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Comment: Re:That's not quick? (Score 1) 155

by Rei (#47727763) Attached to: How Does Tesla Build a Supercharger Charging Site?

I'm assuming that's not a 30 minute Tesla fast charge station, since that's only 50kW.

The two issues I have the most interest in are 1) whether they use some sort of battery buffer to balance loads on the grid connects (otherwise I think the utility company won't be very happy with the unpredictable megawatt drains ;) But maybe the utility company is handling balancing on their side), and 2) how cooling on the charger is handled. Just simple resistance calcs show that once you get to really high power chargers, you have to cool the wire to the car to keep its heating to an acceptable level at an acceptable cable mass, so I'm curious how they handle that. Personally I've felt that high power rapid chargers should provide coolant for the car itself as well via the charge port. Why should the car have to haul around such a major cooling system and coolant reservoir when the charger already has to have it and has to cool its cable all the way up to the car? However, I've never heard of anyone actually implementing such an approach.

Comment: Re:And how long does it take... (Score 1) 155

by Rei (#47727723) Attached to: How Does Tesla Build a Supercharger Charging Site?

Not to mention that they can be a loss leader. 250Wh/mi at a commercial power rate of $0.08/kWh is two cents per mile. So a 150 mile charge is $3. There are lots of businesses that would pay $3 to keep a potential customer there for half an hour, esp. if said potential customer will likely feel appreciate and that "he owes them". Charging can also be "free with purchase", and businesses can limit the charge rate if $3 for a half hour chage is too steep of a loss leader for them.

All this ignoring the green cred / pr advantage of offering said charging in the first place.

Comment: Re:And how long does it take... (Score 1) 155

by Rei (#47727703) Attached to: How Does Tesla Build a Supercharger Charging Site?

(in fact, that's another big problem with EVs in urban areas without private parking, but it's besides the point subject here).

It's also irrelevant. Even if everyone was suddenly sold on the concept of EVs, it would take decades first to be able to ramp up production to match that of gasoline cars, and then to phase out all of the gasoline cars on the road. It should be obvious, yet someone seems to pass right over EV opponents, that the first adopters are going to be those for whom it best suits their situation, and that it will only slowly migrate - over decades - down to an increasingly broad section of the population.

If humans are incapable of recognizing and responding to a slow, patently-obvious, decades-long-process by merely building power outlets, then the species unworthy of the term sentient.

(And just an extra FYI: The majority of people, in my experience, who live in urban areas without private parking take public transportation and don't own any car... but maybe you're referring to some other situation I'm not familiar with).

Comment: Re:And how long does it take... (Score 3, Insightful) 155

by Rei (#47727671) Attached to: How Does Tesla Build a Supercharger Charging Site?

As for my other issues with your post.

1. Actually time yourself going down the highway when you're on a long trip, from the moment you begin to decelerate to begin to get gas, to the moment you're back on the road up to highway speeds, and don't leave out the things people often due during stops long trips (why long trips? more in a second), including bathroom breaks, buying something at the convenience store, cleaning the windshield, heading over to a nearby restaurant to grab a bite to eat, whatever. Time a number of different stops on a long trip and average them out. You'll find they're a lot more than 5 minutes. EVs have all of that extra stuff too, mind you, but a lot of them can be done while charging, and even for the other stuff, you're adding a constant overhead, which reduces the ratio of the non-constant aspect (the actual filling itself).

2. Why constrained to long trips? Simple - because people don't stop at charging stations when they're not on long trips. It's pointless. You charge at home, and maybe when parked at other places like work or a mall if there happens to be a plug near you. It's a great inconvenience of gasoline cars which EVs don't have that one must regularly waste time at gas stations in their daily lives regardless of how long trips are. Overall gasoline car drivers waste a lot more time "filling up" than EV drivers. (and if you disagree and think the mere act of plugging and unplugging gives the edge to gasoline drivers somehow, then that still doesn't help with the wireless EV charging that's getting a lot of focus now, where you merely have to park and you start getting charge)

3. The page you linked for dimethyl ether said nothing (that I noticed) about generation from just electricity and, say, air/water. It did say that in the lab it can be made from cellulosic biomass (although it should be noted that no cellulosic fuel techs have thusfar worked out at a commercial scale). Let's just say you can do that, and that you get the 1000 gallons per acre-year reported for switchgrass.That's 0,93 liters per square meter-year. It's reported at 19,3 MJ per liter, so we have 18MJ per square meter per year. Let's say we lose 5% of this to distribution, and then burn it in a car running at a typical 20% average efficiency (peak is significantly higher, but peak isn't what matters). We have 3,4 MJ per square meter per year.

Now what if we ran EVs on solar panels on the same land? Let's say the solar farm is 50% covered with solar panels and gets a capacity factor (clouds, night, etc) of 20% and a cell efficiency of 20%. 1000W/m, so 20W/m electricity is produced on average. That's 20 joules per square meter per second, so 631 MJ per square meter per year. We reduce it by the average US grid efficiency of 92% and an average wall-to-wheels EV efficiency of 80% and we get 465 MJ per square meter per year. 136 times as land-efficient as the biofuel alternative

Now let's say we leave out all of these lossy bioprocesses behind and generate some sort of biofuel straight from electricity at a very unrealistic 80% efficiency (most processes for realistic fuels are way lower), plus the same generous 5% distribution losses, and that it's afforable. And let's say that they all burn their fuel at an impressive 40% efficiency (even fuel cells, while higher in peak efficiency, generally can't do that tank-to-wheels in real-world vehicle usage). Thus we get 192 MJ per square meter per year, 41% that of the EV. Are you really comfortable with plastering 2.4 times as much of the earth's surface with solar panels? Or 2.4 times more wind turbines, 2.4 times more dammed rivers, 2.4 times more nuclear power plants and uranium mining, etc? Is that, in your view, an ideal solution, even in this comparison highly biased in favor of fuels versus electricity?

Electricity is the universal energy currency, and we shouldn't be wasting it converting it between different forms needlessly. Not only does it mean a dramatically worse impact on the planet, it also means that even if your electricity to fuel conversion process is practically free in terms of consumables and capital costs (the reality generally being anything-but), that you have to pay many times more per kilometer that you drive, as you're (indirectly) consuming many times more electricity.

Comment: Re:And how long does it take... (Score 3, Informative) 155

by Rei (#47727513) Attached to: How Does Tesla Build a Supercharger Charging Site?

Now of course gas stations don't always have fully occupied pumps and that's the point, so that almost whenever you arrive, there's a free pump available.

That actually doesn't help your argument any. The longer it takes to fill up, the more you smooth out the random demand fluctuations.

Let's say the time per pump is 5 minutes and the time per charger is 30 minutes, so we have to build 6x more chargers to service the same number of vehicles (and that you have to build the charging stations more frequently due to the range). So we'll compare a 4 pump gas station with a 24 charger EV station. So let's say that we get the following rate of people arriving (picking some numbers at random):

1:00: 1
1:05: 0
1:10: 6
1:15: 7
1:20: 3
1:25: 0
1:30: 0
1:35: 2
1:40: 1
1:45: 8
1:50: 6
1:55: 0
2:00: 1

What happens in these scenarios? First, gasoline:

1:00: 1 pump in use
1:05: 0 pumps in use
1:10: 4 pumps in use, 2 people waiting
1:15: 4 pumps in use, 5 people waiting
1:20: 4 pumps in use, 4 people waiting
1:25: 4 pumps in use, 0 people waiting
1:30: 0 pumps in use
1:35: 2 pumps in use
1:40: 1 pump in use
1:45: 4 pumps in use, 4 people waiting
1:50: 4 pumps in use, 6 people waiting
1:55: 4 pumps in use, 2 people waiting
2:00: 3 pumps in use, 0 people waiting.

What about the charging station?

1:00: 1 charger in use
1:05: 1 chargers in use
1:10: 7 chargers in use
1:15: 14 chargers in use
1:20: 17 chargers in use
1:25: 17 chargers in use
1:30: 16 chargers in use
1:35: 18 chargers in use
1:40: 13 chargers in use
1:45: 14 chargers in use
1:50: 17 chargers in use
1:55: 17 chargers in use
2:00: 18 chargers in use

With the gas station, 23 people needed to wait, some of them for a rather long time. With the charging station, nobody needed to wait. Despite the fact that the charging is 1/6th the speed, that doesn't actually imply you need 6x more chargers. In the above example, we see that the gas station should have had 8 pumps while the charging station 18 chargers, or 2.25x more.

More on the other problems with your post in just a second - I just felt that this particular aspect deserved a whole post on its own.

Comment: Re:That's not quick? (Score 5, Insightful) 155

by Rei (#47727425) Attached to: How Does Tesla Build a Supercharger Charging Site?

Not to mention that building a gas station takes a heck of a lot longer.

It's one thing I don't get about EV opponents. Not only are EVs supposed to not have any new inconveniences relative to gasoline vehicles, and not only do inconveniences that gasoline vehicles have that EVs don't have not count toward EVs, but EVs aren't even allow to have the inconveniences that gasoline vehicles have. It's always stuff like "EVs suck because it takes 11 days to build a fast charging station, but don't bother checking into how long it takes to build a gas station!" or "EVs suck because batteries are flammable (Ed: even though most EV battery types aren't particularly flammable), but don't bother asking about the flammability of gasoline!" or "EVs suck because batteries are heavy and bulky, but don't bother asking about the weight and size of internal combustion engines vs. electric motors!" or "EVs suck because batteries are toxic (Ed: Actually, most types nowadays have little toxicity), but don't bother asking about the toxicity of the several tonnes of gasoline the average driver puts into their car every year, their filling spills and fumes, their oil leaks, etc, and the massively dirty industry that produces all this!" Etc.

I don't get these people.

Comment: Re:We get cancer because we have linear DNA (Score 1) 171

by jd (#47726213) Attached to: New Research Suggests Cancer May Be an Intrinsic Property of Cells

That's easy to fix. If a cell has not just the existing error correction codes but also digital ones as well, then mutagenic substances (of which there are a lot) and telemere shortening can be fixed. Well, once we've figured out how to modify the DNA in-situ. Nanotech should have that sorted soonish.

The existing error correction is neither very good nor very reliable. This is a good thing, because it allows evolution. You don't want good error correction between generations. You just want it in a single person over their lifespan, and you want it restricted so that it doesn't clash with retrotranspons and other similar mechanisms. So, basically, one whole inter-gene gap/one whole gene protected by one code. Doable. You still need cell death - intercept the signal and use a guaranteed method.

Comment: Exploit that which you cannot defeat (Score 1) 171

by jd (#47726171) Attached to: New Research Suggests Cancer May Be an Intrinsic Property of Cells

Here, in the year Lemon Meringue, we decided to solve the problem once and for all.

Instead of trying to kill cancer, we hijack its techniques. We start by having nanocomputers in the vaccuelles of each brain cell. These keep a continuous backup copy of the state of the brain up to death. Cancers disable the hard limit on cell duplication that cannot otherwise be avoided. By using the techniques of cell-devouring microphages, the cancer "consumes" the old cells and replaces them with new ones. They can't spread anywhere else, because that's how the cancer is designed to spread. Once the body has been fully replaced, the cancer is disabled. The brain is then programmed by the nanocomputers and the remaining cells are specialized by means of chemical signal.

This does result in oddly-shaped livers and three-handed software developers, but so far this has boosted productivity.

Comment: Re:It's not a kernel problem (Score 1) 682

by jd (#47726057) Attached to: Linus Torvalds: 'I Still Want the Desktop'

The free market didn't provide alternatives. The free market created Microsoft and the other monopolies. Adam Smith warned against a free market.

The majority do not create alternatives, either. The majority like things to not change. The familiar will always better the superior in the marketplace.

Alternatives are created by small groups of people being disreputable, commercially unproductive and at total odds with the consumer. These alternatives will typically take 7-14 years to develop. Adoption will typically reach peak after another 7-14 years. By the 30th year after first concept, the idea will be "obvious" and its destiny an "inevitable consequence" of how things are done.

In reality, it takes exceptional courage and a total disregard for "how things are done". 7-14 years with guaranteed losses is not how the marketplace works. Even thinking along those lines is often met with derision and calls of "Socialism!" by the market. No, real inventors are the enemy of the free market.

If you want a Linux desktop, you must forgo all dreams of wealth. You must subject yourself to the abject poverty that is the lot of an inventor in a market economy, or move to somewhere that supports the real achievers.

Comment: The problem isn't X. (Score 1) 682

by jd (#47725933) Attached to: Linus Torvalds: 'I Still Want the Desktop'

The problem is corruption. OSDL were working on a Linux desktop environment, but a key (financial) figure in the organization worked hard to kill off success and left around the time the unit went bankrupt. Several organizations they've been linked to have either gone belly up or have suffered catastrophic failure.

I won't name names, no point. What is the point is that such people exist in the Linux community at all, parasites that destroy good engineering and good work for some personal benefit of their own.

X is not great, but it's just a specification. People have developed Postscript-based GUIs using it. It's merely an API that you can implement as you like (someone ported it to Java) and extend as you like (Sun did that all the time). The reference implementation is just that. Interoperability of just that set of functions used by Glib/Gtk and Qt would give you almost all the key software.

Alternatively, write a GUI that has a port of those three libraries. You could use Berlin as a starting point, or build off Linux framebuffers, or perhaps use SDL, or write something unique. If it supports software needing those libraries, then almost everything in actual use will be usable and almost everything written around X in the future will also be usable. If what you write is better than X, people will switch.

Comment: Re:Nobody else seems to want it (Score 1) 682

by jd (#47725801) Attached to: Linus Torvalds: 'I Still Want the Desktop'

Binary drivers exist and are loadable so long as they are properly versioned.

Block drivers can always use FUSE.

Automatic builders can recompile a shim layer with new kernels (or even the git tree version), automatic test harnesses or a repurposed Linux Test Project can validate the shim. You don't need to validate the driver for everykernel, if it's totally isolated from the OS and worked before then it'll remain working.

Automated distributors can then place the binaries in a corporate yum/apt repository.

What has an ABI got to do with it? Only gets in the way of writing clean code.

Comment: Why? (Score 1) 682

by jd (#47725719) Attached to: Linus Torvalds: 'I Still Want the Desktop'

The commands to the bus don't change.
The commands sent to the hardware don't change.
The internal logic won't change.

That leaves the specific hooks to the OS and the externally visible structures.

Nobody is insane enough to use globals directly and structures are subject to change without notice. So external stuff will already be isolated.

If the hardware is available for any two of HyperTransport, PCI Express 2.x, VME/VXI or one of the low-power busses used on mobile hand-warmers, err, smart devices, then the actual calls to the bus hardware will be compartmentalized or go through an OS-based abstraction layer.

So 95% of a well-written driver is OS-agnostic and the remaining 5% is already is isolated.

So either drivers are very badly written (which is a crime against sanity) or the hardware vendor could place the OS-dependent code in its own DLL at bugger-all cost to them. Since the OS-dependent code has nothing trade secret in it, they can publish the source for the shim at no risk. Since the shim isn't the driver, there's no implication of support for OS' they don't know or understand. It's not their problem what the shim is used for.

Everyone's happy. Well, happier. The companies don't get harassed, the Linux users get their drivers, Microsoft gets fewer complaints about badly-written drivers killing their software. It's not open, it's not supported, but it's good enough.

Comment: Re:Fire (Score 2, Interesting) 141

by Rei (#47718877) Attached to: How Argonne National Lab Will Make Electric Cars Cheaper

Nuh uh! There are also compressed air cars - they only explosively decompress upon tank failure! ;)

At least with batteries, flammability or explosiveness aren't a fundamental requirement of how you're trying to propel the vehicle, just an unfortunate side effect of some variants of the technology (even not all types of li-ions are flammable). There's lots of people who assume that flammability is a consequence of electrical energy density, but that's just not the case. The actual charge/discharge lithium batteries via intercalating into the anode or cathode is more an atomic-scale equivalent of compressing air into a tank, you're having little affect on the substrate flammabilities and you're not even changing their chemical bonding, you're just cramming lithium ions into the space between their atoms. The flammabilty of some types comes from side effects, such as flammable electrolytes or membrane failures leading to lithium metal plating out; these aren't a fundamental aspect of the energy storage process.

Now, li-air, that involves an actual lithium metal electrode, and that is fundamentally flammable. Of course, so is gasoline. I have no doubt that they can reduce fire risks on li-air cells and keep them properly contained to prevent failure propagations. My bigger issues with li-air are its terrible efficiency, lifespan, and cost. I'm certain the latter would come down, and I expect that they can improve the lifespan, but I'm a bit uneasy about how much they can improve its efficiency. Right now, they're as inefficient as a fuel cell. : Who wants to waste three times as much power per mile as is necessary?

Comment: Re:non sequitur? (Score 1) 141

by Rei (#47718833) Attached to: How Argonne National Lab Will Make Electric Cars Cheaper

It is a non-sequiteur. The energy density of a li-ion battery doesn't even approach the theoretical maximum storage for the element lithium shifting between ionization states. That's hardly the only way this article is terrible, mind you. My head hurt every time they said the word "efficiency", it's like they were using it to mean everything possible except for actual efficiency. And if I read it right - who knows, the article is such a total mess - the researcher isn't talking about reducing battery cost, but increasing longevity. But maybe that was mangled too.

"If I do not want others to quote me, I do not speak." -- Phil Wayne