GaN-based LED's have only been commercially available since 1994, and only recently at a reasonable efficiency and price. Using LED's is quite different from using tungsten filament or gas discharge lamps (aka flourescent lamps).
As mentioned previously in these comments, plants only absorb a small fraction of the solar irradiation. For example, chlorophyll, the dye molecule used by many plants, only absorbs significantly in relatively narrow bands of the blue and red, corresponding to 2% of the total solar irradiant power.
It turns out that the bandwidth of these absorption peaks matches quite closely with the bandwidths of blue and red LED's operating near room temperature. Thus, even with 20% efficient LEDs the total power-to-plant-product efficiency can likely approach 100%. If you replace the plants with standard 18% efficient solar cells, you could feasibly have several layers of plants powered by the same footprint, although at a greatly increased capital cost.
If you add in the improved control over germination and growth afforded by an enclosed and highly-regulated environment, the economics might begin to make sense, especially considering the long lifetime of color-pure LED's (much longer than phosphor-converted LED's).
Almost all of the pictures look like purple + red to me. There's one picture that looks like it has a fraction of white lights. However, most LED white lights are actually blue/uv + yellow.
Thus, you seem to be jumping to conclusions. If anything, you're point about plants only being able to use 1% of the power from sunlight suggests that they might be on to something.
What ultimately matters here is economics. There is obviously a huge capital cost involved here, but it very well may be merited, especially for growing delicate species. And the more these systems are utilized, the more economy of scale will make it economical for more general applications.
I am a bit put off by the lack of costs in the article, but I guess that is to be expected from a press release. Since this is still in research stages, it is almost certainly not yet economical. However, if it is even within a factor of 10x of breakeven over a ~20 year time frame (including capital costs, but replacing the researchers' salaries with technicians'), then this could be a significant player in the future.
I agree that super-conductor based magnetic levitation systems have questionable economics, at least with the current state of high-temperature superconductors. However, that hasn't prevented Maglev train test-tracks from being built.
In contrast, standard active magnetic levitation bearings are very economically viable, particularly in applications requiring extremely high rotational speeds, long operating times, and low oil contamination, e.g. turbomolecular vacuum pumps.
The project looks interesting from an academic perspective, but the stated application to biological microfluidics seems ridiculous when it requires the droplets to be filled with magnetic materials that could potentially compromise any test you might want to perform.
Microfluidic channels are fairly easy to produce using traditional lithography, and a simple water pump produces all of the motion necessary. It's difficult to see how this really improves upon that model.
Fairness is irrelevant. If you make it illegal to do security probes, many of the white hats will just go black hat. There's no way to effectively regulate it.
Or you can start a "war on hackers", which will be even less effective than the other ill-defined wars.
That would be incredible if increasing the pressure caused water to boil. I think there's a perpetual motion machine in there somewhere.
(Lowering the pressure could cause water to boil, but not increasing it. Maybe you meant the heat from friction, but I doubt there's that much heat being generated.)
It's already been shown that the SpaceX design can get within 105m of a landing pad. If it ends up being too difficult to finish the landing as is, adding more landing site sensors to improve prediction, and adding a catching mechanism should solve the problem. And note that all of these additions are one-time costs that don't have to be lifted to 100km. My money works definitely be on the spacex design.
I would actually love to see more research being done shopping these lines. The complete failure of biosphere as a self-sustained ecosystem shows we have a lot to learn before independent colonies become realistic.
It's a phenomenon I call delusional optimism. People see the exponential growth that the semiconductor industry experienced for most of their life, and assume it's typical. Exponential growth in a finite world is transient. The generation just now being born won't be so delusionally optimistic.
You seem to know a good amount about the design of rocket systems. I have a question for you. If reentry is so difficult, why not split stages earlier, before it becomes such a challenge? Aren't the currently used stage timings optimized assuming no reuse? What if you optimize for cost, and assume first stage recovery, but require a more manageable (earlier) split?
Slight correction: Edison settled on carbonized bamboo filament (and he wasn't the first to use a carbon filament). The tungsten filament lamp came several years later, and not from Edison.
And what makes you think that squishing two AI brains would give you twice the intelligence? About the only thing we can reasonably say about a working implementation of general AI is that it must be closer to an animal brain than a silicon processor. Look at sperm whales. Their brains are 5x more massive brains than humans, and yet no one would say they are 5x more intelligent.
You cannot borrow money into existence AT ZERO COST and loan it out WITH COMPOUNDING INTEREST into perpetuity without eventually having to deal with the reality that trees don't grow to the sky.
You're missing the forest for the trees. Even without a central bank this would still happen with regular banks. Even with a commodity-backed currency this would still happen with regular banks.
There's nothing inherently wrong with the creation of capital through lending. The problem is that too much leverage results in speculation and Ponzi schemes. The dose makes the poison.
I'm not so sure it's different. There are still far too many companies, with advertising as their only source of income, valued at billions of dollars.
You can't buy shares of Dropbox because it has not gone public yet. It will. Almost all of these highly-valued internet companies go public, because they were funded by VC's who expect a large, quick payoff.
Slashdot Mirror
But then you're just slowing the market. When possible, it's better to dampen oscillations/overshoots than to reduce ramp rates.
GaN-based LED's have only been commercially available since 1994, and only recently at a reasonable efficiency and price. Using LED's is quite different from using tungsten filament or gas discharge lamps (aka flourescent lamps).
As mentioned previously in these comments, plants only absorb a small fraction of the solar irradiation. For example, chlorophyll, the dye molecule used by many plants, only absorbs significantly in relatively narrow bands of the blue and red, corresponding to 2% of the total solar irradiant power.
It turns out that the bandwidth of these absorption peaks matches quite closely with the bandwidths of blue and red LED's operating near room temperature. Thus, even with 20% efficient LEDs the total power-to-plant-product efficiency can likely approach 100%. If you replace the plants with standard 18% efficient solar cells, you could feasibly have several layers of plants powered by the same footprint, although at a greatly increased capital cost.
If you add in the improved control over germination and growth afforded by an enclosed and highly-regulated environment, the economics might begin to make sense, especially considering the long lifetime of color-pure LED's (much longer than phosphor-converted LED's).
Almost all of the pictures look like purple + red to me. There's one picture that looks like it has a fraction of white lights. However, most LED white lights are actually blue/uv + yellow.
Thus, you seem to be jumping to conclusions. If anything, you're point about plants only being able to use 1% of the power from sunlight suggests that they might be on to something.
Parent deserves to be modded up.
What ultimately matters here is economics. There is obviously a huge capital cost involved here, but it very well may be merited, especially for growing delicate species. And the more these systems are utilized, the more economy of scale will make it economical for more general applications.
I am a bit put off by the lack of costs in the article, but I guess that is to be expected from a press release. Since this is still in research stages, it is almost certainly not yet economical. However, if it is even within a factor of 10x of breakeven over a ~20 year time frame (including capital costs, but replacing the researchers' salaries with technicians'), then this could be a significant player in the future.
If/when the price of jet fuel is 10-100x higher (which will admittedly be a long time from now), high-speed rail will make a comeback.
I agree that super-conductor based magnetic levitation systems have questionable economics, at least with the current state of high-temperature superconductors. However, that hasn't prevented Maglev train test-tracks from being built.
In contrast, standard active magnetic levitation bearings are very economically viable, particularly in applications requiring extremely high rotational speeds, long operating times, and low oil contamination, e.g. turbomolecular vacuum pumps.
Unfortunately that's not the case. Homeopathic remedies often do have content other than water, but in uncontrolled and untested doses, sometimes resulting in dangerous effects. See Zicam nose spray, for example. The FDA finally stepped in after hundreds or thousands of people lost there senses of smell and taste.
Not to mention that Pu238, the isotope used RTG's is not fissile and cannot be used to make bombs.
Unless massive population migrations and world-wide famines spark a nuclear war...
The project looks interesting from an academic perspective, but the stated application to biological microfluidics seems ridiculous when it requires the droplets to be filled with magnetic materials that could potentially compromise any test you might want to perform.
Microfluidic channels are fairly easy to produce using traditional lithography, and a simple water pump produces all of the motion necessary. It's difficult to see how this really improves upon that model.
Fairness is irrelevant. If you make it illegal to do security probes, many of the white hats will just go black hat. There's no way to effectively regulate it.
Or you can start a "war on hackers", which will be even less effective than the other ill-defined wars.
Unfortunately, the discovery of buzzword reserves has not yet peaked, so we're still at least 30 years off from Peak Buzzword.
That would be incredible if increasing the pressure caused water to boil. I think there's a perpetual motion machine in there somewhere.
(Lowering the pressure could cause water to boil, but not increasing it. Maybe you meant the heat from friction, but I doubt there's that much heat being generated.)
Note, though, that spacex is using payed-for launches to test its recovery system. Thus, the development costs are much lower than they could be.
*15m, not 105m
It's already been shown that the SpaceX design can get within 105m of a landing pad. If it ends up being too difficult to finish the landing as is, adding more landing site sensors to improve prediction, and adding a catching mechanism should solve the problem. And note that all of these additions are one-time costs that don't have to be lifted to 100km. My money works definitely be on the spacex design.
Sorry, I'm on my phone. "Shopping those lines" was supposed to be "along those lines".
I would actually love to see more research being done shopping these lines. The complete failure of biosphere as a self-sustained ecosystem shows we have a lot to learn before independent colonies become realistic.
It's a phenomenon I call delusional optimism. People see the exponential growth that the semiconductor industry experienced for most of their life, and assume it's typical. Exponential growth in a finite world is transient. The generation just now being born won't be so delusionally optimistic.
You seem to know a good amount about the design of rocket systems. I have a question for you. If reentry is so difficult, why not split stages earlier, before it becomes such a challenge? Aren't the currently used stage timings optimized assuming no reuse? What if you optimize for cost, and assume first stage recovery, but require a more manageable (earlier) split?
Slight correction: Edison settled on carbonized bamboo filament (and he wasn't the first to use a carbon filament). The tungsten filament lamp came several years later, and not from Edison.
And what makes you think that squishing two AI brains would give you twice the intelligence? About the only thing we can reasonably say about a working implementation of general AI is that it must be closer to an animal brain than a silicon processor. Look at sperm whales. Their brains are 5x more massive brains than humans, and yet no one would say they are 5x more intelligent.
3D interconnects? You mean like the ones that have been in chips for decades?
Transistors are not neurons. They don't process like neurons, and they aren't plastic like neurons.
You cannot borrow money into existence AT ZERO COST and loan it out WITH COMPOUNDING INTEREST into perpetuity without eventually having to deal with the reality that trees don't grow to the sky.
You're missing the forest for the trees. Even without a central bank this would still happen with regular banks. Even with a commodity-backed currency this would still happen with regular banks.
There's nothing inherently wrong with the creation of capital through lending. The problem is that too much leverage results in speculation and Ponzi schemes. The dose makes the poison.
I'm not so sure it's different. There are still far too many companies, with advertising as their only source of income, valued at billions of dollars.
You can't buy shares of Dropbox because it has not gone public yet. It will. Almost all of these highly-valued internet companies go public, because they were funded by VC's who expect a large, quick payoff.