Environmental Engineering Reference
In-Depth Information
range of IT technology has barely affected the electricity networks. Interestingly, the long
delayed revolution required will be precipitated by the imminent impact of renewable sources.
The distributed and variable nature of renewables will require intelligently controlled power
electronic hardware to maintain power quality and optimize energy fl ows. This required
revolution in fl exibility and controllability of the network will, of course, be of immense
benefi t to traditional generation as well. Much of the distribution network in most
countries is at least 40 years old and will have to be replaced over the next decade. There is
therefore a great opportunity to introduce innovative technologies rather than replace like
with like.
Traditionally, power systems have been run on the policy that whenever the consumer
demands energy this should be instantly satisfi ed from dispatchable generation. With increas-
ing proportions of renewable generation this philosophy must be changed but without sub-
stantial inconvenience to the consumer. Demand-side fl exibility will require that consumers
adjust their demand profi le to meet supply through deferrable loads. This will require intelli-
gent control and could be done through time-of-use tariffs requiring customer voluntary
response, to hard wired direct control and everything in between. If demand can shift time-
wise to suit generation, the availability of primary energy will be dictating the pattern of
consumption rather than the opposite. In such a power system 'base load' electricity may not
continue to have the signifi cance it has at present.
An active distribution network is by defi nition more complex than the current system,
and building and managing it will require new skills. In this future power system,
renewable generation will be injected and active control will be implemented at all system
levels.
To conclude, a fundamental rethink will be needed of the way electricity is generated,
transmitted and distributed in the power systems of the future. Variable generation infeeds
coupled with bidirectional network fl ows will become commonplace. This rethink does not
only require the adoption of new technologies but also a change in the mindset or 'culture'
of power system engineers. This topic has endeavoured to cover the basic principles of how
power systems will evolve from the present time when renewable energy contributes a minute
proportion towards electricity production to a future when this proportion becomes
substantial.
References
[1] A readable overview of HVDC technology can be found in the ABB site www.abb.com/hvdc .
[2] Jacobson , B. et al. ' HVDC with voltage source converters and extruded cables for up to ± 300 kV and
1000 MW ' , CIGRE Paper B4 - 105, 2006.
[3] O ' Connor , E. ' European unity, a vision for sustainable power in Europe ' ,
Renewable Energy World
, March -
April 2006 , 124 - 127 .
[4] Danish Wind Energy Association website www.windpower.org .
[5] Gagnon , L. , Berlanger , C. and Uchiyama , Y. ' Life - cycle assessment of electricity generation options ' ,
Energy
Policy
, 2002 , 30 , 14 .
[6] van Sark , W.G.J.H.M. , Brandsen , G.W. , Fleuster , M. and Hekkert , M.P. ' Analysis of the silicon market: will
thin fi lms profi t? '
Energy Policy
, June 2007 , 35 ( 6 ), 3121 - 3125 .
[7] 'Decentralising power: an energy revolution for the 21st century', Greenpeace Publication, 2006.
[8] 'Planning of the grid integration of wind energy in Germany onshore and offshore up to 2020', DENA Study,
2005.
