Applications of nanotechnology are delivering both expected and unexpected solutions to the challenges that are facing society. Nanotechnologists are finding applications in traditional energy sources and are greatly enhancing alternative energy approaches to help meet increasing energy demands. More products, with a variety of applications, are being developed to save energy and use it more efficiently. An important area of application is in improving energy transmission.
Energy transmission is the movement of energy, which could be electrical or petroleum, from a generating site to the respective stations for use. A network of transmission equipment is established; electrical cables are used for the transmission of electrical energy and pipelines are used for the transmission of petroleum.
Aluminium conducting wire with steel reinforcing has always been the standard overhead conductor for the transmission of electrical energy. However, long-distance transmission incurs significant losses due to electrical resistance. This raises a need to explore more efficient materials in the transmission of electricity. The application of nanotechnologies to energy transmission could potentially impact existing technologies through the use of innovative materials with enhanced properties. Quantum wires transfer electricity with significantly reduced losses when compared to conventional conductors, which enables power transmission at higher power densities. Such efficiencies may relieve transmission congestion and optimise the need for certain transmission equipment. Replacing existing conducting wire with quantum wire could revolutionise the electrical grid, as the electrical conductivity of quantum wire is higher than that of copper wire. Quantum wire is also one-sixth of the weight of copper and is twice as strong as steel.
Examples of nanoscale materials with the potential to significantly impact the transmission of electrical energy in the foreseeable future include, but are not limited to, carbon nanotubes, buckyballs and quantum dots. Carbon nanotubes are a type of fullerene molecule formed when atoms of carbon link together into tubular shapes. They are generally extremely light, strong, and resilient, and some are more electrically conductive than steel or copper. Buckyballs are hollow spherical molecules composed of a large number of carbon atoms. These fullerenes are used in mechanical and semiconductor operations. Quantum dots are semiconductor crystals with electrical and optical properties that may make for more efficient lighting and solar collection, and that also make them attractive for use in electricity transmission.
Nanotechnology may also help improve the transmission of petroleum distillate fuel and natural gas by prolonging the maintenance lifecycle, reducing repairs and restricting the possibility of environmental destruction to the pipelines used for transmission. Nanomaterial coatings diminish wear and tear, corrosion and erosion because nanomaterials can be stronger per unit volume than other materials. Most of the known nanotechnology applications for pipelines involve material coatings (insulation, corrosion, and multipurpose). Nanocoating of metallic surfaces aids in attaining low friction and improving oxidisation protection.
Another prospective application for nanomaterials in gas or liquid transmission is nanosensors. They have the potential to reduce environmental damage by detecting impending petroleum or gas leaks. Oil spill remediation with nanomaterials can lessen the damage to the pipelines, should a leak occur.
Due to their extremely small size and relatively large surface areas, nanomaterials may interact with the environment in ways that differ from more conventional materials. Potentially harmful effects of nanotechnology could result from the nature of the nanoparticles themselves. According to the National Nano Technology Strategy issued by the Department of Science and Technology (ISBN 0-621-36395-2), not many studies have been done to assess the negative impact of nanotechnology on energy transmission and is therefore an area of research that the government is investing resources in.
It is clear that South Africa cannot afford to ignore nanotechnology. There are many potentially revolutionary applications of nanotechnology in all aspects of the energy cycle, including energy transmission.