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The energy balance of the black liquor gasification (BLG) system, which is the core part in the Pulp-Syngas-Heat and Electricity combined cycle system, was analysed in this paper. Based on existing engineering parameters, we compared the energy consumption, conversion efficiency and energy cost of the BLG system under the different process conditions, in particular the air separation and concentration sections. Comparative analysis of these critical processes would facilitate the optimization of energy conversion efficiency and energy cost, as well as ascertain the influence of electricity and heat price on them. Results showed the drive combination of mechanical vapour recompression concentrating black liquor and electric driven preparation of oxygen (MVR-Motor) had the highest energy conversion efficiency of 73.18% but maximal energy cost. The drive combination of multi-effect evaporation concentrating black liquor and back pressure steam turbine preparation of oxygen (MEE-BPST) had the lowest energy cost, despite its energy conversion efficiency a little lower than MVR-Motor. For the drive combination of MVR-Motor, BLG system can get 224.32 kgce net energy output per 1000 kg straw pulp. Selection of reasonable process technology would promote the commercialization of BLG and the links to paper industry, biomass energy industry, and chemical industry, which benefits the control of black liquor pollution. [ABSTRACT FROM AUTHOR]

Tibet is located in the southwest of China, with unique geographical conditions and natural resources, new energy reserves like solar energy and wind resources are in the forefront of other provinces in China, and it is also one of the solar energy resource richest regions in the world. Since central Tibet is the economic center of the Tibet autonomous region and Lhasa is the outside sending end of Qinghai-Tibet DC, developing new energy resources in central Tibet would play an important role in inter-provincial delivery of renewable energy power generation, reducing fossil energy consumption to achieve a clean alternative and stimulating the economic growth of Tibet. In this paper, the renewable energy consumptive situation in central Tibet was studied. Through the analysis of renewable energy reserves, distribution and utilization, the current situation of the renewable energy development and the electricity load in Tibet, the solutions and suggestions for new energy generation consumption were put forward in the end. [ABSTRACT FROM AUTHOR]

With continuous global revolution toward the creation of a green environment, it is ardently necessary to eliminate all possible scopes of energy waste and leakage during the standby or inactive mode of operation. The magnitude of standby energy loss happening in all kinds of electronic and electrical systems is a global concern for scientists and engineers. A global picture of standby power consumption and reduction effort is elaborated in this paper. Approximate charts of standby power loss in majority of the electrical and electronic appliances are tabulated here. Numerous sources of energy losses in standby modes are identified in this paper. Some illustrations are made regarding the technical steps to be adhered to minimize the inactive mode power consumption. Power supplies that are the major contributors of energy waste are identified here. Various procedures and approaches are suggested, which would lead to standby power reduction and thereby would produce mode energy efficient systems. These corrective measures if properly implemented universally in both domestic as well as industrial appliances would save immense energy count and hence would reduce the global demand of energy. [ABSTRACT FROM AUTHOR]

Given the rapid increase of residential energy consumption in Beijing, the question of how to promote residential energy-saving behavior is an emerging topic that is increasingly engaging the attention of scholars. To address this issue, this paper provides an empirical analysis that identifies and explores the determinants of an energy-saving behavioral intention among residents from the perspective of the theory of planned behavior (TPB). A theoretical model was constructed by refining and extending the classic TPB model according to the scope and requirements of this study and the existing situation in China. Survey data collected from 276 residents in Beijing were analyzed, and hypothesized relationships in the model were then verified using a structural equation model. The results show that subjective norms, environmental attitudes, information publicity, lifestyles, and perceived behavioral control significantly influence residents' energy-saving behavior, while demographic factors, such as educational background, household income, and age, had no obvious effects on behavioral intentions. Although knowledge regarding energy did not exert a direct influence on residents' energy-saving behavioral intentions, it did exert an indirect influence via environmental attitudes. Our results indicate that the role of households in saving energy expenditure should be emphasized, and financial incentives could be adopted to help promote environmental awareness among Beijing's residents. In addition, environment-friendly and energy-saving habits should also be inculcated. [ABSTRACT FROM AUTHOR]

To compensate for the limitation of the energy intensity indicator and to constrain energy consumption growth more directly and severely, China had decided to implement the Total Energy Consumption Control (TECC) policy during the 12th Five-Year Plan (FYP). This paper analyzes the situation of energy consumption in 3 scenarios based on the energy consumption trend during the 11th FYP, the energy intensity reduction target during the 12th FYP, and the TECC policy. The Energy Conservation Comprehensive Evaluation System (ECCES) which includes 5 indicators reflecting energy conservation responsibility and 3 indicators reflecting energy conservation difficulty has been built, and Analytic Hierarchy Process (AHP) and Entropy methods are used to determine the weights of 8 basic indicators. According to the ranking of comprehensive evaluation scores of ECCES, 30 provinces are divided into 5 clusters, which are assigned 3%, 3.5%, 4.2%, 5.5%, and 6.8% of controlled energy consumption growth rate, respectively. By comparing and analyzing energy consumption situations in 3 scenarios, we find that the TECC policy has the strongest constraint effect, and can achieve unification of provincial and national energy conservation goals. The provincial decomposition result of energy consumption controlled target of TECC policy roughly remains consistent with the current economic and energy development layout of China that the provinces in southeast coastal developed areas are assigned lower controlled energy consumption growth rate while the backward inland provinces are assigned higher growth rates. [ABSTRACT FROM AUTHOR]

To make renewable Micro-Grid (MG) systems work as a sustainable set, one confronts a multi-objective, multi-constraint problem. To optimally operate these hybrid energy systems, one should consider the problems due to huge amount of raw data achieved through several measuring systems in different sections in a MG. In this paper, a new Smart Energy Management System (SEMS) is proposed and tested via simulation studies. The proposed SEMS performs some critical tasks such as data acquisition, data processing, and determining control signals for the MG. Two objective functions are defined for the SEMS to minimize the total operating cost and the net emission of the fossil fueled Distributed Generators with respect to some technical and reliability (Expected Energy Not Supplied index) constraints for the MG. The simulation results show a promising performance of the proposed SEMS for smart micro-grids. [ABSTRACT FROM AUTHOR]

Currently, energy-saving and carbon dioxide reduction are the most critical issues faced by the globe. Therefore, solar energy should be used as much as possible. A possible use is to illuminate a solar cell so as to transform light energy directly into electricity. However, due to its low efficiency and high cost, the solar cell is not presently economically feasible. Utilization of solar energy, which is considered one of the most important renewable energy sources, not only reduces consumption of fossil fuel but also slows down the pace of global warming. In addition to the use of solar cells, daylight illumination is also an important access to solar energy. Our team has developed a technique that can guide the natural light to the interior for indoor illumination. It is called the 'Natural Light Guiding System.' Our system can guide sunlight to the interior, but the distribution of light at the exit of the system is disordered. To solve this problem, we have proposed an optical coupling transmission structure with right-angled prism collecting modules. We analyzed the mathematical model of coupling transmission. And, we also analyzed the efficiency of this cascade structure at the exit surface of the concentrator. In this paper, we provide a high efficiency new concentrator coupled to a transmission device. We save 75% of the optical fiber cable expense usage and we improve efficiency by 47.46% when we add an optical coupling transmission structure to our static lighting concentrator. It is better than the original cascade prism static concentrator. Taking the fiber cost into consideration, we defined a key performance index-it is a ratio of luminous flux on an illuminated area. Our system can provide more powerful light for indoor illumination than existing methods The optical coupling can provide high transmission efficiency and provide parallel light beams at the export from the optical coupling module. We used optical simulation tools to design and simulate the efficiency of the active module. We can use this system as an ecological illumination system to offer steady illumination in indoor space to provide healthy illumination, save energy, and meet safety requirements. [ABSTRACT FROM AUTHOR]

Globally, buildings are responsible for approximately 40% of the total world annual energy consumption. Most of this energy is for the provision of lighting, heating, cooling, and air conditioning. Increasing awareness of the environmental impact of CO2 and NOx emissions and chlorofluorocarbons triggered a renewed interest in environmentally friendly cooling and heating technologies. Under the 1997 Montreal Protocol, governments agreed to phase out chemicals used as refrigerants that have the potential to destroy stratospheric ozone. It was therefore considered desirable to reduce energy consumption and decrease the rate of depletion of world energy reserves and pollution of the environment. One way of reducing building energy consumption is to design buildings that are more economical in their use of energy for heating, lighting, cooling, ventilation, and hot water supply. Passive measures, particularly natural or hybrid ventilation rather than air conditioning, can dramatically reduce primary energy consumption. However, exploitation of renewable energy in buildings and agricultural greenhouses can also significantly contribute toward reducing dependency on fossil fuels. Therefore, promoting innovative renewable applications and reinforcing the renewable energy market will contribute to preservation of the ecosystem by reducing emissions at local and global levels. This will also contribute to the amelioration of environmental conditions by replacing conventional fuels with renewable energies that produce no air pollution or greenhouse gases. The provision of good indoor environmental quality (IEQ) while achieving energy and cost efficient operation of the heating, ventilating, and air-conditioning plants in buildings represents a multivariant problem. The comfort of building occupants is dependent on many environmental parameters including air speed, temperature, relative humidity, and quality in addition to lighting and noise. The overall objective is to provide a high level of building performance, which can be defined as IEQ, energy efficiency (EE), and cost efficiency (CE). IEQ is the perceived condition of comfort that building occupants experience due to the physical and psychological conditions to which they are exposed by their surroundings. The main physical parameters affecting IEQ are air speed, temperature, relative humidity, and quality. EE is related to the provision of the desired environmental conditions while consuming the minimal quantity of energy. CE is the financial expenditure on energy relative to the level of environmental comfort and productivity that the building occupants attained. The overall CE can be improved by improving the IEQ and the EE of a building. The increased availability of reliable and efficient energy services stimulates new development alternatives. Anticipated patterns of future energy use and consequent environmental impacts (acid precipitation, ozone depletion, and greenhouse effect or global warming) are comprehensively discussed in this paper. Throughout the theme several issues relating to renewable energies, environment, and sustainable development are exam-ined from both current and future perspectives. It is concluded that renewable environmentally friendly energy must be encouraged, promoted, implemented, and demonstrated by full-scale plant especially for use in remote rural areas. [ABSTRACT FROM AUTHOR]

This paper is concerned with the study of the Cauchy problem associated with an n-dimensional generalized Benney-Luke equation, utt-mΔu-Δutt+Δ2u+α(2∇u·∇ut+utΔu)+β∇(|∇u|p∇u)=0, where n=1,2,3,4. We prove the existence and the uniqueness of the global solution of the Cauchy problem for the β≼0 case by using energy conservation law and give the existence and the nonexistence of the global solution of the Cauchy problem for the β>0 case by constructing the stable set and the unstable set. [ABSTRACT FROM AUTHOR]

In this paper, a robotic fish with a caudal fin with vertical phase differences is studied, especially focusing on the energy consumption. Energies for thrusting a conventional robotic fish and one with caudal fin with vertical phase differences are obtained and compared each other. It is shown that a robotic fish with a caudal fin with vertical phase differences can save more energy, which implies the efficient thrusting via a vertically waving caudal fin. [ABSTRACT FROM AUTHOR]

With rising energy costs and cuts in expenditures, institutions around the country are trying to find ways to cut energy consumption and operational costs. As many academic institutions have old buildings in service, one of the most considered and relatively easy energy saving alternatives is to change old and inefficient lighting to those that are newer and more energy efficient. This paper deals with the cost savings question of re-lamping existing buildings on the campus of the University of Illinois at Urbana-Champaign using life cycle cost procedures. We examined the energy and costs savings potential by comparing existing prevalent T12 fluorescent lighting fixtures to two T8 fixtures and two T5 fixtures. The results show that, although there may be energy savings potential for some of these newer systems, the economic benefits are not always obvious or real. [ABSTRACT FROM AUTHOR]