Good Thinking

Electrified concrete may keep airports ice-free

Electrified concrete may keep ...
The testbed at Des Moines International Airport
The testbed at Des Moines International Airport
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A thermal image of the conductive concrete
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A thermal image of the conductive concrete
The testbed at Des Moines International Airport
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The testbed at Des Moines International Airport

It's not just airplane wings that need to stay ice-free in the winter – it's also pretty darn important that the runways not be icy, either. With that in mind, an Iowa State University team led by Prof. Halil Ceylan has developed a new type of electrically-conductive concrete that melts snow and ice. The material is currently being tested at Des Moines International Airport.

Installed on the apron of the airport's general aviation area, the testbed takes the form of two side-by-side slabs of concrete, each measuring 15 x 13.5 feet (4.6 x 4.1 m).

Each slab is 7.5 inches thick (19 cm), and consists of two layers. The bottom 4-inch (10-cm) layer is made up of regular concrete, while the top layer consists of 1 percent carbon fiber combined with a special mix of cement, sand and rocks. Sandwiched between those layers are six electrodes (per slab) that are hard-wired to a power supply in a nearby hangar.

When the electrodes are remotely powered up via an app, they send an electrical current through the top layer. The carbon fiber content makes the concrete electrically conductive, yet there's still enough resistance that heat is generated. That heat makes the surface of concrete hot enough to melt away accumulated ice and snow, yet still safe to touch.

A thermal image of the conductive concrete
A thermal image of the conductive concrete

A hydrophobic coating is going to be added to one of the test slabs soon, helping the material to repel moisture.

Using 333 watts per square meter for seven hours, the concrete has a claimed operating cost of about 19 cents per square meter. Seven hours, says Ceylan, is "way more than enough to melt an inch of ice or snow." Although it would be more expensive to install than regular concrete, it would reportedly reduce the need for plows, de-icing chemicals, and wastewater treatment of chemical runoff.

In fact, it may be best suited to congested areas such as aprons (as opposed to the main runways), where there's too much traffic for plows to operate. It could also find use in the sidewalks outside of airports.

Ceylan's research is part of a larger program being run by the Federal Aviation Administration, which has also been testing a different type of ice-melting concrete developed at the University of Nebraska-Lincoln. That material conducts electricity via a mixture of steel shavings and carbon particles.

Source: Iowa State University

11 comments
LarryWolf
I'm sure it would be too expensive to lace an entire airport with the stuff and NO it won't cut down on deicing--that isn't for the runways it's for the planes.
RayCrabtree
One could sell a lot of this concrete in Ohio, among other places.
dburdsal
Larry, the article never said it was for "deicing", it said it was for keeping it ice free... To author, don't you think people would like to know how much more expensive it is than regular concrete? It obviously could be used for places other than airports. Saying how much it costs to power up for 7 hours is only a third of the information you should have supplied. How much more than regular concrete is the more obvious question that needs answering before anyone can have more than a passing interest, especially since there have been YouTube videos of heated concrete for years. Not carbon fiber obviously but assuredly less expensive. It would have also been nice if you could have asked how much airports could save by not using all of the equipment you mentioned.
eMacPaul
@dburdsal, actually the article does say it would cut down on the need for de-icing chemicals.
dugnology
Can this be used for radiant heat in a house?
Douglas Bennett Rogers
A major airport runway is a high value application. It is usually 16 in. of reinforced concrete. The carbon reinforcement could probably be justified. Might be good in bridges for the same reason.
bergamot69
Rather than using expensive electricity to heat the concrete (19 cents per square meter is a huge amount when you consider just how much there is to heat), why not use geothermal heat (ground source) and embed piping in the concrete? That way you aren't paying for the heat, only the electricity needed to pump the heat from down below. Even so, would be a hugely expensive undertaking. But consider the costs of closing down a major airport such as London's Heathrow versus the cost of installation.
Observer101
Very expensive to operate... Why not install radiant heating tubes in the concrete and build vast storage and heat transfer modules under ground, and under the frost line, where the temperature remains constant year round.... Pumps would be required to circulate the anti-freeze/water solution, which would be cheaper than the system in discussion.
Eugarps71
We had a group at the University of Alaska develop something like this using a carbon fiber tape to heat asphalt or concrete several years ago. I believe they ended up starting a company.
michael_dowling
There is already a technology to keep runways ice free. It's called Solar Roadways.