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How is green nanotechnology being used?


Green Energy Comes in Small Packages

Nanotechnology promises to improve our environmental outlook by getting us more bang for our energy buck and reducing our reliance on fossil fuels. To see how, consider your family car. Vehicles constructed even partially from nanomaterials can be lighter, and therefore more fuel efficient, without sacrificing strength or safety. Under the hood, nanofilters can take the gunk out of your go-juice, so that your ride pumps out less pollution and suffers less wear and tear on its engine. Nanocoatings can make windshields and paint jobs self-cleaning to boot.

Green machines like hybrids and hydrogen vehicles stand to benefit even more. Engineers are already developing fuel cells packed with carbon nanotubes to store hydrogen and increase reactivity. Carbon nanotubes may also one day replace expensive platinum as the hydrogen fuel cell catalyst, driving down costs [source: Battersby].

Thanks to nanophotonics, the study of light's behavior at the nanoscale, nanotechnology has your energy needs covered at home and in the office as well. Researchers have developed windows, paints and film coatings that they can "tune" to reflect or transmit specific wavelengths of solar radiation, including the infrared energy that we experience as heat [source: Feder]. It's like turning your whole house into a sun shade during the summer and a space blanket in the winter.

More efficient nanoelectronics will translate into gizmos that gulp less energy and store it more efficiently -- a real boon in our gadget-gonzo age [source: Chmiola]. Quantum dots, aka semiconducting nanocrystals, could soon power a display technology that packs both the efficiency and long life of organic light emitting diodes (OLEDs) and the durability of cathode ray tubes (CRTs) and liquid crystal displays (LCDs) [source: Dumé].

Farther up the energy pipeline, nanoscience offers hope for amping up alternative energy sources. Solar panels printed using nanoparticles require fewer components to operate, meaning there is less to repair, maintain or later bury in a landfill. With lower operational costs, such panels can output less power and still be profitable [source: Markoff]. Researchers have also dreamed up a way to extract energy from the salinity difference between seawater and river water. The technique relies on batteries made up of electrodes bristling with nanorods [source: La Mantia].

By now you're probably thinking, "That's all well and good, but how green can nanotechnology solutions be if building them creates a toxic mess?" As we'll see in this next section, many scientists and engineers are concerned about these very issues, and are striving to make nanotechnology greener from the get-go.