If you can extract some energy then by definition it is not zero-point energy.

The regulatory approval for those is just too expensive in practice. I mean you blow up one star due to cost cutting and nobody trusts the tech ever again...

AA battery size is black holes. Can’t quite get the technology to scale for AAA so you still have to swap the TV remote.

Absolutely. No idea what’s going on with these downvotes.

Please don't respond to a bad comment by breaking the site guidelines yourself. That only makes things worse.

If you know more than others do, that's great! But please contribute by sharing some of what you know, so the rest of us can learn, rather than putting others down.

https://news.ycombinator.com/newsguidelines.html

How does someone with such short temper get to work in the aerospace industry? You know we are just a bunch of random strangers on the internet and telling someone to "sit down" just comes across as funny more than authoritative. And I don't think telling someone "I know exactly what the fuck I'm speaking of" has ever had the desired effect on the internet, it just screams insecure - if you're really an expert make it show through your words not by trying to intimidate people.

Heat pumps are best for small thermal gradients. If you want your room to be a nice 70F while it's 50F outside, a heat pump is a very efficient way of heating your room. If you want a blow torch that's hundreds of degrees above ambient, a heat pump is terribly inefficient. The exact cutoff where gas heating becomes more efficient is variable, but it's typically a temperature differential between 40 and 60F.

Completely separate conversation. I was responding to the statement "We can extract a lot more energy from fossil fuels in large scale plants".

No it wouldn't depend. Electricity generation and electricity transfer has losses. Gas transfer has loss only if there is a leak.

It does not follow that "We can extract a lot more energy from fossil fuels in large scale plants"

Not what I replied to

I don't know what more I can say to convince you that I'm not trying to put down the technology. I'm interested in it, that's why I think it's a shame to curse it with a used-car salesman marketing name.

As for wood batteries,

Most usage of the term 'battery' is independent of technology, outside of usually wanting electricity as the interface. The fact that most batteries people talk about happen to be electrochemical cells is incidental -- it's irrelevant to whatever they are actually talking about. So yes, a lot of the time 'battery' happens to refer to electrochemical cells, but it also refers to energy storage devices in general, which wood obviously is.

The problem with wood being a "solid-state battery" is surely the solid-state part.

Q: I mean how does that even work, solid-state combustion?

A: No, it's still obviously a normal chemical cell. You do a chemistry and these special "electrodes" turn the result into electricity.

Q: Can you recharge it?

A: Well, not in your own home, but in your backyard, maybe sort of.

If we are to use the term 'solid-state' to refer to anything that is solid, as in "solid-state battery", and we can get electricity from burning wood, I don't see the problem with referring to wood as a solid-state battery.

There is a nine box chart with x-axis of doctrine or how it is used and y-axis of structure; each axis has three values, purist, neutral and radical.

For the purist in doctrine and structure, wood is not a battery. If one is somewhere between neutral and radical, then wood is a battery that was built by its integrated disposable solar cells.

Maybe. Last I checked Ukraine preferred radio drones to fiber optic - the spool is heavy and a limitation in many ways (not all that I understand). Fiber optics are used only when you can't get something else to works. Advances in AI, radio relay systems, self-navigation, and anti electronic warfare are all things they are working on so they can use more drones without fiber. For longer ranges drones fiber is not an option and so they have no choice but use something else.

Where fiber optic is used though, that is the limit. That is a minority though.

For some uses in Ukraine that is true, but even there they are still using radio for many drones, and especially their longest range drones (100+km).

There's also payload and loiter time to consider.

If you have a drone that can watch the battlefield for hours instead of minutes that is incredibly useful. Same story if you have a drone that can 3x its payload.

Most Ukrainian drones don't use fiber optic I don't think. To deal with EW, they're favoring autonomous targeting/guidance for the final part of the strike.

Depends on the battle but yes. Even then the range is usually at least 10 km and starts to be limited by the size of the spool you're going to carry on the drone (though dealing with general cable issues over the distance is one of the reasons this type can't be used for everything).

Autonomous kamikaze drones don't need spools.

if it’s the same range for less weight you have more room for munitions and other gadgets

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It's an interesting discussion, because if you assume access to atmospheric oxygen, gasoline is MUCH more energy dense.

    TNT.....:  4 kJ/gram and  7 MJ/liter
 
    Gasoline: 43 kJ/gram and 33 MJ/liter

Energy capacity vs. energy release rate, or energy vs. power, tends to follow an inverse relationship, at least within similar domains.

The fuels which afford the highest rates of storage tend to release it more slowly. Chemical explosives typically have about 1/10 the energy storage capacity (by mass) of fuels, as several people have pointed out.

Similar relationships exist for other forms of energy storage. For electricity, fuel cells, chemical cells ("batteries"), flywheel / reaction storage, and capacitors tend to offer a trade-off between total storage capacity and reaction time. Capacitors can react at intra-phase rates (that is, within a single 60Hz power cycle), whilst batteries and flywheels can take longer to come online.

See for example: "Battery Parameters" <https://www.monolithicpower.com/en/learning/mpscholar/batter...>.

"Liquid gasoline does not have anywhere near the energy of TNT,"

Energy density of gasoline is approximately 44 to 45 megajoules per kilogram.

Energy density of TNT is approximately 4.184 megajoules per kilogram.

Gasoline isn't that explosive. You can shoot up a gas tank and it will just burn. What you see on TV is movie magic. Gasoline vapor can explode, but you need the right air to fuel ratio and a spark.

"Fast X: why cars don’t really explode when they crash"

"Petrol and diesel can only explode when under pressure and mixed with air and in the case of petrol, have a small amount of energy added in the form of a spark or a flame. Engines pressurise the fuel/air mixture in the cylinder and so produce small, confined explosions which turn a crankshaft and drive the wheels."

"When cars are involved in collisions, fuel lines are often torn and petrol leaks out onto a hot engine. Liquid petrol can catch fire in the presence of air. But it can’t explode because it’s not under pressure and is in the liquid phase rather than a vapour."

https://theconversation.com/fast-x-why-cars-dont-really-expl...

Bleach? What does that do?

My high-school crowd stopped just short of building a multistage FAE device. I left early for college and everybody else was short of cash, and that was the end of our neighborhood R&D program. All pre-9/11, needless to say. It's a lot less fun when the possible punishment goes from detention at lunch to waterboarding in Gitmo.

No it can't. To combust it needs ~ 500F. If you left it out uncovered in the open and allowed the it to vaporize with a spark nearby, it might explode, but thats not spontaneous combustion. Gasoline sitting in a sealed container wont spontaneously combust.

Gasoline doesn't do that. Perhaps you're thinking of the following?

What it does do is slowly polymerize, becoming useless as an ICE fuel in time, typically in a year or two. This is why backup generators should run on propane, which has no degradation mechanism.

> 10-kilo swappable battery packs

I like the way you think. Putting a meaningful amount of capacity in something luggable by an average human would open up a lot of possibilities. Not just for cars, but everything. Our battery powered future looks bright already, but this would be incredible.

> juicing 10 cars in 5 minutes has to require significant electrical infrastructure!

I believe it is becoming fairly common to use batteries as a buffer at fast chargers. The demand charges for bursting megawatts of power from the grid are apparently really steep, so it makes sense to put in a big battery and steadily draw a lower amount of power and then just charge cars from the battery.

If you can't charge at home it's probably because you're in an apartment, which means you're in a city, in which case there's going to be charging infrastructure.

Not only that, but with a longer range, you have more flexibility in planning recharging. It may take more time to top up from 50 km left to 500 km, but you have more flexibility about when to do it. Something that needs a daily charge is going to be interfering with your schedule.

"The reason is simple: The mere existence of low-range EVs hurts overall EV adoption, because people aren't going to rent a car just for a road trip. You're talking about adding $100+ per day on what's supposed to be a cheaper method of travel compared to flying."

Just wait for people to be priced out of ICE cars. EV's should be and will be significantly cheaper to buy and manufacture.

Tell that to my polestar 2 pls. and then come back again in the winter when it drops another 30% due to the battery heater energizing

This EV owner disagrees, and I imagine that city dwellers without dedicated charging agree

I would wager charging time is basically solved, adoption is only thing that's left.

Its a huge issue in cold climates.

Batteries are cheap enough to build (using a commercial installer completely kills the economics, because you're paying five to ten times the actual cost in the US) a reasonable size personal battery bank (~100+ kwh), paired with some overkill solar, to totally replace the grid in a lot of cases. GP isn't limited to rooftop solar with 1/3rd an acre, so they can do it quite cheap if they want.

It is actually the opposite, RTGs use plutonium-238, which is much more radioactive than the plutonium-239 used in bombs. And it is a problem because it will blow up before you can assemble enough of it to make a big nuclear explosion. In addition, it is not as fissile as plutonium-239.

I don't know about production, it is a hypothetical and I just assumed you had a bunch of plutonium-238 available, but as I understand it, rather than being an enrichment problem as with uranium-235/238, it is just not made using the same process as plutonium-239 to begin with.

Imagine for a moment that batteries with decent shelf lives are free.

You build a power plant on a geothermal vent in Iceland. The electricity it produces is plentiful and cheap. You run it full tilt charging batteries.

You ship those batteries to wherever you need cheap power, and send them back empty. This works with hydro, wind, solar, ...

Batteries do drive down energy costs because even ignoring transmission lines, they let you move energy in both space and time, pushing all energy costs towards the cost of the cheapest means of generation on its best day.

Definitely! However I frequently encounter people on energy discussion forums that assume that we need 2-3 months of battery storage, perhaps because they see natural gas or other storage and assume that batteries need exactly the same thing, so I'm perhaps overly eager to respond to claims about month-long battery storage.

I had previously been hopeful that battery storage would allow more shared used of land, but the fire risks of batteries have been pretty severe. And since the land usage requirements are fairly low, there's no need to enhance the risk by putting batteries, say, in enclosed spaces of former natural gas generation facilities [1].

I'm hopeful that we'll see a lot more storage, say a shipping container's worth, at the end of distribution feeders, which helps suck up residential solar with minimal resources, but solving the problem of "who pays for the benefits for all" when the utility is incentivized to keep grid costs high means that nobody is knocking down doors to make that happen...

[1] https://www.utilitydive.com/news/moss-landing-fire-battery-s...

There's an engineering tradeoff between having excess generation capacity, for that seasonal minimum, and having more storage. The cost optimal decision on that tradeoff will be determined by the ratio of excess generation cost and storage cost for rarely-used storage.

Until that ratio falls by at least 3x to 5x in favor of batteries being cheaper than generation, extra generation is going to be the way that grids actually get built out. Batteries and generation are both falling in cost fairly quickly, but generation still has the overall edge in learning rate. Cost decreases won't bottom out for at least a decade, because there's been no slow down yet, so I wouldn't expect this ratio to change for a minimum of 20 years, which means that pretty much a full energy system interchange will have happened by the time that this price ration changes.

So there's at least a few assumptions about the current industry and it's future development that underlie my assertion that a month of storage makes no sense, but I'm confident enough that I'd place money on the bet, and there's very very few things I'd bet on.

Edit: one thing that would break my assumption is the industrial development of storage that's super cheap for once-per-year usage. Most storage now needs to be cycled about 300x per year to make economic sense. "Long duration" storage is actually better defined as "economical storage at few battery cycles per year". There's nothing like that in the research hopper, but that doesn't mean it couldn't appear tomorrow and be deployed within a decade. Something that only gets used once or twice a year has to be dirt cheap, even if you could get 10x or 20x normal electricity prices for it.

That sounds better. Still leads to some questions that I am missing the answers to:

A Lithium ion has the same charge in magnitude as an elecron. Electron is much lighter. Why and how is it that Li+ ions are able to, but electrons can't?

A same number of ions and electrons should be generating on the electrodes.

>> Generally move

When there no free electron space in atoms, instead of electrons being stuck, should still move the electrolyte as free particles just like ions.

Seems like they can't in this case. Why not?

Of course you need to know the power per unit to some degree, but when you're building warehouse-sized stationary storage arrays, land is cheap and LCOS is more important than energy density. That's a very different tradeoff calculation than if you're building a car.