EMPs from nuclear detonations hundreds of miles away can still fry power grids. This July 25, 1946 … [+]
The potential threat of an electromagnetic pulse (EMP) to our network, either as an actual weapon or as a result of natural phenomena such as a giant solar flare, occasionally pops up on the news.
EMPs, also known as transient electromagnetic interference, are brief bursts of electromagnetic energy. It is one of the things that many people think is wrong, exaggerated, or a conspiracy theorist’s dream. But a US commission to assess the threat to the United States from EMP attacks says they are real.
EMPs can either be natural, from things like extreme solar geomagnetic disturbance, or human hands like a large thermonuclear detonation or cyber attack. If coordinated with physical attacks, things could get really sticky very quickly.
The phenomenon of a large electromagnetic pulse is not new. The first man-made EMP occurred in 1962 when the 1.4 megaton thermonuclear weapon Starfish Prime detonated 400 km above the Pacific Ocean.
A hundred times bigger than what we dropped on Hiroshima, Starfish Prime resulted in an EMP that caused electrical damage nearly 900 miles away in Hawaii. It knocked out about 300 street lights, set off numerous burglar alarms, and damaged a telephone company’s microwave link that disrupted calls from Kauai to the other Hawaiian islands.
And from a distance of 900 miles.
On the natural side, an unexpected geomagnetic storm triggered an event in the Hydro-Québec electricity system in 1989 that resulted in a complete collapse in 92 seconds, leaving six million customers without power. The storm resulted from the sun ejecting a trillion cubic kilometer cloud of superheated plasma or ionized gas.
Such storms occur about every 60 years, and in 1989 we were still a long way from being as electrified and electronically connected as we are today. Or how we will be in 30 years.
Solar events are considered to be the most likely EMP events.
So what can we do to prepare? Shield them.
Electromagnetic shielding prevents electromagnetic waves from affecting sensitive electronics – from televisions and microwaves to cell phones and baby monitors, as well as the critical computer processors of modern smart devices. Traditionally, this was achieved through built-in metal sieves or metal housings, so-called Faraday cages.
Paints and coatings that conduct electricity and magnetic fields can be critical to protection … [+]
But maybe we can just paint over it. Painting the shield ensures more thorough coverage at a much lower cost. In addition, conductive paint can also dissipate heat from sensitive electronic devices, regulate their temperature and prevent the thermal shutdown of modern electronics.
There is a class of colors called Smart Paints that can do a lot more than just cover a surface and protect it from corrosion or rotting. These paints may contain additives that cause them to conduct electricity or heat.
They are generally used for things like providing low temperatures to melt snow from sidewalks and stairs, or fogging glass to high voltage industrial applications at high temperatures. They can easily adhere to most surfaces including concrete, metal, glass, and composites.
Exactly from the things that make up our network – transformers, junction boxes, antenna cables, etc.
These colors are actually thin film conductors. But anything that conducts an electric field also conducts a magnetic field in an orthogonal direction.
So painting a large transformer this color is like putting a Faraday cage on top, but cheaper.
To see if this is possible and how it could be done, we can look at the guidelines for EMP protection and resilience for critical infrastructure and devices.
These guidelines were developed and created at the National Cybersecurity and Communications Integration Center, Arlington, to meet the Secretary of Homeland Security’s responsibility to establish a national effort to address devices against electromagnetic pulse threats (EMP).
Table 1 of the report offers four levels of EMP protection based on the time it takes to get back online, from seconds to minutes to hours to indefinitely. These also tend to be followed with costs. A shielding of around 80 dB to 10 GHz offers the highest EMP protection.
In tests at the US Air Force Research Laboratory, the latest SmartPaint electrical paint consistently reached 3 GHz with an average shielding of 91 dB with four layers of paint, about as effective as a 1/2 inch aluminum / steel plate. But while it did well above 1 GHz on the high end, it didn’t do as well on the lower RFI end. It was better at microwave frequencies, where ceramic plates coated with smartpaint reached up to 1100 ° F.
Another potential product comes from Nanotech Energy Inc., the leading manufacturer of graphene. Their Nanotech EMI Armor Paint & Sheets debuted last year. These are graphene-powered coatings and films for shielding against electromagnetic interference and radio frequency interference, as well as for thermal management.
The EMI shielding line currently includes six products – all of which are highly conductive and provide great external EMI / RFI protection while preventing internal EMI / RFI leakage.
Graphene is the thinnest, strongest, and most flexible material known. It is 200 times stronger than steel, 97% transparent, extremely light, flexible and stretchable. Depending on the product used, the products can be sprayed, brushed, rolled or dip-coated onto various surfaces such as glass, plastic and metal.
In addition to graphene, these products can contain polyurethane with silver-coated copper flakes or polyester binders, which offer exceptional flexibility and conductivity.
More testing is needed to test lower ranges (MHz, KHz) as well, but this is just the beginning. A key question is how thick, ie how many layers, the paint needs to be and whether it is sufficient to achieve different desired protective measures on different targets.
But electrical painting seems to be more practical, faster, and more economical than making thick copper or aluminum boxes around the country’s entire electrical infrastructure.