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Comment: Re:That's not quick? (Score 1) 177

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) 177

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) 177

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) 177

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) 177

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) 177

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:AdBlock = Inferior + 'Souled-Out' vs. hosts... (Score 1) 544

by causality (#47722935) Attached to: Study: Ad-Free Internet Would Cost Everyone $230-a-Year
Incidentally I also use the Linux kernel feature called Transparent Hugepage Support. I set it to "Always" (as opposed to only when a program specifically wants it enabled). This is known to increase the memory footprint of applications, though by how much I couldn't tell you. The idea of this feature is: the operating system's memory allocator is gaining increased performance ("This feature can improve computing performance to certain applications by speeding up page faults during memory allocation, by reducing the number of tlb misses and by speeding up the pagetable walking") at the cost of higher memory usage.

Just thought I'd mention that since it may be relevant.

Comment: Re:AdBlock = Inferior + 'Souled-Out' vs. hosts... (Score 1) 544

by causality (#47722871) Attached to: Study: Ad-Free Internet Would Cost Everyone $230-a-Year

* Addons slowup slower usermode browsers layering on more - & bloat RAM consumption too + hugely excessive cpu use (4++gb extra in FireFox https://blog.mozilla.org/nneth... [mozilla.org])

That this can happen, I do not dispute. But I believe the case for it is being severely overstated by people who *ahem* have a vested interest in promoting alternatives to browser add-ons.

I currently run Firefox with 24 addons installed and actively enabled. This is mostly for ad-blocking and privacy-enhancing, with a few miscellaneous add-ons like one that restores the old-style Stop button behavior (stops animated GIFs as well as page loads). Since you seem to appreciate bold: there is no slowdown or latency problem that I can subjectively notice. If my addons are "slowing down the browser" they're doing it below the threshold of what a human can detect. I consider that a good and reasonable trade-off to make on my own systems.

On memory... I have 26 tabs open with a wide variety of sites loaded, many of which are content-heavy. This browser instance has been running continuously for many days. KSysGuard gives a nice breakdown of the memory usage of my Firefox process and this is the summary:

-----

Summary

The process firefox (with pid 5618) is using approximately 993.9 MB of memory.
It is using 971.4 MB privately, 15.6 MB for pixmaps, and a further 26.5 MB that is, or could be, shared with other programs.
Dividing up the shared memory between all the processes sharing that memory we get a reduced shared memory usage of 7.0 MB. Adding that to the private and pixmap usage, we get the above mentioned total memory footprint of 993.9 MB.

-----

Another section mentions that the 15.6MB for pixmaps may be stored on the graphics card's memory. At any rate, this is nowhere near 4+ gigs. Nor have I ever, with any version of Firefox, experienced anything remotely like 4GB of memory usage. This is a 64-bit system running a 64-bit Firefox that I compiled from source (your article mentions the memory penalty for Adblock is higher on 64-bit systems, which makes sense when you understand what that means). This system has 8GB of RAM installed, so ~994MB is negligible to me. For a little perspective, currently about 6GB is being used for buffers and disk cache, since this is what Linux does with memory that would otherwise be empty and therefore doing nothing. If I run a Windows game via WINE then that comes down to 4-5GB for buffers/cache since about another 1-2 gigs of memory becomes used.

Incidentally, I don't run Windows so I don't use your hosts file tool (and even if I ran Windows I'd probably rather roll my own, nothing personal). But I do use a comprehensive /etc/hosts file. I believe that good security is done in overlapping, interlocking layers. "Security" does not mean just remote attackers, but also anything intrusive I don't want, like advertisers and their tracking. I use an /etc/hosts file AND Adblock Plus, NoScript, Privacy Badger, Ghostery, and several others. What one of them alone does not catch, another one will.

Instead of viewing browser add-ons as an obstacle in your path to promoting your own solution, you could learn to work with them, use them effectively, and incorporate them into a multi-layered approach that includes all the work you've put into hosts files. Everyone would benefit that way, especially your users.

Comment: Re:$230 (Score 2) 544

by causality (#47722495) Attached to: Study: Ad-Free Internet Would Cost Everyone $230-a-Year

Don't get me wrong, DuckDuckGo sounds good. Sounds like they certainly don't actively track you. But I don't see them bragging that they "keep no data to hand over in the first place"

They don't use tracking cookies (their preferences cookies are not identifying, they're just a string of your options, if you've set them), so the most data that they can have for identifying you is the IP address. They've been SSL by default (redirecting from http to https and defaulting to https in search results where available, for example on Wikipedia) for a long time, so you don't suddenly jump into an unencrypted connection as soon as you leave.

It sounds much better than any other US-based search engine I'm aware of. But my own preference doesn't even log an IP address since 2009. You can also bookmark a URL generated with your preferences so there is no need to accept even preference cookies from them (and preferences include options like using POST instead of GET so search terms stay out of other sites' logs). And the aforementioned deal about being outside US jurisdiction is nice too.

DuckDuckGo also does not appear to offer to act as your Web proxy like Startpage will do. I rarely ever use this feature but it's nice that they would offer it. Startpage also offers the option to act as your proxy only for image/video searches, so other sites don't even get that data from you. This is what I like about them: they not only don't log and track you themselves, they also go out of their way to enhance your privacy against third-party sites.

I'm not knocking DuckDuckGo by any means; in my opinion it's good but Startpage/Ixquick is great. Yet, I think all of us benefit from having multiple privacy-conscious options available. Choice is a good thing.

Comment: Re:heh (Score 1) 544

by causality (#47721551) Attached to: Study: Ad-Free Internet Would Cost Everyone $230-a-Year

Local newspapers are the worst. My local newspaper give you ten free page views based on ip number and then locks you out.

Precisely because they are small and local, they probably wouldn't bother identifying TOR users. As a bonus you wouldn't be accessing this major multinational site where tens of thousands of others had the same idea and already got the exit node IPs banned.

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