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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The modelling of energy efficient drying for DSM

Gilmour, James Ewan January 1999 (has links)
This thesis investigates the modelling of drying processes for the promotion of market-led Demand Side Management (DSM) as applied to the UK Public Electricity Suppliers. A review of DSM in the electricity supply industry is provided, together with a discussion of the relevant drivers supporting market-led DSM and energy services (ES). The potential opportunities for ES in a fully deregulated energy market are outlined. It is suggested that targeted industrial sector energy efficiency schemes offer significant opportunity for long term customer and supplier benefit. On a process level, industrial drying is highlighted as offering significant scope for the application of energy services. Drying is an energy-intensive process used widely throughout industry. The results of an energy survey suggest that 17.7 per cent of total UK industrial energy use derives from drying processes. Comparison with published work indicates that energy use for drying shows an increasing trend against a background of reducing overall industrial energy use. Airless drying is highlighted as offering potential energy saving and production benefits to industry. To this end, a comprehensive review of the novel airless drying technology and its background theory is made. Advantages and disadvantages of airless operation are defined and the limited market penetration of airless drying is identified, as are the key opportunities for energy saving. Limited literature has been found which details the modelling of energy use for airless drying. A review of drying theory and previous modelling work is made in an attempt to model energy consumption for drying processes. The history of drying models is presented as well as a discussion of the different approaches taken and their relative merits. The viability of deriving energy use from empirical drying data is examined. Adaptive neuro fuzzy inference systems (ANFIS) are successfully applied to the modelling of drying rates for 3 drying technologies, namely convective air, heat pump and airless drying. The ANFIS systems are then integrated into a novel energy services model for the prediction of relative drying times, energy cost and atmospheric carbon dioxide emission levels. The author believes that this work constitutes the first to use fuzzy systems for the modelling of drying performance as an energy services approach to DSM. To gain an insight into the 'real world' use of energy for drying, this thesis presents a unique first-order energy audit of every ceramic sanitaryware manufacturing site in the UK. Previously unknown patterns of energy use are highlighted. Supplementary comments on the timing and use of drying systems are also made. The limitations of such large scope energy surveys are discussed.
2

A performance-centered maintenance strategy for industrial DSM projects / Hendrik Johannes Groenewald

Groenewald, Hendrik Johannes January 2015 (has links)
South Africa’s electricity supply is under pressure because of inadequate capacity expansion in the early 2000s. One of the initiatives funded by Eskom to alleviate the pressure on the national electricity grid was an aggressive demand-side management (DSM) programme that commenced in 2004. A positive outcome of the DSM programme was that the industrial sector in South Africa benefited from the implementation of a relatively large number of DSM projects. These DSM projects reduced the electricity costs of industrial clients and reduced the demand on the national electricity grid. Unfortunately, the performance of industrial DSM projects deteriorates without proper maintenance. This results in wasted savings opportunities that are costly to industrial clients and Eskom. The purpose of this study was therefore to develop a maintenance strategy that could be applied, firstly, to reverse the deterioration of DSM project performance and, secondly, to sustain and to improve DSM project performance. The focus of the maintenance strategy was to obtain maximum project performance that translated to maximum electricity cost savings for the client. A new performance-centered maintenance (PCM) strategy was developed and proven through practical experience in maintaining industrial DSM projects over a period of more than 60 months. The first part of the PCM strategy consisted of developing a new strategy for the outsourcing of DSM project maintenance to energy services companies (ESCOs) on the company group level of the client. The strategy served as a guideline for both ESCOs and industrial clients to implement and manage a group-level DSM maintenance agreement successfully. The second part of the PCM strategy consisted of a simplified method that was developed to identify DSM projects where applying a PCM strategy would increase or sustain electricity cost savings. The third part of the PCM strategy consisted of practical maintenance guidelines that were developed to ensure maximum project performance. It was based on the plan-do-check-act cycle for continuous improvement with an emphasis on the monitoring of DSM project performance. The last part of the PCM strategy consisted of various alternative key performance indicators that should be monitored to ensure maximum sustainable DSM project performance. The PCM strategy was evaluated by implementing it on ten different DSM projects. The results showed that applying a PCM strategy resulted in an average increase of 64.4% in the electricity cost savings generated by these projects. The average implementation cost of the PCM strategy was 6% of the total benefit generated through it. This indicated that implementing the PCM strategy was a cost-effective manner to ensure that maximum performance of DSM projects was maintained sustainably. / PhD (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015
3

The cost-effectiveness of comprehensive system control on a mine compressed air network / Stephanus Nicolaas van der Linde

Van der Linde, Stephanus Nicolaas January 2014 (has links)
Compressed air leakage accounts for up to 42% of electrical energy loss on a typical mine compressed air system. By using underground control valves it is possible to reduce the amount of air leakage. Underground valve control was successfully implemented in a South African mine. The project implementation and achieved results are documented in this study. The implementation of underground control valves initially requires a large capital investment. In this study the electrical and financial savings realised by underground valve control and surface valve control were calculated. The payback periods for each control strategy were determined and compared. It was determined that underground valve control can realise up to 40% higher electrical savings than surface control. Depending on the size of the mine and due to the large initial investment, the payback period for an underground valve control system can be up to six times longer than that of a surface control system. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
4

A performance-centered maintenance strategy for industrial DSM projects / Hendrik Johannes Groenewald

Groenewald, Hendrik Johannes January 2015 (has links)
South Africa’s electricity supply is under pressure because of inadequate capacity expansion in the early 2000s. One of the initiatives funded by Eskom to alleviate the pressure on the national electricity grid was an aggressive demand-side management (DSM) programme that commenced in 2004. A positive outcome of the DSM programme was that the industrial sector in South Africa benefited from the implementation of a relatively large number of DSM projects. These DSM projects reduced the electricity costs of industrial clients and reduced the demand on the national electricity grid. Unfortunately, the performance of industrial DSM projects deteriorates without proper maintenance. This results in wasted savings opportunities that are costly to industrial clients and Eskom. The purpose of this study was therefore to develop a maintenance strategy that could be applied, firstly, to reverse the deterioration of DSM project performance and, secondly, to sustain and to improve DSM project performance. The focus of the maintenance strategy was to obtain maximum project performance that translated to maximum electricity cost savings for the client. A new performance-centered maintenance (PCM) strategy was developed and proven through practical experience in maintaining industrial DSM projects over a period of more than 60 months. The first part of the PCM strategy consisted of developing a new strategy for the outsourcing of DSM project maintenance to energy services companies (ESCOs) on the company group level of the client. The strategy served as a guideline for both ESCOs and industrial clients to implement and manage a group-level DSM maintenance agreement successfully. The second part of the PCM strategy consisted of a simplified method that was developed to identify DSM projects where applying a PCM strategy would increase or sustain electricity cost savings. The third part of the PCM strategy consisted of practical maintenance guidelines that were developed to ensure maximum project performance. It was based on the plan-do-check-act cycle for continuous improvement with an emphasis on the monitoring of DSM project performance. The last part of the PCM strategy consisted of various alternative key performance indicators that should be monitored to ensure maximum sustainable DSM project performance. The PCM strategy was evaluated by implementing it on ten different DSM projects. The results showed that applying a PCM strategy resulted in an average increase of 64.4% in the electricity cost savings generated by these projects. The average implementation cost of the PCM strategy was 6% of the total benefit generated through it. This indicated that implementing the PCM strategy was a cost-effective manner to ensure that maximum performance of DSM projects was maintained sustainably. / PhD (Computer and Electronic Engineering), North-West University, Potchefstroom Campus, 2015
5

The cost-effectiveness of comprehensive system control on a mine compressed air network / Stephanus Nicolaas van der Linde

Van der Linde, Stephanus Nicolaas January 2014 (has links)
Compressed air leakage accounts for up to 42% of electrical energy loss on a typical mine compressed air system. By using underground control valves it is possible to reduce the amount of air leakage. Underground valve control was successfully implemented in a South African mine. The project implementation and achieved results are documented in this study. The implementation of underground control valves initially requires a large capital investment. In this study the electrical and financial savings realised by underground valve control and surface valve control were calculated. The payback periods for each control strategy were determined and compared. It was determined that underground valve control can realise up to 40% higher electrical savings than surface control. Depending on the size of the mine and due to the large initial investment, the payback period for an underground valve control system can be up to six times longer than that of a surface control system. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
6

Domestic demand response to increase the value of wind power

Hamidi, Vandad January 2009 (has links)
This thesis describes a new method to evaluate the value of wind power combined with domestic demand response. The thesis gives a brief overview of current domestic demand management programmes, and highlights the demand response and its current application. Such technology has conventionally been used for different purposes, such as frequency regulation, and to minimize the spot electricity prices in the market. The aim is to show whether such technology may become useful to make the renewables, and in particular wind power more interesting for investors. An assessment framework based on generation scheduling is developed to quantify the value of wind power. A further important aspect of value of wind power is the impact of intermittency on overall reliability of the system. This necessitates increasing the spinning reserve level which will increase the production cost. The changes in the spinning reserve level has been investigated in this thesis and it has been shown that how different forecasting errors may change the overall value of a windfarm over its lifetime. One of the most important aspects of a system containing demand response, is the availability of demand response. A load modelling package is developed to show the potential for demand response in a real system from domestic sector. With every increasing the concerns with regard to future of generation mix in Britain, this work has proposed over 72 scenarios for the future of generation mix in Britain and the impact of demand response to increase the value of wind power in 2020 has been investigated. The assessment framework is enhanced by showing that how the value of wind power combined with domestic demand response may change by changes in emission price, and cost of demand response. This will show the degree of feasibility of such system in which demand response is treated like a commodity.
7

Impact of Elasticity in Domestic Appliances on Aggregate Residential Power Demands

Srikantha, Pirathayini 27 March 2013 (has links)
Power grids in today's developed societies are designed to meet consumer demands in a highly reliable manner. In order to guarantee reliability to consumers, the grid is required to be sized for infrequently occurring demand peaks. The cost of maintaining generation sources that make up the relatively unused capacity of the grid can be extremely high. In addition to high costs, environmental impacts of these sources are also of great concern. In order to serve highly fluctuating peak demands, energy sources such as coal, gas and bio-gas are commissioned by utilities. These sources have a high carbon footprint. In order to prevent wasting extensive amounts of money in maintaining infrequently used grid capacity and causing an adverse environmental impact, a comprehensive study on how elasticity of domestic appliances can be used to reduce the impact of these issues is made. A thorough analysis of appliances in four distinct regions is presented. Significant reduction of peak demands is shown quantitatively for all of the four regions. Based on these positive results, an elasticity based scheme that takes into account user discomfort is proposed for reducing monetary and environmental issues faced by today's utilities.
8

Impact of Elasticity in Domestic Appliances on Aggregate Residential Power Demands

Srikantha, Pirathayini 27 March 2013 (has links)
Power grids in today's developed societies are designed to meet consumer demands in a highly reliable manner. In order to guarantee reliability to consumers, the grid is required to be sized for infrequently occurring demand peaks. The cost of maintaining generation sources that make up the relatively unused capacity of the grid can be extremely high. In addition to high costs, environmental impacts of these sources are also of great concern. In order to serve highly fluctuating peak demands, energy sources such as coal, gas and bio-gas are commissioned by utilities. These sources have a high carbon footprint. In order to prevent wasting extensive amounts of money in maintaining infrequently used grid capacity and causing an adverse environmental impact, a comprehensive study on how elasticity of domestic appliances can be used to reduce the impact of these issues is made. A thorough analysis of appliances in four distinct regions is presented. Significant reduction of peak demands is shown quantitatively for all of the four regions. Based on these positive results, an elasticity based scheme that takes into account user discomfort is proposed for reducing monetary and environmental issues faced by today's utilities.
9

Power flexibility in a property : Independent Project in Electrical Engineering

Jawad, Alhassan, Hertzberg, Andreas, Sundman, Johan January 2022 (has links)
Sweden has since a few years back suffered from a bottleneck in the power transmission lines stemming from a lack of “space” on the grid that transports the power that is generated in the northern parts to the middle and southern parts of the country. A long-term solution would be to increase the grid's capacity by building more transmission lines, however in the meantime, a short-term solution would be to increase our power flexibility. Meaning that the energy consumption gets moved from hours of high demand to hours with low demand and by shutting off equipment. This is called power flexibility and has been researched more in recent times in projects like this. This project will mainly focus on demand-side flexibility which is about how the consumers use their electrical power. In collaboration with Uppsala Arenor och Fastigheter, power usage in one of the company’s properties will be made more flexible. This is achieved by mapping how much power each part of the property utilizes and estimating how much power the electrical equipment in that area consumes. Then determining if that piece of equipment can be either rescheduled to avoid hours of high-powerdemand in Uppsala or turned off without causing major consequences to the property. From this it will be decided if it can be added as a flexibility resource and after that the total power flexibility of the facility will be tallied. Lastly, suggestions on how to implement the power flexibility resources and recommendations for further improvements in future projects will be made. The results of the project were that the selected property Studenternas had an average power usage of 185kW during the day and of that 38% could be utilized as a power flexibility resource. The total power flexibility was therefore 71.2 kW which comes from the laundry rooms and the arena lighting while the other places in the facility contributed with a neglectable amount.
10

Inclusion of “value” concepts in evaluation of demand-side management in electric utility planning

Nelson, Sushil Kumar January 1992 (has links)
No description available.

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