Will an electromagnetic pulse affect my solar panels?

“In the 10 years since I first fell in love with solar technology, I have been answering questions from pioneering adopters and thought I’d heard them all. That was until I was asked “whether an electromagnetic pulse will affect my solar panels?”

Sunspots produce X-flares.

Sunspots produce X-flares.

In celebration of Heat my Home’s 10th birthday, I will answer this most unusual of questions.

Upon further enquiry I discovered the nature of this question stemmed from worries about the current peak solar activity and more than usual solar flares which are currently being ejected out by the sun.

If one of these super-massive coronal mass ejections (CMEs) were to give the Earth a direct hit, then this would bath the planet and our solar panels with electromagnetic waves, but not pulses

The question was valid, and so I set out to investigate the answer to this somewhat unusual question, but there is a difference between CMEs and electromagnetic pulses (EMPs) which is a by-product of a nuclear weapons discharge and other modern day weaponry if you believe the rumours.

As always with questions like these, there is good news and bad news.

The least likely occurring threat to your solar technology could be a solar mass ejection hit, but very likely will disrupt traditional power lines.

The largest known CME to hit the earth happened in 1859 which disrupted the telegraph system of the time. With today’s technology, a CME could cause many times the amount of damage to power lines and infrastructure. Smaller known CMEs have occurred in 1972 and 1989 and the good news is that photovoltaic solar panels were not reported as being affected at these times.

The cause of the damage comes from the surge in power which the power lines and transformers are exposed to when the unusually high volumes of solar particles charge the network.

If a CME were to hit your solar panels, then the inverter that is load-protected and fused would cause your system to shut down automatically. If your inverter has been specified correctly, then in most cases, your inverter will be over-specified for your system anyway. Worst case scenario will mean your inverter will blow a fuse and a simple fuse change will get your solar panels back to full working order.

If the outside power network is affected by outages such as those experienced by Quebec in Canada in 1989, then your photovoltaic system will automatically shut down to protect itself. Once the power companies engineers have completed there repairs then your system will automatically start-up again.

For owners of solar heating panels such as evacuated tubes then the same is true with your solar controller that is protected by your home’s internal trip switches. No known issues are known to affect these types of solar heating technologies.

Satellite technology encompassing PV solar technology have been circulating our planet since the 1950s while enduring varying amounts of solar weather and most are still operational today, so this, I think best proves that you have nothing to worry about, but everything to gain when installing this misunderstood technology.

A threat to your solar technology could be an electromagnetic pulse, but is very unlikely

And returning to the original question, a small electromagnetic pulse can occur naturally via a lightning strike, but like the lottery jackpot, you have a very small chance of coming across one. This brings us to man-made EMPs caused by modern weaponry.

In the event of such a strike, the affected area will see most forms of modern and delicate electronics damaged. An EMP strike works by reverse magnetising and overheating nearby electrical systems. In other words, your Iphone will be toasted.

Solar panels are vulnerable to the EMP effect, but the real danger to most people comes not from a direct strike, but from the indirect effects which will occur later.

The only way to protect your system is to incase your inverter inside a faraday cage, but protecting yourself from the indirect effects would be much harder to achieve.

Even if your solar panels do manage to survive any future EMP attack, your other circuit based technologies around the home will almost certainly not survive either.

Threats to our modern age come in many varieties of ways, but EMPs and CMEs are almost certainly at the lower end of the threat spectrum, so I can confidently say that investing in a solar panel installation is still an important way to future proof your life.

Over the last decade I have helped many thousands of people decide on a solar future and I hear people say on a regular basis that they wished they had “installed sooner” as will others over the next decade who wish to become less dependent on increasingly expensive traditional energy.

The sun is always your friend with solar panels on your roof.

It’s not a question if you install them, but more a question of when you install them?


"Feel the pride."

Stuart Lovatt on
Founder of Heat My Home.

  • Barney Quinn

    Thank you for one of the most accurate comments I’ve seen on the EMP issue. All of your assessments are correct. I’m a CATV engineer (Cablevision) and electromagnetic fields, irrespective of how they are generated, are essentially RF energy that generates currents in conductors those fields intercept. Conductors are essentially antennas. Their orientation, length, composition, affect how much voltage will be generated by a passing magnetic pulse.

  • Arthur Bradley

    Great comments. People often misunderstand the effects of solar electromagnetic events from those of a high-altitude nuclear-generated EMP. Solar events are primarily a threat to very long conductors (i.e., our electrical grid), whereas a nuclear-generated EMP would have some very high-frequency (short duration) components that could indeed damage very small-scale electronics. The other comment I would add regarding solar arrays is that while the PV cells themselves are low-impedance devices designed for high currents, the bypass and blocking diodes are not as robust. Their failures introduce different effects, from lower efficiency, to complete system failure, depending on the type of failure (open or short). Of course, the charge control circuitry is also susceptible. P.S. I am also an EE (PhD), working for NASA.

  • Tim

    Just disconnect your solar panels from your inverter at night…they are not being used anyway…the problem is delicate electronics in your solar converter and inverter and your battery bank.

  • David Cottrell

    I am no engineer, but it is also my understanding that many vehicles would not be affected due to the fact that they are not grounded and are in a big metal box. Again, I am not sure the relative aperture of a solar system (off-grid). But given that the inverter, charge controller and such are wired into the solar array, wouldn’t the solar array act as an antennae sending the pulse along he wiring to the electronics connected to it? “Faraday cage” or not, if they are wired to an antennae, they would get smoked, right? I have actually had the experience of an indirect lightening strike creating a pulse and frying upstream systems and some of the downstream panels (the newer ones with more sensitive electronics). This kind of thing jumps right over fuses (many were untripped and in tact) and smokes everything. How similar is that to an EMP?

  • Tor

    I agree with what you are saying. The point of my original comment was to call out the nonsense being perpetrated about “reverse magnetization” and to point out that not every electronic circuit will succumb to the EMP as most are let to believe. The E1 pulse generated by Compton electrons interacting with the Earth’s magnetosphere is the greatest threat and most difficult to counter in that it comes without warning (unlike a coronal mass ejection from the Sun), and is so intense while being so brief. None the less, items of small aperture will likely survive with minimum or no shielding (watches, etc.).

  • Al Olmstead

    I am totally off grid but have a 5′ long pure copper stake driven down into my back yard. Will I eliminate both of these dangers by having the entire system (panels, charge controllers and inverter) inside a ferous mesh, such as heavier poultry fencing, and then grounded to my copper stake?

  • Tor

    Correct! If you had advance notice of a potential EMP attack, you could disconnect from the grid (if your system works part time on/off the grid), or just be totally grid-independent.

  • Nick

    Which may be blocked by a capacitance grounding system, correct?

  • Tor

    I am an electrical engineer and faculty member at a major university… and “An EMP strike works by reverse magnetising and overheating nearby electrical systems” makes no sense. First, EMP is a momentary increase in electromagnetic field strength that can induce over-voltage conditions in sensitive circuits which cause either momentary errors (such as forcing the reset of a microprocessor), or causing breakdown of semiconductors (such as in the front end of sensitive receivers)… nothing is “reverse magnetized”. There is a lot of hype and misunderstanding about EMP effects and fictional sources like “One Second After” are not at all a source of valid information. Solar systems (PV arrays and associated electronics) are fortunately relatively “low impedance” circuits that may not be adversely effected by an EMP blast depending primarily upon distance from the blast. The reason that CME and EMP can disrupt grid power systems is that the grid is like a large antenna which collects energy over a large area and can therefore concentrate large currents within the network. People who talk about watches stopping due to EMP, etc., don’t understand that the aperture size of smaller objects (i.e., their ability to collect electromagnetic energy like an antenna) is insufficient to cause damage. Also, watches, cars, and even your solar inverters are usually encased in metal (a Faraday cage) which will limit the induced over voltage from an EMP. The greatest threat from an EMP (unless its right over top of you, and then you have other more serious issues to deal with) is current surges coming into your system from the grid.

  • I too am facinated by how fragile all this around actually is. A man-made EMP attack will likely be a high conurbation area like London, and although this would affect people living ‘down south’, more northern/Scottish areas could be less affected like Canada after the Quebec incident in 1989.

    My point is, a country which is “solar panelled up to the max” would be in a much better position to weather such an attack than a country without a mix of power generation.

    But yes, if it actually happens, or if the sun sneezes in our direction, then its gonna get messy.

  • NTC

    I recommend you read “One Second After” by William Forstchen. As NK and Iran become nuclear and missile capable, an EMP attack is the most potent asymmetric weapon they could ever hope for. Your dismissive answer reveals a lack of knowledge.