Transmission
Energy Challenges Worldwide
Just the
FACTS
Flexible AC Transmission Systems (FACTS) help to regulate voltage
and reduce transmission losses. Based on transcripts of phone calls to
eight utilities around the world, our author reports on how FACTS
meet their local and systemic requirements.
Text: Chris Kraul Illustration: Lizzie Roberts
I
n Brazil, the challenge for the
electric power company is to
­insure stable transmission of
power over high-voltage lines spanning far-flung geographical extremes.
In environmentally attuned Denmark,
it’s to integrate the irregular pulse of
offshore wind energy seamlessly with
the central grid. Halfway around the
world in Australia, the task is simply
to ensure system stability by compensating voltage drops.
As never before, electric power companies worldwide are straining to meet
several imperatives: satisfy growing
energy demand, deliver remote sources of alternative power to sustainability-minded consumers, and – in an
age of public concern over carbon footprints and greenhouse gases – waste
as little electric energy as possible in
its transmission.
These market and policy goals often
lead power companies around the
world to the same solution: Flexible
AC Transmission Systems – or FACTS
– to assure grid stability and consistency. The Siemens product portfolio
includes parallel compensation systems, such as SVC and SVC PLUS, which
regulate voltages in networks with
­extreme use fluctuations, and series
compensation systems, which increase
the transmission capability of longdistance power lines.
Although the basic concepts of FACTS
are decades old, Siemens’ advances
in system software and technical
hardware have made them essential
tools for power utilities striving for
maximum grid performance.
Parallel compensation FACTS aim at
regulating voltage at times of extreme
fluctuations in demand, as in industrial zones in Brazil or during the summer months in Saudi Arabia, when a
near-universal need for air-conditioning stresses the grid and causes the
network voltage to dip. With cuttingedge thyristor-based technology installed at load centers or substations,
the systems’ capacitor cans and reactor coils provide or take out reactive
power, reducing the risk of system
failure.
Series compensation FACTS help power
companies increase power transfer
capability in overhead lines by electrically shortening their length, thereby
reducing the resistance and thus the
power losses, an operational dilemma
in any power transmission network.
Increasingly, power companies turn to
series compensation FACTS as an economic alternative to putting up new
lines or substations.
The systems accomplish improved
power transfer with capacitor banks
that are protected by metal oxide varistors (MOVs) to guard against lightning or surges that might otherwise
cause them to fail.
A distinct advantage of FACTS is the
flexibility of application – as confirmed
by the responses of executives from
eight electric power companies around
the world, all Siemens customers, but
each with a different set of operating
challenges and goals. In the following
article, all eight graciously answer
the same three questions: Why they
needed the FACTS solution, the positive ­results they have experienced
since installation of the system, and
why they chose the Siemens product
over other options. Here is what they
told us.
Living Energy · No. 7 | November 2012 63
Transmission
Transmission
Jesper Hjulmand,
Lake Singh, Major Projects Manager, Hydro One, Canada
Managing Director,
SEAS-NVE, Denmark
Denmark has set a national goal
of eliminating all fossil-fuelburning electric power plants
by 2050. That ambitious target
has presented power company
SEAS-NVE, the country’s largest
consumer-owned utility, with
an enormous challenge, namely
how to integrate innovative
sources of renewable energy
into the r­ egion’s power capacity,
while assuring customers of stable and reliable electric power.
To meet the first part of the challenge, SEAS-NVE is shifting to
an increasing reliance on wind
power generated in the Baltic Sea,
including the 160-megawatt
Nysted and Rodsand wind farms
located offshore near the island
of Lolland. The 162 wind turbines there generate enough
power at peak performance to
light 300,000 households. The
second part of the challenge –
keeping the grid stable as more
wind power is brought online –
was more complicated, the utility’s Managing Director Jesper
Hjulmand explains. The traditional solution would have been
to build a power plant in the
southern area of coverage to
balance reactive power when
the wind turbines are still.
But working with Siemens engineers, the utility settled on a
much more cost-effective FACTS
solution: a SVC parallel compensation system to provide reactive power and voltage stability.
The system also successfully
met a third challenge: It was built
indoors in a village with strict
noise restrictions. “In terms of
technology and price, it was the
best solution,” says Hjulmand.
And as for stabilizing the always
fluctuating supply of wind
­power? “Several times, the SVC
has helped us avoid blackouts
from big leaps in voltage.”
64 Living Energy · No. 7 | November 2012
For Hydro One, an electric power transmission company based in Toronto, the challenge was clear: How to insure voltage support during the decommissioning of
one of the region’s largest generation stations, the highly pollutive 2,000-megawatt
coal-burning power plant in Nanticoke in southwestern Ontario. To reduce its carbon footprint, power generator Ontario Power Authority will replace it by 2014 with
wind, added nuclear and natural-gas-fueled generation.
Assuming load remains the same, the loss of that much capacity posed a high risk
of serious voltage loss and possible system failure and blackout, says Hydro One’s
Major Projects Manager Lake Singh. The “on-and-off” nature of wind generation
that is coming online to replace it also will cause voltage to fluctuate. Moreover,
the power that will replace Nanticoke will come from as far as 200 miles away, presenting further risks of higher resistance and lessened transmission capacity.
The solution Hydro One chose was to install a Siemens SVC right on the Nanticoke
power plant site to provide voltage support during “contingency conditions” as
the big generation station was phased out. Why Siemens? Economics were decisive,
but even more so were studies that Singh’s team carried out that showed the company’s SVC technology generated no “harmonics,” or distorted sine waves i­ nside
the voltage that can cause power loss and damage to equipment.
“This is the backbone of our transmission grid, and as a transmitter we have to
keep it as clean as electrically possible,” says Singh. “Siemens technology offered
us the cleanest technical solution.”
Roberto Farina, Technical Manager,
Ahmed Al-Mubarak, Manager of
Administración Nacional de Electricidad, Paraguay
Strategic Planning, Saudi Electric C
­ ompany, Saudi Arabia
As in many emerging countries, power supply
problems faced by Paraguay’s main electric utility,
Administración Nacional de Electricidad, or ANDE,
flow directly from rapidly rising demand. In Paraguay’s case, load has grown at a staggering 9 percent annual rate in recent years, according to the
utility’s Technical Manager Roberto Farina. Driving
the demand growth is industrial expansion, but
also increases in Paraguayans’ per capita income
and consumption as a result of the global commodities boom.
Much of ANDE’s demand growth is occurring in
and around Pedro Juan Caballero, a northern city on the Brazilian border
that has seen a great increase in industrial and commercial activity. Rising
peaks in power consumption, particularly during the work week, have
­created voltage level problems for the entire grid.
Although 99 percent of Paraguay’s electricity is hydro, ANDE was facing
the necessity of building a fossil-fuel-powered generation plant to balance
the wild swings in voltage levels in the north. That is, until Farina and his
technical staff did a cost-benefit analysis of a FACTS alternative. Hands
down, the option of a Siemens SVC system at the Horqueta transformer
station proved a more economic alternative. As a bonus to the balancing by
the SVC, Farina figures an active power of 40 megawatts could additionally be transmitted to the northern grid once fully installed this August.
“In a technical and an economic aspect, Siemens met the criteria and made
the lowest bid,” Farina says. “We have great hopes that the FACTS will
solve our voltage issues – and help us keep up with demand.”
Insuring grid stability and voltage support are routine tasks for managers of most power companies around the world. For Saudi Electric
Company (SEC), which faces mind-boggling extremes in climate, geography and load fluctuations, they can be Herculean challenges.
Saudi Arabia’s principal power company must transmit electricity over
immense distances that separate cities and oil installations, and that
requires long transmission lines. Rising oil prices have generated increased industrial activity, particularly in energy-intensive petrochemicals. But it is the explosion of residential and commercial air-conditioning use that has caused perhaps the biggest threat of voltage
collapse and blackouts.
According to Ahmed Al-Mubarak, Manager of SEC’s strategic planning
department, system-wide load during scorching summer months
goes as high as 50,000 megawatts, or two-thirds more than the
30,000-megawatt load during winter, when AC is not necessary. More
than 80 percent of summer demand is to power air-conditioning units.
Somehow, the company must balance out the system, during those
­extreme load swings.
To accomplish that, Saudi Electric is in the process of installing its
fourth Siemens FACTS in the country’s central region. The most visible
evidence of beneficial effects is in the city of Jeddah on the Red Sea
where, prior to the installation of the first SVC system in 2006, the city
was regularly victimized by blackouts. Now, system failures simply
“don’t happen,” says Al-Mubarak.
Living Energy · No. 7 | November 2012 65
Transmission
Transmission
Simon Bartlett, Chief Operating Officer,
Powerlink Queensland, Australia
The decade-long global boom in coal, a commodity that is mined
right in its own backyard in the mineral-rich Bowen Basin, has
been a huge business stimulus for Powerlink Queensland, an
­electric transmission utility in eastern Australia. Electricity is
needed not only to extract the coal, but also to transport it to eastern ports via electric-powered trains of the QR National Railroad.
But the 10 percent annual increases in coal exports of late have
also presented the transmission company with an unprecedented
system stability challenge. Simon Bartlett, Powerlink’s Chief
­Operating Officer, likens the loss of voltage in the transmission
system during heavy electric train traffic to the loss of water pressure when everyone is out watering their yards. “It’s even more
complicated with energy. If you don’t do something to compensate
for the drop in voltage, you risk system failure and blackouts,”
Bartlett says.
To deal with added strain, Powerlink considered extending its
high-capacity grid all the way out to mining areas located some
250 kilometers inland from Brisbane, the provincial capital and
population center. Instead, after a competitive tender, the company
is installing nine Siemens SVC parallel compensation devices at strategic locations on the grid.
The upshot for the railroad is that it can mothball some diesel-power locomotives it has
been using provisionally and complete its conversion to “green” all-electric rail transport.
For Powerlink, the SVCs mean more reliable service. “They enable us to manage phase
­balancing in a more cost-effective way,” Bartlett says.
Stuart MacDonald,
Power System Analysis Manager, Transpower, New Zealand
Transpower, operator of New Zealand’s long and slender electric transmission network, delivers power to a highly dispersed population
spread out across 1,000 miles of natural obstacles including mountains,
forests, steep valleys and the Cook Strait, which separates the country’s
two principal islands. Added to the geographical realities is seismic
­activity, which most recently made headlines when the December 2010
earthquake devastated Christchurch, the country’s second-largest city.
A few years ago, when Transpower’s relatively long transmission lines,
which connect major loads to generation centers, began to reach their
thermal limits, the company began looking for ways of maximizing
its existing assets – reliably increasing power transfer without having
to invest in new transmission lines.
The company ultimately decided to buy a STATCOM, or package of
­dynamic reactive devices, that included two Siemens SVC PLUS units
for the Kikiwa station at northern South Island. Transpower’s Stuart
MacDonald says the units have improved the security of service, especially to remoter parts of the island that in the past were prone to deteriorating voltage quality. The SVCs have also enabled the transmission company to defer building
new transmission circuits, saving customers money and avoiding damage to the environment.
Low cost and confidence in the Siemens brand were decisive factors in Transpower’s bid award.
“It is a large engineering company with deep technical resources and capabilities, and long
project delivery experience, which gave us confidence under a tight schedule,” says MacDonald.
66 Living Energy · No. 7 | November 2012
Nicholas Lizanich,
Senior Vice President for
Operations, Long Island
Power Authority, USA
Long Island Power Authority (LIPA),
the municipal utility that serves New
York’s Long Island and part of Queens,
is in the enviable position of owning
transmission infrastructure so efficient
that it’s more economic to import the
bulk of its power than to generate electricity itself.
Still, the eastern half of the 120-mileslong island is vulnerable to voltage
faults, mainly because transmission
­interties are all situated from the middle to the west end of the island. That
means the utility must maintain, on
a contingency basis, several inefficient
and highly polluting oil-burning power
plants on the eastern half as reactive
sources to keep voltage balanced, particularly during warm-weather air-conditioning season.
“As you get closer to the east end of
the island, you don’t have [power source]
redundancies, so any fault causes a
pretty considerable voltage dip – and
that can get you to voltage collapse if
you don’t have the devices out there
to absorb the impact of the fault,” says
Nicholas Lizanich, Senior Vice President for Operations.
Recently, LIPA bought two new Siemens
SVC PLUS systems that Lizanich hopes
will mean the utility will never again
have to use the inefficient generators.
The units also include high-speed, thyristor-switched capacitors that allow
rapid turning on and off of reactive VARs,
a component that helps bring additional strength to the grid.
“We evaluated Siemens on cost and technology solution, and it filled the need.
I also liked the idea that the system was
relatively small,” Lizanich says. “I could
fit it on the real estate we had.”
A former foreign correspondent for the
Los Angeles Times, Chris Kraul is a freelance
science, technology and business writer
based in Bogotá, Colombia.
Christian Mendes,
Project Manager, Isolux Corsan, Brazil
Manaus and Macapá are two fast-growing Brazilian cities situated on
the Amazon River that on a map may look isolated. But both, especially
Manaus, are up-and-coming industrial and agribusiness centers with
expanding populations and thus increased demand for electric power.
Each is highly dependent on a 1980s-era hydropower project – the massive 8,370-megawatt Tucurui complex in Para state that is connected
to both cities by transmission lines operated by Isolux Corsan.
The operational challenge lies in the 800 miles of distance that separate Tucurui from Manaus, the 500 miles from the dam to Macapá, and
the increased transmission line resistance over such long cables that,
unless compensated for, causes power loss.
In a new initiative to insure system stability, Isolux Corsan has bought
several Siemens series compensations systems: 3 SVC units and 10 FSC
systems to be installed by year-end at various substations along the grid.
Isolux Project Manager Christian Mendes describes the Siemens FACTS
as “essential in increasing power system stability and transmission capacity – most likely, these lines
would not be feasible without FACTS
devices.”
Asked to explain why Isolux chose
Siemens products over the competition, Mendes says Siemens submitted the lowest bid, possibly because
it produces the capacitor units at a
factory near São Paulo. The company’s strong local service staff, as well
as its technology center located in
Brazil, made Isolux confident that
Siemens would provide a good aftersales response, reports Mendes.
Living Energy · No. 7 | November 2012 67