jnw2

11 ms·

61.
by jnw2 14y ago
Model S makes use of SAE J1772 only via an adapter, and it's not clear that the average Model S owner is going to make frequent use of J1772. Tesla is recommending that Model S owners either install an RV style 50A 240V outlet in their home
62.
by jnw2 14y ago
If you're driving 500 miles a day two days in a row to cover a total of 1000 miles, can the early adopters really expect to find a suitable 240 V, 30-50 A charging station at their hotel, or are they going to resort to stopping at a superch
63.
by jnw2 14y ago
There are some interesting questions about economies of scale, etc, though. If we figure an average American has a lead acid car battery and maybe a laptop battery pack, we currently have more lead acid batteries than lithium ion, certainly
64.
by jnw2 14y ago
IIRC, solar prices have been dropping at a rate of 7% per year. If that keeps up, and if the grid price remains constant, solar will eventually become cheaper than grid. In 1992, would you have told me today's smartphones would be impossib
65.
by jnw2 14y ago
Several strings of solar panels + lithium ion batteries might very well be cheaper than paying your local electric monopoly for transmission line capacity in 20 years. And if the non-redundant parts (the inverter, perhaps) fail, it might n
66.
by jnw2 14y ago
Mass transit has some advantages with predictable trip lengths: no transit agency is going to insist that they need a bus that can go 200 miles on a charge if their average bus only travels 50 miles each morning. Meanwhile, the average con
67.
by jnw2 14y ago
I bet batteries don't tend to like going from full to empty in the time it takes to launch a plane. I wouldn't be surprised if later in the Ford class's life, we do see supercapacitors taking over.
68.
by jnw2 14y ago
http://en.wikipedia.org/wiki/A1B_reactor indicates that there's 300 MW per reactor on the Ford class, and two reactors, so maybe 600 MW total, although I'm not sure if that's the output of the steam powered electrical generators, or if it
69.
by jnw2 14y ago
http://en.wikipedia.org/wiki/USS_Gerald_R._Ford_(CVN-78) notes that ``Unfortunately the power limitations for the Nimitz class make the installation of the recently developed [Electromagnetic Aircraft Launch System] impossible.'', which s
70.
by jnw2 14y ago
I'm not in the bay area. Given your constraints, I wonder if what you actually want is one switch for each upstream, and a gigabit link from each of your physical Xen servers to each switch that goes to an upstream. If your switches have t
71.
by jnw2 14y ago
Elon has five children. Getting Elon + 5 children into a Tesla is a key goal, and presumably his smallest child is going to outgrow the optional rear facing seats in the Model S at some point...
72.
by jnw2 14y ago
A Xeon E3-1220 has an 8MB L3 cache and costs about $210. If you deaggregate the entire IPv4 routing table to /24s to support fast lookups and store one nibble of destination data per route (probably just a destination interface number, if
73.
by jnw2 14y ago
How well would the average US city cope with providing enough tap water for its population suddenly tripling?
74.
by jnw2 14y ago
Improving medical technology with a goal of curing currently-uncurable diseases, making health care cheap enough to make Medicare sustainable (perhaps specifically by looking for ways to eliminate 90% of the costs associated with the half d
75.
by jnw2 14y ago
Did Carter show anywhere near as much leadership in pushing the limits of technology as Admiral Rickover did, though?
76.
by jnw2 14y ago
If we had one of the surplus Hubble-diameter Naval Reconnaissance Office mirrors orbiting Mars with a suitable camera, would we have better pictures than this? And could one of those mirrors be mounted in the trunk of a SpaceX Dragon spacec
77.
by jnw2 14y ago
I'm not sure the EV charging at night thing will continue forever; Germany has already had a Saturday where their solar panels covered 50% of their electricity needs for a few hours, so if they double or triple or quadruple their solar capa
78.
by jnw2 14y ago
On the other hand, Tesla is busy getting luxury car buyers to help subsidize the capital investment in building storage on a bigger scale, and nobody has figured out how to get luxury car buyers to subsidize grid improvements. In the long t
79.
by jnw2 14y ago
http://googleblog.blogspot.com/2009/07/should-you-spring-cle... indicates that solar panels mounted flat do indeed need to be cleaned, but panels mounted at a sufficient angle will be rinsed off adequately by the rain and do not seem to b
80.
by jnw2 15y ago
Would the founders of a startup who are willing to pivot as needed get something lower than the highest possible grit score?
81.
by jnw2 15y ago
I was under the impression that Amtrak from Newark Airport to 30th St Station in Philadelphia was available as an airline code share (and that train segment is fast enough that there's no good reason to get on a plane for Newark<->P
82.
by jnw2 15y ago
I've certainly seen virtualization environments where RAM is a much larger fraction of the physical server's cost than the CPUs. How much RAM are you using when you aren't using many CPU cycles?
83.
by jnw2 15y ago
The Americans with Disabilities Act may not have much sympathy for the inconvenience of providing accessibility, though.
84.
by jnw2 15y ago
Is there a good argument against Oracle releasing ZFS under the GPL (so that it could be integrated into the Linux kernel)?
85.
by jnw2 15y ago
IIRC, a post to NANOG a while ago claimed that the cost to run fiber to the home is well over $1k/household. I think the math works out to the conclusion that neither Netflix nor Google has enough money in the bank to run fiber to a large
86.
by jnw2 15y ago
Did the local electric utility decide it wasn't worth running 120V power to your home either? I don't know of any reason that running fiber is any more expensive than running power lines (if anything, being able to piggyback the fiber on e
87.
by jnw2 16y ago
There are also airplanes without radios (though such planes normally operate at untowered airports).
88.
by jnw2 16y ago
http://www.avweb.com/news/sayagain/191072-1.html has a (now retired) US air traffic controller's thoughts on a fatal collision involving two of the three planes a European controller was responsible for. It suggests that not all cases of
89.
by jnw2 16y ago
But maybe an electric car needs a gasoline engine as much as a tablet computer needs a keyboard, and maybe we're several years away from seeing that in the electric car case, just as the belief that a tablet didn't need a keyboard didn't be
90.
by jnw2 16y ago
Even lengthening existing Amtrak trains can take years of time and bureaucratic approval. The design of the Acela trainsets is such that Amtrak could add four more business class cars, which would double the number of business class seats

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