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Radikal högerpopulism i Sverige : En kvantitativ undersökning angående Sverigedemokraternas valresultat i kommunvalet 2006Ruth, Patrick January 2010 (has links)
Den här uppsatsen hade som syfte att undersöka sambandet mellan Sverigedemokraternas valresultat i kommunvalet 2006 och ett antal relevanta variabler utvalda i dialog med tidigare forskning och teoribildning angående väljarmobilisering för radikala högerpopulistiska partier (RHP). Sverigedemokraterna är landets största och mest inflytelserika RHP-parti och bygger sin politik framförallt kring en populistisk anti-etablissemangskritik samt en främlingsfientlighet grundad i den etno-pluralistiska doktrinen. Det finns många olika teorier angående väljarmobilisering för RHP-partier. Man har bl.a. menat att lågutbildade okvalificerade individer med små ekonomiska medel är mer benägna att rösta på RHP-partier än högutbildade och förhållandevis välbärgade individer. Arbetslöshet och nivå av invandring har därutöver lyfts fram som betydande förklaringsfaktorer. Yttermera har man menat att RHP-partier gagnas av lågt EU-stöd och höga nivåer av brottslighet inom den politiska enheten. Valdeltagande samt tidigare framgångar för RHP-partier inom den politiska enheten har även ansets ha en inverkan på den potentiella väljarmobiliseringen. De oberoende variablerna vilka ingår i undersökningen utgörs av medelinkomst, andel högutbildade, arbetslöshet, brottslighet, andel utrikesfödda invandrare, valdeltagande, tidigare valresultat för Ny demokrati samt andel nejröster i EMU-omröstningen. Undersökningen studerar sambandet mellan beroende och oberoende variabler genom linjär OLS multipel regressionsanalys där Sveriges 290 kommuner utgör observationsenheter. Datamaterialet för de olika variablerna är hämtad från statliga myndigheter såsom Statistiska centralbyrån, Brottsförebyggande rådet, Valmyndigheten och Arbetsförmedlingen. Undersökningen visar att medelinkomst, andel högutbildade och nivå av brottslighet har ett signifikant samband med Sverigedemokraternas valresultat inom kommunerna, med förväntad korrelationsriktning. Även andel utrikesfödda invandrare uppvisar ett signifikant samband, dock med en oväntad negativ korrelationsriktning. Däremot utgör valdeltagande och Ny demokratis valresultat inga signifikanta samband. Yttermera uppvisa andel nej i EMU-omröstningen ett signifikant samband. Emellertid anses detta vara ett skensamband vilket fångat upp andra faktorer vilka ej ingått i undersökningen.
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Radikal högerpopulism i Sverige. : En kvantitativ undersökning angående Sverigedemokraternas valresultat i kommunvalet 2006Ruth, Patrik January 2010 (has links)
Den här uppsatsen hade som syfte att undersöka sambandet mellan Sverigedemokraternas valresultat i kommunvalet 2006 och ett antal relevanta variabler utvalda i dialog med tidigare forskning och teoribildning angående väljarmobilisering för radikala högerpopulistiska partier (RHP). Sverigedemokraterna är landets största och mest inflytelserika RHP-parti och bygger sin politik framförallt kring en populistisk anti-etablissemangskritik samt en främlingsfientlighet grundad i den etno-pluralistiska doktrinen. Det finns många olika teorier angående väljarmobilisering för RHP-partier. Man har bl.a. menat att lågutbildade okvalificerade individer med små ekonomiska medel är mer benägna att rösta på RHP-partier än högutbildade och förhållandevis välbärgade individer. Arbetslöshet och nivå av invandring har därutöver lyfts fram som betydande förklaringsfaktorer. Yttermera har man menat att RHP-partier gagnas av lågt EU-stöd och höga nivåer av brottslighet inom den politiska enheten. Valdeltagande samt tidigare framgångar för RHP-partier inom den politiska enheten har även ansets ha en inverkan på den potentiella väljarmobiliseringen. De oberoende variablerna vilka ingår i undersökningen utgörs av medelinkomst, andel högutbildade, arbetslöshet, brottslighet, andel utrikesfödda invandrare, valdeltagande, tidigare valresultat för Ny demokrati samt andel nejröster i EMU-omröstningen. Undersökningen studerar sambandet mellan beroende och oberoende variabler genom linjär OLS multipel regressionsanalys där Sveriges 290 kommuner utgör observationsenheter. Datamaterialet för de olika variablerna är hämtad från statliga myndigheter såsom Statistiska centralbyrån, Brottsförebyggande rådet, Valmyndigheten och Arbetsförmedlingen. Undersökningen visar att medelinkomst, andel högutbildade och nivå av brottslighet har ett signifikant samband med Sverigedemokraternas valresultat inom kommunerna, med förväntad korrelationsriktning. Även andel utrikesfödda invandrare uppvisar ett signifikant samband, dock med en oväntad negativ korrelationsriktning. Däremot utgör valdeltagande och Ny demokratis valresultat inga signifikanta samband. Yttermera uppvisa andel nej i EMU-omröstningen ett signifikant samband. Emellertid anses detta vara ett skensamband vilket fångat upp andra faktorer vilka ej ingått i undersökningen.
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Quantifying the benefits of greywater systemsWickstead, Frank Anthony 05 April 2011 (has links)
This thesis offers a decision support framework to establish the economic feasibility associated with considering the installation of a greywater system. Because of the potential dangers and lack of widespread knowledge of greywater systems, the study begins by providing an explanation of current greywater technology to include the history of the technology, an explanation of greywater as opposed to reclaimed water, the potential risks of greywater use, and the necessary components of a greywater system.
This decision support framework can be used with any scale of greywater system to be installed within any scale of facility. The example of an typical Atlanta, Georgia, USA multifamily rental development is used within the study to explain the framework by showing a working model. The need for water conservation in Georgia is shown and how greywater use dovetails with the need to lower overall usage. The legality of greywater use in Georgia along with the specific legal uses is also shown. The findings are then made State of Georgia and use specific to a multifamily development.
The decision support framework provided is a viable tool. The sample framework in chapter 5 shows that the implementation of a greywater unit in the sampled facility would save 5,060,739.6 gallons of potable water per year with a 10.49 year payback cycle.
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Reliability Constrained Optimal Investment in a Microgrid with Renewable Energy, Storage, and Smart Resource Management2015 September 1900 (has links)
Environmental concerns have led to a rapid increase in renewable energy development and production as the global demand for electricity continues to increase. The intermittent and uncertain nature of electricity generation from renewable sources, such as wind and solar, however, create significant challenges in maintaining power system reliability at reasonable costs. Energy storage and smart-grid technologies are perceived to provide potential solutions to these challenges in modern power systems of different sizes. This work investigates the opportunity to incorporate energy storage in microgrids with renewable energy production, as well as applying smart microgrid management techniques to reduce the lifetime costs while maintaining an acceptable level of reliability.
A microgrid consisting of a 5 home community with generation supplied by two propane generators to meet the “N-1” reliability criterion is used as the base case scenario. Actual load data of typical homes is obtained from the industry partner. An equivalent loss of load expectation criterion is used to benchmark the acceptable reliability level. A model is developed to calculate the lifetime operational cost of the base case scenario which is used to assess the benefit of the addition of renewable energy sources, energy storage, and smart microgrid management techniques.
A MATLAB program is developed to assess the 20 year operational costs of various combinations of renewable energy sources and battery energy storage, which will be considered the lifetime of the system. The combination of generation and storage which yields the lowest lifetime operational cost is defined as the optimized microgrid, and is used as a basis to determine if additional savings are realized by the implementation of a microgrid operated by a Smart Microgrid Management System (SMMS).
The conceptual layout of the proposed SMMS is presented along with identified methods of utilizing in-home thermal storage. The SMMS mechanism is discussed along with proposed functionality, potential methods of employment, and associated development and implementation costs. The microgrid operated by the SMMS is assessed, and its lifetime operational cost is presented and contrasted against the base case microgrid and the optimized microgrid.
A power system reliability evaluation of the proposed microgrids are conducted using a probabilistic method to ensure that reliability is not sacrificed by the implementation of a cost-minimized microgrid. A sequential Monte Carlo simulation model is developed to assess the power system reliability of the various microgrid configuration cases. The functionality of this model is verified using an existing reliability assessment program.
The results from the presented studies show that the implementation of renewable energy sources, energy storage, and smart microgrid management techniques are an effective way of reducing the operational cost of a remote microgrid while increasing its power system reliability.
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Energitjänst för efterfrågeflexibilitet : Som leder till en effektivare elnätsanvändning / Energy service for demand-side flexibility : Resulting in a more efficient use of the electrical gridNilsson, Martin, Samuelsson, Simon January 2015 (has links)
The load in the electricity grid fluctuates during the day and between seasons. As a distribution system operator (DSO), an uneven load profile leads to increased transmission losses and unnecessary high costs for subscribing power from the feeding grid. Efficiency measures and a more even power consumption by the end-users, could therefore lead to that a DSO can achieve lower costs for power-subscription from the feeding grid and transmission losses, but also implies a lowered cap of total revenues. As a step towards implementing the EU energy efficiency directive, the Energy Markets Inspectorate (Ei) have developed two economic incentives which enables for DSOs to profit economically from cost reductions related to transmission losses and feeding grid. For this reason the electricity suppliers Storuman Energi and Affärsverken Energi sees a possibility to offer a load shift-service to low voltage DSOs using the flexibility in the demand of electrically heated households. The aim of this study is therefore to demonstrate how a service such as this one can be valued in the Swedish electricity market. The task at hand was examined by conducting a survey of the values of demand-side flexibility, as well as an investigation of how the costs for the end-user and incentives for the DSO are affected by flexibility. A review of the values associated with demand-side flexibility has been conducted for electricity suppliers, DSOs and end-users. With regard to the DSOs, the main value is connected to the new economic incentives from Ei, whose potential depends on the properties of the grid and the tariff for the feeding grid. Other values related to operation and delivery reliability can also be achieved. The main values for electricity suppliers are a lowered risk for unbalance following as a consequence of better knowledge of their end-users’ usage, and also the possibility to profit by offering a load shift-service. The values for end-users have been divided between cost reductions and system benefits, both of which are regarded to compensate the remuneration end-users require to offer their flexibility. By adapting consumption after the spot market price or the grid tariff, lowered costs for electricity can be achieved. The end-users can also appreciate system-benefits such as the facilitation for intermittent renewable electricity production, electric vehicles and reducing the societal dependency on expensive fossil-fuelled power generation as positive. They do on the other hand regard a possible depreciation of the heat comfort, data confidentiality and reduced control over one’s own electricity consumption as negative. If the service can be bundled with equipment which yields other values, such as an increased heat comfort, the end-users’ demand for remuneration can decrease. To explore what effects demand-side flexibility can have on the electricity costs of end-users and the economic incentives for DSOs, a case study is conducted in the electricity distribution grid of Karlskrona. Through review of previous studies, a potential for demand reductions was established and used as input in the case study. It can be determined that the incentive for a more even load profile constitutes a substantially greater share of the total incentives, compared to the incentive for reduced distribution losses. It is further concluded that a fairly large part of the incentives can be achieved by controlling the end-users on only a few occasions each year. It is also established that the cost reductions for end-users can match their demand for remuneration. A future scenario with more electrical vehicles connected to the grid for charging, greatly increases the possible benefits for both the DSO and end-users. Through the investigation of different possible designs for the energy service, it is recommended that the demand side management of end-users is placed in the hands of an electricity supplier responsible for balancing the consumption of the end-users. A procurement-procedure is deemed problematicfollowing the risk for unproportional use of resources and time. As a result of this, the energy service should not be traded directly between DSOs and electricity suppliers. Instead, it is proposed that the DSO develops a time-differentiated tariff, after which the electricity supplier can adapt the end-users’ consumption. Since the results indicate that controlling the end-users consumption on just a few occasions is sufficient to yield large benefits for the DSO, a grid-tariff with critical peak pricing is recommended. This tariff employs a high price for shorter periods of time when the grid load is peaking and a rebated price during all other occasions. This opens up for controlling the use during the other days according to the spot market price. As the electricity supplier grants the end-user lowered costs for both the electricity grid and trading, they have the opportunity to apply a charge for the service. Both the DSO, end-user and electricity supplier is presumed to improve their profitability with this design. When implementing the energy service, a couple of aspects are important to shed light on. The grid-tariff of the end-user and the tariff for the feeding grid needs to be synchronized with each other, to stimulate the same type of load shifts. It should also be noted that the possible gain from the incentives will decrease as demand side management-measures is taken since the reference-level from which a comparison is made improves. Another interesting aspect is that the regulation stipulates that only a certain percentage of the cost reductions will result in incentives, thus limiting the amount of profitable measures. Since the costs and revenues between the actors in the transmission system (low and medium voltage DSOs and the TSO) are interdependent, the revenue loss for the medium voltage DSO resulting from the cost reduction for the low voltage DSO, can result in a recoil effect. Lastly, a widespread introduction of control equipment to end-users can facilitate other uses for the demand-side flexibility. / Belastningen i elnätet varierar under dagen och mellan olika säsonger. Att som nätägare ha en ojämn belastning i sitt nät leder till ökade nätförluster och onödigt höga kostnader för att abonnera effekt från det överliggande nätet. Effektiviseringar i nätet och ett jämnare effektuttag av användarna kan därmed leda till att en nätägare kan erhålla minskade kostnader för abonnerad effekt från överliggande nät och nätförluster, men innebär också en sänkt intäktsram för nätägaren. Vid implementering av EU:s energieffektiviseringsdirektiv har Energimarknadsinspektionen tagit fram två ekonomiska incitament som möjliggör för nätägare att dra nytta av kostnadsminskningar för nätförluster och överliggande nät. Av denna anledning ser elhandelsbolagen Storuman Energi och Affärsverken Energi möjligheter att, med hjälp av efterfrågeflexibilitet hos framförallt eluppvärmda hushåll, erbjuda en laststyrningstjänst till lokalnätsnätägare. Syftet med denna studie är därmed att demonstrera hur en tjänst som denna kan värdesättas av aktörerna på den svenska elmarknaden. Frågan behandlas genom att undersöka vilka värden efterfrågeflexibilitet kan ge upphov till, exempelvis hur slutanvändares elkostnader och nätägares ekonomiska incitament påverkas av efterfrågeflexibilitet. En inventering har gjorts av efterfrågeflexibilitetens värde för elhandlare, nätägare och slutanvändare. För nätägare bedöms de huvudsakliga värdena finnas kring de nya ekonomiska incitamenten, vars potential beror på nätets förutsättningar och regionnätstariffen. Det finns också nyttor kopplade till driftsäkerhet och leveranskvalitet. Elhandlare kan dra nytta av en lägre risk för obalans genom att de får bättre uppfattning om sina kunders användningsmönster, samt möjligheten att även debitera för utförd laststyrningstjänst. För slutanvändare har värdena delats upp i kostnadsminskningar och systemnyttor. Båda dessa anses kunna kompensera för de krav på ersättning som slutanvändare har för att bidra med sin flexibilitet. Genom anpassning efter exempelvis spotpris eller en nättariff kan lägre kostnader för elhandel respektive nät erhållas. Vad gäller systemnyttor kan följder som att exempelvis främja intermittent förnybar elproduktion, underlätta införande av en eldriven fordonsflotta samt att minska beroendet av dyra fossileldade produktionsslag ses som positiva. Å andra sidan bedöms en upplevd risk för försämrad värmekomfort och datasekretess samt minskad kontroll över sin användning spela in som negativa värden. Om tjänsten kan paketeras tillsammans med utrustning som även ger andra mervärden, exempelvis möjliggör en ökad värmekomfort, kan slutanvändares ersättningskrav minska. För att utreda vilken konkret påverkan efterfrågeflexibilitet kan ha på slutanvändares elkostnader och nätägares ekonomiska incitament görs en undersökning i Karlskronas lokalnät. Där appliceras den potential för efterfrågeflexibilitet som tidigare studier visat på. Det konstateras att incitamentet för jämnare nätbelastning visar betydligt större potential än det för minskade nätförluster samt att en stor del av incitamenten går att erhålla genom att styra endast ett fåtal tillfällen varje år. Vidare pekar resultatet på att slutanvändares kostnadsminskningar kan nå upp i nivåer som motsvarar deras ersättningskrav. Ett framtidsscenario med fler elfordon ger mycket större ekonomisk potential för både nätägare och slutanvändare. Efter att ha utrett olika alternativa utformningar för energitjänsten föreslås att passiv efterfrågeflexibilitet tillämpas genom att laststyrning av slutanvändare sker av en elhandlande aggregator med balansansvar. Ett upphandlingsförfarande bedöms medföra risk för stor resurs- och tidsåtgång, varför handel av tjänsten inte bör äga rum mellan elhandlare och nätägare. Men för att elhandlare ändå ska kunna ta del av värdet från de ekonomiska incitamenten föreslås att nätägaren tar fram en tidsdifferentierad nättariff, vilken elhandlaren kan laststyra slutanvändare efter. Då resultatet pekar på att styrning under endast ett fåtal tillfällen är erforderligt kan en nättariff av typen spetspristariff tillämpas, där kostnaden för effektuttag kraftigt stiger när belastningen är hög i nätet. Då möjliggörs styrning efter exempelvis spotpris de tillfällen som inte är nödvändiga att styra med hänsyn till nätet, eftersom kostnaden för effektuttag då är låg. Genom att elhandlare på så sätt kan erbjuda slutanvändare lägre kostnader för både nät och elhandel har de möjlighet att debitera slutanvändare en avgift för utförd tjänst. Med denna utformning anses både nätägare, elhandlare och slutanvändare kunna nå en ökad lönsamhet. Vid införandet av energitjänsten är ett antal aspekter viktiga att belysa. Slutanvändares nättariff och lokalnätets tariff för överliggande nät spelar en viktig roll då de behöver stimulera till att samma styrning utförs, exempelvis om det är fördelaktigt att styrning sker ofta eller mer sällan. Då incitamentens nivå bestäms utifrån en referensperiod kommer möjlig avkastning att avta i takt med att förbättringar görs. I nätregleringen är det fastställt att bara en viss del av kostnadsbesparingarna erhålls i form av de ekonomiska incitamenten, vilket innebär att vilka åtgärder som är lönsamma begränsas. Genom att kostnader och intäkter är tätt sammankopplade mellan aktörerna i elnätet (lokal-, region- och stamnät) kan regionnätets intäktsbortfall till följd av lokalnätets lägre kostnader, ge upphov till rekyleffekter. Att storskaligt installera styrutrustning hos slutanvändare kan också möjliggöra andra användningsområden, med andra ord skapas det en plattform för efterfrågeflexibilitet.
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Developing ESCO procedures for large telecommunication facilities using novel simulation techniques / Johann Francois van RensburgVan Rensburg, Johann Francois January 2006 (has links)
Peak electricity demand in South Africa will exceed the available operational generation
capacity in 2007. The state utility Eskom is addressing this challenge, inter aha, with the
implementation of the Demand-side Management (DSM) initiative. The aim of DSM is to defer
the building of additional power stations by modifying the end-user pattern to reduce
electrical load during the morning and evening peaks. At the end of 2005 the DSM
programme has only achieved 30°/o of its target. Some of the biggest problems are the lack of
knowledge on how to perform ESCO audits and availability of tools and procedures to enable
Energy Service Companies (ESCOs) to evaluate DSM potential.
Studies in South Africa have shown that 20°/o of the total municipal energy is utilised in
commercial buildings. Additional investigations have shown that in the commercial sector
approximately 50% of energy is used for air conditioning. Energy savings of around 30% can
be realised through improved management procedures and retrofit projects of HVAC systems
of existing buildings.
Telecommunication companies own and operate a large portfolio of diverse buildings. It was
shown that these buildings are very inefficient in terms of energy usage. Performing ESCO
analyses on these building portfolios present huge savings opportunities for the building
owners as well as load reduction opportunities to help meet DSM targets.
ESCOs however face major problems in evaluating DSM projects on telecommunication
facilities. Some of these problems are: time to perform the ESCO audits on such a large
portfolio of buildings; skill levels of available personnel; lack of experience and structured
audit process; availability of information; data capturing of information; determining the
impact of the retrofits and calculating the savings and financial benefits of retrofits.
Obtaining approval for DSM projects is also a lengthy process. Smaller ESCOs cannot afford to
commit resources to ESCO investigations only to recover their investment after project
approval. Having an ESCO procedure that will speed up the audit process will help the ESCO
to minimise resources that need to be committed to these investigations. Having a tested and
reliable ESCO procedure will also help Eskom since they will receive more and better quality
DSM proposals.
A new ESCO procedure for telecommunications facilities was developed. The primary
requirements for the new ESCO procedure are that it should be simple, stable, fast and
accurate. This procedure is evaluated against the known energy management opportunities in
telecommunication facilities.
Some of the benefits of the new ESCO procedure are: time taken to perform ESCO analysis on
all types of buildings is drastically reduced; lower qualified personnel can be used to perform
the ESCO analysis; any type of HVAC system configuration can be accommodated; new data
capturing procedures ensure that only essential data is captured; integrated simulation
software is used that can easy and accurately simulate the building operations and retrofits on
a building; retrofit options suitable for telecommunication facilities are identified; contribution
to the DSM programme is evaluated; financial evaluation of the retrofits and feasibility for
DSM funding and results are integrated into a standardised reporting format.
The new ESCO procedure was implemented on several case studies within the
telecommunication infrastructure. Five different types of buildings were selected to implement
the ESCO procedure. Each step of the procedure was evaluated and tested against the
requirements of the new ESCO procedure.
It was proven through implementation that the new ESCO procedure is successful in solving
the unique problems in performing ESCO analyses for telecommunications facilities. Valuable
insight into the problems that can occur during the ESCO process was highlighted, and
recommendation for future work was presented. / Thesis (Ph.D. (Electrical Engineering))--North-West University, Potchefstroom Campus, 2006.
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Development of an energy management solution for mine compressor systems / Johan Nicolaas du PlessisDu Plessis, Johan Nicolaas January 2010 (has links)
Eskom is under increasing pressure to provide reliable and sustainable electricity. Demand Side
Management (DSM), offers a short– to medium–term solution to this problem. During 2009, the mining
sector consumed approximately 16% of the domestic electricity supplied by Eskom. This made the
mining sector one of the major targets for Eskom–initiated DSM programmes.
The mining industry uses compressed air for a wide variety of applications and production purposes. This
creates many opportunities to reduce electricity consumption and operating costs. Reducing the airsystem
demand may however not result in significant electrical energy savings, unless the compressed–air
supply is accurately managed to meet the reduced demand.
Until recently, compressor control in the mining sector generally consisted of operating the compressors
continuously, regardless of the actual demand for compressed air. Excessive compressed air is blown off
into the atmosphere resulting in energy loss. This usually occurs when the compressors are operated
manually.
A computer–controlled compressor management solution, which optimises the efficiency potential of the
compressed–air supply, is required to obtain significant electrical energy savings. The need for such a
solution was addressed by the development of an energy management solution for mine compressor
systems. This solution is referred to as Energy Management System (EMS) and is capable of starting,
stopping, loading and unloading compressors. In addition to this, compressor output can be controlled to
maintain a desired pressure set–point.
In this study, the development and implementation of EMS on ten different mine compressor systems is
presented. Automatic compressor capacity control was implemented, while an operator manually initiated
compressor starting; stopping; loading and unloading, according to EMS control schedules.
Centralised compressor control is one of the main advantages offered by EMS, especially for
compressed–air systems with multiple compressor systems at different geographic locations. EMS
facilitated effective and sustainable electrical energy reductions for all these compressed–air systems. / Thesis (M. Ing. (Computer and Electronical Engineering))--North-West University, Potchefstroom Campus, 2011.
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Development of an energy management solution for mine compressor systems / Johan Nicolaas du PlessisDu Plessis, Johan Nicolaas January 2010 (has links)
Eskom is under increasing pressure to provide reliable and sustainable electricity. Demand Side
Management (DSM), offers a short– to medium–term solution to this problem. During 2009, the mining
sector consumed approximately 16% of the domestic electricity supplied by Eskom. This made the
mining sector one of the major targets for Eskom–initiated DSM programmes.
The mining industry uses compressed air for a wide variety of applications and production purposes. This
creates many opportunities to reduce electricity consumption and operating costs. Reducing the airsystem
demand may however not result in significant electrical energy savings, unless the compressed–air
supply is accurately managed to meet the reduced demand.
Until recently, compressor control in the mining sector generally consisted of operating the compressors
continuously, regardless of the actual demand for compressed air. Excessive compressed air is blown off
into the atmosphere resulting in energy loss. This usually occurs when the compressors are operated
manually.
A computer–controlled compressor management solution, which optimises the efficiency potential of the
compressed–air supply, is required to obtain significant electrical energy savings. The need for such a
solution was addressed by the development of an energy management solution for mine compressor
systems. This solution is referred to as Energy Management System (EMS) and is capable of starting,
stopping, loading and unloading compressors. In addition to this, compressor output can be controlled to
maintain a desired pressure set–point.
In this study, the development and implementation of EMS on ten different mine compressor systems is
presented. Automatic compressor capacity control was implemented, while an operator manually initiated
compressor starting; stopping; loading and unloading, according to EMS control schedules.
Centralised compressor control is one of the main advantages offered by EMS, especially for
compressed–air systems with multiple compressor systems at different geographic locations. EMS
facilitated effective and sustainable electrical energy reductions for all these compressed–air systems. / Thesis (M. Ing. (Computer and Electronical Engineering))--North-West University, Potchefstroom Campus, 2011.
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Smart Grids et efficacité des systèmes électriques : instruments de régulation et impacts de la gestion de la demande / Smart grids and power systems efficiency : regulatory tools and demand-side management impactsBergaentzle, Claire 23 June 2015 (has links)
L'architecture physique des réseaux électriques et les structures organisationnelles des industries électriques survenues à la suite des réformes ont principalement été conçues en fonction des caractéristiques relatives aux infrastructures de transport et aux parcs de production. Or, les nouveaux enjeux de transition énergétique, associés aux progrès réalisés dans les équipements de communication et d'automatisation, plaident pour une plus grande participation des activités décentralisées de production et des consommateurs finals. Nous constatons que les systèmes électriques sont à l'aube d'évolutions majeures qui partagent une double caractéristique. La première et que ces évolutions nécessiteront des apports en capitaux considérables pour adapter et moderniser les réseaux de distribution. La seconde est que l'activation de l'aval de la chaîne électrique libère des gains d'efficacité économique actuellement inexploités, mais est également porteuse de contraintes nouvelles.Partant de ce constat, l'objectif de cette thèse est double. Il s'agit dans un premier temps de proposer une analyse théorique des instruments de régulation qui encadrent et orientent les dépenses des opérateurs réseau. Nous cherchons en nous appuyant sur la littérature à caractériser les outils de régulation les mieux adaptés à l'investissement en smart technologies. Puisqu'il est nécessaire de confronter l'analyse théorique aux faits, nous entreprenons de recenser les gains clés d'efficacité économique escomptés de la généralisation des smart grids. Nous illustrons chacun de ces gains par une étude empirique qui nous permet de comparer les résultats issus de notre analyse théorique aux schémas de régulation existants et de formuler un certain nombre de recommandations.Le second objectif de la thèse se concentre sur les impacts de la diffusion de programmes de la gestion de la demande. Le raisonnement adopté s'articule autour de deux constats. D'importants bénéfices sont attendus des réductions substantielles des pointes de demande, réductions qui se traduisent par de moindres opportunités de profit pour les producteurs. Il s'agira de réaliser une estimation des gains et pertes que l'on peut attendre de la gestion de la demande. Pour cela, nous développons et utilisons un modèle d'optimisation dans lequel nous intégrons plusieurs pays interconnectés dotés de parcs de production différenciés.La thèse montre que les cadres de régulation dominants actuellement sont limités dans leur portée incitative pour favoriser un investissement efficace dans la technologie, ce qui est susceptible de retarder son introduction. La quantification des impacts de la gestion de la demande montre quant à elle que des efficacités significatives peuvent être activées via la généralisation de ces mesures. Toutefois, elles posent des problèmes nouveaux dans la rémunération de l'existant, l'adéquation future des capacités, et souligne l'antagonisme potentiel entre perte de revenus pour les unités de pointe les plus réactives et développement des énergies bas carbone.De toute évidence, les interrogations soulevées par le développement des smart grids nécessitent que soit mené un débat politique éclairé puisque l'industrie électrique est indispensable à nos sociétés. Parmi le nombre considérable d'éléments à aborder, arriveront en bonne place les questions relatives au financement des projets d'investissement et à l'inclusion des nouvelles sources de flexibilité induites par l'adoption de la technologie dans les marchés électriques libéralisés. / The physical architecture of electricity grids and the organizational structure of power systems implemented after the reforms have traditionally be achieved according to the characteristics of the transmission infrastructures and power mixes. However, the new challenges related to energy transition favor a greater participation of decentralized generation and final consumers to system exploitation and competitive markets. This latter participation is made possible thanks to recent innovations in the fields of communication and remote control technologies.Significant evolutions are expected in power industries that share common characteristics. First, these evolutions suppose massive capital investments to modernize and adapt current power distribution grids. Second, it is expected the activation of distribution grids and final consumers will unleash substantial unexploited economic efficiency gains as well as impose new constraints.Taking these simple facts as a starting point, the objective of the thesis is twofold. In the first place, we provide a theoretical analysis of the regulatory instruments that monitor the system operators' expenses. Relying on the literature, we aim at characterizing what regulatory tools and incitation are suitable for investing in smart grids technologies. Since it is necessary to compare theoretical formulation to facts, we use an empirical approach that allows us to designate key benefits pursued by the development of smart grids and to compare our theoretical results with practical regulatory applications. Our findings eventually allow us to formulate recommendations.In the second place, the thesis focuses on the impacts of demand-side management during peak periods. We structure our approach around two general observations. Large benefits should be generated in lowering substantially peak demand. However, such situation also creates losses of profit for generators. We provide an estimation of efficiency gains and revenue losses induced by peak shedding. To this end, we develop and use a linear optimization model and expand our analysis to interconnected countries endowed with differentiated generation means.The thesis shows dominant regulatory frameworks are unsuited to provide the necessary sets of incentive to efficiently develop smart technologies. This can cause delays in their integration to power grids. The quantitative evaluation of the impacts generated by demand-side management shows significant efficiency gains are achievable through final consumers' flexibility. However, such measures create new discrepancies regarding installed capacities profitability, future capacity adequacy, and highlight potential antagonism between missing money for flexible peak capacities and the development of low carbon energies.It is clear the issues raised by the development of smart grids call for informed public debate as power industries are essential to our societies. Among the considerable amount of elements to discuss, issues relative to financing the investment projects and the inclusion of the new sources of flexibility induced by the technology in competitive markets will be of priority.
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Environmental performance improvement in the cement industrySummerbell, Daniel Leo January 2018 (has links)
This research investigates ways to reduce the carbon dioxide emissions from the cement industry. Cement is one of the largest sources of man-made greenhouse gases, contributing ~5% of the global total. 40% of emissions from cement come from the fuel used in the process, while the electricity used contributes a further 5%. The focus of the research is to find operational changes that can reduce emissions without the need for large capital investment. Three cement plants in the UK were investigated using four different mathematical models based on real data from the plants. A new metric for assessing the environmental impact of the fuel mix of a plant was proposed, and evidence indicates that it may be a better predictor of environmental performance than the metrics currently used in industry. The research found that consistently improving this fuel metric to best-observed levels, as well as reducing the excess air ratio to industry-standard levels had the potential to reduce fuel consumption by up to 7%, and fuel derived CO2 emissions by up to 12%. Increasing use of biomass to best-observed levels had the potential to reduce the net fuel derived CO2 emissions by up to 20%. Comparing the proposed improvements to the historic range of plant performance showed that this level of performance is within the normal operating range of the plants. A reduction of 2-4% in electricity costs and electricity derived emissions was also possible from operational changes. These savings would reduce operating costs as well as emissions, and require little to no capital investment, meaning they could be implemented directly. If successfully implemented in the near future the total savings by 2050 would be on a similar scale to those expected from much more expensive technology changes, such as upgrading to new cement plants, or installing carbon capture and storage technology.
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