Examining methods for controlling the electricity demand in Kuwait was the main objective and motivation of this researchp roject. The extensiveu se of air-conditioning for indoor cooling in office and large commercial buildings in Kuwait and the Gulf States represents a major part of the power and electricity consumption in such countries. The rising electricity generation cost and growing rates of consumption continuously demand the construction new power plants. Devising and enforcing Demand-SideM anagemen(t DSM) in the form of energye fficient operations trategies was the response of this research project to provide a means to rectify this situation using the demand-side management technique known as demand levelling or load shifting. State of the art demand-sidem anagementte chniquesh ave been examined through the developmenot f a model basedp redictive control optimisations trategyf or an integrateda ndm odulara pproachto the provisiono f ice thermals torage. To evaluate the potential of ice-storage assisted air-conditioning systems in flattening the demand curve at peak times during the summer months in Kuwait, a model of a Heating, Ventilation, and Air-conditioning (HVAC) plant was developed in Matlab. The model engaged the use of model based predictive control (MPQ as an optimisation tool for the plant as a whole. The model with MPC was developed to chose and decide on which control strategy to operate the integrated ice-storage HVAC plant. The model succeeded in optimising the operation of the plant and introduced encouraging improvement of the performance of the system as a whole. The concept of the modular ice-storage system was introduced through a control zoning strategy based on zonal orientation. It is believed that such strategy could lead to the modularisation of ice-storage systems. Additionally, the model was examined and tested in relation to load flattening and demonstrated promising enhancement in the shape of the load curve and demonstrated flattened demand curves through the employed strategy. When compared with measured data from existing buildings, the model showed potential for the techniques utilised to improve the load factor for office buildings.

Communications receivers that rely on 1-bit analogto-digital conversion are advantageous in terms of hardware complexity and power dissipation. Performance limitations due to the 1-bit quantization can be tackled with oversampling. This paper considers the oversampling gain from an information-theoretic perspective by analyzing the channel capacity with 1-bit quantization and oversampling at the receiver for the particular case of AWGN channels. This includes a numerical computation of the capacity and optimal transmit symbol constellations, as well as the derivation of closed-form expressions for large oversampling ratios and for high signal-to-noise ratios of the channel.

The aim of this work is to make some investigations concerning duality for multiobjective optimization problems. In order to do this we study first the duality for scalar optimization problems by using the conjugacy approach. This allows us to attach three different dual problems to a primal one. We examine the relations between the optimal objective values of the duals and verify, under some appropriate assumptions, the existence of strong duality. Closely related to the strong duality we derive the optimality conditions for each of these three duals. By means of these considerations, we study the duality for two vector optimization problems, namely, a convex multiobjective problem with cone inequality constraints and a special fractional programming problem with linear inequality constraints. To each of these vector problems we associate a scalar primal and study the duality for it. The structure of both scalar duals give us an idea about how to construct a multiobjective dual. The existence of weak and strong duality is also shown. We conclude our investigations by making an analysis over different duality concepts in multiobjective optimization. To a general multiobjective problem with cone inequality constraints we introduce other six different duals for which we prove weak as well as strong duality assertions. Afterwards, we derive some inclusion results for the image sets and, respectively, for the maximal elements sets of the image sets of these problems. Moreover, we show under which conditions they become identical. A general scheme containing the relations between the six multiobjective duals and some other duals mentioned in the literature is derived. / Das Ziel dieser Arbeit ist die Durchführung einiger Untersuchungen bezüglich der Dualität für Mehrzieloptimierungsaufgaben. Zu diesem Zweck wird als erstes mit Hilfe des so genannten konjugierten Verfahrens die Dualität für skalare Optimierungsaufgaben untersucht. Das erlaubt uns zu einer primalen Aufgabe drei unterschiedliche duale Aufgaben zuzuordnen. Wir betrachten die Beziehungen zwischen den optimalen Zielfunktionswerten der drei Dualaufgaben und untersuchen die Existenz der starken Dualität unter naheliegenden Annahmen. Im Zusammenhang mit der starken Dualität leiten wir für jede dieser Dualaufgaben die Optimalitätsbedingungen her. Die obengenannten Ergebnisse werden beim Studium der Dualität für zwei Vektoroptimierungsaufgaben angewandt, und zwar für die konvexe Mehrzieloptimierungsaufgabe mit Kegel-Ungleichungen als Nebenbedingungen und für eine spezielle Quotientenoptimierungsaufgabe mit linearen Ungleichungen als Nebenbedingungen. Wir assoziieren zu jeder dieser vektoriellen Aufgaben eine skalare Aufgabe für welche die Dualität betrachtet wird. Die Formulierung der beiden skalaren Dualaufgaben führt uns zu der Konstruktion der Mehrzieloptimierungsaufgabe. Die Existenz von schwacher und starker Dualität wird bewiesen. Wir schliessen unsere Untersuchungen ab, indem wir eine Analyse von verschiedenen Dualitätskonzepten in der Mehrzieloptimierung durchführen. Zu einer allgemeinen Mehrzieloptimierungsaufgabe mit Kegel-Ungleichungen als Nebenbedingungen werden sechs verschiedene Dualaufgaben eingeführt, für die sowohl schwache als auch starke Dualitätsaussagen gezeigt werden. Danach leiten wir verschiedene Beziehungen zwischen den Bildmengen, bzw., zwischen den Mengen der maximalen Elemente dieser Bildmengen der sechs Dualaufgaben her. Dazu zeigen wir unter welchen Bedingungen werden diese Mengen identisch. Ein allgemeines Schema das die Beziehungen zwischen den sechs dualen Mehrzieloptimierungsaufgaben und andere Dualaufgaben aus der Literatur enthält, wird dargestellt.

Tomtmarkerna i urban bebyggelse blir allt mer attraktiva. En minskning av byggnadsarean medger positiva ekonomiska effekter på markkostnaden då tomtpriserna tenderar att bli allt högre i stadsmiljö. En stor del av totalkostnaden vid nyproduktionen av ett enbostadshus är tomtpriset. Framtidens enbostadshus bör utformas med ett begränsat tomtbehov samt uppfylla framtida energikrav.   Examensarbetet har utförts i samarbete med småhustillverkaren Eksjöhus, vilka till följd av de ökade markpriserna upplever en minskad efterfrågan för nyproduktion av småhus. Likt övriga hustillverkare står Eksjöhus också inför uppfyllandet av framtida energikrav.   Syftet med examensarbetet är att utforma framtidens enbostadshus, genom att effektivisera tomtutnyttjandet och förbättra energiprestandan. Frågeställningarna vilka besvaras i arbetet är ”Vilken är den minsta möjliga bostadsarean för entréplanet i ett enbostadshus, med bibehållen tillgänglighet enligt svenska krav?”, ”Hur kan rumsfunktionerna disponeras för ett enbostadshus i tre våningar med bibehållna boendekvalitéer?”, ”Hur kan ett enbostadshus utformas för att klara EUs direktiv för år 2020 beträffande byggnaders energiprestanda?”. Målet med arbetet är att utforma ett enbostadshus i tre våningar med minsta möjliga bostadsarea på entréplanet, som klarar EUs direktiv för år 2020 beträffande byggnaders energiprestanda.   En litteraturstudie genomfördes för att utreda kompaktboendets effekter på boendekvalitén samt energieffektiv byggnadsutformning. En fallstudie av tre byggnader utreddes boende i flera plan. Utformningen av framtidens enbostadshus genomfördes i ett skissarbete och slutligen beräknades byggnaden för att uppfylla den rådande kravspecifikationen för NNE-hus.   En yteffektiv planutformning åstadkoms genom överlappandet av betjäningsareor, effektiv disposition av rumsfunktioner samt gemensamma kommunikationsytor. Entréplanets utformning resulterade i en bostadsarea på 51,4 m2. Byggnaden är utformad för att tillgodose kravet på tillgänglighet i enlighet med BBR och SIS. Rumsfunktionerna som finns representerade på entréplanet är kök, badrum, avskiljbar sängplats samt utrymme för sittgrupp, matplats, tvätt och förvaring. Plan 2 utgörs till största del av ett vardagsrum vilket knyts samman med entréplanets sociala funktioner. Byggandens privata våning utgörs av plan 3 vilket inrymmer två av byggandens tre sovrum.   Byggnaden följer nu gällande krav för 2020-målet, utformat som ett NNE-hus genom en energieffektiv utformning och egenproduktion av el från solceller. Vår slutsats är att förhållande, disponering, kommunikation av rumsfunktioner samt åtskild placering av privata och sociala utrymmen är väsentligt för att minimera bostadsarean samt för att bibehålla en god bostadskvalité. / Building plots in urban settlements are becoming more attractive. A reduction of the gross floor area allows a positive economic impact on the cost when the prices tend to become high in urban settlements. A large amount of the total cost for the production of a new one-family house is the price of the building plot. The future one-family house should be designed with a limited need of land and also meet future energy demands.   The work was performed in collaboration with the small house manufacturer Eksjöhus, which due to the increased price of land are experiencing a decline in demand for construction of new one-family houses. Like the rest of the small house manufacturer, Eksjöhus are also facing the fulfillment of future energy requirements.   The purpose of this study is to design tomorrow's one-family house, by increasing the efficiency of land use and to improve the energy performance. The questions, which are answered in this work are "What is the minimum floor space for the ground floor of a one-family house, while maintaining accessibility according to Swedish demands?", "How can room functions be arrange for a one-family house in three floors with maintained housing qualities?", "How can a one-family house be designed to meet the future EU energy strategy towards 2020 concerning energy performance of buildings? ". The goal of this work is to design a one-family house in three floors with a minimum floor space on the entrance floor, which meet the future EU energy strategy towards 2020.   A literature study was conducted to investigate the impact of compact living on the living quality and energy efficient building design. In a case study of three buildings, housing in several floors was investigated. The design of a future onefamily house was conducted in a sketch work and finally the building was calculated to fulfill the current specification for a Zero-energy building.   A space-efficient plan design is accomplished by overlap the service areas, efficient disposition of room functions and by shared communication areas. The design of the entrance floor resulted in a gross internal area of 51,4 m2. The building is designed to meet the requirement of accessibility according to BBR and SIS.   Room functions which are represented on the entrance floor are kitchen, bathroom, separable bed space and space for sitting, dining, laundry and storage. Plan 2 consists of a large living room which is connected to the social functions on the entrance floor. The private floor of the building is plan 3 which consist of two of the building's three bedrooms.   The building is designed to meet the future EU energy strategy towards 2020. The building is a Zero-energy building due to the energy efficient design and the selfproduction of electricity from solar cells.   Our conclusion is that the relationship, disposition, communication and the separate placement of private and social spaces is essential to reduce the living space and to maintain good housing quality.

Examining methods for controlling the electricity demand in Kuwait was the main objective and motivation of this researchp roject. The extensiveu se of air-conditioning for indoor cooling in office and large commercial buildings in Kuwait and the Gulf States represents a major part of the power and electricity consumption in such countries. The rising electricity generation cost and growing rates of consumption continuously demand the construction new power plants. Devising and enforcing Demand-SideM anagemen(t DSM) in the form of energye fficient operations trategies was the response of this research project to provide a means to rectify this situation using the demand-side management technique known as demand levelling or load shifting. State of the art demand-sidem anagementte chniquesh ave been examined through the developmenot f a model basedp redictive control optimisations trategyf or an integrateda ndm odulara pproachto the provisiono f ice thermals torage. To evaluate the potential of ice-storage assisted air-conditioning systems in flattening the demand curve at peak times during the summer months in Kuwait, a model of a Heating, Ventilation, and Air-conditioning (HVAC) plant was developed in Matlab. The model engaged the use of model based predictive control (MPQ) as an optimisation tool for the plant as a whole. The model with MPC was developed to chose and decide on which control strategy to operate the integrated ice-storage HVAC plant. The model succeeded in optimising the operation of the plant and introduced encouraging improvement of the performance of the system as a whole. The concept of the modular ice-storage system was introduced through a control zoning strategy based on zonal orientation. It is believed that such strategy could lead to the modularisation of ice-storage systems. Additionally, the model was examined and tested in relation to load flattening and demonstrated promising enhancement in the shape of the load curve and demonstrated flattened demand curves through the employed strategy. When compared with measured data from existing buildings, the model showed potential for the techniques utilised to improve the load factor for office buildings.

The aim of this work is to make some investigations concerning duality for multiobjective optimization problems. In order to do this we study first the duality for scalar optimization problems by using the conjugacy approach. This allows us to attach three different dual problems to a primal one. We examine the relations between the optimal objective values of the duals and verify, under some appropriate assumptions, the existence of strong duality. Closely related to the strong duality we derive the optimality conditions for each of these three duals. By means of these considerations, we study the duality for two vector optimization problems, namely, a convex multiobjective problem with cone inequality constraints and a special fractional programming problem with linear inequality constraints. To each of these vector problems we associate a scalar primal and study the duality for it. The structure of both scalar duals give us an idea about how to construct a multiobjective dual. The existence of weak and strong duality is also shown. We conclude our investigations by making an analysis over different duality concepts in multiobjective optimization. To a general multiobjective problem with cone inequality constraints we introduce other six different duals for which we prove weak as well as strong duality assertions. Afterwards, we derive some inclusion results for the image sets and, respectively, for the maximal elements sets of the image sets of these problems. Moreover, we show under which conditions they become identical. A general scheme containing the relations between the six multiobjective duals and some other duals mentioned in the literature is derived. / Das Ziel dieser Arbeit ist die Durchführung einiger Untersuchungen bezüglich der Dualität für Mehrzieloptimierungsaufgaben. Zu diesem Zweck wird als erstes mit Hilfe des so genannten konjugierten Verfahrens die Dualität für skalare Optimierungsaufgaben untersucht. Das erlaubt uns zu einer primalen Aufgabe drei unterschiedliche duale Aufgaben zuzuordnen. Wir betrachten die Beziehungen zwischen den optimalen Zielfunktionswerten der drei Dualaufgaben und untersuchen die Existenz der starken Dualität unter naheliegenden Annahmen. Im Zusammenhang mit der starken Dualität leiten wir für jede dieser Dualaufgaben die Optimalitätsbedingungen her. Die obengenannten Ergebnisse werden beim Studium der Dualität für zwei Vektoroptimierungsaufgaben angewandt, und zwar für die konvexe Mehrzieloptimierungsaufgabe mit Kegel-Ungleichungen als Nebenbedingungen und für eine spezielle Quotientenoptimierungsaufgabe mit linearen Ungleichungen als Nebenbedingungen. Wir assoziieren zu jeder dieser vektoriellen Aufgaben eine skalare Aufgabe für welche die Dualität betrachtet wird. Die Formulierung der beiden skalaren Dualaufgaben führt uns zu der Konstruktion der Mehrzieloptimierungsaufgabe. Die Existenz von schwacher und starker Dualität wird bewiesen. Wir schliessen unsere Untersuchungen ab, indem wir eine Analyse von verschiedenen Dualitätskonzepten in der Mehrzieloptimierung durchführen. Zu einer allgemeinen Mehrzieloptimierungsaufgabe mit Kegel-Ungleichungen als Nebenbedingungen werden sechs verschiedene Dualaufgaben eingeführt, für die sowohl schwache als auch starke Dualitätsaussagen gezeigt werden. Danach leiten wir verschiedene Beziehungen zwischen den Bildmengen, bzw., zwischen den Mengen der maximalen Elemente dieser Bildmengen der sechs Dualaufgaben her. Dazu zeigen wir unter welchen Bedingungen werden diese Mengen identisch. Ein allgemeines Schema das die Beziehungen zwischen den sechs dualen Mehrzieloptimierungsaufgaben und andere Dualaufgaben aus der Literatur enthält, wird dargestellt.

The goal of this work is to present a conjugate duality treatment of composed programming as well as to give an overview of some recent developments in both scalar and multiobjective optimization. In order to do this, first we study a single-objective optimization problem, in which the objective function as well as the constraints are given by composed functions. By means of the conjugacy approach based on the perturbation theory, we provide different kinds of dual problems to it and examine the relations between the optimal objective values of the duals. Given some additional assumptions, we verify the equality between the optimal objective values of the duals and strong duality between the primal and the dual problems, respectively. Having proved the strong duality, we derive the optimality conditions for each of these duals. As special cases of the original problem, we study the duality for the classical optimization problem with inequality constraints and the optimization problem without constraints. The second part of this work is devoted to location analysis. Considering first the location model with monotonic gauges, it turns out that the same conjugate duality principle can be used also for solving this kind of problems. Taking in the objective function instead of the monotonic gauges several norms, investigations concerning duality for different location problems are made. We finish our investigations with the study of composed multiobjective optimization problems. In doing like this, first we scalarize this problem and study the scalarized one by using the conjugacy approach developed before. The optimality conditions which we obtain in this case allow us to construct a multiobjective dual problem to the primal one. Additionally the weak and strong duality are proved. In conclusion, some special cases of the composed multiobjective optimization problem are considered. Once the general problem has been treated, particularizing the results, we construct a multiobjective dual for each of them and verify the weak and strong dualities. / In dieser Arbeit wird, anhand der sogenannten konjugierten Dualitätstheorie, ein allgemeines Dualitätsverfahren für die Untersuchung verschiedener Optimierungsaufgaben dargestellt. Um dieses Ziel zu erreichen wird zuerst eine allgemeine Optimierungsaufgabe betrachtet, wobei sowohl die Zielfunktion als auch die Nebenbedingungen zusammengesetzte Funktionen sind. Mit Hilfe der konjugierten Dualitätstheorie, die auf der sogenannten Störungstheorie basiert, werden für die primale Aufgabe drei verschiedene duale Aufgaben konstruiert und weiterhin die Beziehungen zwischen deren optimalen Zielfunktionswerten untersucht. Unter geeigneten Konvexitäts- und Monotonievoraussetzungen wird die Gleichheit dieser optimalen Zielfunktionswerte und zusätzlich die Existenz der starken Dualität zwischen der primalen und den entsprechenden dualen Aufgaben bewiesen. In Zusammenhang mit der starken Dualität werden Optimalitätsbedingungen hergeleitet. Die Ergebnisse werden abgerundet durch die Betrachtung zweier Spezialfälle, nämlich die klassische restringierte bzw. unrestringierte Optimierungsaufgabe, für welche sich die aus der Literatur bekannten Dualitätsergebnisse ergeben. Der zweite Teil der Arbeit ist der Dualität bei Standortproblemen gewidmet. Dazu wird ein sehr allgemeines Standortproblem mit konvexer zusammengesetzter Zielfunktion in Form eines Gauges formuliert, für das die entsprechenden Dualitätsaussagen abgeleitet werden. Als Spezialfälle werden Optimierungsaufgaben mit monotonen Normen betrachtet. Insbesondere lassen sich Dualitätsaussagen und Optimalitätsbedingungen für das klassische Weber und Minmax Standortproblem mit Gauges als Zielfunktion herleiten. Das letzte Kapitel verallgemeinert die Dualitätsaussagen, die im zweiten Kapitel erhalten wurden, auf multikriterielle Optimierungsprobleme. Mit Hilfe geeigneter Skalarisierungen betrachten wir zuerst ein zu der multikriteriellen Optimierungsaufgabe zugeordnetes skalares Problem. Anhand der in diesem Fall erhaltenen Optimalitätsbedingungen formulieren wir das multikriterielle Dualproblem. Weiterhin beweisen wir die schwache und, unter bestimmten Annahmen, die starke Dualität. Durch Spezialisierung der Zielfunktionen bzw. Nebenbedingungen resultieren die klassischen konvexen Mehrzielprobleme mit Ungleichungs- und Mengenrestriktionen. Als weitere Anwendungen werden vektorielle Standortprobleme betrachtet, zu denen wir entsprechende duale Aufgaben formulieren.

Different attempts have been made to facilitate successful operation of Wastewater Pumping (WWP) system. The WWP units which are already existed in different parts of the world have been studied to identify its success, failure and different parameters associated with its suboptimal performance. The performance of WWP depends on three parameters namely pump, hydraulics, control system and pump station. These parameters are interdependent and must be carefully matched to achieve efficient WWP system. Nowadays the scenario has changed where organizations has started looking increasingly at the total cost of ownership, another way of saying Life Cycle Cost Analysis (LCCA) and recognizing the need to get most out of their equipment purchase. The master thesis includes theory part which describes the different parameters associated with WWP unit especially focusing on Xylems WWP system. This thesis is an attempt to help companies to know how LCCA could be productive management tool in order to minimize maintenance cost and maximize energy efficiency The study reported in this thesis work has been conducted to shed light over the use of Life Cycle Cost Analysis in WWP system. The current study tries to suggest and assess an adopted approach to ensure successful and efficient operation of WWP system with lowering energy demand and decrease in maintenance cost. Initial cost, Maintenance cost and Energy costs are important issues in the operation of WWP system since they are responsible for total cost over time. Therefore, description of each cost, formulas necessary for LCC calculations, data and survey structure, material and energy flow has been described. This work also aims to provide an extensive literature review, different survey and data collection techniques, analysis of collected data, statistical modelling, customer interaction by questionnaires and an interview with experts were used. LCC calculations were used to support the design and selection of most cost-efficient WWP system. Therefore, the given thesis work is an attempt to achieve better functional performance, improve existing design principles associated with WWP System, contribution to asses economic viability, support decision making to enhance operational quality to achieve efficient and successful WWP system.

I och med pensionsreformen vid sekelskiftet lades ett större ansvar på den individuelle pensionsspararen då man nu själv ska besluta hur en del av den allmänna pensionen ska placeras. Syftet med denna uppsats är att analysera huruvida det hade varit möjligt för en pensionssparare att uppnå en högre riskjusterad avkastning för sin premiepension genom att göra ett aktivt val i form av en egen sammansatt portfölj, än att låta staten förvalta pensionen i förvalsalternativet AP7 Såfa. Analysen är baserad på Harry Markowitz etablerade moderna portföljteori där han uppmärksammade hur sparare genom diversifiering kan reducera risken i sin placering genom att välja tillgångar som inte fullt samvarierar. Genom användning av tillgänglig data för tidsperioden 2000 – 2014 över de fonder som finns valbara i PPM-systemet har vi beräknat de optimala portföljer med samma risknivå som förvalsalternativet. Därefter har dessa jämförts med försvarsalternativet med avseende på risk och avkastning. Dessutom har tre teoretiska portföljer satts samman över en period på tio år, som placerats som dessa optimala portföljer och omallokerats efter Markowitz rekommendation att se över sitt sparande en gång om året. Analysen visar att det har gått att uppnå en högre riskjusterad avkastning genom att själv göra ett aktivt val av portfölj i sitt sparande. Problemet ligger i att det är svårt att identifiera dessa portföljer i förtid. De tre teoretiska portföljerna har samtliga presterat väsentligt mycket sämre än vad förvalsalternativet har gjort under samma tidsperiod. Resultatet visar att förvalsalternativet inte är fullt riskjusterat, man har alltså inte fullt fått betalt för den risk man tagit i sitt sparande. Vi drar ändå slutsatsen att förvalsalternativet är ett fullgott alternativ. / The Swedish premium pension reform at the turn of the century resulted in a greater responsibility for the individual saver. The decision concerning how the premium pension should be invested now lies with the investor. The purpose of this thesis is to analyze whether it had been profitable for a saver to achieve a higher risk-adjusted return for its premium pension money contributions by making an active choice by a self-composed portfolio, rather than to allow the State to invest the capital in the Seventh AP Fund (AP7 Såfa) which is the default option. The analysis is based on Harry Markowitz’s established Modern Portfolio Theory by which he drew attention to how investors through diversification can reduce risk in its investment by choosing assets that are not fully correlated. By using the available data of the funds that were selectable in the Swedish Premium Pension system by the time period 2000 – 2014, we have calculated the optimized portfolios with the same risk level as the default option. Subsequently, a comparison of these optimized portfolios and the default option are made in terms of risk and return. Furthermore, three theoretical portfolios are put together over a period of ten years and are invested as these optimized portfolios and reallocated after Markowitz's recommendation to review their savings once a year. The analysis shows that it has been possible to achieve higher risk-adjusted returns by making an active choice of portfolio. The problem though is that it is difficult to identify these portfolios in advance. The three theoretical portfolios have all generated a lower return than the default option did during the same period. The result shows that the default option is not fully risk-adjusted. Nonetheless, we conclude that the default fund is a good alternative.

Doctor of Philosophy / Department of Agricultural Economics / Jeffrey M. Peterson / The High Plains aquifer is a primary source of irrigation in western Kansas. Since World War II, producers increased irrigation and the irrigated acreage with the widespread adoption of newer irrigation technologies, causing a reduction in the saturated thickness of the High Plains aquifer. In an effort to conserve water and reduce further decline of the aquifer, the state of Kansas administered cost-share programs to producers who upgraded to an efficient irrigation system. But evidence suggests that the efforts to reduce water consumption have been undermined by producers, who under certain conditions have increased irrigation and irrigated acreage of high-valued and water-intensive crops. The state of Kansas is in a quandary to reduce water consumption and stabilize the saturated thickness of the aquifer while maintaining the economic viability of irrigated agriculture. A producer is faced with the choice of crop, irrigation timing and irrigation technology at the start of the season. This research identifies the conditions for risk-efficient crop choices and estimates the effect of an irrigation technology upgrade on the aquifer. Simulation models based on data from Tribune, Kansas were executed under various scenarios, varying by crop (corn or sorghum), irrigation system (conventional center-pivot or center-pivot with drop nozzles) and well capacity (190, 285 or 570 gallons per minute). Each well capacity was associated with a pre-season soil moisture level (0.40, 0.60 or 0.80 of field capacity). Each scenario was simulated over weather data observed during the 36-year period (1971-2006). Results indicate that producers with slower wells could maximize their net returns while conserving water by choosing less water-intensive crops like sorghum, while irrigating with a conventional center-pivot irrigation system. Producers with faster wells could maximize net returns by choosing water-intensive crops like corn and irrigate with the more efficient center-pivot with drop nozzle irrigation system. In order to reduce groundwater consumption and maintain the saturated thickness of the aquifer, water policies should internalize the interests of all stakeholders and be a combination of irrigation technology, economic factors, hydrological conditions, agronomic practices, conservation practices and local dynamics of the region.