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Comment: Re:Headline trifecta (Score 4, Interesting) 67

by halltk1983 (#47576083) Attached to: Nevada Construction Project Could Be Tesla/Panasonic Gigafactory
You can't use car batteries in your home. They make toxic fumes. You'd have to use marine-quality sealed batteries. And at the scale for your home, you're talking real money, usually around $5000-7500 in just batteries. They're heavy, bulky and take up a lot of room. Just think of putting 20-30 car batteries in your home. Plus you'll need to replace all of them every 3 years or so. If they can make a battery pack for $10,000 that's a fifth the size, lasts 10-15 years, and comes warrantied for use in specifically that method... that's a really big win.

Comment: Re:Don't be silly. (Score 1) 117

by Rei (#47550685) Attached to: Stanford Team Creates Stable Lithium Anode Using Honeycomb Film

I actually totally get Amazon's logic on this one. If there's only a $10 extra profit on each drone delivery (something I'm sure tons of people in range of the service would pay for in order to get their item in half an hour), and if we assume each drone operational cycle takes one hour (delivery, return, charging), then that's $240 a day. Doesn't take a lot of days to justify the cost of a drone with a return like that.

Comment: Re:Every month a new battery breakthrough, but.. (Score 5, Insightful) 117

by Rei (#47550589) Attached to: Stanford Team Creates Stable Lithium Anode Using Honeycomb Film

Except that you have bought them; you just haven't realized it. Energy density of li-ion batteries has grown by about 50% in the past five years. Have you seriously not noticed how cell phone and laptop battery mah ratings keep growing while they keep making the volume available for the batteries smaller?

It's big news when a new tech happens in the lab. It's not big news when the cells first roll off a production line.

Most new lab techs don't make it to commercialization. But a lucky fraction of them do, and that's the reason that you're not walking around today with a cell phone with a battery the size of a small brick.

Comment: Re:More Range Needed (Score 2) 117

by Rei (#47550555) Attached to: Stanford Team Creates Stable Lithium Anode Using Honeycomb Film

If everyone last person was going to be driving electric cars tomorrow, yes, that would be a problem.

Given that that's not the case, and for decades it's always going to be such that the people whose situation best suits an electric car are going to be the next ones in line to adopt them, then no, it's not a problem. You really think people can't build curbside/parking lot charging stations over the course of *decades* if there seems to be steadily growing interest in EVs?

As a side note, I don't know those exact neighborhoods in your pictures, but in my experience, most people who live in such places don't own *any* car.

Comment: Re:More Range Needed (Score 1) 117

by Rei (#47550501) Attached to: Stanford Team Creates Stable Lithium Anode Using Honeycomb Film

Actually, 800 is quite a sensible number. At an average speed of 60 miles per hour (aka, factoring in driving / bathroom / meal breaks), that's 13 1/2 hours of driving - a good day's drive. Throw in a few more hours driving time / a couple hundred miles more range if you charge while you're taking your breaks. Once you get that sort of range, charge speed becomes virtually irrelevant because it happens while you're sleeping (and getting ready for bed / getting up in the morning). A regular Tesla home charger could handle that sort of load.

I agree with you that a half hour charge isn't actually that onerous, but it definitely will scare off people who are used to filling up faster. And charge stations that can do half hour charges on 300 miles range (150kW+ for an efficient car, more like 250kW for a light truck) are exceedingly rare as it stands. A charger that powerful isn't some aren't some little wall box with a cord hanging off of it, it's the size of a couple soda machines put together (bigger if you add a battery buffer so that you don't need a huge power feed) that feeds so much power that its cable has to be liquid cooled and which costs around $100k installed. Ten minute charges are, of course, around three times that size. I've only ever come across mention of *one* charger in the ballpark of the required 750kW to charge a 300 mile light truck in 10 minutes - an 800kW device custom made a couple years back for the US Army Tank Command. I have no clue what it cost, but I'm guessing "Very Expensive".

I'm not saying that the problem is intractable, by any stretch, I totally believe that we're going to transition over to EVs. I just question the sort of time scales that a lot of people envision. The average car on US roads is 10 years old. Implying an average 20 year lifespan. And many cars don't get scrapped then, they just go to the third world. Even if you suddenly switch all new car manufacturing over to EVs, you're talking decades to replace them. But of course you can't just switch over like that - even if everyone was right now sold on the concept of EVs with current tech, you're talking at least a decade, possibly more, to tool up to that level of production. But of course, not everyone is right now sold on the concept of EVs with current tech.

Realistically, you're looking at maybe a 40 year transition. I hate to say that, because I love EVs, but I'm not going to just pretend that the reality is other than it is.

I'll also add that while fast chargers are big and expensive, the size and cost actually are comparable to building a gas station on a per-pump basis, and the economic argument works out for making them even if there's only a reasonable (50% or less) surcharge on the electricity sold and if they're only selling electricity a couple percent of the time. But you need to get a couple percent of the time usage to economically justify them - one person stopping for 10 minutes every few days just isn't going to cut it. And not every EV is going to stop at every charger even if they're driving on the same route - if your chargers are that far apart, then that means you're pushing people's range so much that they're not going to be comfortable driving that route. All together, this means that if you want to have fast charging infrastructure economically justifiable in an area you need high EV penetration, where several dozen EVs driving long distances will be going by each charger every day - even out in the boonies. And when you're talking at prices on the order of $100k per unit, you're no longer talking about a range where peoples' goodwill toward EVs or interest in having a loss leader outside is going to pay for them.

Basically, while busy interstate routes on the coasts and the like can economically justify them with a small fraction of a percent of people driving EVs, out in the boonies, they're going to be stuck with smaller, cheaper, slower chargers for a good while. Unless people are willing to pay a big surcharge on the electricity sold, that is (500% surcharge instead of 50% = 1/10th as many vehicles needed).

Comment: Seriously, fuck Greenpeace. (Score 1) 288

by jcr (#47541405) Attached to: Greenpeace: Amazon Fire Burns More Coal and Gas Than It Should

They're like the goddamned Westboro Baptist Church, trying to leech publicity from anything that makes the news. They are not, and have never been an environmentalist organization. They're a marketing organization, that sucks up money by guilt peddling.

If you want to help the environment, then donate to a local group in your area, the Sierra Club, Ducks Unlimited, or any of dozens of others.

-jcr

Comment: More on MA (Score 1) 157

by fyngyrz (#47539203) Attached to: Soccer Superstar Plays With Very Low Brain Activity

That translated into martial arts is roughly the equivalent of a 4th DAN, but for that you need longer due to 'regulations regarding examinations', waiting periods between 2 examinations.

Depends on the martial art. The most modern practice recognizes natural talent while incorporating considerable traditional technique; I assure you, everyone does not walk into their first day of training on an equal basis -- I've been teaching for decades and I think I've seen about every level of beginner skill there is. Some people are simply gifted. Certainly from there on in we see the difference between the shows-up-once-a-week and the person who seems to be there every hour they can possibly manage.

Also, more on topic, I can definitely assure anyone who is curious that you're not doing high level thinking when executing advanced martial arts techniques.

All you really need to do to understand this is think about bike riding. When you learn, you learn, you think like crazy. Which does you very little good. But eventually, you internalize the process (that's what I call it, anyway) and you can do it while carrying on a conversation with someone else, paying almost no attention at all to the activity of riding the bike. Those near-instant balance corrections, the precise amount of handlebar control and lean for cornering, all of that comes from "underneath." Same thing for advanced MA.

That whole business about finding your calm center and holding it -- that's a real thing. If you start thinking under threat or pressure, your performance will drop like a stone. The best technique comes from a relaxed, centered condition, accepting of whatever comes.

He keeps differentiating, flying off on a tangent.

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