Optimal Utilization of the Hydropower System

1.        Introductionresearch in the PhD-project will be to improve this
Today power system has import in normal inflowprocess in means of models and especially the
years, and without the reduction in consumption seen inconnection between them.
2002-2003 the energy deficit in the 2003 would haveFig. 2. Decomposing the planning process
been hard to neglect. The expected future growth ofDescribing the overall process is important and a
the consumption together with reluctance to usage thepublication focusing on methods on different levels and
remaining hydropower resources shifts the balancehow to connect them is under writing. Establishing a
even further. The criterion for the thesis is to contributebetter model for connecting the long- and
to an efficient usage of the hydropower system inmedium-term strategic planning with short-term
compliance with other natural energy resources inscheduling is the main focus on the practical work
Norway. The overall picture is illustrated in fig. 1, this iscarried out at the moment. This could also be called
the framework for utilizing hydro power in Norway.refitting the strategy. The main challenge is that the
Fig 1. Optimal usage of hydropowernumber of details, it is possible to include in stochastic
2.      Outer ringmodels on the long-term or medium-term level, is lower,
Most elements in the outer ring impact on thethat the number of details that must be included in
conditions for optimal utilization of the hydropoweroperational models. This may result in errors when
resources. In the research the resource inflow will beimplementing the long-term strategy. Such errors are
considered exogenous given but impact from anot only bad for the companies but may also impact
changing climate is briefly covered in [1]. So far theon the overall success of maintaining the energy
climate change goes in favor of hydro power. Not onlybalance in the system.
will the inflow in important hydro power areas increase,How to implement the short-term decisions in the
the inflow will also a change in distribution over themarket is described in [2] and [3]. Various techniques
year that reduces spillage. Energy policy is consideredhave been developed over the years for modelling
an externality except when it comes to environment.short-term scheduling in thermal as well as
Environment for hydropower usage is dependent onhydropower dominated systems. An overview of
both national and international trends. Global emission isthese methods and their implications regarding
debated and the value of hydropower can beapplication for hydropower is described in [5]. The area
expected to increase [6]. Local impact fromof short-term scheduling for hydro power is becoming
hydropower may be discussed in terms of how tomore focused in the power companies. This increases
minimize these impacts this could somehow bethe need for decision support for special topologies as
included in the research. Combined action withdescribed in [4].
neighboring systems will be important for security ofReferences
the energy supply in the hydropower system and may[1] M.M. Belsnes, A. Haakestad and L. Tøfte,
lead to synergy effects on money flow and”Impact from climate change on regulated
environment as well.watercourses”,
3.      Market & RulesHydropower’05, Stavanger, May 2005.
Then the market ring is a task by itself. In this project[2] O.B. Fosso and M.M. Belsnes, “Short-term Hydro
“Market&Rules” is provider of premises forScheduling in a Liberalized Power System”,
the planning processes that decides whetherPowerCon 2004, Singapore, Nov. 2004
hydropower can be optimally utilized or not. At least at[3] M. M. Belsnes, I. Honve, SINTEF Energy Research
this point the market, the set rules and otherProf. O. B. Fosso, Norwegian University of Science and
constraints are considered externally given. TheTechnology “Bidding in the secondary reserve
modeling of market and market imperfections ismarket from a hydropower perspective”, PSCC
important to understand and model in order to2005, Liege, Aug.2005.
investigate the current market situation. An exam work[4] M.M. Belsnes, J. Røynstrand and O.B. Fosso,
for a course in market power at NHH showed that“Handling State Dependent Nonlinear Tunnel Flows
even a small imperfection may lead to a large shift inin Short-term Hydropower Scheduling”,
benefit between supply and demand. A publicationPOWERCON 2004, Singapore.
describing market models and market modeling is[5] M.M. Belsnes, T. Gjengedal and O.B. Fosso,
under construction together with Post. Doc. Geir“Methods for Short-term Generation Scheduling in
Warland. How to implement the short-term decisions inHydro Power Dominated Power Systems”,
the market is described in [2] and [3].Hydropower’05, Stavanger, May 2005.
4.      Planning process[6] Michael M. Belsnes, Arne Haugstad, Birger Mo and
From an operation research perspective the planningPeter Markussen ”Quota Modelling in Hydrothermal
processes are complex and for practical purposes itSystems” PowerTech 2003, Bologna, June 2003.
also needs to be decomposed. The main focus of the