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1.
The curbing of greenhouse gases (GHG) is an important issue on the international political agenda. The substitution of fossil fuels by renewable energy sources is an often-advocated mitigation strategy. Wind energy is a potential renewable energy source. However, wind energy is not reliable since its electricity production depends on variable weather conditions. High wind energy penetration rates lead to losses due to power plant operation adjustments to wind energy. This research identifies the potential energetic benefits of integrated hydrogen production in electricity systems with high wind energy penetration. This research concludes that the use of system losses for hydrogen production via electrolysis is beneficial in situations with ca. 8 GW or more wind energy capacity in the Netherlands. The 2020 Dutch policy goal of 6 GW will not benefit from hydrogen production in terms of systems efficiency. An ancillary beneficial effect of coupling hydrogen production with wind energy is to relieve the high-voltage grid.  相似文献   

2.
This paper is focused on a new methodology for the global assessment of wind power potential. Most of the previous works on the global assessment of the technological potential of wind power have used bottom-up methodologies (e.g. 2, 4 and 31). Economic, ecological and other assessments have been developed, based on these technological capacities. However, this paper tries to show that the reported regional and global technological potential are flawed because they do not conserve the energetic balance on Earth, violating the first principle of energy conservation (Gans et al., 2010). We propose a top–down approach, such as that in Miller et al. (2010), to evaluate the physical–geographical potential and, for the first time, to evaluate the global technological wind power potential, while acknowledging energy conservation. The results give roughly 1 TW for the top limit of the future electrical potential of wind energy. This value is much lower than previous estimates and even lower than economic and realizable potentials published for the mid-century (e.g. 8, 10 and 52).  相似文献   

3.
For an economically and ecologically optimised integration of fluctuating renewable power generation (especially wind power) into electricity generation, a detailed consideration of fluctuation-induced effects on the existing power system is essential. A model-based approach is introduced in this paper, which comprehensively analyses the impact of such effects on power plant scheduling and facilitates their integration into the development of strategies for an optimised evolution of the future power system structure. The newly developed Aeolius tool for the simulation of power plant scheduling is described. In a combined analysis of long- and short-term effects it is used together with the multi-periodic cost-optimising energy system model PERSEUS-CERT. Based on the Matlab/Simulink® package, Aeolius considers the challenges for plant scheduling down to a time scale of 10 min. Special attention is paid to the provision of stand-by capacities and control power, as well as intermediate storage. Thus, a sophisticated quantification of the actual (net) benefits of wind power feed-in is achieved. Model results for Germany show that wind mainly substitutes power from intermediate-load and base-load plants (coal-, lignite-, and nuclear-fired). However, the required provision of stand-by capacities and control power does not only limit the substitution of conventional capacities, but also the achievable net savings of fuel and emissions in conventional power generation.  相似文献   

4.
Wind energy has become a major competitor of traditional fossil fuel energy, particularly with the successful operation of multi-megawatt sized wind turbines. However, wind with reasonable speed is not adequately sustainable everywhere to build an economical wind farm. The potential site has to be thoroughly investigated at least with respect to wind speed profile and air density. Wind speed increases with height, thus an increase of the height of turbine rotor leads to more generated power. Therefore, it is imperative to have a precise knowledge of wind speed profiles in order to assess the potential for a wind farm site. This paper proposes a clustering algorithm based neuro-fuzzy method to find wind speed profile up to height of 100 m based on knowledge of wind speed at heights 10, 20, 30, 40 m. The model estimated wind speed at 40 m based on measured data at 10, 20, and 30 m has 3% mean absolute percent error when compared with measured wind speed at height 40 m. This close agreement between estimated and measured wind speed at 40 m indicates the viability of the proposed method. The comparison with the 1/7th law and experimental wind shear method further proofs the suitability of the proposed method for generating wind speed profile based on knowledge of wind speed at lower heights.  相似文献   

5.
This analysis provides time-series data on electric efficiencies for 138 countries and regions, covering all fossil fuels for the period 1971–2005, with an emphasis on non-Organization for Economic Cooperation and Development (OECD) countries. Fossil fuel consumption for electricity generation in non-OECD countries now exceeds that in the OECD. The historical performance of the top five non-OECD consumers of each fossil fuel for which reliable data are available is presented and discussed. For each fuel, the countries that lead the world in efficiency are used for benchmarks; bringing the rest of the world up to these standards would result in energy savings of 26 EJ (equivalent to 5% of global energy consumption) and CO2 emissions reduction of 2.1 Pg (equivalent to 8% of global CO2 emissions). Coal showed the largest potential margin of improvement for both energy and CO2, with possible savings equivalent to 3% of current global energy consumption and 5% of global CO2 emissions. The gap in electric efficiency between OECD and non-OECD countries over the past 35 years has widened for coal-fired generation, stayed relatively constant for natural gas, but has shrunk for petroleum. The results show the very gradual nature of overall efficiency improvements and the significant differences among regions and countries.  相似文献   

6.
Electric motors use major share (i.e. about 30–80% of total industrial energy consumption) of total industrial energy use around the world. Experiences from other countries show that government intervention in the form of regulations such as mandatory and voluntary approaches can save sizeable amount of energy along with the reduction in emissions associated with energy savings. This paper presents potential energy savings by introducing high-efficiency motors as a case study in Malaysian industrial sector. Emission reductions associated with the energy savings has been estimated and presented as well. It was also estimated that a cumulative amount of 1940 and 892 GWh of energy can be saved for 20 and 120 kW motors, respectively, in Malaysia relative to BAU over the next 10 years. Similarly, a cumulative amount of USD 100 million and USD 60 million can be saved as utility bills for the same motor categories. It has been found that the payback period of different capacities of motors are less than a year. Based on results, it was found that 1789 million kg of CO2 emission can be avoided by replacing standard motors with high-efficiency motors.  相似文献   

7.
Usually in islands both primary energy sources and drinking water are missing. Additionally, municipal solid waste (MSW) must be managed avoiding exclusive use of landfills, which limits sustainable development. Power generation from MSW incineration contributes significantly to replacing energy produced from fossil fuels and to reduce overall emissions. A solution based on thermodynamics, environmental and economic analyses and 3D-GIS modelling for the afore-mentioned problems for Cape Verde is proposed. This model integrates waste transportation optimisation and incineration with energy recovery combining production of heat and power (CHP), the heat being used for drinking water production. The results show that extraction condensing steam turbines are more suitable when power production is a priority (5.0 MW with 4000 m3/d of drinking water), whereas back-pressure turbines yield 5540–6650 m3/d of drinking water with an additional power production of 3.3–4.7 MW. The environmental and economic assessment performed shows the feasibility of the proposed CHP solution, which brings a considerable reduction in net air emissions (1.6 kt), including a significant decrease in the greenhouse gas emissions (131 ktCO2), and that the revenue from energy sales (€15 million) has potential to balance the incineration cost. Moreover, when terrain relief is accounted for in the route optimisation for minimum fuel consumption, savings up to 11% are obtained.  相似文献   

8.
Energy conservation potential in Taiwanese textile industry   总被引:1,自引:0,他引:1  
Since Taiwan lacks sufficient self-produced energy, increasing energy efficiency and energy savings are essential aspects of Taiwan’s energy policy. This work summarizes the energy savings implemented by 303 firms in Taiwan’s textile industry from the on-line Energy Declaration System in 2008. It was found that the total implemented energy savings amounted to 46,074 ton of oil equivalent (TOE). The energy saving was equivalent to 94,614 MWh of electricity, 23,686 kl of fuel oil and 4887 ton of fuel coal. It represented a potential reduction of 143,669 ton in carbon dioxide emissions, equivalent to the annual carbon dioxide absorption capacity of a 3848 ha plantation forest. This study summarizes energy-saving measures for energy users and identifies the areas for making energy saving to provide an energy efficiency baseline.  相似文献   

9.
In this study, the potential of wind energy and assessment of wind energy systems in Turkey were studied. The main purpose of this study is to investigate the wind energy potential and future wind conversion systems project in Turkey. The wind energy potential of various regions was investigated; and the exploitation of the wind energy in Turkey was discussed. Various regions were analyzed taking into account the wind data measured as hourly time series in the windy locations. The wind data used in this study were taken from Electrical Power Resources Survey and Development Administration (EIEI) for the year 2010. This paper reviews the assessment of wind energy in Turkey as of the end of May 2010 including wind energy applications. Turkey's total theoretically available potential for wind power is around 131,756.40 MW and sea wind power 17,393.20 MW annually, according to TUREB (TWEA). When Turkey has 1.5 MW nominal installed wind energy capacity in 1998, then this capacity has increased to 1522.20 MW in 2010. Wind power plant with a total capacity of 1522.20 MW will be commissioned 2166.65 MW in December 2011.  相似文献   

10.
Renewable energy represents an area of tremendous opportunity for India. Energy is considered a prime agent in the generation of wealth and a significant factor in economic development. Energy is also essential for improving the quality of life. Development of conventional forms of energy for meeting the growing energy needs of society at a reasonable cost is the responsibility of the Government. Limited fossil resources and associated environmental problems have emphasized the need for new sustainable energy supply options. India depends heavily on coal and oil for meeting its energy demand which contributes to smog, acid rain and greenhouse gases’ emission. Last 25 years has been a period of intense activities related to research, development, production and distribution of energy in India.Though major energy sources for electrical power are coal and natural gas, development and promotion of non-conventional sources of energy such as solar, wind and bio-energy, are also getting sustained attention. The use of electricity has grown since it can be used in variety of applications as well as it can be easily transmitted, the uses of renewable energy like wind and solar is rising. Wind energy is a clean, eco-friendly, renewable resource and is nonpolluting. The gross wind power potential is estimated at around 48,561 MW in the country; a capacity of 14,989.89 MW up to 31st August 2011 has so far been added through wind, which places India in the fifth position globally. This paper discusses the ways in which India has already supported the growth of renewable energy technologies i.e. wind energy and its potential to expand their contribution to world growth in a way that is consistent with world's developmental and environmental goals. The paper presents current status, major achievements and future aspects of wind energy in India.  相似文献   

11.
Egypt is one of the Red Sea and Mediterranean countries having windy enough areas, in particular along the coasts. The coastal location Ras Ghareb on the Red Sea has been investigated in order to know the wind power density available for electricity generation. To account for the wind potential variations with height, a new simple estimating procedure was introduced. This study has explicitly demonstrated the presence of high wind power density nearly 900 kW/m2 per year at 100 m of altitude for this region. Indeed, the seasonal wind powers available are comparable to and sometimes higher than the power density in many European cities for wind electricity applications like Vindeby (Denmark) and also America.New technical analysis for wind turbine characteristics have been made using three types of commercial wind turbines possessing the same rotor diameter and rated power to choice the best wind machine suitable for Ras Ghareb station. As per the decreasing the cut-in wind speed for the wind turbine used, the availability factor increases for a given generator. That it could produce more energy output throughout the year for the location.The aim of this research, was to predict the electrical energy production with the cost analysis of a wind farm 150 MW total power installed at Ras Ghareb area using 100 wind turbines model (Repower MD 77) with 1.5 MW rated power. Additionally, this paper developed the methodology for estimating the price of each kWh electricity from the wind farms. Results show that this wind park will produce maximum energy of 716 GWh/year. The expected specific cost equal to 1.5 € cent/kWh is still less than and very competitive price with that produced from the wind farms in Great Britain and Germany and at the international markets of wind power. The important result derived from this study encourages several wind parks with hundreds of megawatts can be constructed at Ras Ghareb region.  相似文献   

12.
Growing concern in Taiwan has arisen about energy consumption and its adverse environmental impact. The current situation of energy conservation in high energy-consuming industries in Taiwan, including the iron and steel, chemical, cement, pulp and paper, textiles and electric/electrical industries has been presented. Since the energy consumption of the top 100 energy users (T100) comprised over 50% of total industry energy consumption, focusing energy consumption reduction efforts on T100 energy users can achieve significant results. This study conducted on-site energy audits of 314 firms in Taiwan during 2000–2004, and identified potential electricity savings of 1,022,656 MWH, fuel oil savings of 174,643 kiloliters (KL), steam coal savings of 98,620 ton, and natural gas (NG) savings of 10,430 kilo cubic meters. The total potential energy saving thus was 489,505 KL of crude oil equivalent (KLOE), representing a reduction of 1,447,841 ton in the carbon dioxide emissions, equivalent to the annual carbon dioxide absorption capacity of a 39,131-ha plantation forest.  相似文献   

13.
The technical and economic feasibility study of an innovative wind–solar hybrid renewable energy generation system with rainwater collection feature for electrical energy generation is presented in this paper. The power generated would supply part of the energy requirements of the high-rise building where the system is installed. The system integrates and optimizes several green technologies; including urban wind turbine, solar cell module and rain water collector. The design was conceptualized based on the experiences acquired during the development and testing of a suitable wind turbine for Malaysian applications. It is compact and can be built on top of high-rise buildings in order to provide on-site renewable power to the building. It overcomes the inferior aspect on the low wind speed by channeling and increasing the speed of the high altitude free-stream wind through the power-augmentation-guide-vane (PAGV) before it enters the wind turbine at the center portion. The shape or appearance of the PAGV that surrounds the wind turbine can be blended into the building architecture without negative visual impact (becomes part of the building). The design improves the starting behavior of wind turbines. It is also safer to people around and reduces noise pollution. The techno-economic analysis is carried out by applying the life cycle cost (LCC) method. The LCC method takes into consideration the complete range of costs and makes cash flows time-equivalent. The evaluations show that for a system with the PAGV (30 m diameter and 14 m high) and an H-rotor vertical axis wind turbine (17 m diameter and 9 m high) mounted on the top of a 220 m high building, the estimated annual energy savings is 195.2 MW h/year.  相似文献   

14.
Power interruptions are a typical characteristic of national grids in developing countries. Manufacturing, processing, refrigeration and other facilities that require a dependable supply of power, and might be considered a small grid within the larger national grid, employ diesel generators for backup. In this study, we develop a stochastic simulation model of a very small grid connected to an unreliable national grid to show that the introduction of wind-generated power can, despite its intermittency, reduce costs significantly. For a small grid with a peak load of 2.85 MW and diesel generating capacity of 3.75 MW provided by two diesel generators, the savings from using wind energy (based on wind data for Mekelle, Ethiopia) can amount to millions of dollars for a typical July month, or some 5.5–17.5% of total electricity costs. While wind power can lead to significant savings, the variability of wind prevents elimination of the smaller of two diesel units, although this peaking unit operates less frequently than in the absence of wind power.  相似文献   

15.
This paper examines the impacts of wind power generation on the future choice of fuels and technologies in the power sector of Vietnam. The study covers a time frame of 20 yr from 2005 to 2025 and the MARKAL model has been chosen to be adaptable to this specific task. The results of the study show that on a simple cost base, power generated from wind is not yet competitive with that of fossil fuel-based power plants. In order to make wind energy competitive, either carbon tax or an emission reduction target on the system must be imposed. The presence of wind power would affect not only the change in generation mix from coal-based power plants to wind turbines but also an increase in the capacity of other technologies which emit less carbon dioxide. It thus helps reduce fossil fuel requirement and consequently enhances energy security for the country. The study also shows that wind turbine in Vietnam could be a potential CDM project for annex I party countries.  相似文献   

16.
In Tunisian climate, both heating in winter and cooling in summer are required to reach comfort levels. Due to the significant increase in building energy consumption, insulation of external walls is recently applied with a thickness typically ranging between 4 cm and 5 cm regardless of structure and orientation of walls and of economic parameters. In the present study, optimum insulation thickness, energy saving and payback period are calculated for a typical wall structure based on both cooling and heating loads. Yearly transmission loads are rigorously estimated using an analytical method based on Complex Finite Fourier Transform (CFFT). Considering different wall orientations, the west and east facing walls are the least favourite in the cooling season, whereas the north-facing wall is the least favourite in the heating season. A life-cycle cost analysis over a building lifetime of 30 years shows that the south orientation is the most economical with an optimum insulation thickness of 10.1 cm, 71.33% of energy savings and a payback period of 3.29 years. It is noted that wall orientation has a small effect on optimum insulation thickness, but a more significant effect on energy savings which reach a maximum value of 23.78 TND/m2 in the case of east facing wall. A sensitivity analysis shows that economic parameters, such as insulation cost, energy cost, inflation and discount rates and building lifetime, have a noticeable effect on optimum insulation and energy savings. Comparison of the present study with the degree-days model is also performed.  相似文献   

17.
The wind energy potential at four different sites in Ethiopia – Addis Ababa (09:02N, 38:42E), Mekele (13:33N, 39:30E), Nazret (08:32N, 39:22E), and Debrezeit (8:44N, 39:02E) – has been investigated by compiling data from different sources and analyzing it using a software tool. The results relating to wind energy potential are given in terms of the monthly average wind speed, wind speed probability density function (PDF), wind speed cumulative density function (CDF), and wind speed duration curve (DC) for all four selected sites. In brief, for measurements taken at a height of 10 m, the results show that for three of the four locations the wind energy potential is reasonable, with average wind speeds of approximately 4 m/s. For the fourth site, the mean wind speed is less than 3 m/s. This study is the first stage in a longer project and will be followed by an analysis of solar energy potential and finally the design of a hybrid standalone electric energy supply system that includes a wind turbine, PV, diesel generator and battery.  相似文献   

18.
While the dominant role of hydrogen in a sustainable energy future is widely accepted, the strategies for the transition from fossil-based to hydrogen economy are still actively debated. This paper emphasizes the role of carbon-neutral technologies and fuels during the transition period. To satisfy the world's growing appetite for energy and keep our planet healthy, at least 10 TW (or terawatt) of carbon-free power has to be produced by mid-century. Three prominent options discussed in the literature include: decarbonization of fossil energy, nuclear energy and renewable energy sources. These options are analyzed in this paper with a special emphasis on the role of hydrogen as a carbon-free energy carrier. In particular, the authors compare various fossil decarbonization strategies and evaluate the potential of nuclear and renewable energy resources to meet the 10 TW target. An overview of state-of-the-art technologies for production of carbon-free energy carriers and transportation fuels, and the assessment of their commercial potential is provided. It is shown that neither of these three options alone could provide 10 TW of carbon-neutral power without major changes in the existing infrastructure, and/or technological breakthroughs in many areas, and/or a considerable environmental risk. The authors propose a scenario for the transition from current fossil-based to hydrogen economy that includes two key elements: (i) changing the fossil decarbonization strategy from one based on CO2 sequestration to one that involves sequestration and/or utilization of solid carbon, and (ii) producing carbon-neutral synthetic fuels from bio-carbon and hydrogen generated from water using carbon-free sources (nuclear, solar, wind, geothermal). This strategy would allow taking advantage of the existing fuel infrastructure without an adverse environmental impact, and it would secure a smooth carbon-neutral transition from fossil-based to future hydrogen economy.  相似文献   

19.
Egypt is one of the developing countries. The production of electricity in Egypt is basically on petroleum, natural gas, hydro-power and wind energy. The objective of this work to prove the availability of sufficient wind potential in the wide area of deep south Egypt for the operation of wind turbines there. Nevertheless, it gives in general an approximate profile which is useful to the wind parks design for this area. The data used in the calculation are published and analyzed for the first time. The diagrams of the measured wind data for three meteorological stations over a period of two years (wind speed, frequency, direction), wind shear coefficient, the mean monthly and annual wind speed profile for every location are presented. Monthly Weibull parameters, standard deviation and coefficient of variation have been statistically discussed. A comparison of the rose diagrams shows that the wind speed is more persistent and blow over this region of Egypt in two main sectors N and NNW with long duration of frequencies from 67% to 87% over the year with an average wind speed in the range 6.8-7.9 m/s at the three stations. Evaluation of monthly wind energy density at 10 m height by two different methods was carried out. And the final diagram for every site shows no significant difference between them. The annual natural wind energies at 70 m A.G.L. lie between 333 and 377 W/m2 for Dakhla South and Kharga stations, respectively, which is similar to the inland wind potential of Vindeby (Denmark) and some European countries. These results indicate that Kharga and Dakhla South locations are new explored sites for future wind power generation projects.  相似文献   

20.
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