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Day-ahead modelling of the electricity balancing market : A study of linear machine learning models used for modelling predictions of mFRR volumesBankefors, John January 2024 (has links)
The study aimed to define and investigate relevant parameters affecting manual frequency restoration reserve (mFRR) volumes of the balancing market in the Finnish price area. It also aimed to find suitable models and investigate Day-ahead prediction possibilities of mFRR volumes. Parameters related to mFRR volumes Day-ahead predictions were identified in several earlier studies where of nine parameters were investigated. The correlations between mFRR volumes and the different parameters were investigated using Spearman’s correlation. Different linear machine learning models for Day-ahead predictions of mFRR volumes were builtand tested in Python. The resulting models used for predicting mFRR volumes in Python were one ARIMAX model and one SARIMAX model. The models were validated with a walk-forward method where Day-ahead predictions were conducted monthly for one year. The accuracy of the predictions was measured by the validation parameters Mean Absolute Value, Root Mean Square Error and Median Absolute Deviation. Results from the study show that it is difficult to predict absolute activated mFRR volumes. Although, it might be possible to predict that mFRR volumes will be activated or not, up- or down regulated to some extent. One explanation of the difficulties in predicting mFRR volumes is dueto mFRR being a balancing product whose function is to regulate disturbances in the electricity grid.
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Inclusion of Wind Turbines into Frequency Support Services : Exploring frequency stability issues and comparing regulation power market productsAndersson, Oskar January 2021 (has links)
There is a trend in Sweden towards increasing the electricity production from renewable energy sources in the electric grid. The increased share of renewables could be seen as essential for Sweden to be able to meet the obligated climate goals. Integration of renewables will enable Sweden to be a progressive part in reducing greenhouse gases and decreasing the global warming. However, one issue with renewable energy sources is the inverter governed production. This, together with the decommission of larger synchronous generators, results in decreasing the inertia and increasing the instability inthe grid. This thesis is dedicated to elaborating on frequency stability issues and investigating how Variable Speed Wind Turbines (VSWT) could contribute towards stabilized operation when included in frequency support services. The study is generated through an extensive research process where focus areas are identified. Questions are purposed and then discussed through interviews with experienced people in the field. Estimated power production series from a wind turbine park (WTP) are applied in a constructed model to study the possibilities appearing when including VSWTs in frequency support services. The income generated from including VSWTs in different regulation power market services is with the model compared against solely procuring the production capacity on the day ahead market. The studied frequency support services are then compared altogether to generate favorable solutions. The study examines both economic as well as technical features of the inclusion of VSWTs in frequency support services. Results found in the study were that inclusion of wind turbines for power regulation purposes could be seen as increasingly manageable and needed in the electric grid. The maturity of technical solutions alongwith a transition in the regulation power market could be observed as leading factors. The diversification of regulation abilities and the increasing economic incentives in the regulation power market was also found to be important reasons for including wind turbines in the regulation power market. In the study, it was also found thataggregating the power production from several VSWT could increase the ability to deliver the studied services. It was concluded that inclusion of VSWT in the frequency containment reserve during disturbed operation for down-regulation purposes as well as the fast frequency reserve was the most promising frequency support products for the inclusion of wind turbines. When including battery energy storages and to a larger part managing the durability demands for the services then the frequency contain reserve for normal operation and the frequency containment reserve for disturbed operation for upregulation purposes could be observed as preferable alternatives. Regulation abilities were concluded as achievable with the use of pitch and torque regulation techniques available in the variable speed wind turbine.
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Frekvensreglering från batterilager i flerbostadshus : En studie av lönsamheten hos batteristyrd mFRR-reglering / Utilizing battery storages in multifamily residentials to profit from frequency regulation on the market mFRRHolm, Ludvig, Mattiasson, Per January 2021 (has links)
Elnätet är ett komplext och viktigt system som konstruerats som en av de mest imponerande bedrifterna under ingenjörskonstens moderna tid. Det överför elektrisk energi till otaliga byggnader, industrier, skolor och hem. Och alltsammans sker konstant, varje minut av varje dag, året runt. Grundbulten i systemet är den att en ständig balans måste råda mellan produktion och förbrukning av elektricitet. Vid obalans riskerar nämligen strömavbrott och andra oönskade företeelser att inträffa. Huruvida produktion och förbrukning av elektricitet är i nivå kan beskrivas av elnätets frekvens. Genom att övervaka elnätsfrekvensens beteende fås en överskådlig bild av elnätets status i realtid samtidigt som stödtjänster kan implementeras proaktivt för att motverka eventuella störningar. Tidigare har dessa stödtjänster främst representerats av stora aktörer såsom vattenkraftsanläggningar med enorma förutsättningar för att agera som reglerkraft. I takt med en omställning till en alltmer förnybar energipalett ökar dock behovet av ny reglerkraft. Samtidigt syns ett accelererande av installering av batterilager i bostadsrättsföreningar som energieffektiviserar. Eventuellt finns här en outforskad potential. Möjligen kan batterilager i flerbostadshus utnyttjas för frekvensreglering som en ytterligare balanskraft för elnätet. Projektarbetet syftade till att utreda potentialen kring batteristyrd mFRR-reglering från flerbostadshus. För att utvärdera den eventuella lönsamheten modellerades batteristyrningen i MATLAB. Modellen baserades främst på historiska data för upp- och nedregleringsbud från Nord Pool. I och med kravet på 1 MWh som minsta budstorlek på marknaden gjordes antagandet att vid varje regleringstillfälle reglerar batterilagret i aggregation med andra batterilager som tillsammans täcker den totala kapaciteten på 1 MWh. Modellen fungerar på så sätt att varje uppreglering föranleds av en uppladdning av batterilagret via antingen nedreglering eller spotpriser. Beroende på vilket alternativ som är mest lönsamt. Vidare gjordes antagandet att inga uppregleringsbud sker i två påföljande timmar. Studiens mest lönsamma resultat genererades då batterilagret modellerades för att anta ett uppregleringsbud per dygn med det extra villkoret att samtliga bud som understiger 300 SEK/MWh förkastas. Vid dessa kriterium erhölls ett positivt årligt resultat om 149 100 kr från 306 battericykler. Med endast frekvensreglering som användningsområde för batterilagret konkluderade dock studien att, det positiva resultatet till trots, ingen lönsamhet kunde uppnås. Investeringskostnaden är nämligen ännu för hög. Å andra sidan tyder teknologiska framsteg inom batterisektorn på en avtagande kostnadsutveckling. Vid år 2030 väntas nämligen priset för batterilager vara 225 USD/kWh, vilket skulle förbättra resultaten från denna rapport. / The electricity grid is a exceptionally sophisticated and crucial system which was created as one of the most impressive accomplishments in modern engineering. It transmits electrical energy to innumerable buildings, factories, schools and homes. And it can never stop. The system relies on the constant balance between generated and consumed electricity. Should an imbalance occur, it might give rise to power outages or failures in appliances on the grid. Whether or not generated and consumed electricity is at balance is determined by the grid frequency. By surveilling how the grid frequency behaves, an overview of the complete system can be obtained in real time. This is useful when it comes to deciding on whether or not to implement supporting mechanisms to counteract disturbances. The supporting mechanisms were historically represented by large facilities such as water power plants who possess great abilities of regulating the power balance on the grid. With the ongoing switch to renewables the need for more regulating power increases. At the same time installments of battery storage in energy efficient housing can be seen as accelerating. Here might be an untapped potential. What if battery storage in residential properties were utilized for frequency regulation as an additional balancing tool for the grid? The intent with this report was to outline the potential regarding power regulating via battery storages in multifamily residentials. In order to evaluate whether or not any profit could be redeemed, a battery control model was developed in MATLAB. The model was primarily based on historic data for regulating bids from Nord Pool. Since requirements on the market states that the lowest bid needs to be at least 1 MWh, the assumption was made that at every regulating occasion the battery regulates in aggregation with more batteries for a total capacity of 1 MWh. The objective of the model is to charge the battery using either spot price or down-regulating bids. Thereafter, an up-regulating bid is chosen. The assumption was made that no subsequent up-regulating bids were chosen. The most profitable optimization of the model was generated when 1 up-regulating bid was chosen per day with the additional condition that all bids under 300 SEK/MWh were rejected. At these criteria a yearly positive result of 149 100 kr was generated from 306 battery cycles. With frequency regulation as sole application for the battery storage, the study concluded that the model was not profitable. The cost of investment is yet too high. On the other hand, technological improvements will surely amount to declining prices. By year 2030 the price of battery storage may have fallen to 225 USD/kWh, which would improve the results in this study.
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