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Comment Re:Megawatt (Score 1) 275

The skin effect works on everything.

[citation needed]

And I would bet in DC it is far worse than in AC.

[citation needed]

One of the reasons HVDC is becoming more popular for power transmission is due to it not having to deal with the skin effect.

The skin effect happens because all electrons are negatively charged. They repel each other and wander to the outside of the conductor to find an equilibrium of repelling forces.

Has absolutely nothing to do with AC/DC or the frequency of AC, you are mixing something up.

That's...not how the skin effect works. The skin effect definitely depends on frequency. Please see the link I referenced earlier.

It sounds like you're referring to some other concept. Could you please provide some sort of link or citation explaining it, because it's definitely not the skin effect.

Comment Re:Megawatt (Score 1) 275

Interesting. I'd be very curious to see any literature describing this effect. Don't get me wrong, I'm not disagreeing -- I'm aware that the resistance of many metals used in wires increases with temperature, and the center of a conductor would have a higher temperature than the outside surface of the conductor, so that checks out theoretically -- I've just never heard of it being a significant concern for high-current DC in regards to conductor design and that sounds interesting.

Comment Re:Megawatt (Score 5, Informative) 275

For high voltage most of the current will move along the skin of your conductor, so you are much better off increasing the total surface area of the skin by using multiple bundled conductors

You're thinking of the skin effect applies to conductors carrying high-frequency (not high-voltage) electricity.

DC circuits of whatever voltage are unaffected by the skin effect, and EV fast charging is essentially exclusively DC.

Comment Re:huh (Score 2) 49

I also really like that one can add a "recovery record" (error detection/correction data to correct for bitrot or other errors) during archive creation and that record is integrated into the single archive file. While other options exist (e.g. using PAR2 files that are separate from the archive), I find them a bit clunky. Having everything in a single archive managed by a single program is nice.

Also, I've used WinRAR for decades and the user interface is familiar to me. That's a big factor.

Comment Re: PG&E is its own disaster. Where was Tesla? (Score 5, Informative) 135

The Tesla virtual power plant (an aggregation of all participating Powerwalls) was producing about 20-25 MW from a few thousand installations.

Source: mine was one of them and they reported the stats for both ones individual installation and for the system as a whole.

Comment Re:They need to offer an alternate free conversion (Score 1) 46

For what it's worth, I moved off of my grandfathered free Google "Workspace" account several years ago and switched the mail/calendar/contacts service to Fastmail. It took a few weeks for the spam filter to get trained properly to my incoming mail, but since then it's been damn near perfect. No complaints at all from that front. I've been very satisfied with the mail service, price, and the clueful employees they have.

Comment Re: I wonder if it is this... (Score 1) 117

Exactly correct. Itâ(TM)s the GPS rollover + a manufacturer specific offset.

There was some concern a few years ago when some GPS-disciplined oscillators used as time and frequency standards in common use among the âoetime nutâ community were coming up on their specific rollover. The devices were obsolete and no new firmware was available, but the community updated the various software that processes data from the devices in time and all was well.

It seems things were handled less well by Honda.

Comment Re:Resulting QR Code is invalid (Score 1) 167

Invalid, or simply containing information that most QR code readers cannot read?

My understanding is that it contains binary, digitally-signed information that can prove to certain compliant QR code readers that the information is authentic and unmodified. Such scanners would presumably be used at public fora like stadiums, airports, etc.

Comment Re:Here's why "vaccine passports" are a flop (Score 1) 167

Personally, I'm wondering if it's a HIPPA violation for people to request this information for entry to a public forum like a stadium. Has anyone challenged these vaccine passports in court yet?

That's not how HIPAA works. HIPAA applies to health-related entities (e.g. health insurers, providers, etc.), and limits such entities from sharing one's health information without authorization. Employers and public fora like a stadium are not covered by HIPAA and so they can request proof of vaccination from the employee (the employee can share their information as they see fit, as they're not restricted by HIPAA), as well as requesting it from their healthcare provider (but the healthcare provider would violate HIPAA by sharing it without the employee's authorization).

See https://ancillary-proxy.atarimworker.io?url=https%3A%2F%2Fwww.hipaajournal.com%2Fi... for details.

Comment Re:I tried yours, it works (Score 2, Informative) 167

It should be pretty scary that this information is provided to ANYONE with so little input.
Why is government even making my medical information public?

It's not and it isn't.

They ask you to provide your name, birthdate, and phone number or email address you provided when you were vaccinated, as well as a PIN. The system checks their records and if the phone number/email you provided matches their records, they send you a text or email with a link. You open the link and your information is only showed if you provide the PIN you entered in the first step.

This means that they only send the information to a phone or email that you already provided during the vaccination process and only show the information to someone who demonstrates they have access to that phone number or email (by virtue of clicking the link sent only to the phone number or email address) and that the person who controls the phone number or email address is also the person who made the request in the first place (by verifying the PIN). You can then save or screenshot the information and QR code to your local device and display it only to people you choose.

The link expires after 24 hours (but you can request a new one if desired) so only you have the ability to share or not share it as you please.

Comment Re:Not a great idea... (Score 1) 168

I agree. Last year I took a drive with my family in our Bolt EV from our home in Alameda County, CA to Lake Tahoe. The town of Colfax, CA had some typical highway gas station stops with some fast food places right off the highway and an EVgo fast charger a few blocks further into town by the old historical railroad station. Plugging in at the charger, we went into a local pizza place, had some tasty food and drink, used the restroom, and were done about 45 minutes later just as the fast charger was finishing up charging the car.

Colfax is a bit over 2 hours from where we started so it made sense to stop, use the facilities, and get a bite to eat. Charging up was a bonus that fit perfectly with that schedule.

Had we needed to hang out at a bare-bones "gas station"-type location with little facilities for the duration, that would have been less pleasant than a nice, local restaurant or someplace like a full-service highway rest stop with a few restaurants, a place to get out of the weather, etc.

I'd like to see more local stores and places with parking lots put in Level 2 chargers for drivers to charge their vehicles while shopping and eating, and put Level 3 fast chargers in more rest stop-type areas.

Comment Re: People are afraid of change... (Score 1) 168

Right. All you need is a nice suburban house with a big garage and a $8,000 EV charger to go along with your $60,000 Tesla and you are all set!

That's marvelous except you don't need any of those things.

Quite so. Even if you don't charge up from a regular outlet but instead want a Level 2 charger, a ClipperCreek HCS-40P (the charger I have) is less than $600 and is built like a tank. Installing it took about $100 worth of 6 AWG wire, a 40A breaker, a $13 50-amp outlet, and about two hours to do it myself to code. My friend recently had a local electrician put in the outlet, breaker, and wiring and it cost $400 for parts + labor. Hardly an unbearable expense, plus it's one-time.

electric cars are not perfect but people sure like inventing problems.

Agreed. Yes, there's absolutely many likely scenarios where current EVs aren't terribly practical (like people who park on the street, don't have a garage, need to haul heavy loads great distances, etc.) aren't really the greatest choice. But there's plenty of scenarios where they make a ton of sense -- I plug in my car in the garage once or twice a week after work, it waits until the power rates change to cheap off-peak costs, then it starts and is fully charged by morning. Easy. My wife, on the other hand, drives a gas car and needs to spend 10-30 minutes every week or two at Costco waiting in line to buy gas.

Comment Arq (Score 1) 283

For years, I used CrashPlan Home for Windows (and happily paid for their cloud storage). I really liked the ease of setting up computer-to-computer backups, as well as computer-to-cloud backups. It never failed during a restore, and generally worked well. However, they discontinued their home offering several years ago, so I had to switch to an alternative.

After trying several options, I ended up with Arq Backup. It's not free or libre, but it works reliably and well with a multitude of back-ends (I use Backblaze B2, OneDrive, and a local NAS), and has the standard encryption, compression, and deduplication features, as well as doing VSS snapshots. The licensing isn't the cheapest around, but it's not unreasonable and has discounts for those with multiple computers.

Arq5 was rock solid but could be slow (tasks were not done in parallel). Arq6 had a very rocky start (early versions borked the conversion of existing Arq5 backups) that put many people off. Arq7 has been rock solid as well (it can import and use Arq5 and Arq6 backups so no new data needs to be uploaded, with new data being stored in the Arq7 format, but doesn't convert existing to the Arq7 format).

I also considered Duplicati, but that has issues with VSS (it needs to run its service as admin to use VSS, but doesn't do this by default). Duplicacy is interesting, and has multi-computer deduplication. But both lack native user interfaces, and instead rely on clunky web-based interfaces.

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