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Comment Re:Silly. (Score 2) 73

Even if battery energy density started getting close to that of liquid hydrocarbons, and thats a looong way off still, youd still need more batteries than you would fuel because batteries dont get lighter as they discharge like burned fuel does, rocket equation stuff. A 747 carries ~150k kilograms of fuel, if that didnt burn off thats an extra 37k kg the first quarter of the flight, an extra 75k kg the first half of the flight and so on...

Battery planes may never make widespread sense, if we ever start generating enough carbon free energy cheaply enough and even if all ground transport goes battery electric or whatever, at some point it might still be worth it to just make carbon neutral jet fuel with air fuel synthesis. That seems closer on the horizon than the battery tech needed for large planes to be feasible, hard to beat jet turbines for that application.

Comment Re:I want to see inexpensive plugin hybrids but .. (Score 1) 135

You might want to read up on how current hybrid vehicles actually work, 'cause it seems you have more than one misconception going on.

I have. For instance, my latest vehicle is the Ford F-159 XLT,, the full-hybrid model of the F-series pickup truck line. Power train is:
  - 6 cylinder dual-turbo engine. (runs low power but approoximately doubles output when a lot is needed.)
  - 47 HP motor-generator "pancake" on the engine side of the ttransmission, to scavenge / return power to./from a 1.5 kWhr lithium battery.
  - 10-speed automatic transmission, working with the lithium battery;s main alternator to fine-tune match the engine/mogen to the current driving situation. Max power of engine plus hybrid mogen; 430 hp.
  - full four wheel drive.

So it's primarily a gas-engine power train with an electric-car motor mechanically coupled to the engine shaft. Many other hybrids, from the venerable prius onward, are similar, with plug-in variants having a big scavaging/peaking battery good for pure electric operation of tens of miles rather than a minute or so and a wall-powered charger added.

What I'm looking for is essentially a pure electric - totally electronic "transmission" consisting of alternator(s) between the batteries and the motor(s), plus a tiny engine-generator able to burn gas and feed some teens of KW of charging power into the batteries when running down the road or parked near it.
 

Comment cobalt chemistry, not so nice. (Score 1) 115

Do the Waymo batteries use one of the lithium chemistries including cobalt, or a non-cobalt chemistry such as lithium iron phosphate?

Cobalt chemistries have a higher power/weight and energy/weight ratio, which made them the go-to chemistries for vehicle batteries. But they also produce oxygen when the cells overheat, leading to an unextinguishable runaway fire hazard: A burning cell makes enough heat to ignite the adjacent cells, so the whole assembly of them goes. Bad enough when it's a car's worth, but a disaster if it's a shipping-container sized module of a utility energy storage site. (And even worse when the site is a building full of racks, which someone had "protected" from fire with water-spraying, equipment-shorting system, so the whole site burns up, as happened recently with one in California creating a toxic mess.)

That's why purpose-built stationary lithium energy systems use non-cobalt chemistries - heavier, but a shorted cell just kills itself without getting hot enough to light off its neighbors.

Comment I want to see inexpensive plugin hybrids but ... (Score 1) 135

I want to see inexpensive plugin hybrids.

But not like the current ones, which are primarily an engine/tranny powertrain with a motor/generator + small battery for scavenging downhill/braking energy for later accelleration/uphill/cruise/power-boost.

I want ones that are primarily a battery-electric with a small aux engine-generator (say 15-20 HP range), big enough to power crusing with a bit left over for gradually charging. That would let you range-extend by the size of your gas tank plus fillups (i.e. indefinitely if only gas is available) or go from battery empty to back on the road in a couple tens of minutes.

The backup engine would only run at max-efficiency speed and could use an atkins-like cycle (see "liquid piston engine") to get the max power out of the fuel. Most operation would use power-grid charging (when available and cheaper than fuel).

Comment Re:Capitalism wins again. (Score 1) 207

Which is why it gets ridiculous. You can build an oven with a few conveniently shaped rocks. You can build an over with raw river clay, then use that oven to make better bricks, then use those bricks to make a better oven, which you can use to make even better bricks.

So, all it takes to turn somebody into a greedy capitalist exploiter is...the ability to stack rocks into a box with an opening.

Comment Re:Happily ever after (Score 2) 207

Rural ISPs often wire up farms as a core part of their business. I remember when Cambium released a firmware that allowed for the Canopy series of fixed wireless broadband gear that allowed for a CPE to slowly physically move, doing all of the re-ranging and what not to allow it to be, to a very small extent, mobile. Why? So that an SM could be mounted to a tractor.

It's also where you learn that corn silk really fucks up with 5 ghz RF.

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