Pientuulivoimaloiden markkinapotentiaalin arviointi Suomessa ja globaalisti

Työn tavoitteena on selvittää pientuulivoimaloiden markkinapotentiaali Suomessa sekä muualla maailmassa, ja kartoittaa alalla toimivat kilpailijat. Tarkoituksena on myös arvioida kuinka tilanne tulee jatkossa kehittymään ja, mitkä ovat Hafmex Windforce Oy:n mahdollisuudet kilpailla kyseisillä markkinoilla. Lisäksi tarkastelun kohteena on selvittää millä edellytyksillä pientuulivoimaloita voidaan liittää paikalliseen sähkönjakeluverkkoon. Työssä on myös esitelty kaupallisten tuulivoimaloiden perusperiaatteita, sekä tällä hetkellä käytössä olevaa teknologiaa. Tarkemmin on keskitytty pientuulivoimaloiden toiminnan periaatteisiin. Työn teoriapohjassa tarkastellaan markkinatutkimuksen suorittamisen erityispiirteitä, markkinapotentiaalin määrittämiseen liittyviä käsitteitä ja kilpailija-analyysin suorittamista. Teoriaosa perustuu alan kirjallisuudesta, lehtiartikkeleista sekä internetistä kerättyyn materiaaliin.

Pientalon energiatehokkuuden vaatimusten kiristymisen vaikutus lämmitysratkaisujen hiilidioksidipäästöihin

Tässä työssä tarkastellaan pientalojen kiristyvien energiatehokkuusvaatimusten vaikutusta lämmitysratkaisuista aiheutuviin hiilidioksipäästöihin. Kiristyvät vaatimukset tähtäävät tarvittavan lämmitysenergian ja hiilidioksidipäästöjen pienenemiseen mutta ne vaikuttavat myös lämmitystapojen keskinäiseen kilpailukykyyn. Koska hiilidioksidipäästöt lämmitystapojen kesken ovat erilaisia, ei päästöt pienene samassa suhteessa lämmitysenergian pienentymisen kanssa mikäli järjestelmä vaihdetaan suurempipäästöiseen lämmitystapaan. Kannattavuuden perusteella arvioidaan mitkä lämmitystavat yleistyvät tulevaisuudessa ja kuinka muutos vaikuttaa hiilidioksipäästöihin. Tarkasteltavina lämmitysmuotoina on maalämpöpumppulämmitys, öljylämmitys ja kaukolämpölämmitys. Tarkasteltavia lämmitysmuotoja verrataan investointikustannuksiltaan edullisimpiin sähkölämmitysmuotoihin. Työssä todettiin energiatehokkuuden vaatimusten kiristämisen kasvattavan sähkölämmitystapojen osuutta. Koska lämmityssähkön hiilidioksidipäästöt ovat korkeat, joissain tapauksissa hiilidioksipäästöt jopa kasvavat energiatehokkuuden parantuessa.

Analysis of electricity distribution network operation business models and capitalization of control room functions with DMS

Electricity distribution network operation (NO) models are challenged as they are expected to continue to undergo changes during the coming decades in the fairly developed and regulated Nordic electricity market. Network asset managers are to adapt to competitive technoeconomical business models regarding the operation of increasingly intelligent distribution networks. Factors driving the changes for new business models within network operation include: increased investments in distributed automation (DA), regulative frameworks for annual profit limits and quality through outage cost, increasing end-customer demands, climatic changes and increasing use of data system tools, such as Distribution Management System (DMS). The doctoral thesis addresses the questions a) whether there exist conditions and qualifications for competitive markets within electricity distribution network operation and b) if so, identification of limitations and required business mechanisms. This doctoral thesis aims to provide an analytical business framework, primarily for electric utilities, for evaluation and development purposes of dedicated network operation models to meet future market dynamics within network operation. In the thesis, the generic build-up of a business model has been addressed through the use of the strategicbusiness hierarchy levels of mission, vision and strategy for definition of the strategic direction of the business followed by the planning, management and process execution levels of enterprisestrategy execution. Research questions within electricity distribution network operation are addressed at the specified hierarchy levels. The results of the research represent interdisciplinary findings in the areas of electrical engineering and production economics. The main scientific contributions include further development of the extended transaction cost economics (TCE) for government decisions within electricity networks and validation of the usability of the methodology for the electricity distribution industry. Moreover, DMS benefit evaluations in the thesis based on the outage cost calculations propose theoretical maximum benefits of DMS applications equalling roughly 25% of the annual outage costs and 10% of the respective operative costs in the case electric utility. Hence, the annual measurable theoretical benefits from the use of DMS applications are considerable. The theoretical results in the thesis are generally validated by surveys and questionnaires.

Auger-type granular fertylizer distributor: matemathical model and dynamic simulation

The objective of this study was to model mathematically and to simulate the dynamic behavior of an auger-type fertilizer applicator (AFA) in order to use the variable-rate application (VRA) and reduce the coefficient of variation (CV) of the application, proposing an angular speed controller θ' for the motor drive shaft. The input model was θ' and the response was the fertilizer mass flow, due to the construction, density of fertilizer, fill factor and the end position of the auger. The model was used to simulate a control system in open loop, with an electric drive for AFA using an armature voltage (V A) controller. By introducing a sinusoidal excitation signal in V A with amplitude and delay phase optimized and varying θ' during an operation cycle, it is obtained a reduction of 29.8% in the CV (constant V A) to 11.4%. The development of the mathematical model was a first step towards the introduction of electric drive systems and closed loop control for the implementation of AFA with low CV in VRA.

Sähköisen taloushallinnon vaikutukset tilitoimiston työskentelytapoihin Case-yrityksessä

Tämän tutkielman tavoitteena oli selvittää, mitä mahdollisuuksia ja haasteita sähköinen taloushallinto tuo tilitoimistoille ja miten ne vaikuttavat työskentelyyn. Vaikka sähköisiä taloushallinnon järjestelmiä on tutkittu paljon jo aiemmin, vielä ei kovin laajasti ole tarkasteltu sitä, miten ne käytännössä vaikuttavat tilitoimistoihin. Tutkielma on luonteeltaan kvalitatiivinen ja se on toteutettu case-tutkimuksena lappeenrantalaisesta tilitoimistosta. Tutkimuksen teoria rakentuu aihetta käsittelevän kirjallisuuden perusteella ja empiria on kerätty puolistrukturoiduilla teemahaastatteluilla. Haastatteluista saatuja tuloksia on verrattu kirjallisuudessa esitettyihin näkemyksiin sähköisen taloushallinnon mahdollisuuksista ja haasteista sekä sähköisen taloushallinnon vaikutuksista työskentelyyn. Tutkimuksessa selvisi, että kirjallisuudessa ja käytännössä sähköisen taloushallinnon tarjoamat mahdollisuudet ja haasteet sekä niiden vaikutukset työskentelyyn eroavat toisistaan. Suurimpia mahdollisuuksia olivat työskentelyn parantunut tehokkuus, kustannussäästöt sekä saadun informaation parempi laatu. Teoriassa haasteiksi koettiin koulutuksen puute ja työntekijöiden sekä asiakkaiden muutosvastarinta. Käytännössä suurimman haasteen sähköisen taloushallinnon käytettävyydelle kuitenkin aiheuttavat ohjelmistot ja niiden mukanaan tuomat ongelmat. Sähköistymisen myötä kirjanpitäjistä tulee teoriassa enemmänkin konsultteja ja tilitoimistoissakin työskentelee erikseen esimerkiksi reskontranhoitajia. Tosiasiassa roolien muuttuminen ei kuitenkaan ole aivan itsestään selvää ja sähköisiin järjestelmiin siirtymisen odotetaan kestävän vielä kauan.

Assessment of techno-economic use cases for small-scale island grids

The main objective of the study was to define the methodology for assessing the limits for application island grids instead of interconnecting with existing grid infrastructure. The model for simulation of grid extension distance and levelised cost of electricity has been developed and validated by the case study in Finland. Thereafter, sensitivities of the application limits were examined with the respect to operational environment, load conditions, supply security and geographical location. Finally, recommendations for the small-scale rural electrification projects in the market economy environment have been proposed.

Comparação entre modelos equivalentes de aerogeradores síncronos utilizando o programa ATP

At present, the electricity generation through wind energy has an importance growing in the world, with the existence of very large plans for future wind power installation worldwide. Thus, the increasing the electricity generation through wind power requires, more and more, analysis of studies of interaction between wind parks and electric power systems. This paper has as purposes to implement equivalent models for synchronous wind generators to represent a wind park in ATP program and to check behavior of the models through simulations. Simulations with applications of faults were achieved to evaluate the behavior of voltages of system for each equivalent model, through comparisons between the results of models proposed, to verify if the differences obtained allows the adoption of the simplest model

Optimal reactive power flow via the modified barrier Lagrangian function approach

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Allocation of protective devices in distribution circuits using nonlinear programming models and genetic algorithms

The optimized allocation of protective devices in strategic points of the circuit improves the quality of the energy supply and the system reliability index. This paper presents a nonlinear integer programming (NLIP) model with binary variables, to deal with the problem of protective device allocation in the main feeder and all branches of an overhead distribution circuit, to improve the reliability index and to provide customers with service of high quality and reliability. The constraints considered in the problem take into account technical and economical limitations, such as coordination problems of serial protective devices, available equipment, the importance of the feeder and the circuit topology. The use of genetic algorithms (GAs) is proposed to solve this problem, using a binary representation that does (1) or does not (0) show allocation of protective devices (reclosers, sectionalizers and fuses) in predefined points of the circuit. Results are presented for a real circuit (134 busses), with the possibility of protective device allocation in 29 points. Also the ability of the algorithm in finding good solutions while improving significantly the indicators of reliability is shown. (C) 2003 Elsevier B.V. All rights reserved.

Interior point algorithm for linear programming used in transmission network synthesis

This article presents a well-known interior point method (IPM) used to solve problems of linear programming that appear as sub-problems in the solution of the long-term transmission network expansion planning problem. The linear programming problem appears when the transportation model is used, and when there is the intention to solve the planning problem using a constructive heuristic algorithm (CHA), ora branch-and-bound algorithm. This paper shows the application of the IPM in a CHA. A good performance of the IPM was obtained, and then it can be used as tool inside algorithm, used to solve the planning problem. Illustrative tests are shown, using electrical systems known in the specialized literature. (C) 2005 Elsevier B.V. All rights reserved.

A new method for real time computation of power quality indices based on instantaneous space phasors

One of the important issues about using renewable energy is the integration of dispersed generation in the distribution networks. Previous experience has shown that the integration of dispersed generation can improve voltage profile in the network, decrease loss, etc. but can create safety and technical problems as well. This work report the application of the instantaneous space phasors and the instantaneous complex power in observing performances of the distribution networks with dispersed generators in steady state. New IEEE apparent power definition, the so-called Buchholz-Goodhue effective apparent power, as well as new proposed power quality (oscillation) index in the three-phase distribution systems with unbalanced loads and dispersed generators, are applied. Results obtained from several case studies using IEEE 34 nodes test network are presented and discussed. (C) 2006 Elsevier B.V. All rights reserved.

A geometric interpretation for transmission real losses minimization through the optimal power flow and its influence on voltage collapse

This work presents an approach for geometric solution of an optimal power flow (OPF) problem for a two bus system (a slack and a PV busses). Additionally, the geometric relationship between the losses minimization and the increase of the reactive margin and, therefore, the maximum loading point, is shown. The algebraic equations for the calculation of the Lagrange multipliers and for the minimum losses value are obtained. These equations are used to validate the results obtained using an OPF program. (C) 2002 Elsevier B.V. B.V. All rights reserved.

Alternative parameters for the continuation power flow method

The conventional Newton's method has been considered inadequate to obtain the maximum loading point (MLP) of power systems. It is due to the Jacobian matrix singularity at this point. However, the MLP can be efficiently computed through parameterization techniques of continuation methods. This paper presents and tests new parameterization schemes, namely the total power losses (real and reactive), the power at the slack bus (real or reactive), the reactive power at generation buses, the reactive power at shunts (capacitor or reactor), the transmission lines power losses (real and reactive), and transmission lines power (real and reactive). Besides their clear physical meaning, which makes easier the development and application of continuation methods for power systems analysis, the main advantage of some of the proposed parameters is that its not necessary to change the parameter in the vicinity of the MLP. Studies on the new parameterization schemes performed on the IEEE 118 buses system show that the ill-conditioning problems at and near the MLP are eliminated. So, the characteristics of the conventional Newton's method are not only preserved but also improved. (C) 2003 Elsevier B.V. B.V. All rights reserved.

Sensitivity analysis for transient stability studies

The paper presents a method for security control of electric power systems effected by generation reallocation, determined by sensitivity analysis and optimisation. The model is developed considering the dynamic aspects of the network (transient stability). Security control methodology is developed using sensitivity analysis of the security margin in relation to the mechanical power of synchronous machines in the system. The power reallocated to each machine is determined by means of linear programming. To illustrate the proposed methodology, an example is presented which considers a multimachine system composed of 10 synchronous machines, 45 buses, and 72 transmission lines, based on the configuration of a southern Brazilian system.

Generalization of the Y-differential autotransformer for 12- and 18-pulse converters

This work proposes a methodology to generalize the Y-connections for 12- and 18-pulse autotransformers. A single mathematical expression, obtained through simple trigonometric operations, represents all the connections. The proposed methodology allows choosing any ratio between the input and the output voltages. The converters can operate either as step-up or as step-down voltage. To simplify the design of the windings, graphics are generated to calculate the turn-ratio and the polarity of each secondary winding, with respect to the primary winding. A design example, followed by digital simulations, illustrates the presented steps. Experimental results of two prototypes (12 and 18 pulses) are presented. The results also show that high power factor is an inherent characteristic of multi-pulse converters, without any active or passive power factor pre-regulators needs. (c) 2005 Elsevier B.V. All rights reserved.