RESEARCH
New insulation material: more efficient electricity distribution
Illustration: Chalmers University of Technology
High-voltage direct current cables (so-called HVDC cables) which can efficiently transport electricity over long distances play a vital role in our electricity supply. Optimising their performance is therefore an important challenge. Recently Chalmers University of Technology, Sweden, presented a new insulation material up to three times less conductive, offering significant improvements to the properties and performance of such cables. To a future world, powered by renewable energy, efficient long-distance transport of electricity is essential. Renewable energy sources such as wind and solar farms, as well as hydroelectric dams - is often located far from cities, where most of the demand exists. HVDC cables with an insulation layer can be buried underground or laid on the
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seabed. During transport, as little energy as possible should be lost. Insulation plays an essential role in this. Researchers of Chalmers University of Technology now present a novel insulation material based on polyethylene, which is already used for insulation in existing HVDC cables. Now, by adding very small amounts - 5 parts per million - of the conjugated polymer known as poly(3-hexylthiophene), the researchers were able to lower the electrical conductivity by up to three times. The additive, also known as P3HT, is a widely studied material, and given the tiny amounts required, opens up new possibilities for manufacturers. Other possible substances that have previously been used to reduce the conductivity are nanoparticles of various metal oxides and other polyolefins, but these require
significantly higher quantities. Conjugated polymers, such as P3HT, have been used in the past to design flexible and printed electronics. However, this is the first time they have been used and tested as an additive to modify the properties of a commodity plastic. The researchers therefore believe that their discovery could lead to numerous new applications and directions for research. The article ‘Repurposing Poly (3-hexylthiophene) as a Conductivity-Reducing Additive for Polyethylene-Based High-Voltage Insulation’ was published in Advanced Materials. It’s online> More at Chalmers>
