initially be coming from Earth. So we're still talking about a lot of rocket launches.

And there's still so much we don't even know. Microwave power beaming hasn't even been tried outside of short distance scale experiments. We have no idea how to do manufacturing in space, and will have to laboriously prove out various techniques. And so it goes.

This is the problem with engineering projects that have many dependencies and precursor requirements, especially in an environment where each iteration takes years or decades. We're used to rapid change because semiconductors have been advancing rapidly. But when it comes to physical engineering of large-scale structures, we're much slower at building them now than we used to be. In the time it took to build the Hoover Dam you couldn't even get through the environmental impact statements and legal challenges today. A single nuclear plant takes more than a decade to build.

"Launch costs only need to drop low enough to create a space based industry. It will probably be more expensive to launch the solar cells directly from the Earth than it will be to mine the materials from the asteroids and build them directly in space. At least for a significant area of solar cells."

If we're going to wait for a full space-based manufacturing facility that can make the cells and all the hardware required for them cost effectively (including amortizing the costs of lifting up all the manufacturing and mining equipment in the first place), we're talking about a very distant future - at least 100 years from now. By then, we may have figured out better power sources anyway.

And even then, it's hard to imagine that you could build these things for anywhere near the cost of building them on Earth. We're talking about thousands of tons of materials for a gigawatt-sized solar power station. Even the cost of moving that stuff around in space will not be insignificant.

"More than likely there’s no loss from going through vacuum. So, the difference in beaming the power through 600 miles of atmosphere vs 23,400 miles of vacuum + 600 miles of atmosphere is negligible. And beam dispersion probably doesn’t matter, since most of the plans I’ve seen assumed that you would use a very wide collector on Earth in any case, just for safety."

If we assume microwave beaming, then from geostationary orbit you need truly huge collectors and truly huge transmission antennas. There is significant beam spread in those frequencies over that distance. NASA's study indicated a need for a 1km diameter transmission antenna and a 10km diameter receiving antenna in order to beam 2.45 GHz microwave power back to earth. The 10:1 spread in size is to avoid beam spread losses.

Let's talk about losses: You lose energy going through the Earth's atmosphere. You lose energy converting the solar power to microwave energy. You lose some energy from beam spread (hopefully not much). You lose more if weather conditions are bad - lots of precipitation or humidity absorbing microwave energy. You are then losing more energy converting the microwave power back into electrical energy. NASA estimates the DC-to-DC energy losses at just over 60%. Then, assuming you have to locate your giant 10KM receiving antenna far from any valuable land, you have transmission line losses to consider.

All of this to gain what? 24 hour power capability and more powerful direct sunlight, but you can only use 47% of that power due to losses, so are you really gaining enough in efficiency to warrant doing all this in space?

So in the end I'm not sure you've gained a whole lot in terms of efficiency over just building a solar plant on Earth, but your costs are orders of magnitude higher. If you had to launch all this stuff from Earth, you'd be looking at maybe $100 billion in launch costs alone.

And just how environmentally friendly do you think this plant will be? You are expending a lot of energy lifting mass into orbit, you're using up a 10km circle of land somewhere (and disrupting the wildlife around it), and you'll be beaming gigawatts of power through the atmosphere constantly. That may be harmless or it may not be, but do you really think environmentalists aren't going to worry about that?

In comparison, a 4GW nuclear power plant takes up a few acres and can be built for less than $10 billion. It provides high quality baseload power 24/7.

I'm as big a supporter of space as you're likely to find, and I wish these satellites made more sense as they could really jump-start a large commercial space program. But I just don't see it. I put these power satellites in the same category as space elevators and colonizing Mars: interesting thought experiments and a tantalizing glimpse at the distant future, but not something that's going to help solve our energy problems in my lifetime or probably even my kid's lifetime.

This is not the technology to jump-start space development, and that's where all your calculations go wrong. This isn't viable until we're well down the cost curve. Adding up Falcons just isn't going to work. It's like pricing New York-London tickets based on the economics of the Wright Flyer.

I understand that. Which is why this is a long, long way into the future.

I actually wrote my Master's thesis on this topic, and published the condensed version as a chapter in a book on the Energy Crisis: “Miracle in the Sky: Solar Power Satellites,” in _American Energy Policy in the 1970s_, edited by Robert Lifset (Norman: University of Oklahoma Press, 2014).

The short version is that some version of this story has been running approximately every 6-9 months since, well, the '70s. And the stories from the '80s and '90s read pretty much just like this one. It might well be the future, but I wouldn't buy stock yet.

Amazon book link:

Take a circle, measure the circumference, measure the diameter, pi is in there somewhere . . . wonderful number . . .

this is heaven folks . . . those of you who want to make it hell? . . . that's the norm, the average, the 2b expected . . .

until the next quasar takes us out . . .

dear lil f o f faces . . . listen up

we is here, 4u, 2day . . .

dear lil poopie shits . . . "

#3. On the wrestlers, it seems that for some people the more access to goods and services they have the earlier they die. there was a story that Cubans lived longer since food has gotten scarcer.

Why is retirement bad for males’ health?
A second channel suggests that changes in health-related behaviours associated with smoking, drinking, an unhealthy diet, and little physical exercise may cause premature death following early retirement. Our results strongly support this hypothesis. Complementary data from cause-of-death statistics reveal that excess mortality is concentrated on three causes of deaths:
(i) ischemic heart diseases (mostly heart attacks),

(ii) diseases related to excessive alcohol consumption, and

(iii) vehicle injuries.

Work gives structure to life.

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