Siemens 2007 Annual Report Download - page 61

Energy 61
HVDC undersea cable. Siemens converter stations
transform alternating current into direct current at
the New Jersey end and then reconvert it into alter-
nating current when it reaches Long Island. The
system’s advantages: fewer CO2 emissions – since
the power from the mainland comes in part from
CO2-free generation – and fewer power plants on
the densely populated island.
But Asia and the U.S. are not the only places where
our HVDC transmission technology has scored ma-
jor successes. It’s also been extremely well received
in Europe, where we’ve landed three orders for
HVDC systems in the last six months alone. Most
recently, in September 2007, we signed a contract
with Spanish network operator Red Eléctrica de
España to link the island of Majorca with the main-
land power grid via a 400-MW 250-kV HVDC under-
sea cable stretching 250 kilometers. The largest of
the Balearic Islands, Majorca has a permanent pop-
ulation of some 790,000 people. In addition, up to
seven million vacationers fl ock to the island every
year. Thanks to the new HVDC link, power demands
during the peak holiday season can now be met by
electricity imports from the European continent.
We’ve also received orders to supply converters for
the 600-MW 400-kV Storebaelt undersea link, which
will run between the Danish islands of Funen and
Zealand, and for the 1,000-MW 450-kV BritNed un-
dersea link, which will connect the Netherlands and
Great Britain.
HVDC Plus is what we call our latest innovation in
high-voltage direct-current technology. The advan-
tages of the new system, which employs voltage-
sourced converters, include the compact dimen-
sions of the converter stations used and the
system’s ability to link large power grids to weak
power systems. Our HDVC Plus solution will open
up new opportunities for low-loss power transmis-
sion – for instance, from offshore wind farms to the
mainland, from the mainland to offshore oil plat-
forms, and from remote power plants to large
urban areas. The solution is being implemented
for the fi rst time in California, where it will signifi -
cantly increase the security and reliability of San
Francisco’s power supply network.