It's really the alkalinity (e.g. the Mg++ or Ca++), which silicate rocks often have (but technically not limited to silicates).
As an aside, we need to dissolve roughly one large mountain into the mix layer (top ~50m) of the ocean to have it fully take up atmospheric CO2. Without dissolving, the reaction is very slow (co2 in atmosphere => slightly lower pH rain => reaction with mostly passivated rock + erosion).
True. But that’s never the framing you hear from astronomers. It’s how the satellites are “ruining” the pictures, like this whole thread.
The SNR degradation isn’t even very much. Noise goes down by 1/sqrt(N) samples. In a stack like this might have 5-40 images depending on how they did it. Typically a satellite will only show up on one of those images for a given pixel. So by excluding that image from the stack that pixel’s noise would go up by a ratio of sqrt(N/(N-1)) which for 5-40 images is between 12% more noise and 1% more noise. Only the pixels with satellite tracks.
True there’s more noise if you remove the satellites. But it’s probably only a few percent noisier, and only in the places where the satellite flew. Add a few more images to the stack and accept that the world is changing.
I am not arguing either way, but I think you missed the point.
When you give O(20000) people you have a 1-0.9999^20000 (high) probability that that will leak anyway (either 1/20000 people not following the rules, or just the accident/attack surface area).
The speed of charging is irrelevant, because the energy consumption is the same. The power requirements for a charging station is determined by the number of cars charged in a day, not by how fast they are charged.
The fast chargers that achieve charging in a few minutes, and which are indeed able to provide up to 1 MW of charging power, have their own internal batteries, so they take from the electrical grid a power averaged over a long time, not the peak power that they provide to the charged vehicle.
but in an hour, these stations have to charge 7 cars now whereas in the past, they only had to charge 1. So power requirements for these stations went up by 7x. Sure, they can fill up at night but they would need a lot more batteries on standby.
> in an hour, these stations have to charge 7 cars now whereas in the past, they only had to charge 1
Why? Where do those extra cars come from? In reality the change you're going to see is from spending 30 minutes to charge 1 car followed by 30 minutes of sitting idle to spending 5 minutes to charge 1 car followed by 55 minutes of sitting idle.
Or, alternatively, go from 6 stations each spending 30 minutes / car to charge 12 cars per hour to 1 station spending 5 minutes / car to charge 12 cars per hour.
The electricity demand only depends on the number of miles driven. Same with ICE cars: the speed through which fuel comes out of the gas station's nozzle doesn't impact how much fuel you consume during your commute, or how often the gas station needs to be resupplied.
The whole fast charge thing is mostly marketing to convert people from "gas car mindset" into getting an EV.
The reality of the situation is that most people who buy an EV will use fast charging only a few times a year. The majority will be charging overnight to recuperate their daily use, which amounts to drawing <1% of a MW. The grid, in it's current form, is totally capable of this.
What would be a strain though is large ultra fast charging stations along major travel corridors. But I'd still wager that those will be overkill for most.
Charging was what stopped me from getting an EV when I was a renter. In a world where I can recharge in 7 to 10 minutes, it becomes a lot more feasible for a renter to get an EV without at home charging capabilities. A renter can just pull up to a recharging station. Wait 7 to 10 minutes or (maybe 5 if they don't mind a half charge) and be off.
> renter to get an EV without at home charging capabilities.
Assuming that your car is parked for 18 hours of the day or more (and if it is not, you're a courier, taxi driver or similar) the question is not "do I own or rent the place where I live?" it is "How do I get electricity to where the car is normally parked?"
If you solve that with a L2 charger - at night or during the day, you're good. Then recharge time becomes irrelevant as you don't stand there waiting for it, and it happens as part of daily routine. You don't have to regularly pay attention to "When do I have to go get fuel?", it's just done daily.
Electricity is found nearly everywhere, you do not have to treat it as something found only at a special fuelling station. EVS are unlike gas cars in that respect.
For this sort of fast charging you need the charging station itself to have a large pool of batteries to buffer the energy from the grid and to push it at very high power to cars. Probably still requires a good size connection to the grid.
I think this is unavoidable for any sort of decent charging station from now on, anyway but does require significant investment in infrastructure.
Obviously, the engineers at BYD, CATL etc. are not stupid, so these fast chargers, which have been in production for several months and which are already installed in an increasing number of places, do include batteries, so they need only an averaged power from the electrical grid, not the up to 1 MW power that is provided to the charged vehicle.
BYD was the first company demonstrating such batteries and chargers, but CATL followed after a short time. While the times reported by CATL are slightly longer than for BYD at room temperature, these CATL batteries have faster charging at low temperatures.
It is nice to see healthy competition between the major Chinese battery producers. Unfortunately, there is much less competition for them from other countries.
The electrical grid infrastructure that is needed does not depend on the charging speed, but it is determined by the number of cars that are charged per day at a given location (and their average battery capacity).
For pulsed power, with an optimistic beta of 1, the magnetic field energy is going to be comparable to the heat energy. The house load here seems tied to a static superconducting coil, not a pulsed field.
And can in many cases be much higher than the heat energy (e.g. theta pinch).
This would not pass peer review for a journal as written.
Maybe the conclusion is correct, or maybe not, but as written the methodology is under specified, statistics are not supported, and there too many confounders not addressed. One should not take anything from this without a better write up. Just misunderstanding what n= means is a huge flag.
Since the author is here, I have to ask: Why a blog post and not an actual paper? Why spray this onto the internet without validating the work? Or, conversely, why not caveat the work as exploratory data science?
Fun info: The NASA orbital codes include things like photon pressure... from sunlight reflected off of other planets in the solar system. At some point, I think they are just showing off :)
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