• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 52
  • 21
  • 12
  • 3
  • 2
  • 1
  • 1
  • Tagged with
  • 105
  • 105
  • 68
  • 33
  • 31
  • 30
  • 26
  • 25
  • 23
  • 22
  • 19
  • 18
  • 17
  • 16
  • 16
  • 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.
71

SELF-SUFFICIENT OFF-GRID ENERGY SYSTEM FOR A ROWHOUSE USING PHOTOVOLTAIC PANELS COMBINED WITH HYDROGEN SYSTEM : Master thesis in energy system

Maxamhud, Mahamed, Shanshal, Arkam January 2020 (has links)
It is known that Sweden is categorised by being one of the regions that experience low solar radiation because it is located in the northern hemisphere that has a low potential of solar radiation during the colder seasons. The government of Sweden aim to promote a more sustainable future by applying more renewable initiative in the energy sector. One of the initiatives is by applying more renewable energy where PV panels will play a greater role in our society and in the energy sector. However, the produced energy from the PV panels is unpredictable due to changes in radiation throughout the day. One great way to tackle this issue is by combining PV panels with different energy storage system. This thesis evaluates an off-grid rowhouse in Eskilstuna Sweden where the PV panels are combined with a heat pump, thermal storage tank, including batteries and hydrogen system. The yearly electrical demand is met by utilizing PV panels, battery system for short term usage and hydrogen system for long-term usage during the colder seasons. The yearly thermal demand is met by the thermal storage tank. The thermal storage tank is charged by heat losses from the hydrogen system and thermal energy from heat pump.The calculations were simulated in Excel and MATLAB where OPTI-CE is composed with different components in the energy system. Furthermore, the off-grid household was evaluated from an economic outlook with respect to today’s market including the potential price decrease in 2030.The results indicated that the selected household is technically practicable to produce enough energy. The PV panels produces 13 560 kWh annually where the total electrical demand reaches 6 125 kWh yearly (including required electricity for the heat pump). The annual energy demand in terms of electricity and thermal heat reaches 12 500 kWh which is covered by the simulated energy system. The overproduction is stored in the batteries and hydrogen storage for later use. The back-up diesel generator does not need to operate, indicating that energy system supplies enough energy for the off-grid household. The thermal storage tank stores enough thermal energy regarding to the thermal load and stores most of the heat during the summer when there are high heat losses due to the charge of the hydrogen system. The simulated energy system has a life cycle cost reaching approximately k$318 with a total lifetime of 25 years. A similar off-grid system has the potential to reduce the life cycle cost to k$195 if the energy system is built in 2030 with a similar lifespan. The reduction occurs due to the potential price reduction for different components utilized in the energy system.
72

Využití fotovoltaických systémů v Off-grid aplikacích / Use of Photovoltaic Systems in Off-grid Applications

Straka, Michal January 2012 (has links)
This masters thesis deals with the use of off-grid photovoltaic systems. First we explain the problems associated with the power and energy potential of photovoltaic system components, design of photovoltaic systems for autonomous operation and the financial evaluation. The result of the masters thesis is to create an application used to design the island system in the whole output range (the smallest power systems to house systems application). The conclusion of the masters thesis is devoted to designing three type of projects from our application – a garden cottage, a family cottage and the house.
73

Ekonomicko-energetická analýza rodinného domu závislého na solární energii / Economic and Energy Analysis of House Dependent on Solar Energy

Losert, Pavel January 2015 (has links)
Searching for savings and lowering costs of economical housing is still very actual topic nowadays. These actions are more affordable with growing energy costs. New development in technology and mass production make using of solar installations more effective and cheaper. By harvesting solar energy we don't have to pollute an environment and we can also stop production of greenhouse gases which cause changing of planetary climate.
74

Kogenerační zdroj / Cogeneration Unit

Jančok, Lukáš January 2013 (has links)
V diplomové práci je krok po kroce vypracováno řešení zabezpečení energetického zdroje pro typické město v Sibiřské oblasti. Data, která tvoří zadání, byla získána od zákazníka pomocí dotazníku, protože pro nás oblast v čase vypracování nebyla dostupná. Na základě informací o aktuální energetické situaci, obyvatelstvu a dřevospracujícímu průmyslu je vybrána vhodná technologie pro zabezpečení tepla a elektrické energie. Druh zdroje byl vybrán dle dostupného paliva a následně byl proveden výpočet a design en- ergetického zdoje založeného na Rankine Clausiovém cyklu. Řešení obsahuje technický i ekonomický návrh. Technické řešení ukázalo, že nejdůležitější parametry jsou spolehlivost, bezpečnost a jednoduchost řešení. Design sítí, přídavných zařízení a plánování údržby není obsahem této práce. O dalších projektových krocích pojednává závěr.
75

Are solar home systems a more financially viable method of electrifying Ghana households?

Radebe, Thandwefika 24 February 2021 (has links)
Africa still has the lowest electrification rates in the world with over 600 million people estimated to be living without access to electricity. What makes the challenge even greater for Africa is that the continent is so sparsely populated that building grid infrastructure is not viable in many cases. However, “pay-as-you-go” solar home systems have provided the continent with the opportunity to correct its electrification deficit. These innovations are not new and many of the costs of operating these systems have reached grid parity when one considers the Levelized Cost of Energy Model. However, these projects still fail to meet institutional investors' bankability criteria. The aim of this study is to try and understand whether solar home systems provide the investor with an opportunity to make a larger risk-adjusted return versus existing grid-based power station projects being considered on the continent. This study uses Ghana's recently built Kpone power station as a case study to complete this analysis. The study also seeks to assess what viability criteria is employed by a broad base of investors if they were to consider funding off-grid power. The study makes use of the Net Present Value model to compare the returns for Kpone and Zola Electric's Infinity solar home system. The study also conducts inductive qualitative analysis to try and ascertain what criteria is assessed for project viability and then builds a conceptual framework for assessing future projects. The study found that Kpone provided a better risk-adjusted return to that of Zola Electric's solar home system, largely because of Kpone's project finance structure reducing the risk of the investment. Our findings also show that investment ticket size, company track record and management track record are among the most highly considered criteria for investments into off-grid companies.
76

Integrated Energy Recovery Scenarios of Biomass Residues in the Non-interconnected Island of Crete : A Pre-Feasibility Study in Greece

Papalexandrou, Tryfon January 2015 (has links)
The cornerstone of our production system is based on the concept “take, make, waste”. Moreover, the manufacture of a product requires the input of energy and raw materials which produce waste and products. The latter ultimately end up becoming wastes. In other words, the root problem of this production system is that is designed on a linear, one-way cradle-to grave model (McDonough, W. and Braungart, M., 2002). This approach coupled with the population explosion and our thirst for growth has led to an unprecedented pressure to the environment. The consequences are multiple; climate change, dwindling energy resources and waste generation. This study lies in two pillars: the concept of sustainable development and the waste management hierarchy. The idea was how these two fundamental concerns (energy generation and waste production) could be tackled. This study assesses the availability of biomass residues and wastes in the off-grid island of Crete with the aim to ‘close the loop’ by converting waste to an energy resource. In addition, the exploration of the most sustainable energy generation solutions was attempted in order to drive forward the synergies between biomass waste production and energy generation. The collected information was extracted from the literature about agricultural, livestock, Municipal Solid Waste (MSW) and Industrial & Commercial (I&C) waste. It is also based on numerous interviews to waste management associations, the Greek Ministry of Rural Development & Food and all the Waste Water Treatment Plants in the island were analysed in order to shed light on the potential energy generation from all the aforementioned biomass sources and its contribution to the electric energy production system of Crete. It is considered that the biomass potential in Crete is a sleeping giant. There is considerable potential for biomass-to-energy technologies in Crete providing improved rural energy services based on agricultural residues. From the findings of this study it appears that the biomass potential is more than estimated in previous papers. Based on the findings it is concluded that the largest portion of Crete’s biomass potential is agricultural residues and animal wastes. The utilisation of low-cost biomass power in Crete could help provide cleaner, more efficient energy services and to reduce the island’s economic and environmental vulnerability. Biomass can provide both base load power and turn into liquid transportation fuels and contributes to reducing energy dependence due to import fuel from the mainland. In terms of the study’s goal to select the most sustainably viable biomass-to-energy technologies, that was based on the multi-criteria methodology. A number of integrated biomass-to-energy alternatives were assessed against technical, environmental, financial and social criteria with the aim to assist the regional authority’s decision making process of energy generation planning. From the final screening of the integrated biomass-to-energy alternatives it was concluded that the best in a descending order technologies from the regional authority’s standpoint are: F - Anaerobic digestion & Fuel cell; E – Anaerobic digestion & Gas engine; C - Gasification & Gas engine; A – Combustion & Steam turbine; and B – Gasification & Steam turbine.
77

Sustainability Comparison between EnDev and not-EnDev Micro-Hydro Power (MHP) in Indonesia : Analysis of the long-term technical, social, environmental and economic sustainability of the rural energy infrastructure of MHP in Indonesia

Ranzanici, Andrea January 2013 (has links)
The Energising Development (EnDev) initiative, for which the GIZ acts as implementing agency, promotes the supply of modern energy technologies to households and small‐scale businesses in the rural communities of 24 countries in Africa, Latin America and Asia. In Indonesia, this has been achieved through off‐grid micro‐hydro (MHP) and solar power mini‐grids and since 2006 230 MHP and 117 solar projects have been supported to varying degree at substantial cost, reaching more than 167 thousand people. The objective of this study is to assess this contribution of the EnDev-Indonesia initiative regarding the MHP performance and ultimate long‐term sustainability prospect of the rural energy infrastructure in the country. As such a comparison between EnDev and non-EnDev MHP projects in the country was undertaken and based on the established Key Performance Indicators (KPIs) survey methodology and the DB&TO sustainability model specifically fashioned for the purpose of this study. This approach involved on‐site visits and comprises technical, social, economic and environmental aspects. As a result, the analysis has shown important differences among the different supporting schemes, with the second implementing phase (2009‐2012) of EnDev outranking the other systems largely due to the high level of technical sustainability achieved by these sites. Such a good performance is even more surprising considering that the EnDev1 sites implemented during the first phase of the program in the early years were among the least‐sustainable investigated in this study. However, despite the high costs necessary to reach such a high level of sustainability as regards the quality of the civil works and electro‐mechanical equipments, this aspect alone was found not enough to guarantee the long‐term sustainability of MHP in Indonesia. On the other hand, lack of social and economic sustainability appeared having fatal consequences onthe operations of many plants. Therefore, such complex interrelation among the different aspects of sustainability was investigated and also external factors, like the regional and cultural differences among the different beneficiaries, were addressed. Finally, recommendations for future eventual courses of action were proposed.
78

Renewable Energy Market for Rural Electrification in Developing Countries: Country Case Nepal

Mainali, Brijesh January 2011 (has links)
The availability of abundant renewable resources, lack of fossil fuels and difficult geographical terrain for grid line extensions contribute to the advantages of renewable based decentralized rural electrification in Ne-pal. Solar home system (SHS) and micro-hydro are the most commonly adopted off-grid renewable energy technologies in the country. This dis-sertation examines the market of renewable energy based rural electrifi-cation within prevailing policy and programmes framework. The study verifies whether the market has been able to serve the poor in Nepal. It also captures the perception of various stakeholders (e.g. private sup-ply/installation companies, NGOs, financial institutions and the donor‘s programme) regarding the business, financing issues and the role of gov-ernment policy on the market development. In addition, the study dis-cusses and analyses renewable based rural electrification supply models, the economics behind rural electrification, market drivers and market distribution in the rural areas of Nepal. The financial mix in the off-grid rural electrification is generally charac-terized by subsidy, equity and credit. The study shows that awareness about renewable energy technologies and willingness to pay for electricity access has increased considerably. However, there is a huge financial gap between the cost of electrification and affordability among the poor. The distribution analysis shows there is significant increment in the extensive growth but decrease in the intensive growth rate of rural electrification thus indicating market expansion with uneven penetration among the ru-ral people. Solar PV technology is still not in the reach of the economic poor. Access to credit and cumbersome subsidy delivery mechanisms have been perceived as the major factors affecting the expansion of rural electrification by the stakeholders, requiring innovation in the credit and subsidy delivery system so that a larger rural population can be given ac-cess to electrification. / QC 20110502
79

Analysis of Off-grid Energy Systems for Small Villages at Three Different Locations

THOMAS, HARDY, Varkey Alex, Dimal January 2022 (has links)
The development of new communities to facilitate the growing population isan ongoing trend, with locations outside the city limits so as to have morearea and less pollution. The main need in isolated communities is to secureenergy demand, which is normally done with power supply from the maingrid, which will require new transmission lines and transformer installation,among other things. As we strive for net-zero energy buildings, the energysource should be renewable and clean. So far, the most common andefficient renewable sources available in abundance are solar and windpower. So, based on the location, we investigate how we can make thesystem of combined solar, and wind power a successful energy source sothat the load of the community can be fulfilled while at the same time thepower from the main grid is isolated. This analysis is done for off-gridsystems to analyze a combined Solar and Wind energy production andcalculate the needed storage, also presenting a comparison with Dieselbased generation and an Economical perspective,for the different locations.As an output of this analysis a program has been developed to examineother locations on bases of local load data.
80

Earthly Matters of Cosmic Awareness: A 2023 Thesis of Architecture

Mitchell, Henry 05 October 2023 (has links)
Architecture, as a discipline, has the potential to serve as a catalyst for cultivating an awareness of our intrinsic connection to the Earth and the broader universe. However, in the contemporary world, architectural practices frequently tend to alienate us from the natural environment, compelling many of us to inhabit indoor spaces reliant on centralized utility systems. This reliance, in turn, exerts significant stress on the Earth's ecosystems. The essence of architecture should instead lie in its capacity to engage with the surrounding natural elements, including the sun, wind, earth, and rain, thereby prompting individuals to acknowledge their geographical and planetary context. By harnessing these natural forces at the local level, architectural structures could autonomously provide their occupants with essential resources such as energy, water, and sustenance throughout the year. This thesis embarks on an exploration of the feasibility of integrating these principles of passive design into architectural structures, with the overarching goal of imparting experiential learning opportunities to the broader public. Through this endeavor, architecture can transcend its conventional role and emerge as a conduit for disseminating knowledge and awareness about sustainable living practices. Ultimately, this reimagined role for architecture can play a pivotal part in catalyzing the ongoing human evolution towards enhanced health and resilience, both as individuals and as a species. / Master of Architecture / Architecture should make us aware of how we are connected to the earth and by its extension, the universe. In today's world, it often closes us off from nature instead. Many of us are plugged in to an indoor culture that relies on centralized utility infrastructure to sustain, which often puts great strain on the natural environment. By interacting with surrounding natural phenomenon such as the sun, wind, earth, and rain, our buildings should remind us of our geographical and planetary context. By gathering these natural forces local, a building could supply its inhabitants with energy, water, and facilitate food production year round. This thesis aims to explore how a building could demonstrate these principles of passive design to the general public by using architecture as a vessel for experiential learning. This is the role Architecture can play in the process of human evolution towards becoming a healthier and more resilient species.

Page generated in 0.0307 seconds