Results 1 - 10 of 2823
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[en] Under the current macro-economic trends, the so far abundant support system for renewables (mainly in the form of feed-in-tariffs and quota systems) has been drastically modified. In many EU countries, companies are trying to find alternative ways to secure financing for their renewable energy projects. Therefore, new ways of attracting private capital for the realisation of green energy goals have to replace the old schemes. Some new forms of financing are coming together with the EU Cohesion Policy 2014-2020 (project guarantees, packaging of small project for micro-financing schemes at the regional level, preferential loan instead of subsidies etc.). Advanced financial structures are likely to play an increasingly important role in the allocation of risk and reward among different investor classes. The finance and investment gap needs to be filled by the private sector. The challenge is to identify the appropriate policy options and financial tools to attract and scale-up private investments. There are, however, already innovative and promising business and financial models to promote the deployment of RES in the EU. The aim of the EurObserv'ER case studies is to find such examples and describe them so as to put forward the best practices and the replicability of the future promising financing mechanisms. EurObserv'ER will aim at choosing only the most promising ones and try to describe them in order to promote replicability in other geographical areas. The selection criteria for the choice of case studies should ensure (i) diversity across regions and RES, (ii) diversity across finance instruments/mechanisms, (iii) success of approach and its potential to be replicated, (iv) and a wide range of the 'size' of actors/ investors and the resulting RES investments (capacity). The current selection also takes into account the fact that there were already some case studies published in 2014, 2015, 2018 and 2019. These are also available for download on the project web site: www.eurobserv-er.org
[en] Recent advances in science and technology of materials fabrication, engineering of work functions, and micrometer gap machining between emitter and collector are making thermionic conversion/converter (TEC) of solar energy an emerging technology. As the converter is the lightest of all devices with highest direct power conversion density (per unit area of the converting surface), it has, potential for substituting photovoltaic technology to a large extent and for deployment in space as a power source. This article summarizes the current efforts/technologies in the field, and discusses their inherent merits and demerits towards realizing the goal of achieving high conversion efficiency and simulation of performance evaluation of a solar TEC. We also discuss the use of both metals and nanomaterials, critical roles of work functions of both emitter and collector, collector temperature, absorptivity and emissivity of the surfaces, radiation losses, and use of both metals and nanomaterials in the efficiency of conversion of solar energy. We further deal with the role of correcting thermionic emission current density equation in the simulation of solar TEC performance. We discuss briefly the possible methods of space-charge control in future in a solar TEC. (author)
[en] This WEMO edition reviews an exceptional period with two distinctive phases: - In 2019 worldwide economic slowdown combined with energy transition measures resulted in some improvements regarding climate change objectives. However, the world was not on track to meet the 2015 Paris agreement objectives. - In 2020 our planet suffered from the COVID-19 pandemic and the economic crisis that followed, plunging our world into a long period of uncertainty. This year's World Energy Markets Observatory report explores how the energy sector can balance these competing priorities. Here we present practical ideas for how utilities, policy-makers and private companies can embrace a strategy that builds short-term resiliency while improving long-term sustainability.
[en] Factors affecting Nuclear adoption: 1. Social Acceptance / Risk perception; 2. “Decision to Commissioning” time; 3. Implementation Risk; 4. Load Following capabilities 5.; Decentralization
[en] The influence of real operating conditions of the solar modules (solar radiation intensity, ambient temperature, wind speed) on their output performances is analyzed. An analytical expression is proposed, allowing to approximate the temperature of the solar modules. An algorithm for assessing the operating power of solar modules based on their data sheet information has been developed. The MatLab-Simulink simulation has shown that the identification of ambient and solar module temperatures leads to errors of up to 20 percent in estimating the operating power of solar modules
[en] Photovoltaic effect or phenomenon is the creation of a voltage and corresponding current in a material upon exposure to light energy following the principle that for every excitation there must be a response. The exposition of a solar cell to incident optical radiation excites the dislodgement of electrons hence the creation of holes and subsequent migration of opposite charges. The amount of voltage that can be generated is a function of the intensity of incident optical radiation and the position of the solar cell to such radiation. Measurements of illumination intensity from halogen and tungsten lamps by a digital lux meter and open circuit voltage, short circuit current as output parameters by volt- amp meter LCD display embedded in the solar power device was carried out. The evaluation of fill factor, maximum power and conversion efficiency as other output parameters in relation to illumination from the sources of light at varying angle and distance were carried out in this study also. The variation of the internal resistance of the cell with light intensity was also investigated. The maximum output voltage and current were realized at angle zero degree when the light ray falls at normal to the cell surface. The two 10 Watts halogen lamp gave the highest illumination intensity of 116lx while the 40 Watt and 60 Watt tungsten lamp placed at 10 cm from the solar cell indicated an intensity of 70lx and 25lx each. The results showed the strongly direct dependency of these parameters on illumination intensity and their inverse dependence on the tilt angle and distance of the illumination source. The internal resistance decreases with increasing intensity while the evaluated fill factor, maximum power and efficiency remain fairly constant but at an average value 0.53, 122mW and 55% respectively. (author)
[en] After some brief recalls of definitions (surface and deep geothermal energy), indications of some operational characteristics (high and low energy geothermal, heat pumps), indications of the various fields of application of these different approaches and techniques, indications of some key data (turnover, production, potential), this publication proposes an overview of the various assets of this sector: a local, available, performing, and clean energy, a structured sector. It outlines the essential role of geothermal energy in reaching the objectives of the law on energy transition, but also that the development rate is still insufficient to reach the objectives defined for 2023. Then, measures and actions are proposed to free the whole potential of the geothermal energy sectors.
[en] At a time when the world is facing global warming and the burden on natural resources is increasing. Now, the world is switching towards cleaner form of energies. Renewable solar roof top is one of them. Most developed economies of the world have started their solar programmes by targeting household rooftops. Solar power has reached grid parity and is the cheapest source of distributed power across the world
[en] A formal analogy between the Friedmann equation of relativistic cosmology and models of convective–radiative cooling/heating of a body (including Newton’s, Dulong-Petit’s, Newton-Stefan’s laws, and a generalization) is discussed. The analogy highlights Lagrangians, symmetries, and mathematical properties of the solutions of these cooling laws.
[en] World energy demand is increasing and non-renewable resources are decreasing by exponentially putting a huge burden on the energy sector specifically on the oil and gas industry. To overcome these challenges, renewable energy is the best option with production optimization in the oil and gas sector. However, among all renewable energies, geothermal is the most suitable energy due to its sustainability and presence around the clock. Moreover, there are three types of wells for harnessing geothermal energy such as: producing oil and gas well, abandoned oil and gas wells and geopressured brine well with dissolved gas. In this research study, the author’s considers the technical aspects of electricity generation through oil and gas wells. The power capacity of these wells is determined by the production rate of the well mass flow (m) and temperature (T) of these wells. The main factors that control the wellhead temperature are mass flow rate and formation temperature. Our assessment of gas-producing well in the Kandhkot region showed the wellhead temperature of the produced fluid is too low, compared to ambient temperature for commercial generation of geothermal power. In our work, a conceptual design system to produce power from produced gas by using Solid Works Software is proposed and we have found some positive results. Seven well from the Kandhkot gas field were selected with different mass flow rates and negligible wellhead temperature difference. Author’s found the minimum power net output 21kW at the gas mass flow rate of 0.098504 kg/s with 7.5% thermal efficiency and maximum net output 27.5 kW at gas mass flow rate of 4.102524 kg/s with 10% thermal efficiency. The overall net output power produced from seven well is 174kW and can supply to local communities. (author)