A dissertation submitted to the Faculty of Engineering and the Built Environment at the University of the Witwatersrand, in fulfilment of the requirements of a Master of Science in Building. / Introduction: Literature shows that an organization that participates in learning broadens its competitive advantage, capabilities and efficiency ensuring overall improved performance. This study reviews organizational learning in small and medium Energy Service Companies (ESCos) undertaking energy efficiency projects in the South African building industry. In addition, the study examines what impact the organizational learning has on the performance of ESCos. Furthermore factors and practices that influence organizational learning in small and medium sized ESCos are identified and reviewed. Aim: The study develops a framework for the effective learning practices which lead to better performance in implementing energy effiency projects. Design/methodology/approach: The study uses a combination of interviews, document and literature review. Interviews and literature were used to gather information on organizational learning and learning practices in small and medium ESCos undertaking energy efficiency building projects. Company documents, government policies and Eskom’s operational documents were documents used for analysis. All the findings were triangulated to ensure validity and reliability. Outcome: ESCOs are instrumental in promoting energy efficiency. This study identified current learning practices and the factors that promote learning within ESCos. This enables ESCos to strategize on the possible improvement on their performances. Keywords: Buildings, Energy Efficiency, Energy Service Companies (ESCos), Organizational Learning, Performance, Small and Medium Enterprises (SMEs), and South Africa 1 Eskom is a utility company in South Africa that generates, transmits and distributes electricity to various sectors within the country and other SADC region.

Submitted by Silvana Teresinha Dornelles Studzinski (sstudzinski) on 2016-12-20T16:07:36Z No. of bitstreams: 1 Juliana Damasio Waschevicz_.pdf: 2480134 bytes, checksum: 947a7c004c2322311b94d6b838c14139 (MD5) / Made available in DSpace on 2016-12-20T16:07:36Z (GMT). No. of bitstreams: 1 Juliana Damasio Waschevicz_.pdf: 2480134 bytes, checksum: 947a7c004c2322311b94d6b838c14139 (MD5) Previous issue date: 2016-05-11 / FAPERGS - Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul / Esta dissertação apresenta uma análise da relação entre o consumo energético para climatização de uma edificação comercial com os sistemas de ar condicionado do tipo SPLIT e VRF e, alguns parâmetros arquitetônicos da envoltória que foram variados no modelo de referência. As análises foram realizadas por simulação computacional, através do programa EnergyPlus. Foram simulados casos com variações no modelo de referência, de tipos de cobertura e de fechamento opaco do envelope, característica dos vidros, inserção de brises verticais e horizontais e redução do percentual de área de janelas nas fachadas, para os dois sistemas de ar condicionado. Adotou-se o clima de Porto Alegre, o qual está localizado na Zona Bioclimática Brasileira 3. O modelo de referência adotado foi criado a partir de um levantamento fotográfico de edificações comerciais com mais de quatro pavimentos na cidade de Porto Alegre. A partir deste levantamento, a tipologia que foi adotada representa um edifício de dez pavimentos com perímetro de dimensões 27 x 7,5 m e pé-direito de 2,60 m. Para analisar o comportamento energético do modelo de referência foram inseridos dados dos componentes construtivos, do padrão de ocupação, das cargas energéticas do sistema de iluminação e dos equipamentos, do condicionamento de ar e de infiltração. Com esses dados inseridos no EnergyPlus, foi possível dimensionar a carga térmica dos equipamentos de ar condicionado e então iniciar as simulações onde os materiais foram variados, um por vez. Na análise de todas as variações propostas, observou-se que a alteração das características do vidro incolor 3mm pelas do vidro refletivo 6 mm, foi o parâmetro que mais influenciou na redução do consumo energético para refrigeração. O agrupamento das três melhores soluções: vidro refletivo de 6 mm, brises horizontais e cobertura metálica com isolamento, gerou uma redução no consumo do sistema de condicionamento de ar de 35,7% com o SPLIT, passando de 53,4 kWh/m2 para 34,33 kWh/m2, e 41,94% para o VRF, reduzindo de 36,04 kWh/m2 para 20,92 kWh/m2. Também pode-se observar que o COP real dos equipamentos de condicionamento de ar foi bem maior que o nominal na maior parte do tempo, com uma média de aproximadamente 4,5 para o SPLIT e 6,2 para o VRF. / This thesis presents an analysis of the relationship between energy consumption for cooling of a commercial building with air conditioning systems type SPLIT and VRF and some varied architectural parameters in the reference model. The analyzes were carried out by computer simulation, using EnergyPlus. Several changes were simulated with variations in the reference model, like roof types, envelope thermal insulation, window glass types, vertical and horizontal louvers and smaller window to wall ratio on the facades, for both air conditioning systems. The climate of Porto Alegre was adopted, which is located in the Brazilian Bioclimatic Zone 3. The reference model was created from a photographic survey of commercial buildings over four stories in the city of Porto Alegre. From this survey, a building with ten floors measuring 27 x 7.5 m and ceiling height of 2.60 m was designed. To analyze the energy behavior of the reference model, building components were inserted, like occupation schedule, lighting system and equipment loads, air conditioning and infiltration. With these data entered in EnergyPlus thermal load was determined and air conditioning equipment selected and inserted according with performance data obtained from equipment suppliers. The simulations of the mentioned changes were made one at a time. Comparing all proposed variations, the change of the 3 mm clear glass by the reflective 6 mm glass, was the most influencing parameter in reducing energy consumption for cooling. When grouping the top three solutions: reflective 6 mm glass, horizontal blinds and metalic roof with insulation, an overall reduction in consumption in air conditioning system of 35.7% with SPLIT, from 53.4 kWh/m2 to 34.33 kWh/m2, and 41.94% for the VRF, reducing from 36.04 kWh/m2 to 20.92 kWh/m2 was obtained. It may also be noted that the actual COP of the air conditioning equipment was much higher than the nominal most part of the time, with an average of approximately 4.5 for the SPLIT system and 6.2 for the VRF system.

Thesis. 1975. Ph.D.--Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. / Vita. / Bibliography: leaves 121-125. / Ph.D.

One of the greatest challenges that will face humanity in the 21st century is the issue of climate change brought about by emissions of greenhouse gases. Energy use is one of the primary sources of greenhouse gas emissions. However, it is also one of the most important contributors to improved human welfare over the past two centuries and will continue to be so for years to come. This quandary has led a number of researchers to suggest that geoengineering may be required in order to allow for continued use of fossil fuels while at the same time mitigating the effects of the associated greenhouse gas emissions on the global climate. The goal of this research was to develop a model that would allow decision-makers and policy analysts to assess the optimal mix of energy and geoengineering resources needed to meet global or regional energy demand at the lowest cost while accounting for appropriate emissions, greenhouse gas concentration, or temperature rise constraints. The resulting software model is called the Combined Energy and Geoengineering Optimization Model (CEAGOM). CEAGOM was then used to analyze the recently announced U.S.-China emissions agreement and to assess what the optimal global energy resource mix might be over the course of the 21st century, including the associated potential need for geoengineering. These analyses yielded optimal mixes of energy and geoengineering resources that could be used to inform regional and global energy and climate management strategies.

This study is aimed at developing policies for energy efficiency by observing the past changes of energy use in Indonesia???s manufacturing sector over the period 1980???2000, and to investigate mitigation options for energy-related CO2 emissions in the sector. The first part of the study uses decomposition analysis to assess the effect of the changes in energy consumption and the level of CO2 emissions, while the second part investigates energy efficiency improvement strategies and the use of economic instruments to mitigate CO2 emissions in the manufacturing sector. Economic activity was the dominant factor in increasing energy consumption over the whole period of analysis, followed by the energy intensity effect and then the structural effect. The increase in aggregate energy intensity over the period 1980-2000 was mainly driven by the energy intensity effect. In turn, the technical effect was the dominant contributor to changes in energy intensity effect, with the fuel-mix effect being of lesser importance. Changes in CO2 emissions were dominated by economic activity and structural change. Sub-sectors that would benefit from fuel switching and energy efficiency improvements are the textile, paper, and non-metal sub-sectors. Three main options for reducing CO2 emissions from the manufacturing sector were considered: the imposition of a carbon tax, energy efficiency initiatives, and other mitigation measures. A carbon tax was found to reduce sectoral emissions from the direct use of oil, gas and coal, but increased the demand for electricity. At the practical level, energy efficiency improvements can be implemented by adopting energy efficient technologies that can reduce aggregate energy intensity up to 37.1 per cent from the base-year level, estimated after imposition of a carbon tax at $30 per tonne of carbon. A major priority for energy efficiency improvements was found to be in the textile and the paper and chemical sub-sectors. A mitigation measure such as the Clean Development Mechanisms could be encouraged in order to reduce projected emission levels. The preferred option would be the adoption of energy efficient technologies in the textile, chemical, paper and non-metal sub-sectors.

<p>Three of the most important factors with regards to wireless multi-hop networks, namely reachability, energy consumption and network stability are considered in our transmitter macrodiversity supported broadcasting routing algorithms. Broadcasting applications are not only used to send routing table, queries, programming logic, any specific request etc. to all the nodes from access point but are also capable of playing a vital role in wireless TV distributions and visual sensor networks. All the algorithms are simulated in the MATLAB environment in which the nodes are random and are battery driven on a multi-hop randomized topology. Four new single frequency network (SFN) based algorithms (SFN-A, SFN-B, SFN-C and SFN-D) are formed in order to work over multi-hopping and where three of the algorithms SFN-A, SFN-B and SFN-D bear more or less the same amount of reachability. These three algorithms are able to reach more than 90% of reachability in only Tx power -8dBm whereas non-SFN requires -4dBm and SFN-C requires -2dBm and, in addition can achieve a maximum of 29 percentage points more reachability than the non-SFN algorithm. However, the best algorithm SFN-D consumes a maximum of 58.76% less energy than the SFN-A and a maximum of 14.28% less energy than the SFN-B. The SFN-D algorithm achieves a maximum 3.43 dB diversity gain together with the maximum 37.33% energy consumption gain in comparison to the non-SFN algorithm.</p>

According to the Environmental Kuznets Curve (EKC), economic growth will eventually cause carbon dioxide emissions to decrease. Is this the case in Sweden? A time series covering the period 1800-1995 is used to analyze the relation between carbon dioxide emissions and income per capita in Sweden. The empirical results indicate that an EKC for carbon dioxide is highly likely to exist in Sweden for the examined period. To take the analysis further, a cross-section data set is employed to examine the relationship between carbon dioxide emissions, income per capita and 4 other potentially influential variables in 75 countries. Only carbon intensity of energy is significant for carbon dioxide emissions. This implies that the utilized energy source is of importance, and it is crucial to separate energy consumption from carbon dioxide emissions. Emissions is a matter of structural aspects such as the type of industry and production a country comprise, and what type of energy that is consumed; not merely the quantity of energy. Sweden has experienced a shift in production techniques and in energy supply, and the energy-efficiency has improved during the past 100 years. It is consequently plausible to believe that it is not a critical income per capita which decreases CO 2  emissions – it is the “right” energy sources, energy efficiency and improved technology.

This rapport contains an examination of the energy consumption of a kindergarten, which areas that have the largest impact on the energy consumption and what can be done to reduce those areas in ways that are relatively easy and profitable. It is also analyzed if it is possible to reduce the energy consumption from today’s consumption to a consumption that fulfils the demands placed on low energy houses by FEBY. The focus has been on reducing the energy consumption of the areas ventilation, heating system and hot water system, since those seemed to be the easiest ones to affect and since the building is quite recently built. There are different kinds of ventilation systems, at the moment the building have a CAV-system, which means that the ventilation is too high during large parts of the day. There are different ways to manage the ventilation system, for example presence detection, humidity sensors, CO2 sensors, temperature sensors and season adjustment. Many of those are in the end dependent on CO2 sensors to guarantee a good indoor climate, therefore the focus have been placed on this system.   The building is heated through district heating which is relatively easy to connect to a couple of sun panels to contribute to the heating system and hot water system. There are different ways of connecting district heating with solar panels and those are described, as well as the cost and the repayment time. A comparison with a building with an electric heating system has been made as well. It is important to get solutions that are profitable, that the repayment time isn’t too long. Solar cells and wind turbines are examined as well, but the repayment time for solar cells are too long at the moment. The repayment time for solar cells varies between 42 - 75 years, while the expected lifetime is 25 years. Concerning ventilation, a reduced ventilation of 10, 20, 30, 40 and 50 % have been examined. With only reduced ventilation the demands on low energy houses could not be matched, but it was possible in two cases with the use of solar panels. The usage of a wind turbine meant that the ventilation had to be reduced even less to match the demands on low energy houses. The repayment times for the solar panels and the wind turbine are both around 14 years. / Rapporten behandlar en undersökning av energiförbrukningen vid en projekterad förskola och vilka poster som har störst inverkan på energiförbrukningen, samt vad som kan göras för att åtgärda dessa på ett sätt som är relativt enkelt och som är lönsamt. Det ses över om det är möjligt att få ner energiförbrukningen från dagens förbrukning som uppfyller BBR:s krav, till att uppfylla de lägre energikraven som gäller för minienergihus enligt FEBY. Med utgångspunkt i energiförbrukningsberäkningen som gjorts och det faktum att förskolan är relativt nybyggd så har fokus lagts på att minska ner posterna ventilation, värmesystemet och varmvattnet då dessa är de poster som är lättast att påverka. När det gäller ventilation finns olika styrsätt, byggnaden har i nuläget ett CAV-system, vilket innebär att ventilation under stora delen av dagen är för hög. Det finns olika saker att styra ventilationen och minska ner den på, däribland närvarogivare, fuktgivare, koldioxidgivare, temperaturgivare samt årstidsanpassning. Många av dessa är dock i slutändan beroende av koldioxidgivare för att garantera inomhusklimatet, så därför har fokus lagts på detta system. Byggnaden värms upp via fjärrvärme och det är relativt enkelt att koppla på solfångare för hjälp av uppvärmning av värmesystemet och varmvattnet. Det finns olika sätt att koppla in solfångare på system med fjärrvärme och de olika sätten beskrivs och undersöks, liksom kostnad och återbetalningstid för en anläggning med solfångare. En jämförelse med en byggnad med eluppvärmning har också gjorts. Det är viktigt att få ekonomisk lönsamhet i det hela och således att återbetalningstiden inte ska vara för lång. Även solceller och vindkraftverk tas upp, dock är återbetalningstiden för solceller i nuläget alltför lång för att vara ekonomiskt försvarbart. Återbetalningstiden för solceller varierar mellan 42 – 75 år, medan den beräknade livslängden ligger på 25 år. När det gäller ventilationen så har minskad ventilation med 10, 20, 30, 40 och 50 % undersökts. Med enbart minskad ventilation kan inte kravet för lågenergihus uppfyllas, men inräknat solfångare så nåddes i två fall lågenergihus. Till sist så innebar medräknandet av ett vindkraftverk att ventilationen inte behövdes minskas lika mycket för att uppfylla kraven för lågenergihus. Återbetalningstiden för solfångarna beräknades till 14 år och återbetalningstiden för vindkraftverket till 14 år.

The objective of the proposed research is to develop an analytical model that predicts performance and power for many-core architecture and further propose a mechanism, which leverages the analytical model, to enable energy-efficient execution of an application. The key insight of the model is to investigate and quantify a complex relationship that exists between the thread-level parallelism and memory-level parallelism for an application on a given many-core architecture. Two metrics are proposed: memory warp parallelism (MWP), which refers to the number of overlapping memory accesses per core, and computation warp parallelism (CWP), which characterizes an application type. By using these metrics in addition to the architectural and application parameters, the overall application performance is produced. The model uses statically-available parameters such as instruction-mixture information and input-data size, and the prediction accuracy is 13.3% for the GPU-computing benchmarks. Another important aspect of using many-core architecture is reducing peak power and achieving energy savings. By using the proposed integrated power and performance (IPP) framework, the results showed that different optimization points exist for GPU architecture depending on the application type. The work shows that by activating fewer cores, 10.99% of run-time energy consumption can be saved for the bandwidth-limited benchmarks, and a projection of 25.8% energy savings is predicted when power-gating at core level is employed. Finally, the model is shifted to throughput using OpenCL for targeting more variety of processors. First, multiple outputs relating to performance are predicted, including upper-bound and lower-bound values. Second, by using the model parameters, an application can be categorized into a different category, each with its own suggestions for improving performance and energy efficiency. Third, the bandwidth saturation point accuracy is significantly improved by considering independent memory accesses and updating the performance model. Furthermore, a trade-off analysis using architectural and application parameters is straightforward, which provides more insights to improve energy efficiency. In the future, a computer system will contain hundreds of heterogeneous cores. Hence, it is mandatory that a workload gets scheduled to an efficient core or distributed on both types of cores. A preliminary work by using the analytical model to do scheduling between CPU and GPU is demonstrated in the appendix. Since profiling phase is not required, the kernel code can be transformed to run more efficiently on the specific architecture. Another extension of the work regarding the relationship between the speed-up and energy efficiency is mathematically derived. Finally, future research ideas are presented regarding the usage of the model for programmer, compiler, and runtime for future heterogeneous systems.

Although evolving mobile technologies bring millions of users closer to the vision of information anywhere-anytime, device battery depletions hamper the quality of experience to a great extent. We argue that the design of energy-efficient solutions starts by energy-awareness and propose EnergyBox, a tool that provides accurate and repeatable energy consumption studies for 3G and WiFi transmissions at the user end. We recognize that the energy consumption of data transmission is highly dependable on the traffic pattern, and provide the means for trace-based iterative packet-driven simulation to derive the operation states of wireless interfaces. The strength of EnergyBox is that it allows to modularly set the 3G network parameters specified at operator level, the adaptive power save mode mechanism for a WiFi device, and the different power levels of the operation states for different handheld devices. EnergyBox enables efficient energy consumption studies using real data, which complements the device-dependent laborious physical power measurements. Using real application transmission traces, we have validated EnergyBox showing an accuracy range of 94-99% for 3G and 93-99% for WiFi compared to the real measured energy consumption by a 3G modem and a smartphone with WiFi.