This paper presents and discusses research conducted with the purpose of developing the use of solar energy in the heat treatment of steels. For this, a vertical axis solar furnace called at... Show moreThis paper presents and discusses research conducted with the purpose of developing the use of solar energy in the heat treatment of steels. For this, a vertical axis solar furnace called at Plataforma Solar de Almeria was adapted such as to allow control of the heating and cooling processes of samples made from1.1730 steel. Thus temperature variation in pre-set points of the heated samples could be monitored incorrelation with the working parameters: the level of solar radiation and implicitly the energy used theconditions of sample exposed to solar radiation, and the various protections and cooling mediums.Therecorded data allowed establishing the types of treatments applied for certain working conditions. Thedistribution of hardness, as the representative feature resulting from heat treatment, was analysed on allsides of the treated samples. In correlation with the time-temperature-transformation diagram of 1.1730steel, the measured values confirmed the possibility of using solar energy in all types of heat treatmentapplied to this steel. In parallel the efficiency of using solar energy was analysed in comparison to the energyobtained by burning methane gas for the heat treatment for the same set of samples. The analysis consideredenergy consumption, productivity and the impact on the environment. Thanks to various data obtainedthrough developed experiences, which cover a wide range of thermic treatments applied steels 1.1730model, we can certainly state that this can be a solid base in using solar energy in applications of thermictreatment at a high industrial level. Show less
This thesis is concerned with the transfer of energy from light to matter. Over a century ago it was established that light consists of packets of energy [1], now known as photons. Not much later... Show moreThis thesis is concerned with the transfer of energy from light to matter. Over a century ago it was established that light consists of packets of energy [1], now known as photons. Not much later the energy levels of matter at the atomic scale were found to be discrete [2]. These phenomena required a new physical description that has become the theory of quantum mechanics [3]. Now, this theory of light and matter could contribute to tackling a fundamental socioeconomic and technological challenge: To find a sustainable supply of useful energy that is cheap, abundant and generated on-the-spot Show less
The main aim of this thesis is to project whether the five North African countries (Algeria, Egypt, Libya, Morocco, and Tunisa) have the potentials to suffer from a solar energy curse. Under the... Show moreThe main aim of this thesis is to project whether the five North African countries (Algeria, Egypt, Libya, Morocco, and Tunisa) have the potentials to suffer from a solar energy curse. Under the assumption that a solar energy curse will be similar to the current resource curse, the combination of the poor institutional quality and the enormous size of resource rents is selected as the cause of the resource curse. Accordingly, the most recent institutional quality of these countries and the projected solar energy rent size are used to identify the possible solar energy curse. Due to the small projected solar energy rent size, it is less likely that the five North African countries will suffer from a solar energy curse. However, it is also found that the successful establishment of the solar energy in the North African energy exporters (Algeria, Egypt, and Libya) can prolong the time for them to rely on their fossil-fuels exports, therefore, prolonging the current resource curse. Furthermore, this thesis finds that the improvement of institutional quality can help them to avoid 'curses' and, more importantly, lead them to sustainable development Show less