Influence of gamma radiation on spectral photosensitivity of (Si<Subscript>2</Subscript>)<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript> (ZnSe)<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> solid solution

Increase of the photosensitivity of the pSi-n(Si₂)_{1 ? x} (ZnSe) _x (0 ≤ x ≤ 0.01) structure exposed to gamma radiation with photon energy E _ph ≥ 2.3 eV has been demonstrated. It is shown that irradiation with dose up to 10⁴ rad raises and radiation with dose up to 10⁵ rad reduces the forward current of the pSi-n(Si₂)_{1 ? x} (ZnSe) _x structure.     

Fabrication and investigation of ultravialet Au-Zn<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Cd<Subscript>1–<Emphasis Type="Italic">x</Emphasis></Subscript>S-Mo-structures

For the first time fabricated and investigated the photovoltaic characteristics of Au-Zn _x Cd_1–x S-Mofilm structural injection photo detectors sensitive to narrow the ultraviolet region of the electromagnetic spectrum, based on polycrystalline Zn _x Cd_1–x S layers. It was found by adjusting the flow of ZnS and CdS coming to the surface Mo substrate can control the shape of the spectral sensitivity of the Au-Zn _x Cd_1–x S-Mo-film structural injection photo detectors. The results will allow to optimize the structure of photo detectors and solar cells based on polycrystalline thin film solar cells.     

High-efficiency UV photocells based on Zn<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Cd<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript>S solid solutions

A procedure for generating UV photocells in the spectral band Δλ = 350–520 nm with internal amplification is presented. It is revealed that such photocells are characterized by a spectral sensitivity of S _λ ≈ 1.3 A/W at a spectral maximum (λ_max = 461 nm) and by an integral sensitivity of S _int ≈ (25–30) A/lm, which is higher by thousand times than similar parameters of common UV cells. It is shown that photocells based on Zn _x Cd_{1 − x} S solid solutions used as a part of a cascade photo converter make it possible to increase significantly the cascade photo converter efficiency with respect to the existing Si and CdTe photocells.     

Effect of gamma irradiation on photoconductivity and photosensitivity of Si<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript>Sn<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript> solid solutions

The results of studies of the structural feature and the effect of low-dose gamma irradiation (up to 105 rad) on the photoconductivity relaxation and the spectral photosensitivity of pSi-nSi_{1 − x} Sn _x (0 ≤ x ≤ 0.04) structures are described. It is shown that exposure to radiation leads to an increase in the relaxation time constant from 55 to 83 μs and an enhancement in the sensitivity of the structures in the short-wavelength emission spectrum, which is attributed to the radiation-stimulated gettering of crystal lattice defects localized in the near-boundaries regions between Si_{1 −x} Sn _x subcrystallites and Si_{1 − x} Sn _x -Sn and Si_{1 − x} Sn _x -SiO₂ phases.     

Thermodynamic evaluations of solar cooling cogeneration cycle using NaSCN–NH<Subscript>3</Subscript> mixture

The commercial refrigeration and air conditioning consumes more electric power for its operation. The solar vapor absorption refrigeration helps to minimize the electric power usage and it is renewable. Large size of solar collector area is required for producing the standalone power as well as cooling cycle. The integration of power and cooling cycle minimizes the number of components such as heat exchanger, separator and collector area. The main objective of the work is to integrate power and cooling for two outputs with single cycle using NaSCN–NH₃ as working fluid. The advantages of NaSCN–NH₃ are having high pressure and pure ammonia vapor at the exit of the generator. The integrated cycle is made by providing the turbine at the exit of the generator along with superheater. It has three pressures of generator, condensing and sink pressure, which is depending on separator and ambient temperature. At the separator temperature of 150°C with weak solution concentration of 0.30, it produces the cogeneration output of 284.80 kW with cycle and plant thermal efficiency of 0.49 and 0.20 respectively.     

Which factors drive CO<Subscript>2</Subscript> emissions in EU-15? Decomposition and innovative accounting

This study breaks down carbon emissions into six effects within the 15 European Union countries group (EU-15) and analyses their evolution in four distinct periods: 1995–2000 (before European directive 2001/77/EC), 2001–2004 (after European directive 2001/77/EC and before Kyoto), 2005–2007 (after Kyoto implementation), and 2008–2010 (after Kyoto first stage), to determine which of them had more impact in the intensity of emissions. The complete decomposition technique was used to examine the carbon dioxide (CO₂) emissions and its components: carbon intensity (CI effect); changes in fossil fuels consumption towards total energy consumption (EM effect); changes in energy intensity effect (EG effect); the average renewable capacity productivity (GC effect); the change in capacity of renewable energy per capita (CP effect); and the change in population (P effect). It is shown that in the post Kyoto period there is an even greater differential in the negative changes in CO₂ emissions, which were caused by the negative contribution of the intensity variations of the effects EM, GC, CP and P that exceeded the positive changes occurred in CI and EG effects. It is also important to stress the fluctuations in CO₂ variations before and after Kyoto, turning positive changes to negative changes, especially in France, Italy and Spain, revealing the presence of heterogeneity. Moreover, the positive effect of renewable capacity per capita and the negative effect of renewable capacity productivity are the main factors influencing the reduction in CO₂ emissions during the Kyoto first stage. It is possible to infer from the results that one of the ways to reduce emissions intensity will be by increasing the renewable capacity and the productivity in energy generation and consequently through the reduction of the share of the consumption of fossil fuels.     

The composition dependence of the effective thickness of the base layer in Al<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Ga<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript>P/GaP heterophotoconverters

The dependence between the composition of Al _x Ga_{1 − x} P heterophotoconverters and the effective thickness of their base layers was established. An empirical formula to estimate the effective thickness of a base layer as a function of the composition of solid-state solution (0 ≤ x ≤ 0.8) was proposed.     

Situation and measures of China’s CO<Subscript>2</Subscript> emission mitigation after the Paris Agreement

Global response to climate change has entered the phase of full implementation of the Paris Agreement. To control the global temperature rise below 2°C, all countries must make more efforts to reduce emission. China has combined its goal of emission reduction for combating climate change with its domestic sustainable development strategy to promote energy revolution and the transition of economic development to low-carbon patterns. Through reinforcing the commitment and action before 2020, the CO₂ intensity of GDP can decrease by more than 50% by 2020 compared with that of 2005, and the external commitment target of a 40%–45% decrease can be over fulfilled. Currently, under the new economic normal, China further strengthens the policy measure, vigorously saves energy, enhances energy use efficiency and the economic output benefit, and simultaneously develops new and renewable energy and accelerates energy structural decarbonization, so that the annual decrease rate of the CO₂ intensity of GDP keeps a high level of more than 4% and remains increasing. Thus, the decrease rate of the CO₂ intensity of GDP will exceed the GDP growth rate, and then CO₂ emission will peak around 2030. This will promote the fundamental turning of economic development mode, and lay a foundation for the establishment of a sustainable energy system with near-zero emissions and with new and renewable energy as the main body in the second half of this century. China implements the concept of green low-carbon development and accelerates the low carbon transition of energy and economy to achieve win-win results in economic growth and CO₂ emission mitigation, and these policies and actions will also provide experiences for many other developing countries. On the other hand, China will continue to play a positive and constructive leading role in the implementation of the Paris Agreement internationally, and promote the construction of new mechanisms of win-win cooperation, fairness and justice and common development for global climate governance. Moreover, China will make an effort to build a community of common destiny for mankind, promote pragmatic cooperation among countries, especially among developing countries, and take combating climate change as a new development opportunity for jointly moving toward climate-friendly low-carbon economic development path.     

Chemical–mechanical pretreatment of wood: Reducing downsizing energy and increasing enzymatic digestibility

A chemimechanical (CM) pretreatment method was devised, wherein wood chips are acid-treated to weaken the physical structure then disc-refined to produce a fibrous substrate. CM pretreatment was directly compared with a common dilute acid (DA) pretreatment method, wherein wood is mechanically downsized to a powder or fiber substrate and then acid-treated. It was hypothesized that the CM pretreatment sequence would reduce the energy required for size reduction and increase enzymatic digestibility of the pretreated substrate. By treating wood chips in a dilute sulfuric acid liquor before the mechanical downsizing step, the net specific energy (NSE) of disc-refining was reduced by up to 95%. At the optimal acid treatment and disc-refining conditions determined within this work, CM pretreatment could produce a highly digestible lignocellulose substrate (95% cellulose conversion) while requiring less than 100 kWh/tonne od NSE for mechanical downsizing. A comparison of CM and DA pretreated hardwood revealed that CM pretreatment produced a significantly more digestible substrate than DA pretreatment. Differences in the digestibility of CM and DA pretreated substrates were attributed to differences in physical structure. CM pretreatment produced a substrate that consisted primarily of single fibers and small fiber bundles, while DA pretreatment produced larger fiber bundles. Furthermore, the CM pretreated substrate had a more accessible pore structure, and an altered distribution of surface lignin.     

Synthesis of TiO<Subscript>2</Subscript> nanoparticle using sol–gel route and testing its photovoltaic performance in dye-sensitized solar cell

In the present work, sol–gel method is used to synthesize TiO₂ nanoparticle. The characterization of the prepared TiO₂ powder is done using Powder X-ray diffraction (powder XRD), Scanning Electron Microscope (SEM), Energy-Dispersive X-Ray Spectroscopy (EDS) and Ultraviolet-Visible Spectrophotometry (UV-Vis). The XRD pattern reveals formation of anatase phase TiO₂. The SEM images reveal agglomeration of nanoparticles. The absorbance spectrum of TiO₂ nanoparticles was observed with excitonic peaks at 327 nm and the band gap came out to be ~3.2 eV. This prepared TiO₂ was tested for photovoltaic performance by using it in the Dye sensitized solar cell (FTO/TiO₂/N719/KI-I₂/Pt). Conversion of solar light energy to electricity was successfully done using this TiO₂. The fabricated cell showed an open-circuit voltage (V _OC) of 587 mV and short-circuit current density (J _SC) of 5.06 mA/cm². Maximum power (P _max) generated was 1.912 mW/cm² with a fill factor (FF) of 0.644 and a conversion efficiency of 1.91%.     

Influencing households’ energy behaviour—how is this done and on what premises?

This article examines the discourse that the idea of efficiency is built upon according to different actors trying to influence households’ energy behaviour in Sweden. The focus is on information from authorities as well as from interest organisations and energy companies. Information directed to households often contains a strong idea that the individual has to take responsibility for his/her own choices, and that it is through consumer choices the energy system will become more sustainable. The reasons given for changing one's behaviour are motivated both by lower energy costs and a reduced impact on the environment. Common advice for energy reduction is to change to a more energy-efficient apparatus. In this sense efficiency is a way of not changing lifestyle but instead changing technical equipment and user routines. Only the LA21 project questions the need for all the apparatus as well as the possibility to improve existing artifacts, pointing to a need to change our lifestyle. The strong belief in science and technology results in a definition of the problem as a lack of knowledge, where the only solution is to fill this gap.     

How does tax system on energy industries affect energy demand,CO2 emissions,and economy in China?

Energy savings and CO₂ emission reduction have become a major issue in recent years. Taxes on energy production sectors may be an effective way to save energy, reduce CO₂ emissions, and improve environmental quality. This paper constructs a dynamic recursive Computable General Equilibrium (CGE) model to analyze the impact of the energy tax on energy, economy, and environment from the perspective of tax rates and tax forms (specific tax and ad valorem tax). The results show that adjusting the tax system and the tax rate has important implications for energy conservation while having minor impacts on the output of other industries. The impact of an increasing energy tax on the energy demand is greater than the impact on sectoral output, indicating that energy efficiency will be increased to some extent. The CO₂ reduction will increase over time when an ad valorem tax is implemented on enterprises. We found that ad valorem tax has greater elasticity of economic output, energy demand, and CO₂ emission reduction. The results support the direction of China's resource tax reform. However, we argue that it is better to increase the tax rate relatively and relax the control on energy prices so that energy efficiency will increase.     

Energy security and renewable electricity trade—Will Desertec make Europe vulnerable to the “energy weapon”?

Solar power imports to Europe from the deserts of North Africa, as foreseen in the Desertec concept, is one possible way to help decarbonising the European power sector by 2050. However, this approach raises questions of threats to European energy security in such an import scenario, particularly in the light of increasing import dependency and Russia's use of the “energy weapon” in recent years. In this paper we investigate the threat of North African countries using the Desertec electricity exports as an “energy weapon”. We develop and use a new model to assess the interdependence – the bargaining power symmetry, operationalised as costs – of a disruption in a future renewable electricity trade between North Africa and Europe. If Europe maintains current capacity buffers, some demand-response capability and does not import much more than what is described in the Desertec scenario, it is susceptible to extortion and political pressure only if all five exporter countries unite in using the energy weapon. Europe is not vulnerable to extortion by an export cut from only one country, as the European capacity buffers are sufficient to restore the power supply: no single exporter country would have sustained bargaining power over Europe.     

America&#x27;s ‘Achilles Heel’?: Security of US energy infrastructure

America's security may ultimately be more vulnerable to terrorist attacks (as well as technical mishaps or natural disasters) involving its domestic energy supply and particularly its distribution system than as a result of actions of any foreign army. And yet, key energy observers believe that the US energy supply does not need to be insecure, and that it could be made infinitely more secure with a blending of renewable energy, aggressive emphasis on energy efficiency, and the development of a distributed system of energy delivery. Amory B. Lovins, Chief Executive Officer (Research) of the Rocky Mountain Institute (RMI), in Colorado, USA, has been making this case for nearly two decades. He spoke to Don Smith, Refocus magazine recently in Denver, Colorado, about the national importance of viewing energy security in the context of the new world realities.     

Response to: “Evaluating energy efficiency policy: understanding the ‘energy policy epistemology’ may explain the lack of demand for randomized controlled trials,” by Adam Cooper, <Emphasis Type="Italic">Energy Efficiency</Emphasis>, published online 26 January 2018

In January 2018, Adam Cooper (Energy Efficiency, 2018) published a paper that principally responds to a paper by Vine et al. (Energy Efficiency, 7, 627–640, 2014) that makes the case for promoting greater use of experimental research designs, such as randomized controlled trials (RCTs), in the evaluation of energy efficiency policy. Cooper focuses on the barriers that public policy administrators face—arguing that there are alternative, rational reasons why RCTs are not commonly used in energy policy, providing an overlapping but somewhat different “energy policy epistemology” than in Vine (2014).     

Accounting for energy use in China, 1980–94

This study contains quantitative methods to account for national energy use. Based on these models, an analysis has been made of energy consumption, efficiency and savings in China in the period 1980–94. Our study supports the conclusion that the energy efficiency has improved since China's economic reform. However, the statistical system used in China is not sound. Greater attention must be paid to the management of small coal mines.     

Who governs energy? The challenges facing global energy governance

This article conceptualizes the energy problems facing society from a global governance perspective. It argues that a notion of “global energy governance,” taken to mean international collective action efforts undertaken to manage and distribute energy resources and provide energy services, offers a meaningful and useful framework for assessing energy-related challenges. The article begins by exploring the concepts of governance, global governance, and global energy governance. It then examines some of the existing institutions in place to establish and carry out rules and norms governing global energy problems and describes the range of institutional design options available to policymakers. It briefly traces the role of a selection of these institutions, from inter-governmental organizations to summit processes to multilateral development banks to global action networks, in responding to energy issues, and points out their strengths and weaknesses. The article concludes by analyzing how the various approaches to global governance differ in their applicability to addressing the conundrums of global energy problems.     

Fusion energy : An energy source of the future?

With an increasing world population and a growing economy, the demand for energy is sure to grow. The latest predictions for world energy demand all show an upward trend and even with increased energy efficiency we will still need substantially more energy by 2050 than we use today. Where's it to come from? Dr Federico Casci of the European Fusion Development Agreement (EFDA) organisation believes part of the answer is fusion…