How rooftop solar can prevent the apocalypse

Adam Taggart
By Adam Taggart on Mon, Mar 30, 2015 - 2:33pm

Here's an article explaining the dangers of a takedown of the US electrical grid and how a distributed national network of rooftop solar installations would offer one of the best defenses against such a dire scenario. The article also details the major obstacles to such a sound idea: politics, and power plays by major utilities:

How rooftop solar can prevent the apocalypse

There is one doomsday scenario that is frighteningly based in actual possibility and for which the U.S. is remarkably and negligently unprotected: the loss of the electric grid.

Here’s how an energy consultant named Chip Register describes a recent conversation he had with former CIA Director James Woolsey:

In a previous article, I had a conversation with former-CIA chief Jim Woolsey to discuss one of America’s greatest national security vulnerabilities, its power grid. The issues that Woolsey has been concerned with for over a decade has been the ease in which a terrorist group or other actor (think North Korea for example) could attack the grid and plunge the country into darkness for months, if not years. And if that seems far-fetched, just recall how a tree limb fell in Ohio in 2003 and blacked out the entire Northeast and part of Canada for several days.

Woolsey describes several scenarios of how the grid could be taken down for an extended period of time by anyone with the means and the will to do the nation, and the world, great harm. His focus was on EMP, or electromagnetic pulse. That’s part of the radiation blast emitting from a nuclear detonation, and it has the effect of rendering all forms of electrical devices useless. Radio, televisions, telephones, and, yes, power stations would all essentially fry from the inside out if exposed to such an event. Permanently.

Still seemed far-fetched? It really isn’t. A very small and unsophisticated nuclear device (which is or could be in the possession of many American foes) could be attached to a weather balloon launched from a boat in the Gulf of Mexico or off of California and floated to the county’s mid-continent where its detonation would have the greatest effect. America would literally go dark. No phones. No money. No heat. No running water. No medicine. No police. Just darkness.

Congressional studies quoted by Woolsey estimate that two-thirds of the population would die of starvation, disease, exposure or violence related to social breakdown in the first twelve months alone.

And to make matters worse, we would never even know what hit us, because we would have no means to investigate, to say nothing of respond. Just darkness.

The idea of an EMP destroying the electric grid isn’t new–the possibility has been known for decades. A well-designed cyber attack could result in the same scenario. But Woolsey, and most people who have tried to raise awareness of the issue, tend to leave out of their descriptions the most important and devastating consequence of grid destruction: the undeniable reality that every nuclear reactor hooked up to the grid would melt down. And the meltdowns of nearly 100 nuclear reactors–and a few fuel pools still at closed reactors–would release enough radiation to make just about the entire nation permanently uninhabitable.

It turns out that the most effective way to protect the grid is also how we get to a clean energy system. The two go hand in hand. As Wellinghoff argues effectively, an electric grid based on distributed generation is an electric grid that is essentially invulnerable to attack, whether through EMP, cyberwar or some other form of assault.

Register’s interview with Wellinghoff gets a little wonky, but is well worth reading and bringing attention to. Who knew that rooftop solar power, for example, is not only good for the environment and the pocketbook, but is essential to protecting national security?

Says Wellinghoff: “If everyone had solar panels on their respective roofs then we could adequately disperse power generation in such a way that it makes nodes [a small number of centralized high voltage substations used in the current grid architecture] practically irrelevant. It is easy to hack into a node and cause it to malfunction but it is basically impossible to hack 10 million solar power systems.”

Click here to read the full article

29 Comments

kd6iwd@gmail.com's picture
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emp takedown of electric grid

I would like to point out that a solar panel is really a large transistor junction and as such would  be  destroyed by a emp event caused by a nuclear  bomb. Stored panels can be protected from an emp event by being first wrapped in paper, and then wrapped in three layers of aluminum foil. This protects the panel from the high voltage emp event. This would work for radios and spare transistors as well.

 

Best Regards

 

Jim

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And computer hard drives too?

And computer hard drives too? The transistors in those are so tiny and I imagine more vulnerable.

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Jim is right...

I was thinking the same thing.. and aside from the panels, many of the other components within the solar energy system could be fried as well in an EMP event.  You would probably want to have not just panels protected (via shielding or creation of some kind of home made Faraday cage) but versions of critical components as well.  Note that Faraday cages should be grounded for best effectiveness.  

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Phaedrus the younger
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devil's advocate

Assuming only a single device brings down the grid, presumably only the unprotected devices unfortunate enough to be within the EMP blast radius get fried.   The rest of the continent experiencing grid blackout would be able to use their solar systems.   So the question for me is: how likely will my region be inside the EMP blast radius?

Adam, I like your thinking and it's worth the risk in my mind. 

ps  I am thinking about how to protect my inverter/charger at the very least.   ;-)

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Thanks for bringing this point in the article up, Adam

Thanks for bringing this point in the article up, Adam

"The idea of an EMP destroying the electric grid isn’t new–the possibility has been known for decades. A well-designed cyber attack could result in the same scenario. But Woolsey, and most people who have tried to raise awareness of the issue, tend to leave out of their descriptions the most important and devastating consequence of grid destruction: the undeniable reality that every nuclear reactor hooked up to the grid would melt down. And the meltdowns of nearly 100 nuclear reactors–and a few fuel pools still at closed reactors–would release enough radiation to make just about the entire nation permanently uninhabitable.[bold & italics mine]

I never really thought about this until the Fukushima disaster.  But after that, the 40 watt light bulb went off over my head.  I looked at a map of all the nuclear power plants in the US and I reeaaaaally didn't like what I was seeing.  I'm no expert on this stuff, and so wondered if I was interpreting the potential situation correctly (especially because no one talks about it).  Unfortunately, the article seems to confirm those fears.  How the heck do you mitigate that risk (other than moving to who knows what country)??

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Solar and wind

With reference to Jim's comment I think the point is that an EMP event would certainly fry everything in the vicinity but the overall grid could still function...a faraday cage around a solar panel would block the sun . You could not protect yourself. If you happen to live near the EMP event you end up taking one for the team

We still need power at night so wind should be included in this article.

Mots's picture
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emp takedown of electric grid

Re: "a solar panel is really a large transistor junction and as such would  be  destroyed by a emp event caused by a nuclear  bomb"

No, not so.  At best a solar panel is a low impedance diode, which already experiences EMP from the environment and is protected as such by devices such as a metal oxide varistor, lightening arrestors and other static pulse protectors.  A trillion volt EMP pulse over a 10000 meters works out to a very small voltage difference at the panel cross section.  Furthermore, punching a small hole in the big panel surface might not even be noticeable (even if an EMP could do that) since the panel output comes from accumulated intact surface area and current flow inherently bypasses such defect for several reasons.   Anyway, solar panels already are protected, to the extent they need it.  I would be much more worried about the shock wave.

 

I started a small company to develop low cost high efficiency neighborhood grids (LocalGrid, LLC) based on our own technology. We make/sell small upload and download boxes to connect panels to a nodal grid you make yourself from wire bought at Home Depot.  Anyone interested seriously in working on this please contact me. We are working in Virginia and in an Asian country on development.

There are many reasons to develop a local grid, even if only between buildings on a farm/estate or between a few friends who live near each other.  We are swimming in an ocean of energy and can have a luxurious lifestyle regardless of what everyone else is doing, if we use appliances with patient scheduling.  I can make coffee and fry potatoes even when it is raining out, because of my more efficient circuitry coupled with cheap abundant solar panels and NO batteries.

Mots

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Emp and Nuclear Power Plants

Meltdowns may not be  an EMP side effect:

yahoo best answer wrote:
 I work at a nuke doing electronics. First, there haven't been any new nukes in the US for almost 20 years. This means that electronic technology in this field is minimal. Computers as we know them are a fairly recent technology. Most all safety relaying, (safety meaning required for the safe auto-shutdown of the plant), is done with electro-mechanical relays which are numb to EMP. The safety systems are designed to be "Fail Safe", which means that if a component fails, it fails to a condition that will allow or promote safe shutdown. So....if the power shuts off for some strange reason, the component "fails", etc. Also, if a system has been upgraded due to the lack of parts availability for the old stuff, it has to meet stringent qualifications in order to be acceptable. Nuclear power is one of the safest industries in the world. 
 
 
It's always a good idea to verify things you read on the net.
 
The answer above reminds me of SCUBA equipment, which is designed to fail open.  If it stops working properly, it sends a continuous flow of air to your mouthpiece, rapidly emptying your air supply, but giving you time to reach the surface.  
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what about Fukushima

From what I understand, a recently shut down nuke needs grid power or locally generated backup power (diesel generators usually) to maintain a flow of cooling water.  Diesel for the backup generators can run out in a few days or a week.  At that point cooling water stops flowing and a Fukushima-like meltdown can occur.  Am I wrong?

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Grounded Independent Solar Panel System--little risk from EMP

I took the above concern to my electrical engineer friend, Gerry, who offered his thoughts on the subject.  He works for the national radio-astronomy telescope project and build a solar powered free standing electrical shop for use in a remote location.

1.  This discussion is for PV systems that are NOT grid tied--i.e. free-standing independent systems.

2.  He agreed with Mots assessment that a PV panel was a "low impedance (resistance) diode" that would generate little current over the short distances of a single panel during an EMP.  He felt that a mounted PV system would do well in an EMP.

3.  There IS information of damage and protection from LIGHTNING--an electrical event that behaves very similarly to an EMP.

http://www.wholesalesolar.com/solar-information/grounding-lightning-protection

4.  He recommended grounding a home PV system to protect the PV panels itself and all of the attached electronics from voltage surges of EMP or lightning strikes.  This involves sinking a 4 foot long copper rod deep into the earth and connecting it to the "negative side" of the battery.

From the above article:

Lightning and related static discharge is the number one cause of sudden, unexpected failures in PV systems. Lightning does not have to strike directly to cause damage to sensitive electronic equipment, such as inverters, controls, radios and entertainment equipment. It can be miles away and invisible, and still induce high voltage surges in wiring, especially in long lines.

My own customers have reported damage to inverters, charge controllers, DC refrigerators, fluorescent light ballasts, TVs, pumps, and (rarely) photovoltaic panels... ALL reports were from owner-installed systems that were NOT GROUNDED.

GROUNDING means connecting part of your system structure and/or wiring electrically to the earth. During lightning storms, the clouds build up a static electric charge. This causes accumulation of the opposite charge in objects on the ground. Objects that are INSULATED from the earth tend to accumulate the charge more strongly than the surrounding earth. If the potential difference (voltage) between sky and the object is great enough, lightning will jump the gap.

Grounding your system does four things: (1) It drains off accumulated charges so that lightning is NOT HIGHLY ATTRACTED to your system. (2) If lightning does strike, or if a high charge does build up, your ground connection provides a safe path for discharge directly to the earth rather than through your wiring. 

LesPhelps's picture
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Shutting down a nuclear plant
Quercus bicolor wrote:

From what I understand, a recently shut down nuke needs grid power or locally generated backup power (diesel generators usually) to maintain a flow of cooling water.  Diesel for the backup generators can run out in a few days or a week.  At that point cooling water stops flowing and a Fukushima-like meltdown can occur.  Am I wrong?

There is a lot of variability in discussion of shutting down nuclear reactors.  Supposedly, it takes seconds to insert the control rods to stop the reaction.  However, a reduced level of cooling is required for a period of time to get rid of residual heat.  Here is another yahoo best answer:

yahoo best answer wrote:

To stop the Nuclear reaction you insert control rods which absorb neutrons, preventing further chain reactions.  Even after you stopped the reaction, residual heat is still produced by the decay of the radioactive fuel, it takes about 10 days to fully cool down. 

 
I can't imagine a nuclear plant being commissioned in the United States without a backup electric supply adequate to handle a safe shutdown.  That would seem to me to be a basic minimum precaution.
 
Decommissioning a nuclear plant is another matter.  I suspect that grid power would be required to completely clean up and permanently close down a nuclear plant.
 
I believe melt down is caused by incorrect shut down, not incorrect decommissioning.
 
The US is vulnerable in a wide variety of ways.  Here is one that concerns me more than EMP.  An adversary  could cause Yellowstone to errupt with a single nuke.
 
 
There are assessments available concerning the possible impact of a Yellowstone supervolcano eruption.  It is not pretty.
 
Mots's picture
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safe nuclear power

Re: "I can't imagine a nuclear plant being commissioned in the United States without a backup electric supply adequate to handle a safe shutdown.  That would seem to me to be a basic minimum precaution."
Your point is well taken and, maybe this works fairly well most of the time in continental US that experiences few earthquakes.

But a 60 foot wave of water overpowered the electrical backup diesel generators at a Japanese nuclear power plant and caused multiple meltdowns.  That is not conjecture.  Really happened. Believe it.

We can expect further meltdowns and partial meltdowns via stupidity (as demonstrated in the Ukraine some years ago when a reactor was being used for an experiment).  Really happened, no longer conjecture or a bad dream but reality.  Fact, not fiction or "low probability."  

We could expect similar from intended sabotage.

People are willing to crash air planes via carefully planned deliberate actions, as seen recently at a German airline.  This is reality, actually happens, not chit chat internet conjecture.  Believe it.  Factor it into your thinking of disasters.  Why cant a dedicated crazy nuclear power plant operator do the same? 

and so on and so on.

The US decided to follow uranium fission instead of the more inherently safe thorium because of the desire for more and more uranium bombs.  This is a nuclear-festival country, with large areas of federal land contaminated by the federal nuclear industry party and the legacy of over 50,000 bombs, and many satisfied rich investors.  The existing bombs and associated waste and stockpiled energy industry waste are completely ignored and probably much more dangerous than the topic of this "nuclear energy industry safety" discussion. This is hopeless and not addressed.  

This internet chit chat is superficial and not satisfying.  It is not correct to chit chat a bit about backup systems and feel good about it.  If there is no time to really understand the entire situation, then the most productive conversation might be to determine the best places to run away to.....................

Mots

 

 

=LesPhelps]

Quercus bicolor wrote:

From what I understand, a recently shut down nuke needs grid power or locally generated backup power (diesel generators usually) to maintain a flow of cooling water.  Diesel for the backup generators can run out in a few days or a week.  At that point cooling water stops flowing and a Fukushima-like meltdown can occur.  Am I wrong?

There is a lot of variability in discussion of shutting down nuclear reactors.  Supposedly, it takes seconds to insert the control rods to stop the reaction.  However, a reduced level of cooling is required for a period of time to get rid of residual heat.  Here is another yahoo best answer:

yahoo best answer wrote:

To stop the Nuclear reaction you insert control rods which absorb neutrons, preventing further chain reactions.  Even after you stopped the reaction, residual heat is still produced by the decay of the radioactive fuel, it takes about 10 days to fully cool down. 

 
I can't imagine a nuclear plant being commissioned in the United States without a backup electric supply adequate to handle a safe shutdown.  That would seem to me to be a basic minimum precaution.
 
Decommissioning a nuclear plant is another matter.  I suspect that grid power would be required to completely clean up and permanently close down a nuclear plant.
 
I believe melt down is caused by incorrect shut down, not incorrect decommissioning.
 
The US is vulnerable in a wide variety of ways.  Here is one that concerns me more than EMP.  An adversary  could cause Yellowstone to errupt with a single nuke.
 
 
There are assessments available concerning the possible impact of a Yellowstone supervolcano eruption.  It is not pretty.
 
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Mots wrote:The US decided to
Mots wrote:

The US decided to follow uranium fission instead of the more inherently safe thorium because of the desire for more and more uranium bombs.  This is a nuclear-festival country, with large areas of federal land contaminated by the federal nuclear industry party and the legacy of over 50,000 bombs, and many satisfied rich investors.  The existing bombs and associated waste and stockpiled energy industry waste are completely ignored and probably much more dangerous than the topic of this "nuclear energy industry safety" discussion. This is hopeless and not addressed.  

This internet chit chat is superficial and not satisfying.  It is not correct to chit chat a bit about backup systems and feel good about it.  If there is no time to really understand the entire situation, then the most productive conversation might be to determine the best places to run away to.....................

Mots

I can't argue with the first sentance above. It is a path I would have preferred as well.

The second paragraph parses down to "anyone who doesn't think exactly like I do, should be silent." Good luck with that.

kd6iwd@gmail.com's picture
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emp

I still am concerned about damage to a solar panel during an emp event. You indicated that due to the size of the panel the voltage per meter would be insufficient to damage it. As I recall, i read somewhere that car computers would likely be damaged in a emp event and so our cars would be disabled. Seems to me a car with all of that metal surrounding the electronics is much better shielded than the solar panel.

Best Regards

Jim

 

 

kd6iwd@gmail.com's picture
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emp

I still am concerned about damage to a solar panel during an emp event. You indicated that due to the size of the panel the voltage per meter would be insufficient to damage it. As I recall, i read somewhere that car computers would likely be damaged in a emp event and so our cars would be disabled. Seems to me a car with all of that metal surrounding the electronics is much better shielded than the solar panel.

Best Regards

Jim

 

 

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good luck with that

The issue is that a big piece of metal feed into a sensitive device positioned to receive that energy and respond via a sensitive junction (radio input). A car is not connected to ground and can act as an antenna.  A sensitive receiver by definition picks up energy from the atmosphere very well via antenna orientation and by interposing the receiver BETWEEN an effective antenna and ground.  This is why radios and wifis etc are vulnerable and why amateur radios should be disconnected from ground and from antennas when a storm (either natural or EMP unnatural). Any radio or wifi receiver is designed and positioned to receive energy from the sky.  Further, any energy that goes INTO a car has nowhere to go because it is not grounded. These are reasons why they would fry. A tiny transistor junction positioned for maximum sensitivity to sky signals gets pierced easily and fails easily.  A big sheet of pn junction gets pierced somewhere and still works is the other reason.

My message was that this is not a substitute for a 20 week intensive class forum on a single topic to seriously understand something and that chit chat shallow thinking  (which most people in N America seem to substitute as "education" in this age) is misleading and only good for overall simple behavior such as how to flee something.  I dont need shallow discussion and will not comment further. .

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Since You Brought It Up

Understanding fully the secular "facts only" worldview here, I feel compelled to add to this conversation an observation about the potential for a nuclear attack (or emp attack followed by multiple meltdowns) that is detailed in biblical prophecy concerning the United States.  I will post a link to a book about the matter for those who may be interested in reading about the (dim) future of the United States.  It is harrowing reading and well researched.

http://www.amazon.com/End-America-John-Price/dp/0984077111/ref=sr_1_1?ie...

If you find such references superstitious - then please ignore my post and respect that "tolerance" is defined thusly:

tol·er·ance
ˈtäl(ə)rəns/
noun
 
  1. 1.
    the ability or willingness to tolerate something, in particular the existence of opinions or behavior that one does not necessarily agree with.
    "the tolerance of corruption"

 

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Mots wrote:The issue is that
Mots wrote:

The issue is that a big piece of metal feed into a sensitive device positioned to receive that energy and respond via a sensitive junction (radio input). A car is not connected to ground and can act as an antenna.  A sensitive receiver by definition picks up energy from the atmosphere very well via antenna orientation and by interposing the receiver BETWEEN an effective antenna and ground.  This is why radios and wifis etc are vulnerable and why amateur radios should be disconnected from ground and from antennas when a storm (either natural or EMP unnatural). Any radio or wifi receiver is designed and positioned to receive energy from the sky.  Further, any energy that goes INTO a car has nowhere to go because it is not grounded. These are reasons why they would fry. A tiny transistor junction positioned for maximum sensitivity to sky signals gets pierced easily and fails easily.  A big sheet of pn junction gets pierced somewhere and still works is the other reason.

My message was that this is not a substitute for a 20 week intensive class forum on a single topic to seriously understand something and that chit chat shallow thinking  (which most people in N America seem to substitute as "education" in this age) is misleading and only good for overall simple behavior such as how to flee something.  I dont need shallow discussion and will not comment further. .

Actually, you have capacitive coupling between the bottom of the chassis and the ground, so per I = 1/C * dv/dt you can and do have current flow through the car and hence energy flow. The capacitance is weak for two reasons: First, the dielectric is air, which is a crap material for capacitors, and second, capacitance is inversely proportional to the distance between the excitation planes. HOWEVER, if dv/dt is large, and with EMP it will be, It can be significant enough to damage electronics in the vehicle. Plus you will have complex resonant structures within the geometry of the vehicle itself, which will give rise to potential gradients, which give rise to charge movement, aka current flow. Given that lightening and EMP has a spectal BW in the 30-300 MHz range, the impedance to ground would be magnitude [ 1/  [ Frequency *(permittivity of air * cross sectional area of the chassis) / (Distance of the chassis to the ground)]. An E field of several thousand volts per meter is going to cause current flow, particularly if the surface area incident to it is relatively large.  One more thing. Energy cannot "go into the car" and not leave it (Conservation of Energy and Entropy Laws). The vehicle would eventually seek equilibrium and hence a lower entropy state so the energy would either dissipate (via I^2R in the metal with the circuit closed through the capacitive coupling to the ground plane)  or be reflected. Think about it. If the energy had "nowhere to go" then the car would remain at a potential difference greater than the surroundings, and that is absurd, right? Also, most MOSFET transistors have an internal reverse biased diode structure (intrinsic, due to the doping structure) and can withstand some very very short term overstress, but not all that much and certainly not for long. This is particularly true of CMOS. 

 

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emp

In searching for accurate information about emp events and cars I found a reference which indicated that a diesel generator with no transistorized parts was shorted out by a nuclear test http://www.futurescience.com/emp/vehicles.html. Apparently emp events can easily generate 7,500 volts per meter and with more modern bombs the thinking is that voltages can reach 50,000 volts per meter. In 2000 there was a small test which used cars and an emp generator in Denver. the cars survived but the test was stopped at a point where no serious damage was done to the car at levels far less than the emp generator maximum. Some vehicles were disabled and had to be towed away.

Best Regards

Jim

 

 

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[email protected] wrote: In

In searching for accurate information about emp events and cars I found a reference which indicated that a diesel generator with no transistorized parts was shorted out by a nuclear test http://www.futurescience.com/emp/vehicles.html. Apparently emp events can easily generate 7,500 volts per meter and with more modern bombs the thinking is that voltages can reach 50,000 volts per meter. In 2000 there was a small test which used cars and an emp generator in Denver. the cars survived but the test was stopped at a point where no serious damage was done to the car at levels far less than the emp generator maximum. Some vehicles were disabled and had to be towed away.

Best Regards

Jim

Jim. Your gut feel, as I am inferring from the content of this post, is correct. Let me walk you through this as this field of physics is what I was trained in. 

First, when you hear the word "pulse", throw out the idea of DC electrical circuits, or frequencies low enough where they start to demonstrate DC-like behaviors (such as, believe it or not, common 50 Hz of 60 Hz AC). These are the basic concepts that most people know about electricity. This is an RF (radio frequency) pulse and it's physics behave FAR differently than common AC or DC for that matter. So unfortunately those concepts that most know are largely worthless and inapplicable here. 

DC and power AC (50-60 MHz) obey a pattern called Lumped Linear Time Invariant (LLTI) behavior whereas RF power obeys a paradigm of behavior called Distributive Network Theory or Transmission Line behavior (TL). 

This is a very important, but abstract as hell concept to grasp, and when most students of engineering are first exposed to it, well, it made us feel like we just got our noodles baked by EMP! LOL

Let me give you the summary of what is important without frying your brain too. It wasn't pleasant for me so if I can spare you the pain all the better. ;)

The short of it:

1. The electrical knowledge that 99% of folks know is based on obeying LLTI rules . Ground is ground, and when you hook a circuit up to ground any energy on that ground is harmlessly channeled to the zero volt reference of the circuit (earth for your home wiring, or the chassis of your car) provided that the path is low impedance (resistance) relative to the current being channeled. This is not necessarily true for high frequency, RF electricity that follow transmission line behaviors. In fact, a ground path, at the right legnth, can actually reflect energy away from the ground! Also with LLTI, the physical lengths  of the geometries of the circuit of interest do not factor into the equation because they are much much smaller than the wavelength of the electricity. (For RF, the length of a conducted path, as well as the shape of the path can dramatically change the way the circuit behaves, and this behavior is not always straightforward.  Not so for DC, and for simple AC, while this is true, the lengths needed to change the behavior are in the thousands of kilometers!)

2. All electrical signals with a frequency greater than 0 (DC) have a wavelength associated with them. Calculating that wavelength is easy parcheesy. Good figure of merit is to divide the speed of light, in meters/sec by the frequency. That is, Wavelength = (Speed of light)/(Frequency). So for 60 Hz AC, its wavelength is 300e+8/60 = 5000 km, or about 3000 miles! For EMP which has among it's many components a frequency of 300 MHz, the wavelength of that particuarly component is 1 meter. Big difference.  

3. Why is (3) important? Because when the physical dimensions of the system to which the electrical energy is flowing through are close to the wavelength, the standard, and simplified assumptions about how energy flows fall apart, and analysis becomes far more complex. If the physical system, like a car, is extremely complex geometrically then behavior can become downright unpredictable (things such as humidity, temperature, the angle at which the electromagnetic energy "hits" the car all affect the overall circuit behavior and hence energy flow). Example. A car has four rubber tires connecting it to earth ground, so it is not grounded, right? At DC and nominal AC frequencies that is certainly true. At substantial RF frequencies you can darn well bet the farm that it IS grounded! Now to complicate the situation even further. That ground may either help, or hurt your interior electronics in a way that is not readily apparent or easy to understand. Noodle baking time! LOL

The outside skin of the car, if metallic, can and does provide some protection, but it is a complex geometry so predicting that response is difficult at best and statistical in nature.  The nuanced shapes within and along the surface of the car can give rise to something called "resonances" which produce local hotspots of energy coupling. This is important because "hot spots" can be created where the coupled voltage is significantly higher at one point of the vehicle than the other, giving rise to localized current flow. That current flow, if positioned along the right path, could fry electronics. Or maybe not, depending on the type of car, type of circuitry, and many other factors. 

So there is no easy answer to a question like this, but based on common knowledge of the theories associated with this type of observation the best answer is that some cars would be affected severely, others slightly affected, and some not at all, and that risk is difficult to impossible to quantify for any given car. 

To close, I will say this. Contrary to a post here mentioning that EMP energy at some distance from the source is negligible, I can certain say with absolute confidence that it is not! Studies from the US and Soviet Union in the 60's and 70's have recorded EMP electrical fields of 50,000 volts per meter at the surface. Using a relation called the intrinsic impedance of air, we can find the associated magnetic field (for various reasons there MUST be a magnetic field associated with it). Once we have the magnetic field we can find the power density (watts per meter) incident on objects at the surface. I estimate that to be around 6.6 Megawatts (million) watts per meter (50,0000/377) which is consistent with the literature. Remember, this power is at RF frequencies, where the behavior of the energy associated with that power is not nearly as predictable as run of the mill AC power. Huge power densities plus transmisision line behavior plus complex geoemetries will spell serious trouble in a lot of situations. 

With that in mind, I would opine that given the two extremes of a.) EMP would end the world as we know it, or b.) have little overall affect at all, the truth is somewhat in-between, but leaning more heavily towards the former. 

Hope this helps. 

Morph. 

 

 

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Morpheus
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Units correction from my last

Units correction from my last post. The power density is in MW/square-meter, not MW/meter. This is a typing error as the later is physically nonsensical. 

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EMP is possible, but geomagnetic storms certain at some time

While EMPs would be dangerous, future Carrington Event sized geomagnetic storms are certain.  It's only a question of when, not if.  Random chance, but eventually we WILL be hit by another.  400 Chernobyls was authored by an MIT trained engineer.  It details much more destructive results than disabled cars.

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Boomer41
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Danger from EMP is voltage

Without going into lots of theory and mathematics, the danger from EMP is induced voltage, not current.

Most electrical and electronic devices are very resistant to destruction by current. The reason for this is that it is not the current per se which destroys the device but the heat generated by the current flow. Generally speaking the current has to flow for quite a long time c.f. the duration of an EMP, so this is not much of a danger.

On the other hand, excess voltage can kill electric and electronic devices instantaneously. Even a huge transformer can have its insulation destroyed in milliseconds by a tiny arc resulting from excessive voltage in the wrong place.

Faraday cages and grounding are potent protection, but not enough without voltage clipping devices and other means to limit voltage excursions. The only real solution is to have the over-voltage protection designed into the product. This is known as 'hardening' and is routinely applied to military equipment. Consumer electronics not so much.

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dpaull
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Re: How rooftop solar can prevent the apocalypse

Between the danger of EMP and internet hacking, I am much more concerned with the latter.

It appears that EMP is a serious problem but there are few persons (although many nations) that can pull it off.

I don't know how hardened our electrical grid is but my gut guess is that there are thousands of 'hackers' that could pull off an attack off if so inclined.

In today's world with the US terrorizing the citizens of other countries with drone attacks and other threats including economic destruction, the world is becoming a dangerous place indeed.

Even if I could protect my own premises from a long power outage, I cannot protect my food supply with what I can grow on my 7500 square foot lot for more than a few weeks. Life would get very difficult indeed.

Still, there are other less severe disasters, like a plane crash nearby, a hazmat spill, a forest fire or similar event where being able to live off grid for a modest time would be very helpful. So a battery backed solar power system seems like a doable thing. I have had an on-grid, 2500 W, solar system for a decade now so I am rather comfortable with solar. I would like to convert it to something that would switch to a battery backed up system but at my age (77) I'm not likely to get it done. As Chris so clearly points out, savers like me aren't earning much in our IRAs.

Dennis Paull

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Morpheus
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Boomer41 wrote:Without going
Boomer41 wrote:

Without going into lots of theory and mathematics, the danger from EMP is induced voltage, not current.

Most electrical and electronic devices are very resistant to destruction by current. The reason for this is that it is not the current per se which destroys the device but the heat generated by the current flow. Generally speaking the current has to flow for quite a long time c.f. the duration of an EMP, so this is not much of a danger.

On the other hand, excess voltage can kill electric and electronic devices instantaneously. Even a huge transformer can have its insulation destroyed in milliseconds by a tiny arc resulting from excessive voltage in the wrong place.

Faraday cages and grounding are potent protection, but not enough without voltage clipping devices and other means to limit voltage excursions. The only real solution is to have the over-voltage protection designed into the product. This is known as 'hardening' and is routinely applied to military equipment. Consumer electronics not so much.

I agree and disagree. The E field is going to generate direct potential differences on the electronics, its printed circuit boards, and wiring and potentially cause havoc. The associated H field does the same thing but by a different mechanism. A time harmonic magnetic field incident on conducting structures is going to induce an EMF in those structures, and that EMF is what is going to do the damage. So while you are correct in that voltage is the primary mechanism for which most electronics are destroyed in transient situations (most situations, but certainly not all), eddies generated by an H field will result in the same thing, but by a different mechanism and hence requiring a different approach to address. FWIW. My company does government and military communications and I have done a lot of work with hardening. 

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Morpheus
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OK, I got some PM feedback

OK, I got some PM feedback from a few friends on my long post and they basically said it sounded like cryptic Chinese. 

My apologies, I guess I have been in the lab too long surrounded by fellow geeks. :)

Let me clarify that entire post with simpler paragraph:

Many folks are quite familiar with the concept of electrical grounding such as the stuff you see in ordinary house wiring and appliances. That is AC (50-60 Hz) and sometimes DC (direct current).

EMP is a high energy radio frequency (RF) phenomenon and a high frequency event at that, and everything that you ever learned about ground for AC or DC completely falls apart at these frequencies. In other words, things that work for home wiring do not work at RF. And the surge protection circuitry that you all know about CAN and WILL fail in the presence of a strong RF electromagnetic field because that circuitry is designed to intercept the surge/voltage at the very high probability points of entry (they basically act like sentries that grab the unwanted incoming energy pulse, and shove it harmlessly to ground). With an RF field, the points of entry are virtually EVERYWHERE so unwanted high energy can get "behind" the sentry circuits and trash everything downstream from them. Worse, the electromagnetic physics of RF are completely different from AC or DC, so, and this is counterintuitive and a lot of folks have never heard this before, but trust me, a solid copper cable or spike to ground can actually "look" like an open circuit to RF energy. When I was talking about the car, to make it short, the 20" air gap ( 56 cm) between the car's chassis and the earth IS the ground, so a closed circuit is completed, and that voltage field can cause current to flow ( ground enables current flow as you remember) in crazy unwanted portions of the car, including sensitive electronics, and more importantly the ground can set up voltage differences across sensitive electronics, thus potentially trashing them. So that's how a car, with 4 rubber wheels can still be disabled with EMP.   

My entire point was to caution folks not to feel a false sense of security about solar panels because they are earth grounded or because they have surge protection built into them. But, a little long-winded verbosity basically defeated my purpose. Sorry about that. :( 

I guess I got a bit excited about this topic because, believe it or not, my present occupation is research on electromagnetic hardening of power management systems for electromagnetic interference (EMI), electromagnetic compatibility (EMC) and electromagnetic emissions (EME). Boy, talk about stumbling on a topic that you rarely talk about outside of work. 

Anyways, sorry for the mumbo jumbo.

Finally, I got a taste of my own medicine the other night when reading a bunch of folks talking about monetary theory. A few went right into the shop vernacular and I was left scratching my head with a "Saayyy whaaaa???" kind of dumbfounded look at the screen, completely clueless about what the hell they were saying.  Then comes along a poster, who while very knowledgeable translated a lot of that foreign language into common analogies that I could relate to, and benefit from.

 THAT also got me thinking about that post that I wrote. 

So, my bad. I will try to be more thoughtful next time. 

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Thrivalista
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Thanks for both!

Morpheus, I *appreciated* your technical post even tho' I understood *very* little of it. And I appreciated the lay person interpretation even more. :D Thanks for your passion and your willingness to clarify.

Thriva

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Oliveoilguy
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Morpheus.....Thanks for

Thanks for the layman's explanation. Very easy to follow.

So for those of us with a sizable investment in Solar, is there anything we can do on a practical level to protect our equipment? I would a assume that distance from the center of the EMP would determine extent of damage. Is that correct? or is it an all or nothing event?

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silvervarg
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Re: How to protect solar installation

As has been stated above it is very hard to make something that is not sensitive to EMP at all.
But depending on the source of the EMP and the distance from your solar installation the magnitude can be drastically different.
If an atom bomb is detonated right above your installation you simply had a heck of bad luck. If your not a military installation I don't think you should worry about that scenario.

What seems reasonable is: ground edges of solar panel. This will give some protection.

The most sensitive part of your system is the regulator, and protecting it well is next to impossible. A better approach is to have a backup regulator that is not plugged in and stored in a metal container.
It will "only" save you from one EMP, but that goes a long way.
If the EMP comes from strong solar flares I would advice the you wait a week before connecting your spare regulator as it is likely that you get several solar EMP's during a few days.

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