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Solar power has begun to transform the world’s energy system

newyorker.com

481–490 of 607 posts

Re: Solar power has begun to transform the world’s energy system

#481

Earlier quoted context omitted.

One of the good things about solar is the lack of a mismatch between solar production curve and human needs. People use more energy during the day. People, globally, use more energy in the summer. This might not be intuitive if you live nearer the poles, but that's not representative of where the global population live. And in some of those places, like California people obsesses about the "peak" that is left after y…

this is often repeated, but is not entirely true. Peak electrical demand does not coincide with solar generation. Generally, peak demand is either early in the morning or the late afternoon, when solar production tapers. In order to make up the difference, you'd need a couple thousand megawatt-hours of battery capacity for most regions. You'd also need this to happen twice a day - either side of typical working hours…

Your link shows that yesterday had the highest peak demand of the month and it was between 1-2pm.

Spot checking July 2019 the oldest year it had, it's peak day also had the peak at the same time.

Do we have different definitions of "late afternoon"?

I also don't understand the link's differentiation between "demand" and "usage", but "demand" is higher and nearer noon it seems.

It's also not clear if home solar is accounted for and is a factor. You'll see a "demand dip" when behind the meter solar is generating if you're only seeing the grid side of things. Some grids estimate and include it or call it out separately.

Re: Solar power has begun to transform the world’s energy system

#482

Earlier quoted context omitted.

> for the same reasons the US still doesn't have any high-speed trains 60 years after the Shinkansen entered service and still doesn't have a moon base 56 years after Neil Armstrong. So.. lack of demand and ROI?

Energy independence and HSR are indeed poor metaphors for each other. In the U.S. one can travel coast-to-coast faster and cheaper in a car than they can by rail. Then, of course, there is air travel. That is to say, there are alternatives. A country completely dependent on foreign solar panels could develop non-solar alternatives. Or they could just surrender. So of course they also have alternatives. But this is ex…

> Energy independence and HSR are indeed poor metaphors for each other.

It's not a metaphor. You're reasoning very sloppily. The absence of high-speed rail in the US is caused by a societal breakdown in technological and economic development. That breakdown also causes other effects. One of those effects is that over the last 20 years the US not only failed to develop a native industry of solar panel manufacturers; it lost the world-leading native industry of solar panel manufacturers that it already had. There's no strong reason to believe that a blockade would reverse that breakdown rather than accelerating it.

> In the U.S. one can travel coast-to-coast faster and cheaper in a car than they can by rail.

Yes. That's because the US doesn't have high-speed rail, even 60 years after the Shinkansen went into service. If the US did have high-speed rail, one would be able to travel coast-to-coast faster and cheaper by rail than they could in a car. And the difference is not small.

The fastest trains on the Beijing–Shanghai high-speed rail line average 290km/h, about 3–4 times faster than a car in the US and 50% faster than even the fastest Autobahn car speeds. The peak speed is 350km/h, but as in a car, some time is wasted speeding up and slowing down at stops at the beginning and end of the trip, and along the way.

The higher speeds also lower costs; https://www.trip.com/trains/china/route/beijingnan-to-shangh... tells me that the 1300-km trip currently costs US$22 for one person, which works out to about 1.7¢ per km. In the US, driving a car typically costs 70¢ per mile https://www.irs.gov/tax-professionals/standard-mileage-rates which is 43¢/km. So driving a car the same distance would not only take 3–4 times longer, it would cost 25 times as much.

https://www.youtube.com/watch?v=uBUYDvu9XgU&t=15m25s reports that a year ago they paid US$92, which would be 7¢/km, so either trip.com is lying, they were taking a higher class of service, or the price has dropped precipitously. It looks to me like coach-class airline seating, but https://en.wikipedia.org/wiki/Beijing%E2%80%93Shanghai_high-... tells me that when the service launched there were three classes of service.

Maybe in China cars are cheaper, in which case driving would only cost 10 times as much, I don't know. But it clearly isn't going to be as cheap as taking the high-speed train.

A consequence of the US's deficits in transportation is that a large fraction of the mental energy of its professional and intellectual classes is devoted to operating cars in traffic rather than to developing vaccines, improving Wikipedia, creating video games, or even selling ads.

60 years is a long time in terms of technological development. 60 years after the Wright Brothers achieve controlled powered flight in 01903 was 01963, when both the US and USSR had orbited cosmonauts, and the Apollo Program was well underway. 60 years after the first stored-program computer was delivered in 01949 (either the EDSAC or the secret Manchester Baby) was 02009, when Intel and AMD were shipping billion-transistor six-core processors. A wealthy country not being able to deploy the already existing technology in that time frame shows that it's experiencing not slow technological and economic development but slow collapse.

Re: Solar power has begun to transform the world’s energy system

#483
post #193
post #184

Earlier quoted context omitted.

Plausible alternatives to cables include ships full of synthetic diesel, ships full of iron, ships full of aluminum, or ships full of magnesium. Inside China HVDC cables are indeed carrying solar power across the continent, but the Netherlands have not managed to erect any yet. Cables provide efficient JIT power delivery, but they're vulnerable to precision-guided missiles, which Ukrainians are 3-D printing in their…

Ships carrying energy are a pretty easy explosive target as well. Local ressilence is needed in any case and mass produced batteries can provide that safety.

We have quite a bit of experience transporting hydrocarbons . . . .

Re: Solar power has begun to transform the world’s energy system

#484
post #256

Earlier quoted context omitted.

Any country relying on international cables for electricity would need to build and maintain full local backup power capacity. The combined cost of cables + backup may be more than storage cost. (Of course there are many factors which affect all these costs)

You might say "any country relying on international pipelines for gas would need to build and maintain full local backup capacity", except they didn't. Hence the Russia/Ukraine war causing all sorts of problems.

"Full capacity" backup looks different when you have sufficient batteries on the grid. Building enough backup generation to hit peak capacity would entail a lot more gas plants than building enough to hit average capacity and using batteries to supply the peaks.

Re: Solar power has begun to transform the world’s energy system

#485
post #438

Earlier quoted context omitted.

But still not explosive at scale. It’s a surface area issue, a small strip of magnesium explodes when dropped in water but a 100t cargo of magnesium sinking in a harbor would be a huge fire.

> a small strip of magnesium explodes when dropped in water No it doesn't. Magnesium metal burns because the boiling point of magnesium is just 1091 C, so extremely reactive vapor is readily produced. But it would be very hard to heat it that high in water unless it was ignited first. It will then continue to burn under water.

Maybe I should have clarified burning, as in “Why does burning magnesium explode when sprinkled with water?”

https://physics.stackexchange.com/questions/33167/why-does-b...

Re: Solar power has begun to transform the world’s energy system

#486

It’s crazy that most emergency plans ignore geomagnetic threats—did you know a Carrington‑level flare today could knock out transformers worth hundreds of billions? What low‑cost steps could cities take now?

This seems to be more doomerism than reality. What you are saying is that the induced current will be strong enough to cause damage even after all breakers trip. Having to black start a bunch of grids world wide? Yes. Widespread damage? No.

Also, having a bunch of batteries on the grid would make a black start much easier.

Re: Solar power has begun to transform the world’s energy system

#487
post #289

Earlier quoted context omitted.

As long as we all realize you can’t 3D print precision-guided missiles without, well, the guidance bit.

The guidance bit should be quite cheap now though, compared to decades ago. Some combination of MEMS backed up with GPS.

And software. The Ukrainian drones largely run on the open-source Ardupilot.

GPS is fairly easy to jam, and despite the purported end of Selective Availability, unencrypted GPS can be turned off entirely without affecting US military GPS. Cruise missiles have been using terrain models for decades now, since well before GPS (a major reason high-resolution DTED used to be classified) which just requires a computationally cheap particle filter and appropriate sensors. We can expect belligerents in upcoming conflicts to maintain strategic stockpiles of the relevant electronics, which are more compact than even cocaine or fentanyl and therefore difficult to blockade.

Re: Solar power has begun to transform the world’s energy system

#488

Earlier quoted context omitted.

Tidal power doesn't come from the sun either. It slows the earth's rotation by a tiny amount.

Is the origin of that rotation not also the gravitational wells created by the Sun?

Good pedantry, but then we can argue that the origin of fossil fuels is geothermal (if we ascribe the origin of life to hydrothermal vents).

Re: Solar power has begun to transform the world’s energy system

#489

I just can't get that exuberant when I also read things like this [1]. [1] - https://thehonestsorcerer.substack.com/p/the-tale-of-two-ene...

That article's whole premises seems to hinge on the quote: "Energy from non-fossil fuel combustible electricity generation is accounted for on their input heat requirements and non-combustible renewables on the energy content of their gross electrical output."

But that line means the exact opposite of what the author claims it means. He claims that renewables are being overinflated, but the reverse is true. Coal and gas get evaluated based on their heat content, not their useful work output. Wind and solar get evaluated on their electrical output.

Re: Solar power has begun to transform the world’s energy system

#490

Earlier quoted context omitted.

The article notes several examples of reduced use of fossil fuels: > California is so far using forty per cent less natural gas to generate electricity than it did in 2023 > total carbon emissions in China had actually decreased > kept the country’s coal use flat and also cut the amount of natural gas used during the same period in 2024 by a quarter

Meanwhile Germany shut down its nuclear plants while keeping coal and natural gas around to supplement renewables. One of the biggest unforced errors I've heard of recently.

Natural gas and coal are better at throttling up and down than nuclear plants are.

So if they need to run 10% of the time, then you've still reduced your carbon output by 90%. The goal is 100%, but the remaining fossil fuel plants are not the biggest issue.

A nuclear plant would also be carbon-free, but Germany had other reasons not to want it. So it was a reasonable decision to keep the fossil fuel plants around, and shut more and more of them down over time.

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