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Study: Past Climate Change Was Caused by Ocean, Not Just the Atmosphere

DanielRavenNest Obvious to Engineers (185 comments)

Any engineer who has studied thermodynamics knows that water has about four times the specific heat as air. The mass of the oceans is about 260 times that of the atmosphere. Combine these facts, and you find the oceans have about 1000 times the heat capacity of the atmosphere. Thus it should be obvious that in any scenario of temperature change, the oceans will play a big, if not dominant part.

In regards to Chipmunk100's summary, greenhouse gases affect the heat input to the planet. The oceans represent a vast amount of thermal storage capacity. One is the current rate of change, the other is the integrated total of the changes over a number of centuries. Different units with different dimensions. A change in greenhouse gases today will take a long time to show up as an overall change in ocean temperature.

5 days ago
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Solar Could Lead In Power Production By 2050

DanielRavenNest Re:Solar Could be 50+% of production, but... (167 comments)

Areas of the country that are very cloudy tend to have more wind and hydro energy, cause clouds tend to be associated with storm fronts. You are correct that solar varies in usability by location, but typically other renewables compensate. Hydro in Seattle, solar in Phoenix. And grid operators know this. They aren't stupid.

about a month ago
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Solar Could Lead In Power Production By 2050

DanielRavenNest Re:You are generating it from oil, just indirectly (167 comments)

Hey, Mr. Coward, if that's true, why to panel producers put up to 25 year warranties on them? The warranty says they will produce at least 80% of stated power level for that long.

About your use of expletives: Fuck you.

about a month ago
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MIT Study Outlines a 'Perfect' Solar Cell

DanielRavenNest Re:The problem isn't energy effiencey but cost. (110 comments)

Walmart already puts solar panels on many of their stores: http://cdn2.tekgoblinmedia.com...

Besides generating electricity, the panels protect the underlying roof from sun exposure, thus extending their useful life. When they run out of rooftops, they can start on the parking lots. This not only generates more electricity, it provides covered parking. In sunny states this is very desirable. Once electric cars become more popular, charging stations powered by panels above the parking lot will be another desirable feature for customers - shop and recharge your battery at the same time.

about a month ago
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MIT Study Outlines a 'Perfect' Solar Cell

DanielRavenNest Re:Carnot efficiency (110 comments)

> 1) Blackbody radiation is emitted from all sides of the emitter; it cannot be made directional.

Emitter is a cylinder heated from the center. Electricity making cells are a larger cylinder around it. Photons emitted from the inside of the hot cylinder will mostly hit another part of the cylinder.

>2)... This means the emitter has to be bitching hot.

Make the ratio of cylinder sizes large enough, and your electricity making cells won't melt. They will get pretty warm, and you can extract secondary heat by water cooling their back side. Make hot water or something.

about a month ago
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MIT Study Outlines a 'Perfect' Solar Cell

DanielRavenNest Re:Uses blackbody emission (110 comments)

But then I have to ask why not just melt salts and store them so you get energy storage as well.

Because crushed stone is even cheaper than salts or oil for thermal storage. Not much is cheaper than that. You circulate air through a heat exchanger and the rock bed to store heat, and reverse the flow to extract heat. The heat exchanger in turn gets hot fluid from the focus of a solar concentrator. Melty stuff like oil or salts need liquid-tight tanks. A hot rock bed can be a concrete lined ditch filled with rock, but doesn't need to be perfectly air tight, just about as tight as most ventilation systems. A sheet metal lid covered with insulation should be good enough.

about a month ago
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MIT Study Outlines a 'Perfect' Solar Cell

DanielRavenNest Re:perfect? (110 comments)

One producer expect $400/kW in a few years: http://www.pv-tech.org/news/su...

Panel prices are already well into very affordable ranges. As you say, the real work now is getting all the other parts of the cost down (wiring, mounting racks, inverters, labor, land, and paperwork - permits, planning, etc.)

about a month ago
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MIT Study Outlines a 'Perfect' Solar Cell

DanielRavenNest Re:Least helpful summary ever? (110 comments)

Well, going to the abstract of the actual paper, What they have is silicon milled with dielectric cavities (waveguides) that are tuned to the frequency of your solar cell. Hot black bodies can emit any wavelength, but the tuned cavities can only efficiently emit one. Other wavelengths destructively interfere. In that respect they work just like antennas at radio wavelengths.

The tuned light is efficiently absorbed by the solar cell. Natural sunlight isn't because some of the photons are too high in energy, and the excess gets wasted as heat, and some are too low and don't kick out an electron at all. Thus you get around 25% efficiency in a good cell these days.

about a month ago
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Elon Musk: We Must Put a Million People On Mars To Safeguard Humanity

DanielRavenNest Re:Profitable, if self-contradictory (549 comments)

A billion years is of course an extremely long time in the context of human evolution, so who knows what we might be able to accomplish in that timespan.

The world's installed base of solar panels has grown at 55% per year recently. At that rate, we would have enough panels to absorb the entire output of the Sun in less than 80 years. I would revise your statement to read:

"A hundred years is of course an extremely long time in the context of human society, so who knows what we might be able to accomplish in that timespan."

about a month ago
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Elon Musk: We Must Put a Million People On Mars To Safeguard Humanity

DanielRavenNest Re:More Efficient (549 comments)

> I don't know what technology could get a ticket to Mars from the Earth down to say $100 USD,

I do, but then I wrote a textbook about space systems engineering [ http://en.wikibooks.org/wiki/S... ]. It's a combination of self-replicating automation, extracting local materials and energy everywhere, and a space elevator network.

* It would be very expensive to haul all the equipment you need to Mars in order to live there. Instead, what you want to send is a starter kit of basic machines, and use those to build other machines, until you grow big enough to make the final equipment (habitat domes, etc.). You prefer to make this starter kit as automated as possible, since you won't have the facilities to support people until later. You start on Earth, and build a starter kit that grows to a full factory. That factory builds a second starter kit that gets launched to orbit, where it grows to a full factory. In turn that one sends a starter kit to Phobos, and then finally the Phobos one sends one down to Mars.

* All of the factories run off of local solar energy and process local materials to make most of the new products. A few percent will need to be imported parts, because they are too hard to make, or use rare elements. At each location you build up greenhouses, habitat modules, and processing plants. One of the locations is a "Cycling Mars Transfer Orbit", which goes back and forth from Earth to Mars. So instead of sending 10,000 Mars Colonial Transports carrying 100 people each, you build up a mining colony/transit hub that makes multiple trips, carrying people each time.

* A rotating elevator (Skyhook or Rotovator) can provide about as much velocity change as a rocket stage. A series of them in Low Earth Orbit, High Earth Orbit, and Mars Orbit can provide the velocity changes to hook up with the mobile mining colony, and then put you down on Mars.

Such a system would be low cost to build and run, but you need enough traffic (like 10,000 passengers a year) to justify building it.

about a month ago
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Utilities Should Worry; Rooftop Solar Could Soon Cut Their Profit

DanielRavenNest Re:Really? (517 comments)

The largest solar-thermal plant yet built, Ivanpah, at 400 MW capacity, is on the same transmission lines as Hoover Dam. Both are near Las Vegas. It doesn't need thermal storage because the dam effectively does the job. When Ivanpah is running, Hoover can save the water for other times of day.

When you look at a grid as a whole, instead of individual plants, you find synergies like this you can apply. Detractors of renewable energy tend to ignore that most plants are grid-connected, and power demands vary by time of day and season. Thus Ivanpah is well matched to Las Vegas. Peak demand happens when it is sunny and everyone is running air conditioning. Sunny is exactly when that plant is pumping out electricity.

Solar, however, is a poor match for the Pacific Northwest, because it is cloudy much of the time. Instead, hydroelectric and nuclear are the main sources up there. Lots of rain and mountains make hydro easier to build. Detractors will point to Germany and say solar sucks. Well, Germany is far north, and not very sunny. Italy and Spain are better suited climatically. Just because it doesn't work that well in one country or region does not mean it cannot work in better locations. The opposite example is Chile, which is rapidly installing solar. The high Andean plateau is not only exceedingly dry, it is cold and high altitude, both of which improve performance of solar panels.

about a month ago
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Forest Service Wants To Require Permits For Photography

DanielRavenNest Re: Forest Circus. (299 comments)

It is a permit for doing news reporting, including photography/viedography, within wilderness areas.

Then it violates the First Amendment "freedom of the press" clause. Charging the news media for exercising a constitutional right isn't allowed.

about a month ago
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PayPal Integrates Bitcoin Processors BitPay, Coinbase and GoCoin

DanielRavenNest Re: Recycling coins (56 comments)

Coinbase has 1.7 million user wallets ( https://coinbase.com/about ). I buy my bitcoins from them because I can pay via ACH transfer from my bank account. It's very convenient. My understanding is BitPay recycles their coins through exchanges.

> Why not just pay with regular money?

Most merchants who take bitcoin are online (76,000 total merchants, 5000 physical locations). Even in the US not everyone has access to a bank card, and outside developed countries the majority don't. Bitcoin doesn't arbitrarily seize or close your account because they don't like your business. If you need to send money right away (bank wires) or internationally at any speed, the fees are really high. Some merchants offer a discount for bitcoin purchases, because they get to avoid bank fees for debit/credit purchases, chargebacks, and fraud. Even cash has significant overhead - you have to monitor employees and customers, count it, take it to the bank, etc.

If all you do is buy stuff with your debit card at local stores, there isn't much reason to use bitcoin, but not everyone is in the same situation.

about a month ago
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Elon Musk Hints 1st Person To Mars May Go Via New Brownsville Spaceport

DanielRavenNest Re:Is this anything other than a press release? (91 comments)

> as there is nothing there

There is as much land area as the Earth. It just needs proper development. Las Vegas is in a fucking desert, and people live there anyway. The real problem is people who look at an empty piece of land and see nothing, rather than seeing the potential for what it could become.

about a month ago
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Nvidia Sinks Moon Landing Hoax Using Virtual Light

DanielRavenNest Re:I thought this was long ago debunked (275 comments)

There are many rational lines of evidence that the Lunar missions happened. My own personal ones include that I went to work at Boeing's space systems division in 1981, and the people who worked on the Saturn V and Lunar Rover *were still there*, as well as the project data. I've also visited the NASA repository where the two million microfiche cards with all the drawings are stored.

The problem is the conspiracy nuts are not rational. No amount of evidence will convince them, any more than you can convince a young Earth creationist that their holy book is bunk. Fortunately, science and technology doesn't depend on their belief. If a few well reasoned arguments don't convince someone, their mind is too closed to bother with. Just get on with your life. The conspiracy nut will still be able to get their satellite TV based on the same fucking technology that got us to the Moon :-) (big rockets).

about a month ago
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Original 11' Star Trek Enterprise Model Being Restored Again

DanielRavenNest Re:WTF (99 comments)

No. Fuck this. It's not a milestone of flight, and it doesn't belong there in the least.

I disagree. The original Star Trek, which I watched as a child, was one of the inspirations for me getting into aerospace and later working on the actual Space Station. The milestone isn't a particular flight it performed, but how many people it inspired, who later achieved great things in aerospace. In a prior generation, Wernher von Braun read Astounding magazine *while working on the V2 rockets*. There has always been a strong connection between science fiction stories and bringing those stories to life later.

about a month and a half ago
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Solar Powered Technology Enhances Oil Recovery

DanielRavenNest Re:Renewable (82 comments)

> As of 2014, how do you power trucks, tractors, cargo ships, and planes on solar?

Using bioengineered microbes to efficiently produce ethanol or diesel directly: http://www.jouleunlimited.com/...

The microbes don't have to produce leaf or stem structures, and are genetically engineered to emit the fuel molecules directly, like yeast emits alcohol. Except yeast poison themselves when the alcohol content in fermentation gets too high. The Joule Unlimited process draws off the fuel continuously, so the microbes can keep working. The efficiency limit is around 6% by this process, where standard photosynthesis is about 1%. Since the microbes are a contained system, you can use crappy dry land, rather than food-growing cropland, like we do for vehicle ethanol today.

about a month and a half ago
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3D-Printed Car Takes Its First Test Drive

DanielRavenNest Re:Yes! (132 comments)

Of course, the printer costs much more than a car, and is the size of a garage.

about a month and a half ago
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Congress Can't Make Asteroid Mining Legal (But It's Trying, Anyway)

DanielRavenNest Re:Barriers will fall once the money comes rolling (213 comments)

It's not Planetary Resources itself that has the influence, it is their list of advisers and investors. They include:

James Cameron (movie maker), Eric Schmidt & Larry Page (Google), Charles Simonyi (Microsoft Office, billionaire), Ross Perot Jr. (billionaire), and Richard Branson (Virgin Group).

about a month and a half ago
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Congress Can't Make Asteroid Mining Legal (But It's Trying, Anyway)

DanielRavenNest Re:Possession is nine-tenths of the law... (213 comments)

Elon Musk is working on the cheap access to space part of the problem, and I'm working on the other part.

That other part is a "Seed Factory", an industrial starter kit that makes parts for more machines in an expanding collection, using local raw materials and energy. So instead of having to send a whole asteroid processing plant, which would be pretty massive, you send a much smaller starter kit. We're about to buy a property near Atlanta to build and test prototypes for this concept. The first generation factories will be for Earth use, by the 3rd or 4th generation we should be ready for space use. In between we plan to do difficult and remote locations on Earth, like the oceans, deserts, and ice caps. That should give us experience in remote control.

about a month and a half ago

Submissions

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3D Chips with Internal Heat Pipes In Development

DanielRavenNest DanielRavenNest writes  |  more than 4 years ago

DanielRavenNest (107550) writes "Swiss researchers at EPFL and ETH Zurich are developing computer processors with stacked cores and internal 50 micron cooling channels that function like heat pipes, vaporizing the coolant and absorbing heat in the process. Thus it is literally vaporware :-) The article states "It will take a few years until 3D microchips equip consumer electronics. The initial 3D microprocessors should be fitted on supercomputers by 2015, while the version with an integrated cooling system should go to market around 2020." So it is vaporware in the other sense too, being 5-10 years out."
Link to Original Source
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Endless Copyright Free Music?

DanielRavenNest DanielRavenNest writes  |  more than 4 years ago

DanielRavenNest writes "UGR researchers Miguel Delgado, Waldo Fajardo and Miguel Molina decided to design a software programme that would enable a person who knew nothing about composition to create music. The system they devised, using AI, is called Inmamusys, an acronym for Intelligent Multiagent Music System, and is able to compose and play music in real time. The program is designed to create background music, of the kind you find in offices, not the next Billboard chart topper."
Link to Original Source
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Cyberporn to be easier to find on Second Life

DanielRavenNest DanielRavenNest writes  |  more than 5 years ago

DanielRavenNest (107550) writes "Second Life has plans to separate adult content both geographically and in its internal search engine starting with the 1.23 client software. There will be a new mainland continent on their grid, presently unnamed but jokingly referred to as Pornadelphia, which will be strictly adult map regions. Their search will also include ratings flags and filters to allow search by ratings level (PG, Mature, or Adult). More Detailed summary is here."
Link to Original Source

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