Powering Europe - European Wind Energy Association

ImmeDIateOppOrtUNItIeSfOrUpgraDe:
OptImalUSeOftheNetWOrk
In the short term, and at relatively low levels of wind
power penetration, transmission upgrades often coincide
with methods of congestion management and
optimisation in the transmission system. Moreover,
there exist technical measures which do not involve
excessive expenditure, but instead avoid or postpone
network investments. A number of attractive technologies
exist that have significant potentials for accelerating
grid capacity and easing wind energy integration
are discussed here.
Dynamiclineratingwithtemperaturemonitoring
Dynamic line rating allows existing power lines to be
used in a more optimal way by operating them at higher
capacities by monitoring the temperature. Transmission
capacity increases with the cooling effect of
certain weather conditions, such as the wind blowing.
The amount of power produced by wind power plants
is obviously higher when it is windy. Hence, the use of
dynamic line rating with temperature monitoring would
ease the transmission constraints associated with a
large wind power output. The amount of wind power
produced also tends to be higher at night and during
cooler periods of the year, so again dynamic line rating
would allow more transmission capacity to be used.
This approach is already in use in a few places, and industrial
solutions are available 1 . The standardisation
of this method is ongoing. A study for Germany [Burges,
2006] has quantified the possibilities for dynamic
line rating, and found significant opportunities depending
on the regional climate and wind conditions.
1 It is relevant to consider this solution also for the more general case with more renewables in the grid. Then it is found that solar
power output tends to be higher during hotter times of day, when transmission capability is lower. Still, it is likely that dynamic line
ratings would benefit solar too, since most of the time transmission lines limits are likely too conservative.
chApTEr 4 Upgradingelectricitynetworks–challengesandsolutions
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