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Comment: Re:Don't be silly. (Score 1) 104

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) 104

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) 104

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) 104

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: Re:FUD filled.... (Score 1) 212

It sounds like this transformer had its center tap grounded and was the path to ground on one side of a ground loop as the geomagnetic field moved under pressure from a CME, inducing a common-mode current in the long-distance power line. A gas pipeline in an area of poor ground conductivity in Russia was also destroyed, it is said, resulting in 500 deaths.

One can protect against this phenomenon by use of common-mode breakers and perhaps even overheat breakers. The system will not stay up but nor will it be destroyed. This is a high-current rather than high-voltage phenomenon and thus the various methods used to dissipate lightning currents might not be effective.

+ - Letter to Congress: Ending U.S. Dependency on Russia for Access to Space 1

Submitted by Bruce Perens
Bruce Perens (3872) writes "I've sent a letter to my district's senators and member of congress this evening, regarding how we should achieve a swifter end to U.S. dependency on the Russians for access to space. Please read my letter, below. If you like it, please join me and send something similar to your own representatives. Find them here and here. — Bruce

Dear Congressperson Lee,

The U.S. is dependent on the Russians for present and future access to space. Only Soyuz can bring astronauts to and from the Space Station. The space vehicles being built by United Launch Alliance are designed around a Russian engine. NASA's own design for a crewed rocket is in its infancy and will not be useful for a decade, if it ever flies.

Mr. Putin has become much too bold because of other nations dependence. The recent loss of Malaysia Air MH17 and all aboard is one consequence.

Ending our dependency on Russia for access to space, sooner than we previously planned, has become critical. SpaceX has announced the crewed version of their Dragon spaceship. They have had multiple successful flights and returns to Earth of the un-crewed Dragon and their Falcon 9 rocket, which are without unfortunate foreign dependencies. SpaceX is pursuing development using private funds. The U.S. should now support and accelerate that development.

SpaceX has, after only a decade of development, demonstrated many advances over existing and planned paths to space. Recently they have twice successfully brought the first stage of their Falcon 9 rocket back to the ocean surface at a speed that would allow safe landing on ground. They have demonstrated many times the safe takeoff, flight to significant altitude, ground landing and re-flight of two similar test rockets. In October they plan the touchdown of their rocket's first stage on a barge at sea, and its recovery and re-use after a full flight to space. Should their plan for a reusable first-stage, second, and crew vehicle be achieved, it could result in a reduction in the cost of access to space to perhaps 1/100 of the current "astronomical" price. This would open a new frontier to economical access in a way not witnessed by our nation since the transcontinental railroad. The U.S. should now support this effort and reap its tremendous economic rewards.

This plan is not without risk, and like all space research there will be failures, delays, and eventually lost life. However, the many successes of SpaceX argue for our increased support now, and the potential of tremendous benefit to our nation and the world.

Please write back to me.

Many Thanks

Bruce Perens"

Comment: Re:a question.... (Score 1) 64

by Rei (#47516505) Attached to: Oso Disaster Had Its Roots In Earlier Landslides

That's not what everything I've read about the disaster has said. The mountain has gone through cycles - whenever it collapses, the river gets moved away, and the slides stop for a time, but eventually it wears away the footings enough that it falls again. They'd even tried to prevent landslides there by manually shoring up the base back in the 1960s, but it just flowed over their reinforcements.

The waterlogging of the soil is also a necessary factor too, mind you - not saying otherwise. :)

Comment: Re:a question.... (Score 1) 64

by Rei (#47516433) Attached to: Oso Disaster Had Its Roots In Earlier Landslides

I had paperbark birch seeds, which are also pretty water tolerant (though not as much as river birch), but none sprouted - ironically I think the seeds were too wet when I stratified them (same with my maples). Isn't river birch (B. nigra) a warm-weather birch species? I've got some cuttings of random local birches from a neighbor but I have no clue whether any of them are water tolerant enough to take swampy ground. Also birches don't usually get that tall so I don't know how expansive of a root system they'll put down. The abundant local species B. nana (dwarf birch) grows (nay, volunteers) readily here almost anywhere that sheep don't graze, but it's just a shrub, I doubt it'd do the trick (though it's probably better than just grass). It can take wet soil, although not totally swampy conditions.

For the wetter areas I also have about a dozen or so western redcedar seedlings - they're not as swamp-tolerant as dawn redwood and western recedar, but they're still reportedly quite tolerant of wet or even waterlogged soils, and they should be more cold/wind hardy than those two (wind is actually the big issue, it doesn't really get that cold here). I've also got a number of other pacific northwest trees with varying degrees of standing water tolerance. Oh, and a species or two of tasmanian mountain eucalyptus (don't remember which ones) that tolerate fairly swampy ground and should at least stand a fighting chance against our winds.

Basically, I'm just going to plant a ton of stuff and see what survives. ;)

One plus is that where the ground is persistently wet and at landslide risk, it is slowly flowing water, it's not standing. It's constantly replaced by fresh, cold ground-filtered water, so there's probably not as much risk of root rot as might be common otherwise. But there's still the oxygen issue. That and the damned sheep, but I'm working to fix that issue once and for all...

Comment: Re:a question.... (Score 1) 64

by Rei (#47514829) Attached to: Oso Disaster Had Its Roots In Earlier Landslides

To be fair, if you look at the scale of that thing, what fell is far deeper than tree roots are going to go.

There was a landslide on my land a few years ago... actually just 50-100 meters from where I'm getting ready to build my house (but the terrain is different, that's a groundwater-infiltrated glacial till-underlain marsh while my house site is basalt bedrock). It's weird looking at pictures of this giant slide, how much it looks like a 20x bigger version of my little one, from the smooth, rimmed conchoidal scarp to the river-damming piles of debris at the bottom. In my case, there were no trees, but there was grass. The grass managed to hold it for a while... but not forever. The roots just don't run deep enough. In my case, the solution (in progress) is surely just to plant water-tolerant trees (here's to hoping that dawn redwood and swamp cypress can survive in Iceland...). But what sort of trees could anchor such a massive slope as the Oso one? I know a lot of desert trees like mesquite can have super-deep root systems, but they wouldn't grow in Washington.

Sigmund Freud is alleged to have said that in the last analysis the entire field of psychology may reduce to biological electrochemistry.

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