Like how you can fry your electronics if they’re plugged in when the power comes back on from an outage, why can’t we “unplug” everything so to speak?
In: Planetary Science
In the case of a direct hit from a massive solar flare the length of the wires plays a huge role.
You could probably unplug and turn off home electronic devices and they would be fine.
We can and do turn off entire power grids to try and protect them.
But the power grid, phone lines and other cables of great length could still suffer catastrophic overloads causing thousands of fires simultaneously if we were hit by a strong enough solar flare emp.
Assuming we managed to put out all the fires we still would not have the parts nor manpower necessary to repair the entire electrical grid and it would be a long and frustrating road to recovery.
Could Solar Storms Destroy Civilization? Solar Flares & Coronal Mass …
YouTube · Kurzgesagt – In a Nutshell
Jun 7, 2020
[removed]
Imagine this, the transformer circuit which create electricity from AC to DC, has 2 coils.
The first coil connect to the wall which alternates current, the 2nd coil produce DC current which connect to your digital devices.
When the first coil is producing +ve and -ve, it cuts the electromagnetic field and induce current to the 2nd coil giving it a certain flat voltage(assuming there is a bridge rectifier to correct all the sawtooth waveform and transform to a dc voltage).
Now, emf hits, it induce a very large current to the 2nd coils and fry your transformer in which potentially kill the circuit breaker. You can’t power up your device anymore.
Anything that has coil inside will have this effect.
This is very dangerous to sensitive digital equipment as their operation voltage and current are usually less than 3.3v.
It’s basically a lightning strike in EMF Form.
So what kills it? If current is high, so is voltage. alternating current may kill human but dc will burn things with high amperage.
So how to prevent this? Have a shield, what shield? Watch a movie and you know, faraday shielding.
EMP doesn’t come from the wires, it comes from the air and you can’t unplug something from the air. The only way to “unplug” is to have equipment in bunkers
Anything conductive can potentially have moving charges during the event.
If it were strong enough, everything from a metal roof to the circuits in your cellphone would have current “generated” in it.
You can. Turning off the power grid will protect it completely.
Solar flares are not EMP. When a solar flare hits, it generates tiny amounts of DC current in very long power lines. The problem is that the power grid only works on AC current. If any DC at all gets into it, equipment starts malfunctioning and losing efficiency. The malfunctioning equipment then starts heating up because it can’t handle the strain of the AC.
In other words, the energy in the power grid is what causes the damage, not the energy in the solar flare. It is just that the solar flare energy allows the normal power flow to cause the damage. If there is no normal power flowing, there is no damage.
The problem is that shutting down a whole power grid is extremely inconvenient, especially if you have to do it for days. Forecasting of solar flare impact is not very precise and it is not really possible to predict what effect one would have on a power grid in order to shut down selected parts.
Many power companies have installed real time DC monitoring equipment in their power lines. This allows them to monitor early impacts of the solar flare before damage occurs and then shut down selected parts as soon as they start to malfunction but before damage starts.
Even this can be inconvenient. For example, Canada has real time monitoring. The problem is that they get hit so hard by solar flares so often, that repeated automatic shutdowns of parts of the grid became a problem. They ended up installing DC blocker equipment on critical lines which blocks the effect of th solar flares, making those power lines immune to the effect.
If right now someone said: Solar flare, unplug everything!, what could you do? What could the cashier at the supermarket do? What could a chirug do?
Early warning, turning off everything that can be turned off is a good ting, but too many things aren’t built with unplugging in mind, especially not remote unplugging while you’re at work.
Let’s start with how radio works. Radio is electromagnetic waves that travel through the air. We received this waves using an antenna. When the waves hit the antenna they create a flow of electrons – and the device we call a radio figures out how to turn this into sound.
An EMP is a big loud radio. And antennas are just pieces of metal. So, in the solar flare (or nuclear explosion) scenario, every single piece of metal turns into an antenna and starts having electricity flowing through it. If it’s attached to something important and generates more electricity than that thing can handle… Bzzzzt.
So I actually took a class on this. Having devices unplugged is going to protect them the most. Anything connected to a mains that doesn’t have grid- level interrupts is going to fry.
It depends on the EMP, the object, and how it’s turned off.
The things that are going to be messed up the most by an EMP are unshielded magnetic storage and semiconductors. Unshielded meaning that there’s nothing in place to mitigate or redirect the pulse, such as conductive outer casing that is insulated from the main body (a Faraday cage). Semiconductors are used on every type of modern electronics and are prone to experience significant chemical changes when enough electromagnetic energy is passed through them in the wrong direction, burning out the chip. Magnetic storage can have its data corrupted and rendered unreadable by a strong enough EMP.
Latest Answers