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Comment Re:So, basically, it matches a current gaming PC (Score 1) 135

PC gamers are notorious for overestimating power supply requirements. The wattage craze is completely unwarranted UNLESS you overclock. At stock clocks, the cards are actually pretty power efficient. See this graph for example. Under max load, a GTX 1070 draws maybe 150W by itself. Combine that with a 65W TDP CPU (e.g. Core i5 7600) and you're only at 215W at max load. Add in 5W for memory and 15W for the HDD and you can still fit yourself into 235W, 10W less than 245W. Now consider that the XBox Scorpio's CPU & GPU will be lower clocked than your average PC rig and you can see how they can fit into 245W. Also see this short informative video on the same subject.

Comment Re:Electric jet? (Score 1) 163

Which is why I wrote it, dummy! -_-

What confused me is your obvious lack of understanding of jet propulsion. See below.

The question posed was, "[h]ow can a jet be electric?", not what's efficient and realistic model for air transport. Stop assuming!

Your response makes little sense to answer the question, hence the confusion. It's like you think "jet propulsion" must require combustion. It doesn't. In fact, in modern jet engines, the vast majority of their thrust (not power) doesn't come from combusted exhaust gas. To make a electric jet engine, all you have to do is cut out the turbine engine core and replace with a powerful electric motor. What you are left with is a compressor fan feeding a propulsive nozzle. No need to go into weird atmospheric chemistry territory to create a pointless intermediary fuel. Just drive the fan electrically and be done with it.

Comment Re:Electric jet? (Score 1) 163

I wasn't sure what he was proposing, so that's why I asked. If he meant to create combustible fuels from the atmosphere by inputting energy and then just using said fuel for propulsion, then that's at least not apriori not thermodynamically impossible, assuming that the produced fuel isn't used to generate more energy than was put in. What makes it silly, however, is the inefficiency of this idea.

Comment Re:One potentially useful application - taxiing (Score 1) 163

The Concorde was extremely wasteful. Just ran the numbers on this using a modern plane. On a *very* short flight from London Gatwick to Amsterdam (route length just 240nm, about 40 minutes flight time) using an Airbus A319 burns around 2050 kg of fuel. Assuming a 20-minute taxi (15 minutes out, 5 minutes in, two-engine taxi both ways) consumes 200 kg. That's pretty close to the worst case and even so it's only about 10%. On the other hand, on aircraft of this size, the common rule of thumb of extra weight vs enroute fuel burn is that carrying an extra 1000 kg of weight equates to about an extra 100 kg of fuel burn per hour. So depending on the extra weight of the batteries, electric motors and gears, if it is a decent fraction of a ton, you'll have decreased your savings easily by maybe 50-100 kg (and the cost grows linearly with flight length, unlike relative taxi fuel cost, which decreases with flight length).

Comment Re:Electric jet? (Score 1) 163

A jet can be fully electric if it uses the atmosphere from the intake to create a combustible fuel and then combusts it. This would require a lot of energy but it is possible since our atmosphere can be broken down into combustible components.

Please explain this miracle of thermodynamics-defying chemistry in more detail. I would really like to have free energy.

Comment Re:What abuot the weight problem? (Score 1) 163

which is presumably what these guys did

They are also decidedly tight-lipped about this on their own website, which contains nothing but wishy-washy rhetoric, much in the vein of TFA and this summary. No hard data, no technical details, not even a clarification of what terms like "hybrid" mean. It might be completely legit, but so far this gives off the distinct smell of venture bullshit - seems to fall into the same category of feel-good investment blackholes projects like AirCarbon and Solar Roadways.

Comment Re:Speaking of computers... (Score 1) 340

Alright, so we have finally arrived at the insults. And "butthurt"? Seeing as you're the one wanting to throw insults, feels to me like you're projecting. Maybe you should have asked me "why do you think this is a bad idea?". Then you wouldn't have to assume I wanted you to take my word for it.

Comment Re:Speaking of computers... (Score 1) 340

Ah yes, the classic "but they mocked the Wright brothers!" excuse. To that, all I can summon is the power of Carl Sagan:

But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright Brothers. But they also laughed at Bozo the Clown.

This circular runway idea falls straight into the "clown" category.

Comment Re:Speaking of computers... (Score 1) 340

That part was my opinion, not some broad consensus. Of course you'll find people fapping about stupid ideas everywhere just because they sound "cool" at a first glance. Look at the mountain of shitty kickstarters that promised the world, raised huge sums and ultimately ended up going bust, because "cool" doesn't necessarily translate into "viable".

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