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[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] Conductive polymers are macromolecules that have a conjugated system of π bonds. This feature allows the delocalization of electrons through the molecule and generates the possibility of electrical conduction. Among the first reported conductive polymers we find polyacetylene (PA), poly(p-phenylene) (PPP), poly(p-phenylene vinylene) (PPV), polythiophene (PT), polyaniline (PANI) and polypyrrole (PPy). The discovery of the conductive properties of these polymers led to the quest of applications in electronics and in energy generation. In these areas, systems that meet the current technological needs and have a potential use in satisfying future technological requirements have been developed. The objective of this review article is to give an overview of conductive polymers, reviewing some historical data and demonstrating their importance in technological advancement through their application in photovoltaic cells and electronic devices. (author)
[es]Los polimeros conductores son macromoleculas que presentan un sistema conjugado de enlaces π. Este ordenamiento permite la deslocalizacion de electrones a traves de la molecula y genera la posibilidad de conducir electricidad. Entre los primeros polimeros conductores reportados encontramos al poliacetileno (PA), al poli(p-fenileno) (PPP), al poli(fenilenvinileno) (PPV), al politiofeno (PTf), a la polianilina (PANI) y al polipirrol (PPy). El descubrimiento de las propiedades conductoras de estos polimeros condujo a la busqueda de aplicaciones en electronica y en generacion de energia. En estas areas se han desarrollado sistemas que cumplen con las necesidades tecnologicas actuales y que tienen uso potencial, satisfaciendo necesidades tecnologicas futuras. El objetivo del presente articulo de revision es dar una vision general sobre los polimeros conductores, repasando algunos datos historicos y mostrando su importancia para el avance de la tecnologia mediante su aplicacion en celdas fotovoltaicas y dispositivos electronicos. (autor)
[en] Using the generalized formalism of Dalibard, Dupont-Roc and Cohen-Tannoudji we investigate the spontaneous excitation of a static atom interacting with electromagnetic vacuum fluctuations outside an Einstein Gauss-Bonnet black hole in d-dimensions. It shows that spontaneous excitation does not occur in a Boulware vacuum, while exists in an Unruh vacuum and Hartle-Hawking vacuum. As to the total rate of change of the atomic energy, it does not receive the contribution from the coupling constant of the Gauss-Bonnet term at spatial infinity, only the dimensional parameter has the contribution to it. Near the event horizon, both the coupling constant and the dimension p contribute to the total rate of change of the atomic energy in all three kinds of vacuum. We discuss the contribution of the coupling constant and dimensional factor to the results in three different kinds of spacetime lastly. (authors)
[en] Highlights: • Research goal is properties of the electronic ground state of polar molecules. • The electronic structure calculations are performed with CASSCF and MRCI methods. • The large dipole moment of 6Σ+ ground state are achieved at equilibrium bond length. • The present results pave the way towards the further study of polar molecules. Potential energy curves and permanent dipole moments of the 6Σ+ and 8Σ+ ground state of CrX (X = Li, Na, K, Rb and Cs) are calculated by employing the complete active space self-consistent field (CASSCF) and multi-reference configuration interaction (MRCI) methods. The spectroscopic constants for the 6Σ+ and 8Σ+ ground state of these molecules are calculated. Moreover, CrK, CrRb and CrCs molecules with large values of permanent dipole moment (CrK: 5.553 D, CrRb: 6.341 D and CrCs: 6.731 D) at the equilibrium bond distance are potentially interesting candidates for ultracold anisotropic long-range dipole–dipole interactions and many-body physics studies.
[en] The paper presents an innovative way to improve the efficiency of solar energy. The requirements for the two components of the solar cell (the substrate material and the nature of the p-n junction) are determined. The necessity of nanotechnological preparation of the solar cell substrate is shown. The conditions under which technical silicon can be considered as a substrate are determined. A physical picture of the growth process of nanoclusters on the substrate surface based on the fundamental physical effect of self-organization of semiconductor systems is given. The least acceptable parameters of the nanocluster material are determined. The mechanism of the formation process of nanoheterogeneous structure is determined. The special role solar cell nanocomponents is revealed. (authors)
[en] Economic growth is increasing the threat of climate change. It is triggering growth in global energy demand, which increased by 2.1% in 2017, (compared with 0.9% the previous year). This has made it difficult for countries to achieve the Paris 2015 Climate Accord objective to keep the global temperature rise below 2 degrees Celsius in 2050. It is now unclear how governments will be able to announce increased ambitions in line with the goal of holding global warming at 1.5 degrees Celsius in 2050. World Energy Markets Observatory (WEMO) is Capgemini's annual thought leadership and research report that includes useful insights and trends that every energy and utility player should know about as they plan for the future of their business. This 20. edition is drafted mainly from public data combined with Capgemini's expertise in the energy sector. Special expertise on regulation, climate challenges, and customer behavior has been provided by research teams at De Pardieu Brocas Maffei and VaasaETT. The current edition monitors the main indicators of the electricity and gas markets in Europe, North America, Australia, and South-east Asia and reports on developments and transformations in these sectors and addresses six main topics that include: Climate change and regulatory policies, Energy transition, Infrastructure and adequacy of supply, Supply and final customer, Transformation, Financials, Key Findings. Oil prices rose as high as US$80/barrel for the first time since 2014; this represents an increase of nearly 100% since January 2016. Global natural gas demand grew by 3%, thanks in large part to abundant and relatively low-cost supplies. China alone accounted for almost 30% of growth globally. Gas prices rose in Europe, Asia and North America in 2017, but remained below the 10-year average. Despite being the major commodity least loved by analysts, global coal demand rose about 1% in 2017, reversing the trend seen over the last two years. This growth was mainly due to demand in Asia, almost entirely driven by an increase in coal-fired electricity generation. Digital adoption has huge potential to decrease costs in the industry and service sector - among others, IoT and Blockchain witnessed progressive adoption. Grids are strongly impacted by the increased share of intermittent renewables and grid operators will strongly benefit from digitization. However, cyber security still remains a big concern, but this will not prevent utilities from deploying their digital transformation plans.
[en] Over the last two decades, Pakistan’s energy demand has grown exponentially with very diminutive measures taken by the government to fulfill the needs. The large power plant projects are cumbersome, take years to be completed and require plenty of time to get fully operational. The idea of distributed generation works well in this case. Renewable energy comes well into play when we talk about distributed generation but the dependability of renewable energy resources on back-up such as batteries makes them unappealing. The objective of this paper is to practically implement a backup for the renewable energy resources using a mechanical storage such as CAES (Compressed Air Energy System). The proposed model is a composite technology, which comprises of EES (Electrical Energy Storage) and electrical power supply system. Solar energy driven compressor is used to compress the air in a storage tank, which is used on demand to drive the generator coupled air turbine. The fact that the developed system is solar powered, no other fuel is used with air and it uses mechanical storage instead of conventional storage like batteries, which makes the developed prototype system efficient, economical and durable as compared to the existing CAES. This paper focuses on the thermodynamic investigation, design and finally implementing a prototype CAES for a small load as an un-interrupted power supply system. (author)
[en] The 21. annual World Energy Markets Observatory (WEMO) reveals a world struggling to balance the desire for continued economic growth with the need to take deliberate and drastic steps against climate change. In 2018, global energy consumption rose 2.3 percent - nearly twice the average rate since 2010 - as driven by a robust worldwide economy. Despite the rapid growth of renewables in some regions, oil, gas and coal accounted for nearly three-quarters of the increase in total energy demand, their highest share in five years. As a result, greenhouse gas emissions climbed 2 percent globally, a significant break from the plateau of 2014 to 2016. While renewables remain the fastest-growing energy source worldwide, investments during the first half of 2019 declined 14 percent compared with the same period in 2018. Population growth, as well as a lack of anticipated technical breakthroughs over the next two decades, further contribute to a bleak medium- and long-term landscape. This year's WEMO report explores these issues in greater detail and presents new ideas for how utilities, policy-makers and private companies can embrace a long-term strategy that balances growth and change - and draws opportunity from crisis.
[en] Highlights: • Three band systems of KLi observed by polarisation labelling spectroscopy in the UV region. • The molecular constants and potential curves deduced from experimental data. • By comparison with theoretical calculations the states identified as 91Π, 101Π and 111Π. Excitation spectra of KLi molecule were investigated in the spectral range 31,000–33,100 cm−1 by polarisation labelling spectroscopy technique. Three hitherto unknown electronic states of 1Π symmetry were observed. The Dunham coefficients and potential curves characterising the states were deduced from the spectra. Basing on theoretical calculations, the states were identified as 91Π, 101Π and 111Π.