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Comment: Re:Tesla DOES use laptop batteries (Score 1) 60

by sribe (#49607839) Attached to: Tesla Adds Used Models To Its Inventory, For Online Purchase

Except that Tesla (and Smarts, and the few other cars which use batteries manufactured by Tesla) use *the exact same kind* of battery cells as regular laptops (on purpose, because they are cheap and easy to source due to the economy of the scale at which they are produced).

No, they purchase custom cells. Being Lithium-ion, they are certainly similar, and Tesla does not publicly reveal what is custom, but they are not the exact same.

Comment: Re:Far too expensive for a used car (Score 2) 60

by sribe (#49606905) Attached to: Tesla Adds Used Models To Its Inventory, For Online Purchase

They are super expensive, and I have yet to see any battery tech that lasts over 4 years, and normally it is performing far worse than optimal at a fraction of that time.

Actual tests on actual used cars (by Consumer Reports) demonstrate that what you say is unequivocally wrong for the batteries used in EVs and hybrids. No, the ones in our notebooks and phones don't last so long, because size and weight are more important than lasting 10 years. Cars are designed differently, for different longevity/size/weight tradeoffs than are portable electronics.

Comment: Re:One word: Cloud (Score 2) 237

It's NOT trying to burn the school down. That's the act of an adult, 15 years old or not.

But he DID NOT try to burn the school down. He did something stupid and childish, which could have burned the school down only if he had been extremely unlucky--huge difference, and judgmental pricks like you who like to conflate what "could have happened" with what "he tried to do" in order to justify your self-righteous and indignant attitudes, who are responsible for the epidemic of ridiculous zero-tolerance policies in schools.

Comment: this is actually cool (Score 3, Informative) 505

by sribe (#49593405) Attached to: Tesla Announces Home Battery System

On the prior article before the announcement, I posted about the economics not being that compelling, using my own actual numbers for consumption and peak vs off-peak pricing. I also noted that in some states, CA in particular, when peak pricing is ~60% higher than where I live, that it could start to be somewhat attractive.

That was all based on the pre-announcement rumored price of $13,000 for 10KWh. At $3,500 for 10KWh, I'd be looking at a 4-year payback, or, in other words, about a 25%/year ROI. To be clear, that's without solar PV panels to generate electricity, that's strictly charging the battery during off-peak hours and then running the house on it during peak hours. (Quick calculation based on battery price alone; total installed system more likely to see 15%-20% ROI, but still, not bad.)

I had wondered what Musk was up to and if the rumors were correct. Because you can already buy a 10KWh nickel-iron battery system for $13,000, so it did raise the question of what was the point? Well, now we know the point--1/4 the cost of existing competitive systems.

One big question not answered by the linked article, is what technology is used and what's the depth of discharge without damaging the battery. With nickel-iron, you can discharge most of the charge safely. With lead-acid technologies, you can't go below about 70% without shortening the lifespan. So 10KWh can actually mean anything between 3KWh and 8KWh of usable power--a huge range. (Hey, maybe Tesla's going to be consumer-friendly here--maybe 10KWh means 10KWh of usable power... As this kind of thing becomes more common in the home, it would make sense to rate battery systems that way, to make direct comparisons easier...)

Comment: Re:Kickstarter seems like a bad deal to me. (Score 2) 29

by sribe (#49579639) Attached to: Armadillo Aerospace Resurrected On Kickstarter By the Team Members

For example, if I donated some money to Exos Aereospace above and they developed a revolutionary rocket that makes the founders billions, why can't the people that donated have a slice of the pie?

SEC regulations. There's a high bar, in terms of regulations and documentation, for selling equity to the general public.

The SEC is actively working on reducing the burden precisely to allow small investments via crowdfunding, but I haven't followed their progress.

Comment: Re:Does it matter? (Score 2) 52

by sribe (#49569129) Attached to: TeslaCrypt Isn't All That Cryptic

Since most people who will be subject to ransomware have no way of knowing the mechanics of the encryption (or wouldn't be able to access it anyway) ... does that they lied about their super secret crypto make a damned bit of difference?

Well... IF the tool becomes widely-enough known, that when a victim goes looking for some tech to help them, then it could be very useful. As opposed to real public/private key encryption where no one could legitimately help them.

I doubt this will happen; I doubt the tool will be utilized; but it's at least been made possible now. (And of course, new versions of the malware will keep popping up...)

Comment: big deal (Score 2) 299

by sribe (#49550509) Attached to: Tesla To Announce Battery-Based Energy Storage For Homes

So, for $13,000 up front, I can save at most about $80/month, maybe less, depending on the particular battery technology and how deeply the batteries can be safely discharged. (Yes, I used actual numbers.) It's a first step, but assuming that the capacity is 10KWh as mentioned in earlier articles, it's not really any cheaper than existing solutions. Now maybe Tesla will ramp up capacity and make them more available, or maybe it will actually be higher capacity, or maybe the price will come down substantially as volume increases. Because at 1/2 the $/KWh it would start to be really interesting, but right now, it's kind of marginal--at least for me at ~$0.15/KWh peak; obviously, in a state, CA for instance, where peak power prices are higher, the economics are better.

Comment: Re:Progressive Fix 101 (Score 2) 622

by sribe (#49529051) Attached to: Cheap Gas Fuels Switch From Electric Cars To SUVs

All in all, every time I see an SUV on the road I have to assume that the driver is a huge jerk, because only a huge jerk would choose to endanger other people's lives just for the sake of their comfort and convenience.

Well, maybe that's kind of true in San Fran... But there are places (and times) in the world that when you see a Prius, you should assume that the driver is a total moron...

1 Mole = 007 Secret Agents