Young researchers created a superconducting heat ink that functions as a solar heater. It heats water up to 68 degrees Celsius and is 40 percent cheaper than commercial inks.
“A pipe exposed to the sun reaches a temperature of 40 C°, if we add the superconducting ink the temperature increases 70 percent and reaches 68 C°,” says Sandra Casillas Bolaños, master at the Technological Institute of the Lagoon (ITL), in north of Mexico, and head of the project.
She explains that the ink acts as a boiler that contains nanoparticles activated by solar energy and increasing the temperature.
The ink is made of two layers, the first is an internal magnetic titanium nanoparticle, which is responsible for trapping the heat and the second is external and consists of a coating of tungsten (filament in light bulbs) which researchers transform into a nano salt and adhere with polyvinyl alcohol, to finish with a layer of copper.
Casillas Bolaños states that by a treatment called burnishing copper blackens in order that trap and retain heat inside the particles. “Thus the center is heated more intensely: first the titanium, then tungsten and finally the copper”.
The project has been developed for two years and the product is classified as an ink because it uses a series of solvents making it fast drying and with an odor similar to hair dye.
The ink is applied on the surface of a conventional pipe that carries water and to potentiate the heat, students working on the project with professor Casillas Bolaños in the nonmetallic materials field, put two layers of PET bottles over the tubes in order to create a greenhouse effect and raise the temperature faster, as well as protect the ink from outdoor wear.
The technology has been implemented in some houses, where, by flowing for five meters water at 68 C° is obtained instantly, and even in cloudy weather the ink nicely captures the heat.
Sandra Casillas adds that the ink was implemented in a major sports complex of the city to heat the pool, where two million cubic meters of water are heated from 26 to 37 C°.
To achieve this, the researcher and her team placed tubes covered with ink on the edge of the indoor pool and a pump pulls the liquid from seven o’clock until the sun sets. As it flows, the water is heated and reaches the ideal temperature.
The ink is in the process of patenting and is intended to be market at 600 pesos a liter (about 40 dollars); however, for house piping only 150 pesos (10 dollars) are invested because very little is needed, says Casillas Bolaños.
The professor at ITL says that the difference of this technology against the ones that already exist in the market is that those are made with expensive metals and the one created by her team contains tungsten, which is 40 percent cheaper.
The next step is to optimize it and create more ink in large volumes, because it is currently done step by step and each nanoparticle is fine tuned.