Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror
×

Comment Re:Really? (Score 3, Interesting) 517

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.

Comment Re: Recycling coins (Score 1) 56

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.

Comment Re:Is this anything other than a press release? (Score 2) 91

> 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.

Comment Re:I thought this was long ago debunked (Score 1) 275

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).

Comment Re:WTF (Score 3, Interesting) 99

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.

Comment Re:Renewable (Score 1) 82

> 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.

Comment Re:Barriers will fall once the money comes rolling (Score 1) 213

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).

Comment Re:Possession is nine-tenths of the law... (Score 1) 213

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.

Comment Re:LOL (Score 1) 213

*Let me try and clarify: I can plant a quartz mine on the Moon, but I can't stick a forty foot perimeter fence around it and I can't prevent my competitor building a quartz mine five feet away.

Actually, spacefaring nations have already laid out operational safety rules. For example, the ISS has a 1 km "keep out zone" around it. For the Moon, you can't place your landing pad so close to my mine that it kicks up rocks and damages my equipment, and conversely outgassing from my mine processing can't contaminate your solar arrays. Once people actually set up operations on the Moon or some asteroid, there will be reasonable *and agreed to* safety boundaries and access roads, which will, over time, become property lines and public roads. For the latter to happen, you will need to reach a point where people are buying, selling, and subdividing land, and sharing costs for transport improvements.

Assuming the 1 km keep-out zone is adopted for asteroid mining, then any asteroid smaller than 1 km will be the province of one mining operation, unless they set up as a multinational or joint corporate project (which is actually pretty likely).

Comment Re:Can someone clarify the state of BitCoin? (Score 1) 134

That deflation is dangerous is a myth perpetrated by the banking cartel. People have short term needs, like food, housing, and utilities. They will continue to buy those things regardless of whether inflation is +2% or -2% (i.e. deflation). Investors with a clue adjust nominal returns to "real" returns after inflation. Deflation just means they make that adjustment the other way. They still demand a certain real return for a given risk level, so the nominal return will adjust to get it.

Bitcoin represents around 0.025% of world currencies on an M1 basis, and an even smaller fraction of all tradable assets. Nobody bases their economy on it, so the deflation argument is moot. It's just another commodity with a variable value, but one well suited to be electronically traded.

If bitcoin ever became a significant fraction of world trade, you can be sure that competing financial interests would set up their own versions, and then the total units in circulation would not be limited any more. There are already at least 478 such "altcoins" (http://coinmarketcap.com/), but most have trivial value because they were set up by one or two people as a hobby. A serious one would be set up by existing financial exchanges or a government, and backed by a pool of assets to give it stability.

Comment Re:1 week's warning (Score 1) 68

The implied point is that perhaps we should be putting some effort into getting more warning and finding all the dino killers (and frankly, stuff a lot small than that rock was).

That is in fact what NASA has been doing for the past two decades: http://neo.jpl.nasa.gov/stats/ They have found about 90% of the 1-km or larger class. Chixulub the dino killer is estimated at 6 km, and impact energy scales as the cube of diameter. Unfortunately, asteroid tracking doesn't help with long-period comets. Those come in from the dark reaches of the outer Solar System, and therefore cannot be found until they are within a couple of years of hitting us.

Comment Anthropometrics (Score 4, Interesting) 819

Since they have apparently reached the limit of human tolerance, one answer is to offer wider seat spacing for a little extra price on some flights. The remaining "dense pack" passengers then have no reason to complain: "If you needed more space, why didn't you choose our XL flight?"

Slashdot Top Deals

The moon is made of green cheese. -- John Heywood

Working...