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I have met a number of people over the years who have had similar transformations. They went from doing what they believed the should be doing, to something they believed in/wanted to be doing. The transformation is huge.

Life is way to short.

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Nice work! I hope it is successful. There are a lot of useful things you can make with that demo board. Not to mention the Diglent PMOD boards which are fun to play with.

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One of my ops folks characterized Wordpress as a rootkit with a blogging package ride along. So hard not to see the ultimate truth in that

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That observation is probably related to http://www.bash.org/?949214 :)

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You can always ask what is the salary range for the position. If they refuse to tell you, you can stop the process early :-) but usually they will. Then if you fit in their range continue, otherwise walk away.

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I was thinking this as well. Car use seems to grow with industrialization and spread, then apparently shrinks with automation and urbanization. And if you look at the population that is entering into more general industrialization you see growing market for cars.

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Yeah, it was too bad they could not course correct it, but the telemetry is also cool. I agree with the author that it really boggles the mind that we have the ability to use our laptops, tethered to a phone, to send commands to an ancient satellite, to turn on its sensors. If that isn't the hook of an alien invasion thriller I don't know what is :-)

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At DEFCON no less. Not only do it, but do it in a hostile environment. Pretty amazing.

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I might be wrong but aren't you missing the giant radio telescope they used to send the commands?

Still awesome. I love how NASA helped with advisors and gave their okay.

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After Apple, SanDisk’s biggest customer is Samsung, according to data compiled by Bloomberg.

Really this is just a 'short SanDisk' article :-) But more seriously, it is interesting when supply chains get squeezed down to a single supplier, it is an unstable configuration historically as the supplier inevitably feels they aren't getting enough of the value[1] which then disrupts overall supply.

I am also really surprised that Intel hasn't more aggressively stepped in here, seems like there is some margin for the bottom line they can pick up.

[1] In all economics you're at a good balance if the seller thinks you paid to little and you think you paid too much.

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The only way Intel will get Apples business is to make ARM chips for it.

If you read the iPad chapter in Steve Jobs by Walter Isaacson, you would see that Intel was Jobs original pick for the iPad CPU. They fell out over a few issues, power consumption and control of the chip design being but two of them.

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Interesting, he wasn't wrong. And while Youtube is something of a 'fixture' today we had Google telling us it still wasn't making any money (although it had reached a point where it wasn't losing money either).

Youtube was birthed by business worlds version of Ceasarian Section, basically Google funded the crap out of it invested in datacenters and putting Youtube "pods" in bunches of Colocation facilities around the world etc for a property that doesn't make any money. But what is next for the video service? What business model works where it makes back its money? Does it try to be NetFlix? HBO Go? Comcast?

Does Google start throwing money at "Youtube Studios" to bring original (and with decent production values) content to the web? That is way outside their current comfort zone.

How do they get people to watch and act on advertising they see on Youtube? Because unless they can do that it has to be subcription, and how do you turn the service that everyone knows is "free" into a subscription service?

That is why I don't think it was wrong in 2006 or in 2015 to wonder if YouTube is a "real" business, I don't think we know yet.

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>Google funded the crap out of it invested in datacenters and putting Youtube "pods" in bunches of Colocation facilities around the world etc for a property that doesn't make any money.

When Google says YouTube doesn't make any money, they mean net of funding the crap out of it.

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Nice, that came in lower than I was expecting. I was thinking $5K for the 7kWh unit. Of course that is the "installers" price so who knows what those folks will consider the 'retail' price. My wife still has her solar installer certification so we could presumably get one that way.

It also makes for a really interesting opportunity for grid tied solar inverters. Now you want the inverter to power the house first, then push power to the batteries and only if they are full push it back to the grid. Software update for sure :-) of course it might make more sense to leave it DC for the push into the battery and only have the AC conversion happen post battery, so charge controller between the battery and the DC disconnect.

On a safety note I'd also really like to mount this outside, preferably against firebrick rather than my house. I realize the batteries are much safer than they have ever been, but still a cascading lithium battery failure inside my garage is not my idea of a party

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On the grid tied solar inverter front - the spec sheet says the battery voltage is 350~450 V, so we're looking at 108 lithium ion cells (25 x 18650 cells?) at 400 VDC nominal. This is quite different from typical lead acid battery pack voltage of 12, 24, or 48VDC that's used for battery backup storage, so a lot of existing solar battery storage infrastructure may not even work... this means that people may need to buy a whole new set of supporting hardware to integrate this into the existing solar systems instead of being able to update the software on existing hardware.

Lithium Ion also has quite a different (and much less forgiving!) charging cycle that requires much more monitoring of things like temperature, though I'd imagine a lot of that would be built-in as a safety mechanism directly into the Powerwall.

What I've heard is that National Electrical Code becomes much more stringent on battery systems greater than 48V, with the line drawn at 48V due to it being used widely in the phone landline system. I'm not sure how true that story is, but I'd imagine extra care is probably warranted. 10kWh is about 9kg of TNT. :-)

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Yes talk to telco Engineers from the power side of the biz and they will have war stories about accidents and close misses with the Central Offices (Exchanges) DC power.

High Voltage/Amperage DC is quiet different to AC power and i suspect that building/wiring codes are going to need to be updated if this local storage takes off.

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dropped a wrench across the terminals on the deep cycle backup batteries inside a telco switching center. Had to disconnect the whole bank of batteries to fix it because the wrench welded itself to the terminals. it wasn't a tack weld either.

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The one I remember is decorators placing a paint tin across the bus bars - which explosively painted the walls

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That makes for a very exciting day.

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Solar systems are generally HVDC off the panel. I think in practice you'd tie the three sources (grid, panels, battery) together in the AC domain with a computer monitoring consumption and generation then signalling the battery system to charge or discharge.

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Yes, it would be interesting to know if there's an advantage of connecting so many cells in series

Most systems limit themselves to something like 48v as you said (I think 48v is the threshold of "being dangerous")

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Higher voltage means lower current and thus lower voltage loss, and lower percentage losses for the same voltage loss, so you don’t need lots of copper.

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Yes, but you're throwing it into an inverter, and it's not like you're carrying it too far. High voltages also present problems in itself (isolation, etc)

Now, on a second thought, maybe it's more efficient to do 400VDC to 120VAC/240VAC (don't know the exact values)

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DC-DC buck converters may be a little simpler and more efficient than boost converters, I don't really know.

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48V is under the threshold at which electrical shocks become dangerous. 48V or less is "low voltage" class. And, 48V is a multiple of both 12V and 1.5V (most individual battery cells are 1.5V), making it much easier to hook up by using a combo of parallel and series connections.

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How about stuck to the side of your house?

From further down the comments, this is a rebranding of a battery already offered to SolarCity customers.

http://www.solarcity.com/residential/backup-power-supply

The image on SolarCity has been updated to show Tesla branding.

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Apropos of nothing but that product page has a lovely clean design.

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That was my thought took until I remembered people already steal copper wiring whether or not it's carrying load. That would be a tempting target for theft. I think I'd stick it in my garage instead, but that's just me being paranoid.

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Good point, hopefully the controller is DRM'ed to keep it from being used by a thief.

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Outdoors you're going to need to heat and cool it more - you want those cells kept within a fairly narrow range to keep the lifespan up.

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But you might not want someone to vandalize or steal the battery either which can happen if it's outdoors. Maybe it would be best to put it in a separate shed with lock or something.

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Ok, that 307,000' landing looked a bit painful (pretty big whumph at the end there) of course it hits the ground at 16mph if I did the conversion from 24 fps correctly.

But the really really odd thing for me is listening to the callout in feet and feet per second rather than meters and meters per second. I've gotten quite used to velocity in particular being called out in m/s.

I wish they were a bit more open with the progress they were making.

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Their website says that they employ solid landing rockets just before touchdown, similar to the Soyuz. The 'big whumph' is probably just dust kicked up by these rockets.

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On openness, give them time. I think Blue Origin's focus is on delivering a quality result in minimum time. Right now their customer is Bezos, and nobody else. I suspect you'll hear a lot more as they move toward flying paying customers.

http://blueorigin.com/astronaut-experience

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...feet and feet per second rather than meters and meters per second. I've gotten quite used to velocity in particular being called out in m/s.

Perhaps this is related to javert's flag comment?

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