This thesis focuses on one certain process of cooperation of two cooperating robots operating an automatic measuring station. In this process, articles are handled by two industrial robots KUKA KR6/2. The objective of this thesis was to develop, construct and put into operation a measuring station and the associated workstation. For this purpose the appropriate programs controlling the robots and the measuring stations have been developed. The reader will be acquainted with the design of the workstation and its putting into operation. In addition, the thesis describes in detail the control of the robots and their program part. At the conclusion of the paper, opportunities of optimization of the power period are addressed in brief.

Improved industrial energy efficiency is viewed as an important means in the reduction of CO2 emissions and climate change mitigation. Various energy efficiency measures for improving energy efficiency exists, but even evaluated as cost-effective, there seems to be a difference between the energy efficiency measures that theoretically could be undertaken and which measures that actually are realised. On the other hand, industrial energy efficiency measures might yield extra effects, denoted as non-energy benefits, beyond the actual energy savings or energy cost savings. Based on interviews and a questionnaire, results showed that the Swedish industrial firms studied had observed various non-energy benefits. However, few of the non-energy benefits observed were translated into monetary values and included in investment calculations. Results indicated that this non-inclusion could be explained by lack on information on how to measure and monetise the benefits, but even if not translated into monetary values, some of the non-energy benefits were sometimes used qualitatively in investment decisions. The utilisation of the benefits seemed to depend on the type and the level of quantifiability among the perceived benefits. This thesis has also explored energy efficiency measures and non-energy benefits for a specific industrial energy-using process – compressed air. A literature review on energy efficiency in relation to compressed air systems revealed a large variation in which measures that could be undertaken to improve energy efficiency. However, few publications applied a comprehensive perspective including the entire compressed air system. Few non-energy benefits of specific energy efficiency measures for compressed air systems were identified, but the study provided insights into how non-energy benefits should be studied. This thesis suggests that energy efficiency and non-energy benefits in compressed air systems should be studied on specific measure level to enable the observation of their effects. However, the studies also addressed the importance of having a systems perspective; the whole system should be regarded to understand the effects of energy efficiency measures and related non-energy benefits.

<p>Compressed  air  is  a  powerful  source  of  stored  energy  and  is  used  in  a  variety  of  applications varying from painting to pressing, making it a versatile tool for manufacturers.  Due to the high cost and energy consumption associated with producing compressed air and it’s use within industrial manufacturing, it is often referred to as a fourth utility behind electricity, natural gas, and water.  This is the reason why air compressors and associated equipment are often the focus for improvements in the eyes of manufacturing plant managers.</p> <p><br></p> <p>As compressed air can be used in multiple ways, the methods used to extract and transfer the energy from this source vary as well.  Compressed air can flow through different types of piping, such as aluminum, Polyvinyl Chloride (PVC), rubber, etc.  with varying hydraulic diameters, and through different fittings such as 90-degree elbows, T-junctions, valves, etc.which can cause one of the major concerns related to managing the energy consumption of an air compressor, and that is the waste of air through leaks.</p> <p>Air leaks make up a considerable portion of the energy that is wasted in a compressed air system,  as they cause a multitude of problems that the compressor will have to makeup  for  to  maintain  the  steady  operation  of  the  pneumatic  devices  on  the  manufacturing floor that rely on compressed air for their application.  When air leaks are formed within the compressed air piping network,  they act as continuous consumers and cause not only the siphoning off of said compressed air, put also reduce the pressure that is needed within the  pipes.   The  air  compressors  will  have  to  work  harder  to  compensate  for  the  losses  in the pressure and the amount of air itself, causing an over consumption of energy and power.Overworking the air compressor also causes the internal equipment to be stretched beyond its capabilities, especially if they are already running at full loads, reducing their total lifespans considerably.  In addition, if there are multiple leaks close to the pneumatic devices on the manufacturing floor, the immediate loss in pressure and air can cause the devices to operate inefficiently and thus cause a reduction in production.  This will all cumulatively impact the manufacturer considerably when it comes to energy consumption and profits.</p> <p>There are multiple methods of air leak detection and accounting that currently exist so as  to  understand  their  impact  on  the  compressed  air  systems.   The  methods  are  usually conducted when the air compressors are running but during the time when there is no, orminimal, active consumption of the air by the pneumatic devices on the manufacturing floor.This time period is usually called non-production hours and generally occur during breaksor  between  employee  shift  changes.   This  time  is  specifically  chosen  so  that  the  only  air consumption within the piping is that of the leaks and thus, the majority of the energy and power consumed during this time is noted to be used to feed the air leaks.  The collected data is then used to extrapolate and calculate the energy and power consumed by these leaks for the rest of the year.  There are, however, a few problems that arise when using such a method to understand the effects of the leaks in the system throughout the year.  One of the issues is that it is assumed that the air and pressure lost through the found leaks areconstant even during the production hours i.e.  the hours that there is active air consumptionby the pneumatic devices on the floor, which may not be the case due to the increased airflow rates and varying pressure within the line which can cause an increase in the amount of air lost through the same orifices that was initially detected.  Another challenge that arises with using only the data collected during a single non-production time period is that theremay be additional air leaks that may be created later on,  and the energy and power lostdue to the newer air leaks would remain unaccounted for.  As the initial estimates will not include the additional losses, the effects of the air leaks may be underestimated by the plant managers.  To combat said issues, a continuous method of air leak analyses will be required so as to monitor the air compressors’ efficiency in relation to the air leaks in real time.</p> <p>By studying a model that includes both the production, and non-production hours when accounting  for  the  leaks,  it  was  observed  that  there  was  a  50.33%  increase  in  the  energy losses, and a 82.90% increase in the demand losses that were estimated when the effects ofthe air leaks were observed continuously and in real time.  A real time monitoring system canprovide an in-depth understanding of the compressed air system and its efficiency.  Managing leaks within a compressed air system can be challenging especially when the amount of energy wasted through these leaks are unaccounted for.  The main goal of this research was to finda non intrusive way to calculate the amount of air as well as energy lost due to these leaks using time series pressure measurements.  Previous studies have shown a strong relationship between the pressure difference, and the use of air within pneumatic lines, this correlationalong with other factors has been exploited in this research to find a novel and viable methodof leak accounting to develop a Continuous Air Leak Monitoring (CALM) system.</p> <p><br></p>

Wildland fire services have successfully integrated compressed air foam systems (CAFS) into their fire suppression arsenal over the last few decades to effectively increase the firefighting ability of water. Many urban fire departments have done the same, but far more still rely on plain water to extinguish Class A fires. Many claims have been made about the advantages and disadvantages of firefighting foams, but only limited research has been conducted on the subject to date. Fire departments need more information, beyond that provided by foam suppliers and CAFS equipment manufacturers, to make an independent decision on whether or not to adopt the technology. This thesis is part of a larger project sponsored by the United States Department of Homeland Security Assistance to Firefighter Grant Program (grant ID: EMW-2010-FP-01369) to evaluate the capabilities and limitations of compressed air foam systems (CAFS) for use in structural firefighting applications. Large-scale tests comparing water and foam suppression, which includes aspirated foam and CAFS, in a variety of scenarios were performed to measure the ability of the hose streams to reduce the temperature of a hot gas layer within a structure. These temperature reductions were recorded with thermocouples and are analyzed to determine which suppression agent has a superior gas cooling ability.

This study investigates Compressed Air Energy Storage (CAES) application in the electrical power and transportation industries. Information concerning current CAES projects is presented. A thorough thermodynamic analysis of the CAES process is completed; including theoretical efficiency determination for several variants of the compression and expansion processes. Industry claimed efficiencies ranging from 26% to 82% are presented and explained. Isothermal and Isentropic efficiency baselines are developed. Energy density of compressed air on both a mass and volume basis is compared to other energy storage methods. Best expected efficiency of a hypothetical CAES system is determined to be 34% using currently achievable efficiencies and 63% considering 100% efficient compression and expansion. A .5 kW CAES system, built from commercial off the shelf components (COTS) to demonstrate the CAES concept, is documented and discussed. This system includes a LabView data acquisition system which was used to record all test results. LabView was also used to develop a complete test bed program that determined real time thermodynamic state properties, component efficiencies, mass flow rates, power outputs and several other performance characteristics of the demonstration system. The LabView program allowed real time efficiency and power optimization of the demonstration system. Results of demonstration system testing are thoroughly discussed. Total system efficiency was very poor; 3.6% electrical conversion efficiency, .040 refrigeration coefficient of performance (COP) and a 5.0% overall efficiency which considers both cooling and electrical storage properties. Several paths for possible future projects involving the demonstration system and CAES are presented.

Arbetet beskrivet i denna rapport har utförts på AstraZeneca AB:sproduktionsanläggning i Gärtuna, Södertälje. Företaget vill öka redundansen på sin tryckluftsanläggning för att höja driftsäkerheten i produktionen. I sin tillverkning av läkemedel används stora mängder tryckluft för bland annat produktionsprocesser. Vid haveri av till exempel en kompressor riskerar produktionen att bli stillastående tills dess att problemet åtgärdats eller att en hyrd kompressor har kopplats in. Produktionsbortfall är en av de största indirekta kostnaderna ett tillverkningsföretag kan råka ut för. Då AstraZeneca tillverkar läkemedel uppstår även konsekvenser för samhället då viktiga läkemedel inte når ut till kunden. Det är därför av stor vikt att de stöttande systemen, som till exempel tryckluftssystemet, designas med inbyggd redundans för att klara av haverier eller läckage. Målet med projektet har varit att föreslå en lösning för att sammankoppla ett mindre tryckluftssystem med det centrala systemet för att öka redundansen på anläggningen. Det mindre systemet förser produktionen i byggnad B833 med tryckluft. Systemets tryck i denna byggnad är för närvarande högre än trycket i det centrala systemet och kan därför inte kopplas samman. Det har genomförts försök att sänka trycket i B833, men tyvärr har det lägre trycket lett till att problem i produktionen uppstått. I projektets genomförande har orsaken till att problemen uppstår undersökts genom att kartlägga alla brukare av tryckluft i byggnaden, analysera produktions- och tryckluftsloggar samt kartläggning av rörsystemet och dess dimensioner. Teori har insamlats genom litteratursökning och intervjuer med personal från produktion och driftorganisation. Grundorsaksanalys har genomförts med verktygen Ishikawa och 5-varför metoden. Resultatet verifierades med en FTA, felträdsanalys. För att kunna sänka trycket i B833 till 6,5 bar krävs det att vissa ledningar ersätts med rör med större dimensioner. På vissa delar av rörnätet uppstår ett för högt tryckfall på grund av för små dimensioner. 6,5 bar vid kompressorn reduceras till 3,3 bar längst ut i systemet på plan 3, vid normalflöde. Många maskiner i byggnaden fungerar inte med ett sådant lågt tryck. Lösningen består av att byta ut 4 stycken rörledningar och öka dessa från 25, 20, 20, och 15 mm till 50, 40, 40 och 32 mm respektive. Dessa ledningar befinner sig både på plan 1, plan 3 och i schaktet mellan våningsplanen. Ökade dimensioner på dessa rör kommer att möjliggöra en trycksänkning i B833 och sammankopplingen med det centrala systemet kan driftsättas. Detta leder till ökad redundans och högre driftsäkerhet, både i B833 så väl som i hela anläggningen. / The project summarized in this report was executed at AstraZeneca’s production facilityin Gärtuna, Södertälje. The company wants to increase redundancy in their compressed air system in order to achieve higher operational reliability. In their manufacture of pharmaceuticals, large amounts of compressed air are used for, among other things, production processes. In case of a breakdown of, for example, a compressor, the production is at risk of becoming stagnant until the problem has been rectified or arental compressor has been connected to the system. Production loss is one of the largest indirect costs for a manufacturing company. And perhaps more importantly, medicines will not reach the customer in time. It is therefore of great importance that the supporting systems, such as the compressed air system, are designed with built-in redundancy to cope with breakdowns or leaks. The goal of the project has been to find a solution to connect a smaller compressed air system with the central system to increase the redundancy at the facility. The smaller system supplies the production in building B833 with compressed air. The pressure of the system in this building is currently higher than the pressure in the central system, and therefore they cannot be connected. Attempts have been made to reduce the pressure in B833, which has led to problems in the production. In this project, the cause of the problems that occur when pressure is reduced has been investigated by mapping all users of compressed air in the building, analyzing logs from production and compressed air systems, and mapping the pipe system and its dimensions. The theory necessary for solving the task has been gathered through a literature study as well as interviewing personnel from the production and the operating organization. Root cause analysis has been performed, using the tools Ishikawa and 5-why-method. The results were verified with a FTA, Fault tree analysis. To be able to decrease the pressure in B833 to 6,5 bar, it will require the distribution pipes to be replaced with pipes in larger dimensions. In some parts of the piping system, the pressure drop will be too high because of too small dimensions. 6,5 bar from the compressor is reduced to 3,3 bar at the far end of the system on floor level 3, while the consumption is at a normal level. Many of the machines will not work on that low level of pressure. The solution is to change the dimensions of four pipes from 25, 20, 20 and 15 mm to 50, 40, 40 and 32 mm respectively. The pipes considered are located at level 1, level 3 and in a shaft located between these levels. With larger dimensions, it will be possible to reduce the pressure, and this will enable the pipes that are connected to the central system to be taken into operation. This will lead to an increase in redundancy and reliability in B833 as well as the whole production site.

Energy consumption is one of the major concerns in the current environment, not only because of the limited availability of non-renewable fuels, but also due to the high cost and the pollution generated by energy production. In general, industries consume large quantities of electricity, fuels and other types of energy. Among the industries, the chemical industry is one of the highest energy consumers because of the nature of its processes. This fact makes the chemical industry one of the best candidates for the study and evaluation of different technologies to improve the efficiency of the energy use without affecting the productivity and quality of their processes and products. This thesis analyzes the energy consumption in the chemical industry and provides recommendations to increase the energy efficiency of the critical systems utilized in this industry. Different methods to reduce the energy losses during generation and transmission, the use of waste heat for improving energy efficiency, and several analysis tools to help in evaluating the potential energy and cost savings for each facility are also discussed in this thesis. Several case studies are reviewed to demonstrate the effectiveness of the energy savings recommendations and tools presented in this investigation.

The main purpose of this master’s thesis is description of the current technology of compressed air production in the grounds of Třinecké Železárny, a.s. (TZ). Compressed air for companies in the TZ area is manufactured and distributed by company Energetika Třinec, a.s. (ET). The part of the thesis is the preparation and execution of measurement including evaluation of specific energy consumption for production of compressed air by compressors of ET company. In conclusion there is proposed the possibility of substitution of compressors including the economic evaluation.

The objective of this PhD thesis is to create a Unit Commitment and Economic Dispatch (UCED) modelling tool that can used to simulate the deterministic performance of a power system with thermal and renewable generators and energy storage technologies. The model was formulated using mixed integer programing (MIP) on GAMS interface. A robust commercial solver by IBM (CPLEX) is used as solver. Emphasis on the development of the tool has been given on the following aspects. a) Technical impacts of Variable Renewable Energy (VRE) integration. The UCED model developed in this thesis is a high resolution short-term dispatch model. It captures the variability of VRE power on the intra-hour level. In addition the model considers a large number of important real world, system, unit and policy constraints. Detailed representation of a power system allows for a realistic estimation of maximum penetration levels of VRE and the related technical impacts like cycling of generators (part-loading and number of start-ups). b) CO2 emissions. High levels of VRE penetration can potentially increase consumption of fuel in thermal units per unit of electricity produced due to increased thermal cycling. The dispatch of units in the UCED model is based on minimizing system wide operational costs the most important of those being fuel, start-up costs and the cost of carbon. Fuel consumption is calculated using technical data from Input/Output curves of individual generators. The start-up cost is calculated based on times the generator units have been off and the energy requirement to bring the unit back to hot state. Thus dynamic changes on fuel consumption can be captured and reported. c) Technical solutions to facilitate VRE integration. VRE penetration can be facilitated if appropriate solutions are implemented. Energy storage is an effective way to reduce the impact of RE variability. The UCED model includes an integrated Mixed Integer Linear (MILP) compressed air energy storage (CAES) simulation sub-model. Unlike existing CAES models, the new “Thermo-Economic” (TE) CAES model developed in this thesis uses technical data from major CAES manufacturers to model the dynamic effect of cavern pressure on both the compression and expansion sides during CAES operation. More specifically the TE model takes into account that a) a compressor discharges at a pressure equal to the back-pressure developed in the cavern at each moment, b) the speed of charging can be regulated through inlet guide vanes; higher charging speed can take place at the expense of additional power consumption, c) the maximum power output during expansion can be limited by the levels of cavern pressure; there is a threshold pressure level below which the maximum output decreases linearly with pressure. Since it uses actual power curves to simulate CAES operation, the TE model can be assumed to be more accurate than conventional Fixed Parameter (FP) models that don’t model dynamic effects of cavern pressure on CAES operation. The TE model in this thesis is compared with conventional FP models using historical market prices from the Irish electricity market. The comparison was based on the ability of a CAES unit to arbitrage energy for making profit in the Irish electricity market. More specifically a “Base” scenario was created that included the operation of a 270MW CAES unit with technical characteristics obtained from a major CAES manufacturer and assumed discharge time of 13hr. Various sensitivities on discharge time, natural gas prices and system marginal prices (SMPs) were modeled. An additional scenario was created to show the benefit on CAES profitability if the unit participated in both the energy and ancillary services markets. All scenarios were modeled using both the TE and FP CAES models. The results showed that the most realistic TE model returns around 15% less profitability across more scenarios. The reduction in profitability grows to around 30% when the cavern volume (discharge time) is reduced to half (6 hours). The latter is related to the sensitivity of the TE model on cavern pressure that is being built faster when the volume is reduced. A CAES unit won’t get a positive net present value (NPV) in Ireland under any scenario unless SMPs are greatly increased. Thus, it was shown that that existing FP CAES models overestimate CAES profitability. More accurate models need to be used to estimate CAES profitability in deregulated markets. Additionally, it might deem necessary to create additional markets for energy storage units and increase the possible revenue sources and magnitude to facilitate an increase of storage capacity worldwide. The second step of analysis involved the integration of the CAES and UCED models. The UCED model developed in this thesis was validated and applied using data from the Irish grid, a power system with more than 50 thermal generators. A vast of existent data was used to create a mathematical model of the Irish system. Such data include technical specifications and variables of thermal generators, maintenance schedules and historical solar, wind and demand data. The validation exercise was deemed successful since the UCED model simulated utilization factors of 45 out of 52 generators with an absolute difference between modeled and actual results on utilization factors of less than 6% (the absolute differences are called Delta in this thesis). In addition the results of validation exercise were compared with the results of a similar exercise where PLEXOS was the modelling tool and it was found that the results of the two models were similar for the vast majority of generators. More specifically, the PLEXOS model results showed higher deltas for the coal-fired generators compared to the UCED model. On the other hand the UCED model, reported higher delta values for peat-fired generators. The results of the PLEXOS model were slightly better for the gas-fired generators while both models reported deltas nearly zero for all oil and distillate-fired generators. Finally the model was applied to study the benefits of energy storage in Ireland in 2020 when wind penetration is expected to reach 37% of total demand. The analysis involved the development of two groups of 3 scenarios each. In the first group the main scenario also called the “Reference” was used to simulate the short-term unit (30 min step) commitment within the Irish system without storage. The results of the reference scenario were compared with two additional scenarios that assumed the existence of one 270MW CAES unit in Northern Ireland by 2020 (again the first scenario involved the TE and the second the FP CAES model). The results showed –when using the TE model- that the inclusion of one 270MW CAES unit in AI can help reduce wind curtailment by 88GWh, CO2 emissions by 150,000 tonnes and system costs by € 6 million per year. If an FP model had been used instead the reductions would be: wind curtailment by 108GWh, CO2 emissions by 270,000 tonnes and annual system costs by €13 million. Two main conclusions can be obtained from the specific set of results. The first conclusion is that storage units have a financial benefit over the whole system. Thus, when a CAES unit operates to minimize the costs of the whole system can incur substantially more benefits compared to if the CAES unit operated to maximize the individual unit’s profits as in the case presented earlier. The benefits of storage over the whole system should be accounted to make policy decisions and create incentives for investors to increase energy storage capacity in national grids. The second important conclusion is that existing CAES FP models overestimate the ability of a CAES unit to facilitate VRE penetration. More accurate TE models should be used to assess a unit’s capability to increase system flexibility. A second group of scenarios was created to simulate the benefit of CAES at even higher VRE penetration levels. In the second group the “Reference” scenario again, assumed no storage however, wind production was increased by 25%. Again the “Reference” was compared with two additional scenarios that assumed integration of 3x270MW=810MW of storage capacity in AI (one scenario used the TE model and the other the FP). The results for the TE model show that each of the 3 CAES units reduces wind curtailment by 188,000MWh, total system costs by €29 million and CO2 emissions by 180,000 tonnes. The same reductions for the FP model are 217,000MWh of wind curtailment, €25.6 million on total system costs and 180,000 tonnes of CO2. Thus, the results of the second group of scenarios show that as the installed capacity of both CAES and wind increases in Ireland a) the system-wide benefits of CAES increase and b) the differences on results between the TE and FP models become much smaller.

Energy shortage, escalation of energy cost and climate change have led to an increased focus on energy conservation worldwide. In order to curb the increase in electricity demand, Eskom has introduced demand-side management (DSM) to improve energy efficiency and to shift peak-time load to off-peak periods in order to postpone additional capacity requirements. In the past, several mine DSM projects have been implemented without the use of system simulations as part of the analysis of project planning. Many of these projects are characterised by contractual energy saving targets that have not been met, projects that are delayed, potential energy savings projects that have been overlooked and additional savings that have not realised. This study demonstrates the potential of simulations to plan new and correct implemented DSM solutions. This is done by allowing analysis of energy consumption in complex technical systems and quantification of the savings potential of DSM interventions to inform design changes in order to attain energy savings. In applying simulations to a well-instrumented compressed air system, it was possible to compare the theoretical and measured values for system parameters. The simulation was fine-tuned for low-pressure operation (with the system operating well within design constraints) by incorporating estimated flow losses. By simulating high-pressure operation in which the system operates closer to design limits, the constraints that were experienced, were revealed. This application exemplifies the approach that has been adopted in the case studies to follow. The value of the use of simulation models for mine DSM projects Simulations that have been applied to four case studies demonstrate the use in improving existing DSM projects as well as in planning new DSM projects. Two case studies demonstrate the use of simulations in rectifying problems that have been encountered during the implementation of existing mine DSM projects. Simulations have been employed to propose corrections to these project implementations; this demonstrates significant value for the customer. In two additional case studies, the value of simulation models is demonstrated where simulations have been developed prior to the implementation of DSM projects. It demonstrates that projects can be implemented with less effort, in a shorter time span and at a reduced cost (both capital and man-hours) by using simulations in the planning phases of DSM projects. / Thesis (MIng (Mechanical Engineering))--North-West University, Potchefstroom Campus, 2013.