This study investigates the possibilities of applying water generated from the atmosphere for agricultural processes, particularly hydroponic systems. A solar powered, off-grid greenhouse system is proposed as a theoretical solution to food production, in areas affected by water scarcity. Two experiments are conducted with the purpose of testing atmospheric water quality and how it performs in a hydroponic setting. The plausibility of powering said greenhouse system using solar energy is investigated, considering several available solar technologies. Ultimately, the footprint area required to install enough capacity to power the system is discussed, and the potential site of such a system is modelled and visualized. The experiments concluded that atmospheric water is likely suitable for hydroponic use. The study also found that the footprint area required for the greenhouse system probably can be considered reasonable for certain applications, but more research and advances within solar power technology would be beneficial / <p>2021-06-08</p>

Northern regions of Canada are of special interest for renewable energy investment due to the high cost of traditional energy generation in remote communities (Das & Canizares 2016b). However, climate variability and change have a substantial impact on renewable energy yield and system vulnerability (e.g., Ravestein et al. 2018; van der Wiel et al. 2019), and the North will experience more dramatic impacts due to climate change compared with other parts of Canada (Serreze 2015). Using the Canadian Regional Climate Model Version 4 (CanRCM4) large ensemble driven by Representative Concentration Pathway 8.5, current and future wind and solar energy potential, variability and covariability in northern Canada were assessed. Eight focal communities were additionally selected for in-depth analysis based on the work of Das & Canizares (2016b). Robust increases in annual average wind power potential (WPP) are projected across the northernmost part of the study area by 2070-2099 (up to 30%), with changes most pronounced in cold seasons. Decreases in WPP are projected for southern areas. Solar power potential (SPP) is projected to decrease across the study area, with robust changes emerging by as early as 2010-2039. For the focal communities, WPP stability (as measured through inter- and intra-annual variability) is projected to increase, while SPP stability is projected to decrease. The changes in WPP variability are associated with a dampening of the seasonal cycle of WPP in the north. Monthly mean WPP and SPP are negatively correlated, with approximately oppositely-phased seasonal cycles. Combined wind/solar installations therefore show reduced sub-annual variability, stabilizing power supplies relative to installations of solely wind or solar power. Drivers of change in WPP and SPP are complex, but changes in sea ice across the 21st century will play an important role for both WPP and SPP. Over the northern ocean regions, the influence of sea ice loss on roughness length is found to be more important than impacts on surface layer stability. Changes in storm winds also play a role, but impacts due to synoptic storm activity are difficult to distinguish from shifts in the wind speed distribution. Decreases in SPP can be attributed to projected reductions in downwelling shortwave radiation, which in turn are closely associated with changes in cloud characteristics (e.g., optical depth), as measured through CanRCM4 column liquid/ice water content. Clear-sky changes in shortwave radiation were not directly assessed, but are potentially impacted by robust increases in column water vapour. Overall, northern regions of Canada and the focal communities show high potential for renewable energy generation across the 21st century. Projected increases in wind power resources and wind power stability in the focal communities could enhance the cost-savings and emissions reductions predicted based on current climate assessments (e.g., Das & Canizares 2016b). With ever improving technologies and declining costs, the viability of renewable power in the north is likely to become even more certain in years to come. / Graduate

The restoring sources of energy and their development brings the question how these sources can be utilized in the best way. Master`s thesis deals with photovoltaic systems. It describes their history line, actual situation and also brings some expectations in the future. There are mentioned some materials and technologies which are used for its manufacture, conditions of using in practice, advantages and disadvantages and finally a real mobile application of photovoltaic which serves for a production of electricity that is saved in the battery.

Tato diplomová práce analyzuje současnou situaci ve firmě v oblasti projektového řízení při výstavbě solární elektrárny. A pokusí se na základě norem a metodik projektového řízení navrhnout konkrétní kroky, které povedou ve firmě ke zlepšení řízení projektů. Práce je rozdělena do dvou hlavních částí - teoretické a praktické. První část popisuje společnost ZTC Holding SE a zabývá se teoretickými základy řízení projektů, je zde definován management a jeho funkce, řízení projektu, popis projektu, popis činnosti projektového manažera a jeho týmu. V této části je také teorie časové analýzy projektu, včetně metody Critical Path Method (CPM) a Ganttova diagramu. Druhá část se zaměřuje na analýzu vnějšího prostředí pomocí analýzy PESTLE, analýzy SWOT a analýzy vnitřního prostředí 7S. Tato část také pojednává o přesném vymezení projektu, jeho cílů, které jsou definovány metodou SMART. Tato část končí definováním konkrétních rizik, která se mohou vyskytnout během životního cyklu projektu. Závěr diplomové práce je zaměřen na celkové hodnocení navrhovaných postupů, které by měly zlepšit výkonnost ZTC Holding, SE.

The purpose of this dissertation is to design the dual-axis solar tracker carrying the concentrator photovoltaic panels. The preamble of the dissertation shortly examines a photovoltaic cells development up to concentrators and the common support structures of solar power plants. The second part focuses on the engineering process itself. It includes the choice of the variant that suits best the requirements, the calculations of wind load and design of the various joints. The conclusion part is devoted to the evaluation, economy analysis of the construction and proposals for improvements.

Cílem diplomové práce se stane návrh designu solárního pouličního osvětlení, které bude splňovat nároky na design v 21. století. Přípravné analýzy ukáží možné směry, kterými by se měl úspěšný design zvoleného projektu vydat. Průzkum současných projektů existujících ve veřejném prostoru rovněz odhalí hlavní nedostatky stávajících návrhů. Na základě těchto poznatků bude možné přistoupit k tvorbě několika variant designu, ze kterých bude zvolena finální verze. Tato verze bude zpracována dle určených specifikací s ohledem na platné normy pro veřejné osvětlení.

Direct absorption solar collectors offer possible improvement in efficiency over traditional surface absorbing collectors, because they have fewer heat transfer steps and has the ability to utilise higher radiation fluxes. Carbon black based nanofluids, in a base fluid of salt water, were synthesised by a two-step method where the carbon black nanoparticles were treated with a surfactant, TWEEN-20, in a 1:2 mass ratio and sonicated for 60 minutes to break up agglomerates. The synthesised nanofluids showed stability for over 31 days. The different carbon black concentration nanofluids' solar irradiation absorption properties were compared with each other and with the base fluid of salt water in a concentrating, as well as non-concentration scenario. It was found that the carbon black nanofluids showed excellent absorption properties over the entire solar radiation spectrum. A 1 m2 concentrating unit using a two-axis tracking system, with two mirrors and a 1 m diameter circular Fresnel lens, was used to concentrate solar radiation on a direct absorption solar collector flow cell with a 10 cm2 collection area. An optimum concentration of 0.001 volume % carbon black was found to show a 42 % increase in heating rate, compared to that of salt water. The collector was, however, hampered by high energy losses and the maximum collector efficiency achieved was only 46 %, 23 % higher than that of salt water. The overall system efficiency was only 22 %. This low efficiency can be attributed to the high optical concentration losses (50 % - 70 %) present in the concentrating unit. / Dissertation (MEng)--University of Pretoria, 2016. / Chemical Engineering / MEng / Unrestricted

This project examines the initial system analysis and system level design for an integrated elect cal system to be used in a solar powered car. The system design includes the ability to collect and store solar power, as well as manage control signals. The electrical motor for the purposes of this report is considered as part of the mechanical system of the car. The report follows the rigorous systems approach format for as adapted from Blanchard and Fabrycky's Systems Engineering and Analysis 1990). The report begins with a statement of the problem, and continues through preliminary design. / Master of Science

The durability of two solar-selective aluminium titanium oxynitride multilayer coatings was studied under conditions simulating realistic operation of central receiver power plants. The coatings were deposited by cathodic vacuum arc applying an optimized design concept for complete solar-selective coating (SSC) stacks. Compositional, structural and optical characterization of initial and final stacks was performed by scanning electron microscopy, elastic recoil detection, UV-Vis-NIR-IR spectrophotometry and X-Ray diffraction. The design concept of the solar selective coatings was validated by an excellent agreement between simulated and initial experimental stacking order, composition and optical properties. Both SSC stacks were stable in single stage tests of 12 hours at 650°C. At 800°C, they underwent a structural transformation by full oxidation and they lost their solar selectivity. During cyclic durability tests, multilayer 1, comprised of TiN, Al0.64Ti0.36N and an Al1.37Ti0.54O top layer, fulfilled the performance criterion (PC) ≤ 5% for 300 symmetric, 3 hours long cycles at 600°C in air. Multilayer 2, which was constituted of four AlyTi1-y(OxN1-x) layers, met the performance criterion for 250 cycles (750 hours), but was more sensitive to these harsh conditions. With regard to the degradation mechanisms, the coarser microstructure of multilayer 1 is more resistant against oxidation than multilayer 2 with its graded oxygen content. These results confirm that the designed SSCs based on AlyTi1-y(OxN1-x) materials withstand breakdown at 600ºC in air. Therefore, they can be an exciting candidate material for concentrated solar power applications at high temperature.

The transparent conductive oxide (TCO) SnO2:Ta is developed as a selectively solar-transmitting coating for concentrated solar power (CSP) absorbers. Upon covering with an antireflective layer, a calculated absorptivity of 95% and an emissivity of 30% are achieved for the model configuration of SnO2:Ta on top of a perfect black body (BB). High-temperature stability of the developed TCO up to 1073 K is shown in situ by spectroscopic ellipsometry and Rutherford backscattering spectrometry. The universality of the concept is demonstrated by transforming silicon and glassy carbon from non-selective into solar-selective absorbers by depositing the TCO on top of them. Finally, the energy conversion efficiencies of SnO2:Ta on top of a BB and an ideal non-selective BB absorber are extensively compared as a function of solar concentration factor C and absorber temperature TH. Equal CSP efficiencies can be achieved by the TCO on BB configuration with approximately 50% lower solar concentration. This improvement could be used to reduce the number of mirrors in a solar plant, and thus, the levelized costs of electricity for CSP technology.