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Energy efficiency: At whose expense? : A prospective study on the reception of the updated Energy Performance of Building Directives in SwedenBalika, Victoria January 2024 (has links)
This thesis investigates the reception of the updated directive, Energy Performance of Building Directive, from the EU. The focus of the study is to analyse eight referral responses from chosen stakeholders and investigate their perspectives on the updated directive, negative and positive, any specific interests, are there any patterns that emerge in their responses and what are their concerns regarding the possible impact on society. The intention is to map the possible outcomes in society, focusing on social sustainability, including issues such as economic impact, social justice, and community impact. The empirical material in this study is eight different referral responses on the updated version of the Energy Performance of Building Directive. The chosen methodical approach for this study is document analysis and thematic analysis. The findings are presented in four themes and later analysed and discussed through the lens of the chosen theoretical framework, which is environmental justice. The findings show a large focus on accessibility to housing, resources and cost efficiency, excessive regulation and micromanagement, and the need for financial support and incentives. The stakeholders fear that the number of details in the Energy Performance of Building Directive will sub-optimise Sweden’s production. Even though the directive states that this initiative will protect the most vulnerable groups in society, the stakeholders fear it will aggravate the situation due to increased rents and economic burdens in general for the whole society. This study concludes that such details should be discussed at the national level and it is important to include an environmental justice approach to avoid increasing the current inequalities and ensure that the needed transition will not be made at the expense of vulnerable segments of the population.
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Impact of ASHRAE standard 189.1-2009 on building energy efficiency and performanceBlush, Aaron January 1900 (has links)
Master of Science / Department of Architectural Engineering and Construction Science / Fred L. Hasler / The purpose of this report is to provide an introduction to the new ASHRAE Standard 189.1-2009, Standard for the Design of High-Performance Green Buildings. The report will include an overview of the standard to detail what the purpose, scope and requirements for high-performance buildings will be. The entire standard will be overviewed, but the focus of this paper is in the areas of energy efficiency and building performance. Next, the report will examine further impacts that the standard will have on the building design and construction industry. Chapter 3 includes the impact on other standards, specification writing and coordination of the design and construction teams. A case study of an office building is performed to compare a baseline building meeting ASHRAE Standard 90.1 to a building meeting the minimum standards of ASHRAE Standard 189.1. The case study compares the total annual energy use of the two projects to determine an expected energy savings. Based on this information, recommendations about the new standard will be discussed. Universities and government entities should require ASHRAE Standard 189.1 for new construction projects, to show willingness to provide sustainability in buildings. Finally, conclusions about how the standard will change and impact industry will be addressed. These conclusions will include issues with adopting ASHRAE Standard 189.1 as code as well as discussion on the LEED rating system.
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Low-energy buildings : energy use, indoor climate and market diffusionPersson, Johannes January 2014 (has links)
Low-energy buildings have, in recent years, gained attention and moved towards a large-scale introduction in the residential sector. During this process, national and international criteria for energy use in buildings have become stricter and the European Union has through the Energy Performance of Buildings Directive imposed on member states to adapt their building regulations for ‘Nearly Zero Energy Buildings’, which by 2021 should be standard for new buildings. With a primary focus on new terraced and detached houses, this thesis analyses how the concept of low-energy buildings may be further developed to reduce the energy use in the residential sector. The main attention is on the technical performance in terms of indoor climate and heat consumption as well as on the market diffusion of low-energy buildings into the housing market. A multidisciplinary approach is applied, which here means that the concept of low-energy buildings is investigated from different perspectives as well as on different system levels. The thesis thus encompasses methods from both engineering and social sciences and approaches the studied areas through literature surveys, interviews, assessments and simulations. The thesis reveals how an increased process integration of the building’s energy system can improve the thermal comfort in low-energy buildings. Moreover, it makes use of learning algorithms – in this case artificial neural networks – to study how the heat consumption can be predicted in a low-energy building in the Swedish climate. The thesis further focuses on the low-energy building as an element in our society and it provides a market diffusion analysis to gain understanding of the contextualisation process. In addition, it suggests possible approaches to increase the market share of low-energy buildings. / <p>QC 20140321</p>
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Energy efficiency through variable speed drive control on a cascading mine cooling system / Declan van GreunenVan Greunen, Declan January 2014 (has links)
An ever-expanding global industry focuses attention on energy supply and use. Cost-effective electrical energy production and reduced consumption pave the way for this expansion. Eskom’s demand-side management (DSM) initiative provides the opportunity for reduced electricity consumption with cost-effective implementation for their respective clients.
South African gold mines have to extend their operations to up to 4000 m below the surface to maintain profitable operations. Deep-level mining therefore requires large and energy-intensive cooling installations to provide safe working conditions. These installations generally consist of industrial chillers, cooling towers, bulk air coolers and water transport systems. All of these components operate in unison to provide chilled service water and cooled ventilation air underground.
In this study the improved energy efficiency and control of a South African gold mine’s cooling plant is investigated. The plant is separated into a primary and secondary cooling load, resulting in a cascading cooling system. Necessary research was conducted to determine the optimal solution to improve the plant’s performance and electrical energy usage.
Variable speed drives (VSD) were installed on the chiller evaporator and condenser water pumps to provide variable flow control of the water through the chillers, resulting in reduced motor electricity usage. Potential electricity savings were simulated. Proposed savings were estimated at 600 kW (13.6%) daily, with an expected saving of R 2 275 000 yearly, resulting in a payback period of less than 9 months. Results indicated are based on total savings, as VSD savings and control savings were combined.
The VSDs that were installed, were controlled according to an optimum simulation model’s philosophy. A real-time energy management program was used to control the VSDs and monitor the respective systems. The program’s remote capabilities allow for off-site monitoring and control adjustments. A control strategy, which was implemented using the management program, is discussed. Energy efficiency was achieved through the respective installations and control improvements.
The results were analysed over an assessment period of three months to determine the viability of the intervention. A newly installed Bulk Air Cooler (BAC) added to the service delivery of the cooling plant post installation of the VSDs. Focusing on service delivery to underground showed a savings of 1.7 MW (33.6%) daily and a payback period of 3.6 months (0.3 years). The overall implementation showed an average energy saving of 2.3 MW (47.1%) daily, with the result that a daily saving of R 23 988.20 was experienced, reducing the payback period to 2.3 months (0.2 years).
Through the installation of energy-efficiency technology and a suitable control philosophy, a cost-effective, energy-efficiency improvement was created on the case-study cooling plant. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
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A needs assessment of the market for resource efficiency and cleaner production services in the Vaal Triangle / Theunis Christoffel BothaBotha, Theunis Christoffel January 2014 (has links)
Major energy-consuming countries implemented new laws on energy-efficiency during the course of 2013. The new energy-efficiency law make provision for a 16% reduction in energy intensity by 2015 in China. New law in the United States of America requires new fuel-economy standards. European Union law aims for a cut of 20% in energy demand for the countries forming part of the European Union. Japan, with the country's new energy strategy aims to decrease electricity demand with 10% by 2030 as stipulated in the new energy strategy.
South Arica is currently experiencing a shortage in electricity generating capacity and operates within its reserve margin. The construction of new power stations is in process to address the shortage but Eskom must finance these assets by increasing the electricity tariff. Electricity prices are predicted to double from 2013 to 2017. In addition to the tariff increases, the Energy Conservation Scheme (ECS) is also planned by Eskom whereby all electricity consumers have to reduce their electricity consumption by 10% or face penalties.
Energy efficiency initiatives in South Africa will help meet some of the country's social, economic, and environmental goals. These initiatives are important as they immediately tackle the problem of electricity shortages and are a cost-effective way of increasing available electricity supply.
The aim of this study was to determine the need for businesses in the Vaal Triangle to be resource efficient and practice clean production in order to be able to capitalise on that need. With the current knowledge and technology available, Resource Efficiency and Cleaner Production (RECP) will prove to be a future necessity for industry. To determine the perceived readiness towards a green economy contribution is thus of importance.
The study did a review on RECP, energy efficiency, supply of energy in South Africa, focus areas for energy efficiency and the benefits thereof. The study discussed energy efficiency incentive schemes and subsidisation funds available in South Africa. The study assessed the primary fields for RECP, the drivers and barriers to RECP and the willingness to participate in RECP initiatives in the Vaal Triangle. The study concluded that there exists a need in the Vaal Triangle for RECP initiatives and that there exists potential for the start of a green economy in the region. The research indicated the reaction towards RECP initiatives to be very positive in the studied region. / MBA, North-West University, Potchefstroom Campus, 2015
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Energy efficiency through variable speed drive control on a cascading mine cooling system / Declan van GreunenVan Greunen, Declan January 2014 (has links)
An ever-expanding global industry focuses attention on energy supply and use. Cost-effective electrical energy production and reduced consumption pave the way for this expansion. Eskom’s demand-side management (DSM) initiative provides the opportunity for reduced electricity consumption with cost-effective implementation for their respective clients.
South African gold mines have to extend their operations to up to 4000 m below the surface to maintain profitable operations. Deep-level mining therefore requires large and energy-intensive cooling installations to provide safe working conditions. These installations generally consist of industrial chillers, cooling towers, bulk air coolers and water transport systems. All of these components operate in unison to provide chilled service water and cooled ventilation air underground.
In this study the improved energy efficiency and control of a South African gold mine’s cooling plant is investigated. The plant is separated into a primary and secondary cooling load, resulting in a cascading cooling system. Necessary research was conducted to determine the optimal solution to improve the plant’s performance and electrical energy usage.
Variable speed drives (VSD) were installed on the chiller evaporator and condenser water pumps to provide variable flow control of the water through the chillers, resulting in reduced motor electricity usage. Potential electricity savings were simulated. Proposed savings were estimated at 600 kW (13.6%) daily, with an expected saving of R 2 275 000 yearly, resulting in a payback period of less than 9 months. Results indicated are based on total savings, as VSD savings and control savings were combined.
The VSDs that were installed, were controlled according to an optimum simulation model’s philosophy. A real-time energy management program was used to control the VSDs and monitor the respective systems. The program’s remote capabilities allow for off-site monitoring and control adjustments. A control strategy, which was implemented using the management program, is discussed. Energy efficiency was achieved through the respective installations and control improvements.
The results were analysed over an assessment period of three months to determine the viability of the intervention. A newly installed Bulk Air Cooler (BAC) added to the service delivery of the cooling plant post installation of the VSDs. Focusing on service delivery to underground showed a savings of 1.7 MW (33.6%) daily and a payback period of 3.6 months (0.3 years). The overall implementation showed an average energy saving of 2.3 MW (47.1%) daily, with the result that a daily saving of R 23 988.20 was experienced, reducing the payback period to 2.3 months (0.2 years).
Through the installation of energy-efficiency technology and a suitable control philosophy, a cost-effective, energy-efficiency improvement was created on the case-study cooling plant. / MIng (Mechanical Engineering), North-West University, Potchefstroom Campus, 2014
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A needs assessment of the market for resource efficiency and cleaner production services in the Vaal Triangle / Theunis Christoffel BothaBotha, Theunis Christoffel January 2014 (has links)
Major energy-consuming countries implemented new laws on energy-efficiency during the course of 2013. The new energy-efficiency law make provision for a 16% reduction in energy intensity by 2015 in China. New law in the United States of America requires new fuel-economy standards. European Union law aims for a cut of 20% in energy demand for the countries forming part of the European Union. Japan, with the country's new energy strategy aims to decrease electricity demand with 10% by 2030 as stipulated in the new energy strategy.
South Arica is currently experiencing a shortage in electricity generating capacity and operates within its reserve margin. The construction of new power stations is in process to address the shortage but Eskom must finance these assets by increasing the electricity tariff. Electricity prices are predicted to double from 2013 to 2017. In addition to the tariff increases, the Energy Conservation Scheme (ECS) is also planned by Eskom whereby all electricity consumers have to reduce their electricity consumption by 10% or face penalties.
Energy efficiency initiatives in South Africa will help meet some of the country's social, economic, and environmental goals. These initiatives are important as they immediately tackle the problem of electricity shortages and are a cost-effective way of increasing available electricity supply.
The aim of this study was to determine the need for businesses in the Vaal Triangle to be resource efficient and practice clean production in order to be able to capitalise on that need. With the current knowledge and technology available, Resource Efficiency and Cleaner Production (RECP) will prove to be a future necessity for industry. To determine the perceived readiness towards a green economy contribution is thus of importance.
The study did a review on RECP, energy efficiency, supply of energy in South Africa, focus areas for energy efficiency and the benefits thereof. The study discussed energy efficiency incentive schemes and subsidisation funds available in South Africa. The study assessed the primary fields for RECP, the drivers and barriers to RECP and the willingness to participate in RECP initiatives in the Vaal Triangle. The study concluded that there exists a need in the Vaal Triangle for RECP initiatives and that there exists potential for the start of a green economy in the region. The research indicated the reaction towards RECP initiatives to be very positive in the studied region. / MBA, North-West University, Potchefstroom Campus, 2015
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Thermal performance of heavy-weight and light-weight steel frame construction approaches in the central Pretoria climateKumirai, T., Conradie, D.C.U. January 2013 (has links)
Published Article / The purpose of this paper is to analyse the thermal performance of two buildings. The one has a large thermal mass and the other a highly insulated low thermal mass. A typical 120 m2 suburban building was modelled in Ecotect. As part of the model infiltration rate, wind sensitivity and a central Pretoria weather file were used. New material composites were introduced in the materials database to represent typical building materials used in the construction of heavy and light-weight buildings in South Africa. The thermal characteristics of these new materials were then calculated within Ecotect. Ecomat was used to calculate thermal lag which was used as an additional input into Ecotect. The research indicates that a low thermal mass and highly insulated building have been shown to use 18.3% less annual space heating and cooling energy when compared to the high thermal mass building. The good thermal performance results of the light-weight building will help in clearing scepticism to adopting this construction technology in southern Africa where high thermal mass masonry is still predominant.
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Radio and Sensor Interfaces for Energy-autonomous Wireless SensingMao, Jia January 2016 (has links)
Along with rapid development of sensing and communication technology, Internet of Things (IoTs) has enabled a tremendous number of applications in health care, agriculture, and industry. As the fundamental element, the wireless sensing node, such as radio tags need to be operating under micro power level for energy autonomy. The evolution of electronics towards highly energy-efficient systems requires joint efforts in developing innovative architectures and circuit techniques. In this dissertation, we explore ultra-low power circuits and systems for micropower wireless sensing in the context of IoTs, with a special focus on radio interfaces and sensor interfaces. The system architecture of UHF/UWB asymmetric radio is introduced firstly. The active UWB radio is employed for the tag-to-reader communication while the conventional UHF radio is used to power up and inventory the tag. On the tag side, an ultra-low power, high pulse swing, and power scalable UWB transmitter is studied. On the reader side, an asymmetric UHF/UWB reader is designed. Secondly, to eliminate power-hungry frequency synthesis circuitry, an energy-efficient UWB transmitter with wireless clock harvesting is presented. The transmitter is powered by an UHF signal wirelessly and respond UWB pulses by locking-gating-amplifying the sub-harmonic of the UHF signal. 21% locking range can be achieved to prevent PVT variations with -15 dBm injected power. Finally, radio-sensing interface co-design is explored. Taking the advantage of RC readout circuit and UWB pulse generator, the sensing information is directly extracted and transmitted in the time domain, exploiting high time-domain resolution UWB pulses. It eliminates the need of ADC of the sensor interface, meanwhile, reduces the number of bits to be transmitted for energy saving. The measurement results show that the proposed system exhibits 7.7 bits ENOB with an average relative error of 0.42%. / <p>QC 20160412</p>
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Environmental Natural Processes that Achieve Thermal Comfort in Multifamily Buildings in Hot Arid RegionsMoreno, Paola January 2015 (has links)
Buildings, especially in hot climates, consume a lot of energy when people want to be comfortable inside them, which translates to very expensive fees each month. The most innovative response to this problem is renewable energy, that is used, in this case, to run mechanical HVAC systems. Renewable energy is the solution for many problems, but to avoid urban heat islands when using excessive HVAC systems (powered by renewables), and to solve thermal comfort-related problems, there has to be other solution. The major challenge to find it would be to have a change of thinking process. If a building in a hot-arid region uses natural processes to emulate the functions of HVAC systems, and the proper passive strategies, then, it will provide thermal comfort to its users, diminishing the need of a mechanical system. This hypothesis will be carried out by extracting the natural processes found in a specific case in nature, applying them into a building's design, and then simulating its energy efficiency with the adequate software. There will be a comparison of the same proposed building without the natural processes, to have tangible numbers showing that these proposed strategies, in fact, work. With explanatory detailed diagrams and the energy analysis, the hypothesis could be proven correct or incorrect. The significance of this approach relies on the proximity to the natural processes that have been working in different aspects of life since the beginning of time. They have been there all the time, waiting until architects, engineers, and people in general use them, instead of making more new energy-using inventions. By having the numbers from a conventional building and the ones of the proposed building, and the right environmental diagrams, the experiment should be valid. In the near future, there should be more research focused on nature and its processes, in order to be able to reduce the use of mechanical systems, and with that, reduce the energy use and the carbon footprint.
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