Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Long-distance transport of green power: First successful testing of a 20 kA superconducting cable

11.03.2014

The growing deployment of renewable energy sources (RES) will have to be accompanied by a significant expansion of the electricity grids.

The places where the generation of energy from wind, solar or hydro would be most economically competitive are often located in remote areas (offshore wind for example), distant from the densely populated zones where the energy is needed.


The test station at CERN

In this perspective, the Institute for Advanced Sustainability Studies (IASS) together with CERN (European European Organization for Nuclear Research) reached an important milestone on February 20th with the successful testing of a prototype superconducting cable able to carry 20 kA of current.

Nobel Laureate and IASS Scientific Director Carlo Rubbia commented on this result: “This is really a breakthrough. For the first time, we have a real cable which offers a practical way of transporting large amounts electricity over long distances, using a simple configuration and cheap, widely available materials”.

The experiment, which was the first of its kind, took place in the laboratories of CERN in the framework of an IASS-CERN collaboration aimed at assessing the potential of electric power cables based on the superconducting material magnesium diboride (MgB2). The tested configuration consists of two very thin, 20 m-long MgB2 cables combined in series for direct current (DC) transmission, and placed inside a semi-flexible cryostat that uses helium gas to maintain the very low temperatures required to enable superconductivity.

During this latest test, the cable setup, which has a total diameter of only 16 cm, housed two MgB2 cables able to transfer a current of 20 kA at low temperatures of about 24 K, and showed very good and homogeneous superconducting properties.

In the future, this type of superconducting cable could be installed underground, with periodically spaced cryogenic stations; a technology that is similar to the widespread natural gas distribution grid. It would achieve capacities of 2 to 10 GW, or even higher, with operating voltages that can be tailored for optimised performance. To give an example, the planned German Suedlink transmission line, meant to connect the North Sea to Lower Fraconia, would have a capacity of 4 GW with a subsequent uprating to 12 GW by 2032 (Netzentwicklungsplan).

In comparison to the alternatives, these superconducting underground cables would provide several significant advantages ranging from efficiency, cost, ease of implementation and environmental impact. First of all, superconducting materials like MgB2 are able to transmit electrical power without incurring resistive losses, which on the contrary affect conventional HVDC (and AC) lines and increase with the length of the line. Fewer losses translate into increased economic profitability and better resource management, as less energy is wasted.

Another distinctive feature of MgB2 SC cables is their small size: the whole installation for a 4 GW 800 km-long bi-polar cable, including the cryogenic envelope, is expected to have a total diameter of about 30 cm, which is less than most existing natural gas pipelines and much smaller than the corridor width needed for standard HVDC underground cables (about 20 m for 10 GW in central Europe). These latter also suffer from heat dispersion issues that severely limit the maximum capacity and have negative consequences for soils; in the case of SC cables, this drawback is entirely eliminated.

Finally, the choice of underground cables instead of overhead lines carries the usual benefits: it enables underwater crossings and transmission within densely populated areas and avoids the need to build massive transmission towers. Public opposition to invasive and environmentally harmful overhead lines has become an important factor in the decision-making process regarding grid expansion projects. Therefore, the search for technological alternatives is paramount. Additionally, existing rights-of-way could be used to install SC cables.

The first cost estimates show that the investment costs for the construction of a 4 GW MgB2 transmission line would be up to several times lower than for a standard ±320 kV HVDC underground cable, and competitive with HVDC overhead lines. The relatively low cost of MgB2 SC cables stems from their low cost per kA and meter (due to inexpensive materials) and simple manufacturing process.

Presently, IASS and CERN are pioneering the development of MgB2 cables. The results of the recent test have confirmed the promising nature of magnesium diboride, especially with respect to alternative materials like the expensive high-temperature superconductors (HTS). Additional tests of the prototype cable are planned in the coming weeks with the purpose of conducting further measurements and experimenting under various conditions. In parallel to these experimental activities, IASS has established contacts with partners from European industries and transmission operators in order to undertake the next steps in the R&D process and move towards industrial application.

Weitere Informationen:

http://www.iass-potsdam.de
http://www.iass-potsdam.de/research-clusters/earth-energy-and-environment-e3/sci...

Corina Weber | idw - Informationsdienst Wissenschaft

Further reports about: CERN HVDC IASS Sustainability capacity construction diameter materials temperatures underground

More articles from Physics and Astronomy:

nachricht A New Litmus Test for Chaos?
29.07.2015 | American Institute of Physics (AIP)

nachricht First detection of lithium from an exploding star
29.07.2015 | ESO

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Superfast fluorescence sets new speed record

Plasmonic device has speed and efficiency to serve optical computers

Researchers have developed an ultrafast light-emitting device that can flip on and off 90 billion times a second and could form the basis of optical computing.

Im Focus: Unlocking the rice immune system

Joint BioEnergy Institute study identifies bacterial protein that is key to protecting rice against bacterial blight

A bacterial signal that when recognized by rice plants enables the plants to resist a devastating blight disease has been identified by a multi-national team...

Im Focus: Smarter window materials can control light and energy

Researchers in the Cockrell School of Engineering at The University of Texas at Austin are one step closer to delivering smart windows with a new level of energy efficiency, engineering materials that allow windows to reveal light without transferring heat and, conversely, to block light while allowing heat transmission, as described in two new research papers.

By allowing indoor occupants to more precisely control the energy and sunlight passing through a window, the new materials could significantly reduce costs for...

Im Focus: Simulations lead to design of near-frictionless material

Argonne scientists used Mira to identify and improve a new mechanism for eliminating friction, which fed into the development of a hybrid material that exhibited superlubricity at the macroscale for the first time. Argonne Leadership Computing Facility (ALCF) researchers helped enable the groundbreaking simulations by overcoming a performance bottleneck that doubled the speed of the team's code.

While reviewing the simulation results of a promising new lubricant material, Argonne researcher Sanket Deshmukh stumbled upon a phenomenon that had never been...

Im Focus: NASA satellite camera provides 'EPIC' view of Earth

A NASA camera on the Deep Space Climate Observatory (DSCOVR) satellite has returned its first view of the entire sunlit side of Earth from one million miles away.

The color images of Earth from NASA's Earth Polychromatic Imaging Camera (EPIC) are generated by combining three separate images to create a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Euro Bio-inspired - International Conference and Exhibition on Bio-inspired Materials

23.07.2015 | Event News

Clash of Realities – International Conference on the Art, Technology and Theory of Digital Games

10.07.2015 | Event News

World Conference on Regenerative Medicine in Leipzig: Last chance to submit abstracts until 2 July

25.06.2015 | Event News

 
Latest News

A New Litmus Test for Chaos?

29.07.2015 | Physics and Astronomy

New Computer Model Could Explain how Simple Molecules Took First Step Toward Life

29.07.2015 | Life Sciences

New ERC calls published under Horizon 2020

29.07.2015 | Awards Funding

VideoLinks
B2B-VideoLinks
More VideoLinks >>>