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Comment: Total BS (Score 1) 554

by Maury Markowitz (#49793921) Attached to: How Tesla Batteries Will Force Home Wiring To Go Low Voltage

"To avoid the 20% to 40% power loss when converting from DC to AC"

The original author, Self, has exactly zero idea what he is talking about.

The power loss in a modern inverter like the one in the PowerWall is about 2%. On the panel side, efficiency of 95% is no longer considered competitive. The numbers he's quoting are decades out of date.

Comment: Re:Resistance (Score 2) 256

> Otherwise most of it is lost.

PFFT. The entire US electrical grid loses 7% of the energy fed into it. Most of those losses are in the last mile.

HVDC lines lose about 2.5% per 800 km and 0.6% in the end-point stations.

Read something before posting next time. Here:

http://www.siemens.com/press/pool/de/events/2012/energy/2012-07-wismar/factsheet-hvdc-e.pdf

Comment: Re:Question on EROEI (Score 1) 256

> Wind and solar = electricity. 98% of transportation is powered by oil

Today perhaps.

> Since 1kg of oil contains as much energy as 100kg of batteries, don't hold your breath

The differences is that in 5 years the oil will still have the same amount of energy, while the batteries will hold 25% more and cost 50% less.

> Besides, transportation is not just cars

True, but cars are half. If you remove half of that half you've gone an extremely long way to fixing a lot of problems.

Do some math, that's what it's for:

https://matter2energy.wordpress.com/2014/09/16/future-grid-energy-in-the-not-so-distance/

Comment: Re:Question on EROEI (Score 1) 256

> The practical solution is, of course, nuclear power

If you define practical like the rest of the world, that is, "cost effective", then this statement is demonstrably not true.

Modern nuclear plants have a CAPEX of about $8 and a CF around 90%. That is an effective production cost of $8.90

Modern wind turbines have a CAPEX of about $1.50 and a CF around 30%. That's an effective production cost of $5.00

So if your goal is to decarbonize the electrical supply, wind does it for a little over half the cost.

> Just wait until China and India

China's maximum planned buildout was to make about 1/2 the number of plants as the US to provide supply for four times the population. After the one-two punch of the 2008 Sichuan earthquake pointing out horrible safety violations in building and then Fukishima, these plans are on hold. Meanwhile, China installs more wind and solar than they ever planned for nuclear, about two to three times.

Comment: Re:Question on EROEI (Score 1) 256

> For electricity generation, oil (the fuel oil portion) is only used for peaking units, and
> from what I've seen the cost is significantly higher than natural gas peaking units

Oil fueled plants cost about twice the cost of natural gas peaking units.

http://www.lazard.com/PDF/Levelized%20Cost%20of%20Energy%20-%20Version%208.0.pdf

Page 2. GCC plans are *way* less expensive, but even they don't compete with wind any more.

Comment: Re:Umm, sure (Score 1) 202

by Maury Markowitz (#49671621) Attached to: Study Reveals Wikimedia Foundation Is 'Awash In Money'

"Anectodal evidence is hardly evidence, but"

There's no "but".

"While, truth be told"

It's not truth.

"Wikimedia Foundation is a honest and decent entity"

Undemonstrated rhetorical jibe.

"let other careless people"

Which "others"? The sample of two who you now denigrate?

"we need your donations to survive!"

Which is, by definition as a charitable organization, demonstrably true.

"they don't really mean what you think they mean."

They mean precisely what the *say*.

"Is that ok with you?"

Here: https://en.wikipedia.org/wiki/Logic

Comment: Umm, sure (Score 1) 202

by Maury Markowitz (#49663657) Attached to: Study Reveals Wikimedia Foundation Is 'Awash In Money'

"Yet millions of people continue to contribute, seeming to think that Wikipedia will "go offline" if they aren't given more donations."

Says who?

"Yet as a new Wikipediocracy"

Oh. So then the first quoted sentence should actually read:

"We imagine that bunch of people we invented so we could complain about the Wikipedia, which is the entire reason for the existence of our site, might think that donating is a good idea, which it is. We didn't conduct any sort of study or analysis, because that would take time away from writing additional whiny articles."

+ - Researcher Discloses Methods For Bypassing All OS X Security Protections

Submitted by Trailrunner7
Trailrunner7 writes: For years, Apple has enjoyed a pretty good reputation among users for the security of its products. That halo has been enhanced by the addition of new security features such as Gatekeeper and XProtect to OS X recently, but one researcher said that all of those protections are simple to bypass and gaining persistence on a Mac as an attacker isn’t much of a challenge at all.

Gatekeeper is one of the key technologies that Apple uses to prevent malware from running on OS X machines. It gives users the ability to restrict which applications can run on their machines by choosiing to only allow apps from the Mac App Store. With that setting in play, only signed, legitimate apps should be able to run on the machine. But Patrick Wardle, director of research at Synack, said that getting around that restriction is trivial.

“Gatekeeper doesn’t verify an extra content in the apps. So if I can find an Apple-approved app and get it to load external content, when the user runs it, it will bypass Gatekeeper,” Wardle said in a talk at the RSA Conference here Thursday. “It only verifies the app bundle.”

“If Macs were totally secure, I wouldn’t be here talking,” Wardle said. “It’s trivial for any attacker to bypass the security tools on Macs.”

Comment: Re:They should be doing the opposite (Score 3, Interesting) 309

> 10 years should be the norm. That is a fact.

Or less. The value of materials older than that is limited. There are, of course, counterexamples, but they are the exceptions to the rule. Something like 99.9% of all songs that receive any income do so in the first 18 months, and that number continues to shrink as the companies churn out pop.

But forget music, what about snapshots? Every selfie you take is covered for 70 years after you die. Clearly there is something very wrong with that.

Once it hits the fan, the only rational choice is to sweep it up, package it, and sell it as fertilizer.

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