When it comes to keeping airport runways clear of ice, there are several options, including the use of chemical, thermal, electric and microwave technologies. All of these methods can be expensive, as they require either a considerable amount of electricity, or a number of human workers. Engineering researchers at the University of Arkansas, however, are developing a new system that would use the freely-available power of the Sun to keep runways from freezing up.
The research team currently have a two-layered section of runway set up to test their system. The lower layer consists of a single slab of non-conductive concrete, resting on a bed of gravel, and measuring 20 x 24 feet (6.1 x 7.3 meters). On top of that is a second layer of concrete, made up of 12 panels each measuring 4 x 10 feet (1.2 x 3 meters). Ten of those are made from a special concrete that conducts heat, while the other two are made from regular concrete, to act as controls in the study.
A nearby photovoltaic system converts sunlight into energy, stores that energy in batteries, and then provides power to electrodes embedded in the conductive panels. In tests performed so far, the conductive panels have been much quicker to melt ice that was applied to them by researchers.
In general, however, the heat flow across the entire test section has been uneven, with more heat concentrated closer to the power source. According to project leader Ernie Heymsfield, this problem will be addressed by modifying the configuration of the electrodes.
Testing of the University of Arkansas technology will continue throughout this winter.