Speaking of product lifetimes... I'd like to see at least some transparency, and maybe some consumer control, in rechargeable battery management. As I understand it, rapid charging, charging to nearly full capacity, and discharging to near empty, all shorten the life of a lithium-ion battery. I would like to know whether a product is designed for 100 cycles, or 1000, or what. I don't see that in product spec sheets. If anything, they brag about quick charging and long intervals between charges. Does it stop charging at 80% of capacity, and start warning me when it discharges to 20%? If the charge state is only indicated by a 5 bar display, do those bars indicate the full charge range, or only the part between 10% and 90% (like the gas gauge in a car)? Does the number of cycles depend on whether I use the charger that came with the device?
Ideally, I'd also like some control over battery management - e.g., only charge my smartphone up to 80% unless I'll be taking a long flight the next day.
The energy required to lift a spacecraft to 100 km altitude is about hg=100 km*10 m/ s^2=10^6 J/kg. for orbital velocity you need an additional 1/2 (7 km/s)^2 = 26*10^6 J/kg. So maybe the SpaceX problem was 27 times harder. Except we should be multiplying by the mass of the payload. What was the payload for the Blue Origin demo flight?
For a while, customers will pay extra for a brand new booster. Eventually, SpaceX will have to offer a discount to persuade customers to trust their payload to a rocket on its maiden flight.
I agree 97%. Nuclear fission is the right solution for grid electricity at least for the next 50 years. But there is more to the energy story than grid electricity. Molten salt reactors can also provide a lot of the necessary process heat (unlike the water cooled reactors which are restricted to lower temperatures). (It might be easier to fund development of those reactors if it isn't necessary to also buy the turbines and generators for producing electricity. At least that's how Terrestrial Energy proposes to attack the problem.) I believe synfuels can be produced more efficiently using process heat rather than electricity. Once that infrastructure is in place, it might be better to produce more synfuels instead of replacing our inventory of cars and trucks with electric vehicles and adding enough grid capacity to keep them charged.
Small Modular Reactors have advantages even if they don't get sold to every village. If they're small enough to build on an assembly line and ship where needed, you can get big improvements in cost and reliability. A utility doesn't have to pay for a 6GW power plant all at once, but can instead install a smaller unit, and let it generate revenue while further units are under construction. It can also adjust the construction rate if the demand growth doesn't match predictions.
(That said, I would still like to see most military bases powered and heated by their own nuclear reactors.)
No, the rotating space station should be much cheaper. Note that it does not have to be a big doughnut as in "2001" - we could just separate the nuclear reactor from the manned part, connect them with a cable, and set them to rotating. Any deep space transit craft should be set up the same way (except there you'll have nice heavy fuel tanks for the counterweight), so the astronauts arrive healthy.
You may find it convenient to get part of your power from solar panels, but it does entail a big capital investment. The batteries or grid-connected power for night time power would be another big capital investment. Currently many of the power companies are using gas-fired generators to minimize that investment (and to enable them to ramp up quickly when solar or wind power suddenly drops). You suggest backing up the solar with nuclear, and that can work. However, the current generation of nuclear power requires an even bigger investment in capital. Few owners want to let any significant amount of its capacity go unused. I think the ideal approach is to (1) invest today in enough research that the next generation of nuclear power (e.g., LFTR) will be much less expensive, (2) also invest in battery technology for grid-connected storage, (3) put a price on carbon dioxide emissions, (4) let the price of electricity float during the day, and (5) let the market decide what combination of solar panels, extra nuclear capacity, and grid-connected storage makes the most sense.
The real fantasy is that the 600M people in India without electricity could rely on solar power. They do not have the land or the money to invest that way.
"Time spent with eyes focused on close objects (such as reading or computering) = myopia." RIGHT.
How it's supposed to work: Child is born farsighted -> much time spent outside looking at distant objects, but focusing muscles in the eye can still bring those objects into focus -> muscles get tired -> brain concludes "I'm still farsighted" -> eyes grow -> eyes can relax most of the time - i.e. while looking at distant objects = perfect vision.
How it's working in industrialized countries: Much time spent with eyes focused on close objects -> focusing muscles in the eyes get tired -> brain concludes "I'm still farsighted" -> eyes grow -> eyes can relax most of the time - i.e. while looking at CLOSE objects = myopia. If you get glasses that "correct" for myopia, and wear them while reading, then you go around the loop again and the myopia gets worse. That's what happened to me - I need a correction of -4 diopters or so.
Lesson #1: if you have myopia, so you need glasses for distant work, then take those glasses off if you're doing a lot of close work. Or else get bifocals.
Lesson #2: To prevent myopia in the first place, get kids to wear READING GLASSES (+1.5 or +2 diopters) while doing a lot of close work. That way their eyes are focused at infinity (therefore relaxed) even though they're doing close work. My daughter was willing to do this, because it was only while she was at home working on the computer or reading, and not when she was out with other kids. She graduated as an engineer, and still doesn't need glasses.
...in decreasing utility far as the patient is concerned. Unfortunately, as far as the medical-industrial complex is concerned, "expensive treatment for the duration of the patent" is the primary goal, with cures and vaccinations to be avoided if possible. We'll be stuck with that as long as medical research is paid for out of drug company profits. If, on the other hand, we had a "single payer" health care system, the federal government would have an incentive to fund research into cures and prevention.
Didn't I read that the entire German windmill farm doesn't generate as much power as Vermont Yankee, all by itself?
The "business case" for wind power includes a lot of government mandates.
The notion that pumping water underground causes earthquakes has been around quite a while. What bothers me is the knee-jerk reaction that this is necessarily a bad thing. The choice is not between an earthquake or no earthquake. Rather, it's between an earthquake now, or a bigger earthquake later. Remember that the energy of the earthquake comes from strain in the rocks, which in general is continually building (due to shifting tectonic plates, moving magma, etc.). If it's not released now, then the strain will just build until it's released later - and you get a bigger earthquake.
I will grant there might be a few cases where I'd rather reduce the chances of an earthquake in the short term, even if it made the eventual earthquake worse (say, if I just discovered a weakness in a dam, and will be spending the next two years madly strengthening it). But in general I would rather have more, smaller earthquakes.
Li-ion batteries in laptops and cell phones don't last long, but for automotive use they're using a different electrode (lithium manganese oxide instead of lithium cobalt oxide - see http://www.technologyreview.com/printer_friendly_article.aspx?id=26832) which they think will last a lot longer. I'd like to know when I can get the longer-lasting kind for my laptop. Or would they rather design in a short product life?
There should be radiation, but not necessarily neutrons. I'd be very interested in a gamma spectrum from this device. That should tell us which nuclear reactions are taking place, though not necessarily why (e.g. how the catalyst works).
I've long heard about people with a compulsion to eat dirt - ascribed to a mineral deficiency. Maybe a bacteria deficiency instead, or in addition? (It's somewhat easier to contemplate than a "fecal transplant", anyway.)
I recommend you find a copy of "The 24 Hour Society" by Martin Moore-Ede and read closely about the nine factors that determine alertness. Then design for them. For example:
Refuse to install "subdued lighting", no matter how cool your manager thinks it looks. If somebody complains about washed-out displays, then install brighter displays.
Put the processors outside the control room if possible. A steady drone tends to put people to sleep, and it's hard to talk over.
Set the temperature a little on the cool side.
Another poster wanted restrooms on the same level. I'd say they should certainly be handicapped accessible, but for most of us climbing a flight of stairs now and then is a good way to wake up.
If there's a possibility of a crisis that will call for flat-out effort for days on end, I'd suggest:
A place to crash, with cots and showers. It turns out people can get by on only two or three hours/day of sleep, if it's in the form of 20 to 30 minute naps every four hours. (That's in Moore-Ede's book, too.)
Yes, the real issue is false positives. If there's a reward for valid warnings but no penalty for false positives, then somebody will automate the process and submit 1e6 warnings. Per second. And the SEC will learn VERY QUICKLY to ignore all of them.
In fact, I wonder how many false positives the SEC already gets. I expect that's a major reason whistle blowers already get ignored.
Also if the file is still there, you can use a program to "search for similar contents" to find the copies you didn't know the OS made: previous versions, web cache, daily backup, swap, hibernation files...
The altitude is important too. The lifetime of a circular orbit varies approximately as the seventh power of the altitude. That means the junk from the accidental collision of Feb 2009 (789 km altitude) and the Chinese test of Jan 2007 (537 km) will stay up a lot longer than that from the U.S. spy satellite shoot-down of Feb 2008 (247 km). Why couldn't the Chinese have picked a lower-altitude target?
About that aerogel: Assuming LEO spans 1000 km, we have a volume of something like pi*6378^2*1000 ~ 1e11 km^2 to clean up. Assume we put a one-km cube of aerogel into a retrograde orbit*, so its velocity with respect to the junk averages 10 km/s. The time it would take to sweep the volume would be 1e11/10=1e10 s, or about 300 years. Like mopping 30 hectares, or 80 acres, with that cotton swab.
* or many smaller blobs, in a variety of orbits, with an effective cross section of 1 km^2. Each blob has to be thick enough to stop or de-orbit the biggest piece of junk you're worried about.
Their plan is to launch a vehicle with its own maneuver capability. It's needed to circularize the orbit and to rendezvous. Mainly, they plan to launch fuel. Then a probe with just enough delta V to get into low earth orbit can refuel and continue into deep space.
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"If it floats it's food" is a rule that's worked well for a very long time. Maybe longer than photosynthesis.
Speaking of product lifetimes... I'd like to see at least some transparency, and maybe some consumer control, in rechargeable battery management. As I understand it, rapid charging, charging to nearly full capacity, and discharging to near empty, all shorten the life of a lithium-ion battery. I would like to know whether a product is designed for 100 cycles, or 1000, or what. I don't see that in product spec sheets. If anything, they brag about quick charging and long intervals between charges. Does it stop charging at 80% of capacity, and start warning me when it discharges to 20%? If the charge state is only indicated by a 5 bar display, do those bars indicate the full charge range, or only the part between 10% and 90% (like the gas gauge in a car)? Does the number of cycles depend on whether I use the charger that came with the device?
Ideally, I'd also like some control over battery management - e.g., only charge my smartphone up to 80% unless I'll be taking a long flight the next day.
The energy required to lift a spacecraft to 100 km altitude is about hg=100 km*10 m/ s^2=10^6 J/kg. for orbital velocity you need an additional 1/2 (7 km/s)^2 = 26*10^6 J/kg. So maybe the SpaceX problem was 27 times harder. Except we should be multiplying by the mass of the payload. What was the payload for the Blue Origin demo flight?
For a while, customers will pay extra for a brand new booster. Eventually, SpaceX will have to offer a discount to persuade customers to trust their payload to a rocket on its maiden flight.
The British were building warships with aluminum superstructures to save weight, but lost one to a fire during the Falkland Islands war.
I agree 97%. Nuclear fission is the right solution for grid electricity at least for the next 50 years. But there is more to the energy story than grid electricity. Molten salt reactors can also provide a lot of the necessary process heat (unlike the water cooled reactors which are restricted to lower temperatures). (It might be easier to fund development of those reactors if it isn't necessary to also buy the turbines and generators for producing electricity. At least that's how Terrestrial Energy proposes to attack the problem.) I believe synfuels can be produced more efficiently using process heat rather than electricity. Once that infrastructure is in place, it might be better to produce more synfuels instead of replacing our inventory of cars and trucks with electric vehicles and adding enough grid capacity to keep them charged.
Small Modular Reactors have advantages even if they don't get sold to every village. If they're small enough to build on an assembly line and ship where needed, you can get big improvements in cost and reliability. A utility doesn't have to pay for a 6GW power plant all at once, but can instead install a smaller unit, and let it generate revenue while further units are under construction. It can also adjust the construction rate if the demand growth doesn't match predictions. (That said, I would still like to see most military bases powered and heated by their own nuclear reactors.)
No, the rotating space station should be much cheaper. Note that it does not have to be a big doughnut as in "2001" - we could just separate the nuclear reactor from the manned part, connect them with a cable, and set them to rotating. Any deep space transit craft should be set up the same way (except there you'll have nice heavy fuel tanks for the counterweight), so the astronauts arrive healthy.
7.5) Make enough Pu 238 to power the RTG.
You may find it convenient to get part of your power from solar panels, but it does entail a big capital investment. The batteries or grid-connected power for night time power would be another big capital investment. Currently many of the power companies are using gas-fired generators to minimize that investment (and to enable them to ramp up quickly when solar or wind power suddenly drops). You suggest backing up the solar with nuclear, and that can work. However, the current generation of nuclear power requires an even bigger investment in capital. Few owners want to let any significant amount of its capacity go unused. I think the ideal approach is to (1) invest today in enough research that the next generation of nuclear power (e.g., LFTR) will be much less expensive, (2) also invest in battery technology for grid-connected storage, (3) put a price on carbon dioxide emissions, (4) let the price of electricity float during the day, and (5) let the market decide what combination of solar panels, extra nuclear capacity, and grid-connected storage makes the most sense.
The real fantasy is that the 600M people in India without electricity could rely on solar power. They do not have the land or the money to invest that way.
"Time spent with eyes focused on close objects (such as reading or computering) = myopia." RIGHT.
How it's supposed to work: Child is born farsighted -> much time spent outside looking at distant objects, but focusing muscles in the eye can still bring those objects into focus -> muscles get tired -> brain concludes "I'm still farsighted" -> eyes grow -> eyes can relax most of the time - i.e. while looking at distant objects = perfect vision.
How it's working in industrialized countries: Much time spent with eyes focused on close objects -> focusing muscles in the eyes get tired -> brain concludes "I'm still farsighted" -> eyes grow -> eyes can relax most of the time - i.e. while looking at CLOSE objects = myopia. If you get glasses that "correct" for myopia, and wear them while reading, then you go around the loop again and the myopia gets worse. That's what happened to me - I need a correction of -4 diopters or so.
Lesson #1: if you have myopia, so you need glasses for distant work, then take those glasses off if you're doing a lot of close work. Or else get bifocals.
Lesson #2: To prevent myopia in the first place, get kids to wear READING GLASSES (+1.5 or +2 diopters) while doing a lot of close work. That way their eyes are focused at infinity (therefore relaxed) even though they're doing close work. My daughter was willing to do this, because it was only while she was at home working on the computer or reading, and not when she was out with other kids. She graduated as an engineer, and still doesn't need glasses.
...in decreasing utility far as the patient is concerned. Unfortunately, as far as the medical-industrial complex is concerned, "expensive treatment for the duration of the patent" is the primary goal, with cures and vaccinations to be avoided if possible. We'll be stuck with that as long as medical research is paid for out of drug company profits. If, on the other hand, we had a "single payer" health care system, the federal government would have an incentive to fund research into cures and prevention.
...and how much stays with that country's dictator and his family?
Didn't I read that the entire German windmill farm doesn't generate as much power as Vermont Yankee, all by itself? The "business case" for wind power includes a lot of government mandates.
I will grant there might be a few cases where I'd rather reduce the chances of an earthquake in the short term, even if it made the eventual earthquake worse (say, if I just discovered a weakness in a dam, and will be spending the next two years madly strengthening it). But in general I would rather have more, smaller earthquakes.
Li-ion batteries in laptops and cell phones don't last long, but for automotive use they're using a different electrode (lithium manganese oxide instead of lithium cobalt oxide - see http://www.technologyreview.com/printer_friendly_article.aspx?id=26832) which they think will last a lot longer. I'd like to know when I can get the longer-lasting kind for my laptop. Or would they rather design in a short product life?
There should be radiation, but not necessarily neutrons. I'd be very interested in a gamma spectrum from this device. That should tell us which nuclear reactions are taking place, though not necessarily why (e.g. how the catalyst works).
How about: "millions for security, but not one cent for theater!"
I've long heard about people with a compulsion to eat dirt - ascribed to a mineral deficiency. Maybe a bacteria deficiency instead, or in addition? (It's somewhat easier to contemplate than a "fecal transplant", anyway.)
Why doesn't this bill apply to streaming video services like hulu? Their commercials are a lot louder than anything I've heard on TV broadcasts.
If there's a possibility of a crisis that will call for flat-out effort for days on end, I'd suggest:
Yes, the real issue is false positives. If there's a reward for valid warnings but no penalty for false positives, then somebody will automate the process and submit 1e6 warnings. Per second. And the SEC will learn VERY QUICKLY to ignore all of them. In fact, I wonder how many false positives the SEC already gets. I expect that's a major reason whistle blowers already get ignored.
Also if the file is still there, you can use a program to "search for similar contents" to find the copies you didn't know the OS made: previous versions, web cache, daily backup, swap, hibernation files...
The altitude is important too. The lifetime of a circular orbit varies approximately as the seventh power of the altitude. That means the junk from the accidental collision of Feb 2009 (789 km altitude) and the Chinese test of Jan 2007 (537 km) will stay up a lot longer than that from the U.S. spy satellite shoot-down of Feb 2008 (247 km). Why couldn't the Chinese have picked a lower-altitude target?
* or many smaller blobs, in a variety of orbits, with an effective cross section of 1 km^2. Each blob has to be thick enough to stop or de-orbit the biggest piece of junk you're worried about.
Their plan is to launch a vehicle with its own maneuver capability. It's needed to circularize the orbit and to rendezvous. Mainly, they plan to launch fuel. Then a probe with just enough delta V to get into low earth orbit can refuel and continue into deep space.