ABB Hails ‘Supergrids’ Breakthrough

November 7, 2012

By Michael Kavanagh

ABB, the Swiss engineering conglomerate, hailed a major breakthrough in power transmission technology that it says will allow for the wider exploitation of renewable energy.

A lack of heavy-duty circuit breakers capable of safely handling the extreme voltage levels required for direct current (DC) transmission over long distances has been a key obstacle for schemes designed to harvest power generated by offshore wind farms, remote hydroelectric plants and desert-based solar projects.

Joe Hogan, chief executive of ABB, said that the development of its circuit breakers would finally allow for long-distance DC output to be easily integrated into existing local and national power grids, which are based on the more robust alternating current (AC) system.

“This historical breakthrough will make it possible to build the grid of the future. Overlay DC grids will be able to interconnect countries and continents, balance loads and reinforce the existing AC transmission networks.”

Brice Koch, head of power systems at ABB, said that solving the puzzle was equivalent to “bringing a speeding 40-tonne truck to a halt within five milliseconds”.

Many of Europe’s offshore wind farms already transmit energy to shore using so-called high voltage direct current (HVDC). But the problems of integrating HVDC output into local AC grids has held back operators’ ability efficiently to pool and distribute the output of remotely produced wind power.

HVDC transmission can be 50 per cent more efficient at preserving energy over long distances compared with conventional AC-based systems, but the propensity of DC transmission to bring down entire grid systems through localised disruptions has thwarted attempts to roll out parallel grids using the energy-saving technology.

But Simon Cowdroy, who has advised the UK government and European Commission on the potential of so-called DC “supergrids”, said that the breakthrough by ABB could bring such subsea and cross-border transmission schemes a step closer.

He suggested that ABB may have stolen a march on other suppliers including Siemens and Alstom, which have also been investing in the development of high-voltage DC technology.

Mr Cowdroy, head of grid services at WSP Future Energy, said that the development of heavy-duty breakers was “a key component in getting towards a supergrid”.

He added that the development of an integrated network across the North Sea could allow the integration of output from hydro and wind power assets across Norway and Sweden into UK and continental energy markets.

Other bodies, such as Friends of the Supergrid, advocate the creation of a parallel DC-based system that would be the “transmission backbone of Europe’s decarbonised power sector”. It also advocates its extension across north Africa to harvest solar power for use in Europe under the Desertec initiative.

Former UK energy minister Charles Hendry also launched talks with Iceland’s ambassador earlier this year to consider the potential of importing geothermal electricity derived from Iceland active volcanic system to the UK using HVDC transmission.

Copyright The Financial Times Limited 2012.