Graphene to Revolutionize Power Lines?
April 29, 2014
Polish companies are preparing to launch production of new-generation power cables partly made of graphene, the revolutionary new material that is ultralight, flexible, over 100 times harder than steel and an excellent conductor of electricity.
This new technology promises to revolutionize electricity transmission systems. Prof. Tadeusz Knych from the University of Science and Technology (AGH) in Cracow, southern Poland, heads a 10-member team of researchers from the university’s Department of Non-Ferrous Metals who are working to modernize Poland’s overhead power line system in order to protect the country—and in the future also other countries—from the bane of blackouts.
It is already known that graphene is a highly efficient conductor of electricity, the Polish researchers say. They intend to put this property of graphene to good use. They are seeking to develop a remarkable composite that will combine graphene with copper and aluminum, metals that are traditionally used for electric cables and wires. Once they manage to obtain such a material, they hope to use it to make power lines that transmit electricity more efficiently.
The planned combination of graphene with copper will yield a composite called CuGRAF, and the combination of graphene with aluminum will result in AlGRAF, the researchers say. They expect that these composites will have above-average electrical and thermal conductivity. Unlike traditional power lines, the new cables will not lose their properties under the influence of high temperature. With the transmission capabilities of the existing network enhanced thanks to the use of graphene, it will no longer be necessary to develop the country’s power transmission infrastructure as intensively.
“The demand for electricity is growing around the world,” says Knych. “Both production and transmission are challenging. Currently used cables convert part of the energy into heat, which leads to heavy losses. When the power lines become hot, they release heat into the environment. Another side effect and potential danger is that, at high temperature, their strength and resistance decrease.”
The project on which Knych is working—entitled “New wires from metal-graphene composites with increased electrical conductivity intended for power lines”—began in December and will last three years. It will be financed by the National Center for Research and Development (NCBiR) together with cable producer Tele-Fonika Kable and Polish power grid company Polskie Sieci Elektroenergetyczne. They will provide more than zl.5 million between them for research related to the project. The NCBiR will contribute zl.4.6 million. Another member of the research consortium is the Institute of Electronic Materials Technology (ITME) in Warsaw.
The Cracow researchers have designed and built new research stations for the metallurgical synthesis of graphene with copper and/or aluminum. Copper and aluminum, alongside silver, are the best electricity conductors, so they will likely continue to form the basis of power lines in the future.
“We need to develop the concept of a unique composite,” says Knych. This is difficult because graphene melts at a temperature more than three times higher than copper and more than five times higher than aluminum. This means that it will still be in a solid state long after the metal has melted. This is not the only difficulty. Another problem is that it is necessary to make sure that graphene is distributed across the matrix in the right way during the solidification of the composite. This is not easy either because the density of copper is eight times greater than the density of graphene. Graphene is very light and will gather on the surface of the liquid. It is thus necessary to ensure the proper arrangement of the atoms of these two elements. The first laboratory tests will begin in the middle of the year.
The Institute of Electronic Materials Technology produces graphene with high electrical conductivity—perfect for the project—according to its own patent. The development of graphene production methods has been a major focus of the institute’s work in recent years. It is best positioned to handle industrial production of graphene in Poland. Other companies produce graphene—which is an allotropic variety of carbon—primarily for laboratory tests.
The project also involves cable producer Tele-Fonika. The company will produce wires and cables from the obtained material. In turn, Polskie Sieci Elektroenergetyczne, the owner of the Polish power transmission system, is tasked with reporting on what the Polish overhead power line system needs in order to be improved. The company’s experts are currently drawing up goals to ensure efficient transmission of power in Poland. The AGH researchers will have to meet these goals.
All countries have their own energy security scenarios. The main problem is funding because composites that include graphene are expensive. But even without that, the most modern power cables are from seven to 10 times more expensive than standard ones. They must meet stringent quality requirements if they are to help prevent problems such as blackouts.
The new power lines will contain much less graphene than the base metal in terms of mass. But in terms of volume, graphene—which is less dense—will prevail.
Graphene is a new wonder material that could have myriad hi-tech applications and may even replace silicon in the electronic devices of the future. Transparent, flexible and durable, graphene offers a huge range of potential applications in industries including aeronautics and the automotive industry, in addition to electronics, energy generation and storage, medicine, materials engineering, and environmental protection.