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Comment: Re:That's not quick? (Score 1) 174

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) 174

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) 174

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) 174

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) 174

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) 174

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:Fire (Score 2, Interesting) 142

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) 142

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.

Comment: Light but reactive element = high energy density (Score 1) 142

by Ungrounded Lightning (#47718377) Attached to: How Argonne National Lab Will Make Electric Cars Cheaper

"lithium is in the upper left-hand corner of the periodic table. Only hydrogen and helium are lighter on an atomic basis."

  I'm wondering if this is a non sequitur for electric batteries.

Not a non sequitur at all.

An important factor for batteries is energy density: How much energy is stored per unit mass. This is particularly important for electric cars: The higher the energy density, the less mass you havce to haul around for a given amount of "fuel", which means the less "fuel" is spent hauling your "fuel" around, so it's a more-than-linear improvement.

Lithium is both extremely light and a very reactive nonmetal. So you're talking about a lot of energy per unit mass for the lithium-based electrode's contribution to the reaction.

Comment: Re:Ready in 30 years (Score 5, Interesting) 301

by Rei (#47708629) Attached to: If Fusion Is the Answer, We Need To Do It Quickly

You're arguing against Tokamak fusion. But what about, say, HiPER? Looks to me to be a much more comercializeable approach, yet it's still "mainstream" fusion, just a slight variant on inertial confinement ala NIF to make it much smaller / cheaper / easier to have a high repeat rate (smaller compression pulse + heating pulse rather than a NIF-style super-massive compression pulse). The only really unstudied physics aspect is how the heating pulse will interact with the highly compressed matter; NIF and pals have pretty much worked out the details of how laser compression works out. Beyond this, pretty much everything else is just engineering challenges for commercialization, such as high repeat rate lasers, high-rate hohlraum injection and targeting, etc.

I've often thought (different topic) about how one can get half or more of fusion's advantages via fission if you change the game around a bit. Fusion is promoted on being passively safe (it's very hard to keep the reaction *going*, it really wants to stop at all times), it leads to abundant fuel supplies, and there's little radioactive waste (no long-term waste). But what about subcritical fission reactors? Aka, a natural uranium or thorium fuel target being bombarded with a spallation neutron source. Without the spallation neutrons, there's just not enough neutrons for the reaction, so the second the beam gets shut off, the reactor shuts down, regardless of what else is going on. It'd be a fast reactor, aka a breeder, aka, your available fuel supplies increase by orders of magnitude. And your long-term waste would be much, much less in a well-designed reactor. Spallation neutron sources have long been proposed as a way to eliminate long-lived nuclear waste by transmuting it into shorter-lived elements.

Comment: Re:How many years could he be charged with? (Score 1) 297

by Rei (#47702193) Attached to: WikiLeaks' Assange Hopes To Exit London Embassy "Soon"

Wrong, you're talking about charge 2 on the EAW, which is only a molestation charge, not rape. charge 4 on the EAW is the rape charge and concerns a different woman. All of the charges are:

1. On 13th – 14th August 2010, in the home of the injured party [name given] in Stockholm, Assange, by using violence, forced the injured party to endure his restricting her freedom of movement. The violence consisted in a firm hold of the injured party’s arms and a forceful spreading of her legs whilst lying on top of her and with his body weight preventing her from moving or shifting.

2. On 13th – 14th August 2010, in the home of the injured party [name given] in Stockholm, Assange deliberately molested the injured party by acting in a manner designed to violate her sexual integrity. Assange, who was aware that it was the expressed wish of the injured party and a prerequisite of sexual intercourse that a condom be used, consummated unprotected sexual intercourse with her without her knowledge.

3. On 18th August 2010 or on any of the days before or after that date, in the home of the injured party [name given] in Stockholm, Assange deliberately molested the injured party by acting in a manner designed to violate her sexual integrity i.e. lying next to her and pressing his naked, erect penis to her body.

4. On 17th August 2010, in the home of the injured party [name given] in Enkoping, Assange deliberately consummated sexual intercourse with her by improperly exploiting that she, due to sleep, was in a helpless state. It is an aggravating circumstance that Assange, who was aware that it was the expressed wish of the injured party and a prerequisite of sexual intercourse that a condom be used, still consummated unprotected sexual intercourse with her. The sexual act was designed to violate the injured party’s sexual integrity.

Please follow the case better if you wish to comment about it.

Comment: Re:How many years could he be charged with? (Score 1) 297

by Rei (#47702177) Attached to: WikiLeaks' Assange Hopes To Exit London Embassy "Soon"

Once again, Assange fanboys go all out to dismiss the rape charge against him without even knowing enough about it to even keep the two women involved straight.

There are two women involved here: AA and SW (and no, their names haven't been scrubbed, but it's a sick testament to our society than rather than letting justice run its course, everyone wants to lead a personal witch hunt against the accusers, and I certainly won't help enable it). AA is the one who tweeted (but not what you said she tweeted) and who has been to cuba and wrote a blog (which doesn't say what you say it said). SW is a low-level museum worker who did none of the above. The rape charge only applies to SW. There are no rape charges concerning AA, only three lesser charges - 1x unlawful sexual coersion and 2x molestation.

The fact that you don't know even this most fundamental basic aspect of the case yet want to pontificate about it speaks volumes as to how much you are just willing to assume the innocence of Assange and that the women are just lying sluts trying to set up an innocent man. Which always happens with famous people and their fans. When you hear people talking about "rape culture", that's a very big part of it.

Now, let's correct your misrepresentation of the facts in detail.

1) There are no rape charges concerning AA. She described a series of unpleasant experiences, first to friends, later to police, involving the pinning of her down to try to force sex, her consent in exchange for the use of a condom which she feels he deliberately broke, and his repeated acts at later periods such as rubbing his naked genitals against him after she had told him no. She became so uncomfortable around him that she moved out of her own apartment to avoid him. The events therein form the basis of the unlawful sexual coersion and molestation charges. The tweet in question was not "Julian is FANTASTIC", it was "Sitting outdoors at 02:00 and hardly freezing with the world's coolest smartest people in the world". She was at a party full of political activists, one of the people there being Julian. At the same party, according to testimony collected by the police, she warned a friend about Julian.

2) She did not file a rape complaint. All of the testimony speaks to that she went to the police to support SW in her going to the police to report a rape by bringing up what Julian had done to her. Which is only what a person would expect. SW had already at that point, according to testimony, been telling friends and family that she'd been raped by Julian. SW's goal in going, however, was not prosecution but to try to force Julian to take an STD test. AA's blog (again, NOT SW, who the rape charge is about) entry was something she copied years ago from someone else about how to break an ex boyfriend up with his new girlfriend, and the first two rules basically sum up as "don't do it". And seriously, do you honestly think if millions of fanboys combed through everything you've ever written on the net that they couldn't find something to attack your character with?

3) See my reply to the post above yours, and pay particular attention to the fact that the Svea Court of Appeals has already reviewed all evidence in a full court hearing with testimony from Assange's attorneys and ruled against him, and the Swedish Supreme Court refused Assange's appeal.

4) How does a person "convince" a person of anything while they're asleep? Is Assange capable of doing Inception?

5) Again, you're talking about AA, not SW. The attacks against AA are the most ridiculous six degrees of separation thing I've seen in ages. It's something penned by Israel Shamir, a famously misogynistic and antisemitic author, as well as being the guy who's famous as being the person who gave unreleased Wikileaks information to the dictator of Belarus which he then used in a purge of political opponents (google "Israel Shamir" and "Belarus"). The argument he posted on Counterpunch basically goes like this: AA once wrote articles in support of democracy in Cuba for a journal, and that journal was run by a group, which is connected to another group, which is connected to another guy, that a Wordpress blog says is a CIA agent; and that the group she worked with a women's rights/democracy group in cuba which is connected to a group in Miami that once held a parade that a guy who tried to blow up a plane in Cuba marched in (Maria Carey marched in the same parade). Wow, I'm sold, clearly a CIA agent! And let me guess: the CIA planted SW as a low-level museum worker afraid of unprotected ages ago because their CIA psychics forsaw the day when there would be a guy named Julian Assange who would find her attractive and sleep with her unprotected?

"The trouble with doing something right the first time is that nobody appreciates how difficult it was." -- Walt West