- This has nothing to do with "EMP". That's a big but brief RF pulse with a rise time around 1ns. This is induced DC in long wires over a period of hours.
- The basic effect is that a current is induced in the earth's crust, resulting in a DC voltage between grounds at widely separated points. This is mostly a problem for long AC high-tension power lines using wye-connected transformers at each end which run in the same direction as mountains of igneous rock. The DC component can partially saturate the transformer, using up some of its capacity. If undetected, transformers can overheat, and worst case, burn out. This occurred on March 13, 1989 on some lines in the eastern US.
- PJM, which runs the northeastern US power grid, is now prepared for this. See PJM's training manual for this[1], starting at page 22. They get 1 to 6 days warning from the NOAA's Space Weather Prediction Center. They have monitoring for unwanted DC flows at multiple points in the power grid. When trouble appears, certain power lines have to have their current reduced.
- A few times a year, more at the top of the sunspot cycle, there are warnings of a potential problem. PJM last issued a warning on August 26, 2018. It didn't progress to an "alert", or actual action. There are people in a control room in Valley Forge, PA, and another backup location, watching this. They can reroute power around the trouble spots, call for extra generation output, and dump some loads if necessary. Load dumping starts with bulk buyers of "interruptible power" - aluminum smelters, Bitcoin mines, etc., which are willing to be the first turned off in exchange for a discount.
- It's not a problem for anything shorter than hundreds of miles. It's not a problem for high-voltage DC power lines, like the Pacific Intertie and the really long ones from western to eastern China. It has zero effect on fiber optics or small devices.
- When you encounter clueless reporters writing about the power grid, aim them at "PJM 101", which is a set of introductory training materials on how the power grid works, written for people who run it.
[1] https://pjm.com/-/media/training/nerc-certifications/gen-exa...
PJM has online training courses. Taking "PJM 101" is worth it to get a sense of how the market system and the actual operation interact. A few hours and you know more about the power grid than 99% of the population, but less than any PJM employee or energy trader.
One of my interests is how market-based systems fail. They're feedback systems with delays. Some of the delays are short; others are measured in years. A point I make regularly is that such systems have no guarantee of stability. In short-term energy markets, the consequences of this are immediate, because there is not much inventory in electricity.
(of a person or their manner) unwilling or unable to believe something.
Think you meant incredible/unbelievable etc.
Did not expect to see them in a conversation about electricity infrastructure and aluminium smelters. Interesting times we live in.
[0] http://www.lloyds.com/~/media/lloyds/reports/emerging%20risk...
I followed the link on this article to the article on a more recent solar storm (https://en.wikipedia.org/wiki/Solar_storm_of_2012) where I found a report from Lloyd's which mentions that there are workarounds (like "neutral-current-blocking capacitors"), so it might be possible to make even large power transmission systems resistant against solar storms.
Last I checked it was something like $100/watt and was 10-25% efficient (plug-plug). The system I worked on used “standard” fiber as the hollow core stuff still had too many drawbacks.
> A general problem of hollow-core fibers is that their propagation losses are substantially higher than for solid-core fibers – in particular when single-mode guidance is required.
What a fascinating read.
It really makes you happy that this type of solar/planetary stuff affecting the earth only happens on such a long timescale where it doesn't commonly affect our day-to-day lives as much as earthborn issues such as severe storms or other extreme meteorological events. But it's also a shame in some ways:
> Myself and two mates looking out of the tent saw a great reflection in the southern heavens at about 7 o'clock p.m., and in about half an hour, a scene of almost unspeakable beauty presented itself, lights of every imaginable color were issuing from the southern heavens, one color fading away only to give place to another if possible more beautiful than the last, the streams mounting to the zenith
We got lucky in 2012. [1]
[1] https://science.nasa.gov/science-news/science-at-nasa/2014/2...
Why would NASA not share this with the public?
