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World Potential (SWEDEN)
Electricity Supply Network
When electrification of the country began at the end of the
nineteenth century,the power was produced in small hydroelectric
stations and distributed on local networks. The first high
voltage line for alternating current was put into operation
in 1893. The networks were gradually interconnected to regional
networks and the transmission voltages became higher and higher.
More and more remote waterfalls were harnessed. At the end
of the 1940's water power development reached the river Lule
Alv. Power from this and from other rivers in the North was
considerable. However, it had to be transferred about 1000
km. If 220 kV, the highest voltage in Sweden until then, was
to be used, roughly 30 lines would ultimately be needed. It
was obvious that a system with a higher capacity per line
would have to be developed. Vattenfall AB and ASEA studied
various higher voltages. The result of these studies showed
that 400 kV was the best choice from both an economic and
a technical point of view. The first line for this voltage
in the world, the 1000 km long line between HarsprAnget and
HalIsberg, was put into operation in 1952.
Today the 400 kV network contains eight North South lines
and has total length of roughly 10,500 km.The 220 kV network
has a total length of roughly 4,400 km.The main function of
the trunk line system, 400 and 220 kV, is still to transfer
power from the hydropower area in the North to the consumption
area in the South. The number of substations has increased
at the same time, and large nuclear power stations have been
built in the South, so the 400 kV system has partly acquired
the character of a backbone network.
From the substations of the trunk line, system power is distributed
in several voltage steps to the consumers. The most common
voltages in the distribution networks are 132, 7 7, 45, 22
and 11 kV. In one and the same region only two or three of
these voltage steps are used. The final power supply to the
normal subscriber is made with a 4001230 V (50 Hz) connection.
Practically all households in Sweden now have access to electric
power.
In towns and urban areas retail distribution is often handled
by municipalities. In country districts the suppliers generally
are electric power companies, distribution associations or
municipalities. There are about 250 distribution units. The
figure has decreased rapidly as a result of rationalization
and mergers.
Country Brief
History of Hydropower
Installed Capacity
Electricity Supply
Network
Planning, Operation,
and Power Exchange
The Deregulated
Electricity Market
Hydrology and Topography
Background of Hydro
Development
Hydropower Developed
Until 1995
Available Hydropower
Potential
The Possibilities
of Further Development
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