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[en] Researches conducted by Batan's researchers have resulted in a number competences that can be used to produce goods and services, which will be applied to industrial sector. However, there are difficulties how to convey and utilize the R and D products into industrial sector. Evaluation results show that each research result should be completed with techno-economy analysis to obtain the feasibility of a product for industry. Further analysis on multy-product concept, in which one business can produce many main products, will be done. For this purpose, a software package simulating techno-economy I economic feasibility which uses deterministic and stochastic data (Monte Carlo method) was been carried out for multi-product including side product. The programming language used in Visual Basic Studio Net 2003 and SQL as data base processing software. This software applied sensitivity test to identify which investment criteria is sensitive for the prospective businesses. Performance test (trial test) has been conducted and the results are in line with the design requirement, such as investment feasibility and sensitivity displayed deterministically and stochastically. These result can be interpreted very well to support business decision. Validation has been performed using Microsoft Excel (for single product). The result of the trial test and validation show that this package is suitable for demands and is ready for use. (author)
[en] Energy is certainly one of the primary sectors subjected to prospective analysis. Considering that world energy production is essentially based on fossil fuels, it is imperative that humanity uncovers new options and solutions. However, alternative energies remain underdeveloped, mainly because of their investment cost, but also because traditional energy represents an important source of income for certain companies and governments. In this article, Francis Perrin analyses global energy trends throughout the next decades (rise of the emerging countries' consumption, use of renewable energies and unconventional gas) and their impact on the energy market, the planet and in international relations
[en] Gasification is a thermochemical transformation of solid fuel by partial oxidation into synthesis gas comprising of mainly carbon monoxide and hydrogen. Use of this syngas as fuel for gas turbines to generate electricity has enhanced the environmental acceptability of coal gasification. In this work a rigorous model of Coal gasification unit has been developed using the Gibbs free energy minimum method in the RGibbs model. RGibbs models the gasification and combustion reaction neglecting the hydrodynamics complexity of the gasifier. The devolatilization-pyrolsis stage is modeled using RYield model. RGibbs model determines the equilibrium composition of the products resulting from the many reactions that can occur. The influence of operating conditions (temperature and feed composition) on gasifier performance is investigated. The proposed gasification model improves the understanding of the process and can be used as a predictive tool at the optimization stage. ASPEN Plus is used as the simulation tool because it includes physical property models useful in solids handling. (author)
[en] Concern for the environment has been steadily growing in recent years, and it is becoming more common to include environmental impact and pollution costs in the design problem along with construction, investment and operating costs. To economically respond to the global environmental problems ahead, progress must be made both on more sustainable technologies and on the design methodology, which needs to adopt a more holistic approach. Heat pumps and, in particular systems integrating heat pumps and cogeneration units, offer a significant potential for greenhouse gas reduction. This paper illustrates the application of a multi-objective and multi-modal evolutionary algorithm to facilitate the design and planning of a district heating network based on a combination of centralized and decentralized heat pumps combined with on-site cogeneration. Comparisons are made with an earlier study based on a single objective environomic optimisation of the same overall model.
[en] This paper reports on the evaluation of the effectiveness of an energy efficiency program in eastern North Carolina. This subject program is focused on improved construction methods for residential housing. The program incorporates proven energy saving technologies, construction procedures, onsite inspections, and design construction methodologies in new residential construction. The analysis compared the energy usage associated with the houses built in conjunction with the energy efficiency program (test group) with similar new residential construction unrelated to the program (control group). Several statistical methods were employed to establish differences between the energy efficiency program participants and the control group. The analysis provides significant support for the effectiveness of this energy efficiency program and supports the suitability of similar efforts for inclusion in plans for renewable energy offsets and energy efficiency standards.
[en] Micro-generators have the potential to reduce carbon emissions and enhance energy security by providing heat or electricity either from renewable sources, or via the more efficient use of fossil fuels. Such potential is often, however, unquantified or unclear, and hence a thermodynamic and related carbon analysis of micro-generators for UK household energy supply has been performed. Where pertinent, the thermodynamic concept of exergy is employed alongside that of energy. Analysis begins with a description of the established methods of energy supply to, and use within, typical UK households. On these foundations a grid-tied micro-wind turbine, a grid-tied solar photovoltaic array, and a solar hot-water system are analysed. Annual outputs are estimated and contextualised against the demands of representative households. The annual energy-resource and carbon savings provided by the micro-generators are determined on the basis that they (partially) displace the established supply systems. Savings are then compared with the energy-resource and carbon-emission 'debts' of the micro-generators, to assess the latter's net performance. Given appropriate installations, all three micro-generators are found to provide significant net energy and carbon benefits, confirming that all three technologies can provide net reductions in both carbon emissions and dependence on conventional energy resources.
[en] The emission parameters and expose-response functions of some pollutants, such as sulphur dioxide (SO2) and Inhalable Particulate Matter (PM10), were introduced to calculate the emission caused by energy consumption in various sectors and regions in China under different scenarios. The impacts of economic growth, population, and technology progress on energy consumption and on the environment were also analyzed. Finally, the economic value of public health damage caused by the changes of pollutants' concentration related to energy consumption under various scenarios, different regions and sectors in China was analyzed. The results show that the PM-10 and SO2 emissions and consequent health damage will increase significantly in the next 12 years. Thus, energy efficiency, population, economy, and urbanization are the main factors to be considered in this system.
[en] This paper analyses the reduction in greenhouse gas emissions in 15 countries of the European Union between 1990 and 2007 to find out the contribution of different countries. Using the log-mean Divisia index decomposition approach, it identifies the driving factors of emissions related to energy and other industrial activities. It also focuses on two success cases (namely Germany and the United Kingdom) and contrasts the developments with two less successful cases (namely Spain and Italy). A scenario analysis is then used to indicate the emission reduction possibility through cross-learning. The study shows that the emission intensity has reduced significantly in both energy-related activities and other processes at the aggregate level, while the performance varies significantly at the individual country level. Changes in the energy mix, a reduction in energy intensity and a reduction in the emission intensity from other process-related emissions were mainly responsible for the success in the EU-15.
[en] Carbon capture and storage in geological formations has potential risks in the long-term safety because of the possibility of CO2 leakage. Effects of leaking gas, therefore, on vegetation, soil, and soil-inhabiting organisms are critical to understand. An artificial soil gassing and response detection field facility developed at the University of Nottingham was used to inject CO2 gas at a controlled flow rate (1 l min-1) into soil to simulate build-up of soil CO2 concentrations and surface fluxes from two land use types: pasture grassland, and fallow followed by winter bean. Mean soil CO2 concentrations was significantly higher in gassed pasture plots than in gassed fallow plots. Germination of winter bean sown in gassed fallow plots was severely hindered and the final crop stand was reduced to half. Pasture grass showed stress symptoms and above-ground biomass was significantly reduced compared to control plot. A negative correlation (r = -0.95) between soil CO2 and O2 concentrations indicated that injected CO2 displaced O2 from soil. Gassing CO2 reduced soil pH both in grass and fallow plots (p = 0.012). The number of earthworm castings was twice as much in gassed plots than in control plots. This study showed adverse effects of CO2 gas on agro-ecosystem in case of leakage from storage sites to surface.
[en] In transmission and distribution systems, the high number of installed transformers, a loss source in networks, suggests a good potential for energy savings. This paper presents how the Spanish Distribution regulation policy, Royal Decree 222/2008, affects the overall energy efficiency in distribution transformers. The objective of a utility is the maximization of the benefit, and in case of failures, to install a chosen transformer in order to maximize the profit. Here, a novel method to optimize energy efficiency, considering the constraints set by the Spanish Distribution regulation policy, is presented; its aim is to achieve the objectives of the utility when installing new transformers. The overall energy efficiency increase is a clear result that can help in meeting the requirements of European environmental plans, such as the '20-20-20' action plan.