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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.
231

Performance characteristics and computer modelling of a solar liquid piston pump

Brew-Hammond, J. P. Abeeku. January 1984 (has links)
No description available.
232

Solar food drying in Zambia

Kwendakwema, Nicholas John. January 1983 (has links)
No description available.
233

The study of a double-effect basin type solar still.

Lantagne, Michel January 1971 (has links)
No description available.
234

ULTRAFAST ELECTRON TRANSFER IN BIOMIMETIC SOLAR ENERGY CONVERSION ARCHITECTURES

Henrich, Joseph David 01 November 2010 (has links)
No description available.
235

Feasibility Study of the Utilization of Solar Energy for Large Scale Power Production in the State of Florida

Propen, Michael 01 January 1975 (has links) (PDF)
The objective of this paper is to investigate the feasibility of large scale electric power generation in the state of Florida by means of solar conversion. Such systems convert solar radiation directly to electricity or to thermal energy and subsequently to electricity. With the latter method, solar energy is initially collected and converted to heat at high temperature through a working fluid. The heat is then used to power conventional heat engine generator systems. Several methods have been proposed for converting sunlight to useful work. The most promising of these will be examined from a technological and economic viewpoint.
236

The Social Acceptance of Community Solar: a Portland Case Study

Weaver, Anne 05 September 2017 (has links)
Community solar is a renewable energy practice that's been adopted by multiple U.S. states and is being considered by many more, including the state of Oregon. A recent senate bill in Oregon, called the "Clean Electricity and Coal Transition Plan", includes a provision that directs the Oregon Public Utility Commission to establish a community solar program for investor-owned utilities by late 2017. Thus, energy consumers in Portland will be offered participation in community solar projects in the near future. Community solar is a mechanism that allows ratepayers to experience both the costs and benefits of solar energy while also helping to offset the proportion of fossil-fuel generated electricity in utility grids, thus aiding climate change mitigation. For community solar to achieve market success in the residential sector of Portland, ratepayers of investor-owned utilities must socially accept this energy practice. The aim of this study was to forecast the potential social acceptance of community solar among Portland residents by measuring willingness to participate in these projects. Additionally, consumer characteristics, attitudes, awareness, and knowledge were captured to assess the influence of these factors on intent to enroll in community solar. The theory of planned behavior, as well as the social acceptance, diffusion of innovation, and dual-interest theories were frameworks used to inform the analysis of community solar adoption. These research objectives were addressed through a mixed-mode survey of Portland residents, using a stratified random sample of Portland neighborhoods to acquire a gradient of demographics. 330 questionnaires were completed, yielding a 34.2% response rate. Descriptive statistics, binomial logistic regression models, and mean willingness to pay were the analyses conducted to measure the influence of project factors and demographic characteristics on likelihood of community solar participation. Roughly 60% of respondents exhibited interest in community solar enrollment. The logistic regression model revealed the percent change in utility bill (essentially the rate of return on the community solar investment) as a dramatically influential variable predicting willingness to participate. Community solar project scenarios also had a strong influence on willingness to participate: larger, cheaper, and distant projects were preferred over small and expensive local projects. Results indicate that community solar project features that accentuate affordability are most important to energy consumers. Additionally, demographic characteristics that were strongly correlated with willingness to enroll were politically liberal ideologies, higher incomes, current enrollment in green utility programs, and membership in an environmental organization. Thus, the market acceptance of community solar in Portland will potentially be broadened by emphasizing affordability over other features, such as community and locality. Additionally, I explored attitudinal influences on interest in community solar by conducting exploratory factor analysis on attitudes towards energy, climate change, and solar barriers and subsequently conducting binomial logistic regression models. Results found that perceiving renewable energy as environmentally beneficial was positively correlated with intent to enroll in community solar, which supported the notion that environmental attitudes will lead to environmental behaviors. The logistic regression model also revealed a negative correlation between community solar interest and negative attitudes towards renewable energy. Perceptions of solar barriers were mild, indicating that lack of an enabling mechanism may be the reason solar continues to be underutilized in this region.
237

Solar energy production at Heby Skola : A pilot study of a photovoltaic installation in Sweden

Aronsson, Oscar, Nyqvist, Daniel, Robertsson, Simon January 2013 (has links)
Photovoltaic is a renewable energy technology that creates electricity by converting the energy of light. Photovoltaics are usually installed on buildings. In this pilot study, the viability of such an installation on the roof of the school Heby skola is examined with respect to produced electricity, economic potential and environmental impact. This is done with the software Solelekonomi, together with 11-years of solar irradiance data and measurements of the properties of the intended roof, which made it was possible to simulate the production patterns of a photovoltaic system. The simulations were made on two possible system sizes 50 m2 and 200 m2 with respectively 7.75 and 31 kWpeak installed power. Among other things, the results showed that 1.1% and 4.45% of the total electricity consumption could be replaced by the systems. A PV investment was found to be a good option with respect to the sections examined. Furthermore, considering PVinstallations, the school was found to be representative for schools in Sweden, and thus this essay can provide a basis for other PV pilot project on Swedish schools.
238

Feasibility study of an integrated wind and solar farm by evaluating the wind turbine shadows

Shanghavi, Sahil 10 July 2012 (has links)
This thesis analyzes the feasibility of having an integrated wind and solar farm to optimize the use of land resources and capital investment by evaluating the effect that wind turbine shadows have on the area surrounding them. Two methods are used to predict shadow impact. The first method is based on the traditional textbook “Clear Sky” equations, which have maximum sensitivity to shadows because the method considers every day to be a perfect day. The second method uses measured global-horizontal and diffuse-horizontal solar radiation in units of W/m2, which take into account the true variations of daily conditions. The calculations are performed for 1 square meter surfaces, over different assumed areas of a wind power plant, for every second of the day. For purposes of shadow calculations, the tip-top height (i.e., tower height plus blade length) is used. All calculations are performed with the specifications of a GE 1.5 MW wind turbine, which is the most commonly used wind turbine in USA. / text
239

Examining Solar Energy Policy in China and India. : A Comparative Study on the Potential for Energy Security and Sustainable Development

Kok, Sarah January 2015 (has links)
As living standards improve and population numbers increase in China and India, the demand and consumption of electricity will continue to intensify.  Although both countries maintain a strong dependence on fossil fuels to meet energy demands, a recognition of the importance of a low carbon transition is apparent from the governments of both countries.  China and India have both made commitments to abate global climate change, reduce poverty rates and enhance efforts to reduce fossil fuel dependence.  Solar energy has experienced phenomenal growth in the last twenty years due to technological advances, priced reductions and governmental support policies. Yet in China and India policy development has been very erratic.  This paper takes a case study approach to examine solar energy policies, particularly solar energy auctions, in China and India.  Thus, this thesis aims to examine solar energy policy in China and India, and compare the potential of each country for energy security and sustainable development under the IRENA framework to Evaluate Renewable Energy Policy.  The performance of solar energy policy in China and India is assessed on criteria of effectiveness, efficiency, equity and institutional feasibility.  This study find that China has installed more cumulative solar capacity than India and that overall that solar energy policy in China is stronger than in India.  However, at an individual policy level, India’s solar energy auction policy is stronger than China’s.  Thus, the long-term sustainability of solar energy policy and deployment in both countries is a complex and multifaceted issue.  This thesis concludes that for energy security and sustainable development the continuation of policy support is necessary in both countries to ensure that solar will continue to grow in significance.
240

Temperature and irradiance dependence of dye-sensitized solar cell performance

Peng, Edwin, 1989- 16 February 2011 (has links)
Dye-sensitized solar cells (DSSCs) are photoelectrochemical cells that offer efficient and potentially economical alternative to conventional solar electricity production technologies. DSSCs belong to the third generation of solar cells and offer several advantages over the solid-state junction solar cells. They utilize materials, such as titanium dioxide that are inexpensive and abundant relative to those used in conventional solar cells. Moreover, DSSCs can be fabricated with simple and scalable manufacturing processes. Finally, in DSSCs, photon absorption and charge-carrier transport are undertaken by different materials, namely molecular dyes and wide band gap semiconductors, respectively. Unlike conventional solar cells, no compromise is necessary between decreasing the band gap for visible light absorption and increasing the band gap to resist photocorrosion. For successful commercialization, a photovoltaic system incorporating DSSCs must operate reliably under a wide range of solar irradiance and operating temperatures. This experimental study reports the fabrication and characterization of the performance of a DSSC as a function of irradiance and operating temperature. The prototyped DSSCs had (i) nanocrystalline titanium(IV) dioxide, TiO₂, photoanode, (ii) platinum thin film cathode, and (iii) acetonitrile based liquid electrolyte. The photoanodes were sensitized with N-749 dye. The current-voltage characteristics of the DSSCs were measured at operating temperatures from 5 to 50° C and under 500, 1000, and 1500 W m⁻² irradiance. The open circuit voltage, V[subscript oc], decreased linearly with increasing temperature and had positive, logarithmic relation with irradiance. At temperatures lower than 15° C and 1500 W m⁻² irradiance, short circuit current density, J[subscript sc], was limited by the diffusion of I₃ in the electrolyte and increased with increasing temperature. At temperatures lower than 15° C and lower irradiance, J[subscript sc] increased with increasing temperature due to electron density limited recombination of electrons injected into the TiO₂ conduction band. At higher temperatures, the recombination was dominant over diffusion and J[scubscript sc] decreased with increasing temperature. Moreover, J[subscript sc] increased linearly with increasing irradiance. The DSSC photoconversion efficiency did not vary appreciably at temperatures lower than 15° C but decreased with increasing temperature. Finally, the DSSC efficiency increased with increasing irradiance. There was no indication of significant coupling effect of irradiance and temperature on DSSC efficiency. This study reports for the first time the coupling between irradiance and thermal effects on the operation of DSSCs. The results reported in this study can be used in recovering kinetic and transport properties that can be used in modeling and optimization of DSSCs. / text

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