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1.
The climate change issue includes meeting the growing demand for electricity while reducing the impacts from energy sources. Applying carbon capture and storage technology to fossil fuel energy and increasing renewable energy pose greater challenges than increasing nuclear energy. International Energy Agency's (IEA) electricity demand of 30 000 TWh by 2030 can be met with 10 000 TWh each from renewable, nuclear and fossil fuel energy. However, the ill-imposed very strict control of tiny public exposure to ionising radiation from nuclear energy continues to pose a serious hindrance. Effort needs to be re-balanced to produce an even-handed control of public exposure with emphasis on the most significant sources (i.e. natural background radiation and medical use) and vice versa. The on-going revision of the International Atomic Energy Agency Basic Safety Standards (BSS) provides an opportunity to achieve this internationally so that national regulations can be subsequently remediated. There can be no urgency in a BSS revision that fails to encompass such perspective.  相似文献   

2.
Chile is undergoing a remarkable energy matrix transition to renewable energy. Renewable energies are expanding extraordinarily fast, exceeding earlier predictions. As a result, the country is expected to meet its 2025 goal of generating 20% of its electricity from renewable energy sources quite before. Chile has become one of the first countries in the world with subsidy-free markets, where renewable projects compete directly with other conventional sources. Favorable market conditions and successful policy reforms were keys to fostering this renewable energy development. Although the country has achieved a substantial growth in renewable energy investment in a relatively short period of time, this optimism should be treated with caution. A successful transition requires a combination of a clear decision making, persistent and consistent government policies, and a clear commitment to tackling challenges to accommodate renewable energy in the power system. In this context, this paper analyses the Chilean renewable industry and the required government policies to succeed in this transition. For this purpose, we identify several critical factors that have attracted and that could attract investment to the renewable energy sector and propose key recommendations to effectively address the major challenges faced for the future development of the industry.  相似文献   

3.
Malaysia is rich in renewable energy (RE) resources. Hybrid systems of these resources can contribute strongly to the electrification and sustainable development of rural areas that do not have access to electricity grids. The integration of the generation of hybrid renewable power in remote and rural areas supplies the required power demand and mitigates emissions. Thus, this study reviews the latest literature (theses, journals articles, and conference proceedings) on the need for electricity in remote rural communities, on hybrid RE systems, on environmental impact, and on economic regulation in Malaysia. Power in this country is mainly generated by fossil fuels that emit high concentrations of greenhouse gases. Thus, RE is a potential alternative for to electrify rural areas, to meet current and future energy demands, and to mitigate emissions. Moreover, Malaysia has pledged to reduce its carbon-emission intensity by a maximum of 40 % (2005 level) by the year 2020. Therefore, the implementation of RE technologies in this country is significantly aided by RE projects, research and development activities, technologies, energy policies, and future direction. This review concludes that solar, wind, hydro, and biomass energy, as well as a hybrid of these, can effectively electrify rural areas.  相似文献   

4.
South Africa alone produces move than half of the electricity generated in the entire African continent. In spite of this about, half of South Africans are without electricity in their homes. South Africa's energy production and distribution patterns bear a striking resemblance to its overall economy-a heterogeneous intermingling of First and Third World characteristics. South Africa as a whole is responsible for about 2% of the world's greenhouse gas emissions although it has only 1% of the world's population. The normalisation and democratisation of the country will require enormous efforts to provide electricity, running water and education for the majority of the South Africans previously disadvantaged in the apartheid era. South Africa is trying to comply with the global demand for sustainable development by improving the technologies of its power plants, implementing renewable energy sources, improving efficiency of utilisation of electricity in industry and homes, adopting more efficient standards for electrical appliances, changing of the way of life etc. Although there are some constraints, the country is capable of overcoming these in the years ahead given the political will and proper international assistance  相似文献   

5.
Marine energy     
Marine energy is renewable and carbon free and has the potential to make a significant contribution to energy supplies in the future. In the UK, tidal power barrages and wave energy could make the largest contribution, and tidal stream energy could make a smaller but still a useful contribution. This paper provides an overview of the current status and prospects for electrical generation from marine energy. It concludes that a realistic potential contribution to UK electricity supplies is approximately 80 TWh per year but that many years of development and investment will be required if this potential is to be realized.  相似文献   

6.
Given the constantly raising world-wide energy demand and the accompanying increase in greenhouse gas emissions that pushes the progression of climate change, the possibly most important task in future is to find a carbon-low energy supply that finds the right balance between sustainability and energy security. For renewable energy generation, however, especially the second aspect turns out to be difficult as the supply of renewable sources underlies strong volatility. Further on, investment costs for new technologies are so high that competitiveness with conventional energy forms is hard to achieve. To address this issue, we analyze in this paper a non-autonomous optimal control model considering the optimal composition of a portfolio that consists of fossil and renewable energy and which is used to cover the energy demand of a small country. While fossil energy is assumed to be constantly available, the supply of the renewable resource fluctuates seasonally. We further on include learning effects for the renewable energy technology, which will underline the importance of considering the whole life span of such a technology for long-term energy planning decisions.  相似文献   

7.
A new energy paradigm, consisting of greater reliance on renewable energy sources and increased concern for energy efficiency in the total energy lifecycle, has accelerated research into energy-related technologies. Due to their ubiquity, magnetic materials play an important role in improving the efficiency and performance of devices in electric power generation, conditioning, conversion, transportation, and other energy-use sectors of the economy. This review focuses on the state-of-the-art hard and soft magnets and magnetocaloric materials, with an emphasis on their optimization for energy applications. Specifically, the impact of hard magnets on electric motor and transportation technologies, of soft magnetic materials on electricity generation and conversion technologies, and of magnetocaloric materials for refrigeration technologies, are discussed. The synthesis, characterization, and property evaluation of the materials, with an emphasis on structure-property relationships, are discussed in the context of their respective markets, as well as their potential impact on energy efficiency. Finally, considering future bottlenecks in raw materials, options for the recycling of rare-earth intermetallics for hard magnets will be discussed.  相似文献   

8.
Wind energy     
From its rebirth in the early 1980s, the rate of development of wind energy has been dramatic. Today, other than hydropower, it is the most important of the renewable sources of power. The UK Government and the EU Commission have adopted targets for renewable energy generation of 10 and 12% of consumption, respectively. Much of this, by necessity, must be met by wind energy. The US Department of Energy has set a goal of 6% of electricity supply from wind energy by 2020. For this potential to be fully realized, several aspects, related to public acceptance, and technical issues, related to the expected increase in penetration on the electricity network and the current drive towards larger wind turbines, need to be resolved. Nevertheless, these challenges will be met and wind energy will, very likely, become increasingly important over the next two decades. An overview of the technology is presented.  相似文献   

9.
As a developing country, Malaysia’s prosperity and welfare depends heavily on having access to reliable and secure supplies of energy. As a result, the country’s future energy requirements have become a policy priority in recent years. Energy is essential for human life, and a secure and accessible supply of energy becomes important for the modern societies. Fossil fuels such as coal, oil, and natural gas are currently the world’s primary energy sources and continue to provide energy source to the world. These energy sources have depleted in reserves in recent years and they can also cause irreparably damage to the environment such as global warming and climate change. These environmental concerns can be addressed, to some extent, through more sustainable solutions such as the use of renewable energy resources. In Malaysia, the economic and environmental impacts of fossil fuels use have become hard to ignore. The government has introduced and implemented policy measures to address concerns surrounding the use of fossil fuels and to promote energy efficiency and renewable energy use. In this paper, we review the historical evolution of Malaysian energy policies and initiatives designed to secure diverse energy sources and avoid over-reliance on fossil fuels. In recent years, Malaysia has been catching up with global call to shift to renewable energy use and is now putting a focus on renewable energy in its future energy mix. The paper also discusses challenges and concerns over the future of sustainable energy of the country.  相似文献   

10.
Recent projections of future US carbon dioxide (CO2) emissions are considerably lower than projections made just a decade ago. A myriad of factors have contributed to lower forecasts, including reductions in end-use energy service demands, improvements in energy efficiency, and technological innovations. Policies that have encouraged these changes include renewable portfolio standards, corporate vehicle efficiency standards, smart growth initiatives, revisions to building codes, and air and climate regulations. Understanding the effects of these and other factors can be advantageous as society evaluates opportunities for achieving additional CO2 reductions. Energy system models provide a means to develop such insights. In this analysis, the MARKet ALlocation (MARKAL) model was applied to estimate the relative effects of various energy system changes that have happened since the year 2005 on CO2 projections for the year 2025. The results indicate that transformations in the transportation and buildings sectors have played major roles in lowering projections. Particularly influential changes include improved vehicle efficiencies, reductions in projected travel demand, reductions in miscellaneous commercial electricity loads, and higher efficiency lighting. Electric sector changes have also contributed significantly to the lowered forecasts, driven by demand reductions, renewable portfolio standards, and air quality regulations.  相似文献   

11.
The UNFCCC has stated that energy policies and measures to address climate change should be cost-effective to ensure global benefits at the lowest possible cost. To mitigate the bulk of carbon emission from the electricity sector, a large market penetration of renewable energy technologies with as low cost as possible is a key research topic. The energy-related R&D policy in Japan aims to achieve a green economy. In our study, based on this context, we demonstrated how to optimize the timing of public R&D investment within the framework of a bottom-up partial equilibrium model. The developed optimization model represents the Japanese electricity sector and minimizes the total system cost subject to an accumulated carbon emission constraint. Our main research focus is the role of R&D activity, especially in the innovation stage of renewable technologies. We employ a two-factor learning curve and quantify the impact of the learning effect on the dynamic diffusion of major renewable technologies. The study shows a dynamic technology transition in the Japanese electricity sector and the optimized R&D investment schedule for each renewable technology. With the first-best energy policy, an R&D budget of more than 2000 million USD would be allocated to PV in 2050, which corresponds to 45% of the energy-related Japanese R&D budget in 2050. Because some have criticized the uncertainty problems with dynamic simulations and learning models, supplemental sensitivity analyses are included.  相似文献   

12.
Planning the expansion and energy security of electricity capacity for a national electricity utility is a complex task in almost any economy. Planning is usually an iterative activity and can involve the use of large scale planning optimization systems accompanied by assessment of uncertain scenarios emerging from economic, technological, environmental, and regulatory developments. This paper applies a multiple criteria decision analysis to prioritize investment portfolios in capacity expansion and energy security while principally studying the robustness of the prioritization to multiple uncertain and emergent scenarios. The scenarios are identified through interaction with decision makers and stakeholders. The approach finds which scenarios most affect the prioritization of the portfolios and which portfolios have the greatest upside and downside potential across scenarios. The approach fosters innovation in the use of robust and efficient technologies, renewable energy sources, and cleaner energy fuels. A demonstration is provided for assessing the performance of technology portfolios constructed from investments in nine electricity generation technologies in Mexico.  相似文献   

13.
The palm oil industry potentially can be environmentally sustainable through utilizing the vast availability of biomass residues from palm oil mills as renewable energy sources. This work addresses the optimal operation of a combined bioenergy and solar PV distributed energy generation system to meet the electricity and heat demands of an eco-community comprising a palm oil mill and its surrounding residential community. A multiperiod mixed-integer linear programming planning and scheduling model is formulated on an hourly basis that optimally selects the power generation mix from among available biomass, biogas, and solar energy resources with consideration for energy storage and load shifting. A multiscenario approach is employed that considers scenarios in the form of many possible weather conditions and various energy profiles under varying mill operation modes and residential electricity consumption. The proposed approach is demonstrated on a realistic case study for a palm oil mill in the Iskandar Malaysia economic development region. The computational results indicate that biomass-based resource is the preferred renewable energy to be implemented due to the high cost associated with solar PV. As well, load shifting and energy storage can be feasibly deployed for demand peak shaving particularly for solar PV systems.  相似文献   

14.
Owing to almost unmatched volumetric energy density, Li-ion batteries have dominated the portable electronics industry and solid state electrochemical literature for the past 20 years. Not only will that continue, but they are also now powering plug-in hybrid electric vehicles and electric vehicles. In light of possible concerns over rising lithium costs in the future, Na and Na-ion batteries have re-emerged as candidates for medium and large-scale stationary energy storage, especially as a result of heightened interest in renewable energy sources that provide intermittent power which needs to be load-levelled. The sodium-ion battery field presents many solid state materials design challenges, and rising to that call in the past couple of years, several reports of new sodium-ion technologies and electrode materials have surfaced. These range from high-temperature air electrodes to new layered oxides, polyanion-based materials, carbons and other insertion materials for sodium-ion batteries, many of which hold promise for future sodium-based energy storage applications. In this article, the challenges of current high-temperature sodium technologies including Na-S and Na-NiCl2 and new molten sodium technology, Na-O2 are summarized. Recent advancements in positive and negative electrode materials suitable for Na-ion and hybrid Na/Li-ion cells are reviewed, along with the prospects for future developments.  相似文献   

15.
Recent national focus on the value of increasing US supplies of indigenous renewable energy underscores the need for re-evaluating all alternatives, particularly those that are large and well distributed nationally. A panel was assembled in September 2005 to evaluate the technical and economic feasibility of geothermal becoming a major supplier of primary energy for US base-load generation capacity by 2050. Primary energy produced from both conventional hydrothermal and enhanced (or engineered) geothermal systems (EGS) was considered on a national scale. This paper summarizes the work of the panel which appears in complete form in a 2006 MIT report, 'The future of geothermal energy' parts 1 and 2. In the analysis, a comprehensive national assessment of US geothermal resources, evaluation of drilling and reservoir technologies and economic modelling was carried out. The methodologies employed to estimate geologic heat flow for a range of geothermal resources were utilized to provide detailed quantitative projections of the EGS resource base for the USA. Thirty years of field testing worldwide was evaluated to identify the remaining technology needs with respect to drilling and completing wells, stimulating EGS reservoirs and converting geothermal heat to electricity in surface power and energy recovery systems. Economic modelling was used to develop long-term projections of EGS in the USA for supplying electricity and thermal energy. Sensitivities to capital costs for drilling, stimulation and power plant construction, and financial factors, learning curve estimates, and uncertainties and risks were considered.  相似文献   

16.
This paper presents the current situation and projected planning of the electricity generation sector for Iskandar Malaysia by implementing a model to optimise the cost, utilise the usage of available renewable energy sources, and achieve carbon dioxide reduction targets. This Mixed Integer Linear Programming model was developed with the main objective of minimising the total cost of electricity generation, taking into consideration energy demand, reserve margin, electricity generation, peak and base generation, resource availability, and CO2 emission. Data for the year 2013 were forecasted until 2025 to illustrate the analysis for this study, and are represented via four scenarios. This optimal model is capable of balancing types of fuel and switching coal plants to natural gas power plants. It also enhances the use of renewable energy (RE) to meet CO2 emission targets. The model is further integrated with several other considerations related to energy systems, such as suitability of power plants as peak or base plants, RE resource availability, intermittency of solar power, losses during transmission, fuel selection for biomass, decision to retrofit existing coal power plant to NG power plant, and construction lead time of power plants. The results for this study determined that the optimal scenario is Scenario 3 (CS3). This research proves that Iskandar Malaysia can reduce CO2 emission by 2025 via utilisation of RE. This model is generic and can be applied to any case study, which would be useful for assisting government policy-making.  相似文献   

17.
Replacing traditional energy sources with renewable energy sources is an effective way to achieve emission reduction targets. Focusing on OECD countries from 1990 to 2018, this study examines the determinants of renewable energy innovation by applying a negative binomial model. There are four main findings: (1) Renewable energy patents show an inverted U-shaped curve, peaking in 2010; solar energy accounts for the largest share of patents; and the US is the largest renewable energy innovator, followed by South Korea and Germany. (2) Renewable electricity installed capacity, share of expenditure on research and development (R&D) of GDP, and implementation of the Kyoto Protocol are all found to promote innovation; by comparison, the proportion of renewable energy power generation of the total electricity generating capacity shows a negative effect. The price of crude oil shows no significant effect due to the offset effect between the European and non-European country groups. (3) Share of R&D expenditure of GDP is confirmed to be the force driving technological progress in the solar, geothermal, and marine sectors, and it plays a more important role in Japan than in the US or Europe. Implementation of the Kyoto Protocol has no significant effect on innovation in European countries. (4) Three institutional factors—namely, the legal system and property rights; regulations; and freedom to trade internationally—are confirmed to be the driving forces, whereas this is not the case for the growth and free circulation of money. Policy implications for the optimization of the renewable energy sector's structure, the enhancement of renewable energy capacity, and the improvement of R&D investment and the institutional environment are proposed. Future research should shed light on a broader sample, using micro-level and socio-technical analysis.  相似文献   

18.
Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO(2) each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO(2) emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO(2) emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have still to be assuaged. Other approaches include the application of improved combustion technology, the removal of harmful gases from power-station flues and the use of waste heat to improve overall power-station efficiency. These all have a part to play, but many consider our best hope for emissions reduction to be the use of renewable energy. The main renewable energy contenders are assessed in this paper and realistic estimates of the contribution that each could provide are indicated. It appears that, in the time-scale envisaged by planners for reduction in CO(2) emission, in many countries renewable energy will be unlikely to deliver. At the same time, it is worth commenting that, again in many countries, the level of penetration of renewable energy will fall short of the present somewhat optimistic targets. Of renewable options, wind energy could be used in the short to medium term to cover for thermal plant closures, but for wind energy to be successful, the network will have to be modified to cope with wind's intermittent nature. Globally, hydroelectricity is currently the largest developed source of renewable electricity, but future large-scale projects will probably be limited to the less-developed world: the best schemes in the developed countries have already been exploited. Wave and tidal can be looked on as medium- to long-term generators of electricity, as their respective industries are not as mature as competing renewable resources. Municipal solid-waste combustion and landfill gas technologies can also be seen as short term, as can their rural equivalents, agriculture and forestry waste. Any widespread exploitation of renewable energy will depend on being able to transmit the energy from source to point of use, so the implications for the electrical network from the penetration of substantial levels of renewable energy are presented. Effective management of renewable energy installations will require technical assessment of the range of exploitation strategies, to compare local production of, say, hydrogen and the more traditional transmission of electricity. Such resources will have to compete with others in any national, or grid, system and detailed economic analysis will be necessary to determine the deployment that best fits the trading regime under which the energy will be sold. Consideration will also be necessary to determine how best to control the introduction of this radically new resource such that it does not attract punitive cost overheads until it is mature enough to cope. Finally, it is inescapable that nuclear power is a proven technology that could take its place in any future generation portfolio. Unfortunately, suspicion and mistrust surround waste management and radioactivity release. Unless this is overcome, the lack of confidence engendered by this public mistrust may result in few, if any, new nuclear power stations being built. In the event of that decision, it is difficult to see how CO(2) levels can be significantly reduced: the irony is that nuclear energy may emerge as environmentally essential.  相似文献   

19.
Foundations for offshore wind turbines   总被引:1,自引:0,他引:1  
An important engineering challenge of today, and a vital one for the future, is to develop and harvest alternative sources of energy. This is a firm priority in the UK, with the government setting a target of 10% of electricity from renewable sources by 2010. A component central to this commitment will be to harvest electrical power from the vast energy reserves offshore, through wind turbines or current or wave power generators. The most mature of these technologies is that of wind, as much technology transfer can be gained from onshore experience. Onshore wind farms, although supplying 'green energy', tend to provoke some objections on aesthetic grounds. These objections can be countered by locating the turbines offshore, where it will also be possible to install larger capacity turbines, thus maximizing the potential of each wind farm location. This paper explores some civil-engineering problems encountered for offshore wind turbines. A critical component is the connection of the structure to the ground, and in particular how the load applied to the structure is transferred safely to the surrounding soil. We review previous work on the design of offshore foundations, and then present some simple design calculations for sizing foundations and structures appropriate to the wind-turbine problem. We examine the deficiencies in the current design approaches, and the research currently under way to overcome these deficiencies. Designs must be improved so that these alternative energy sources can compete economically with traditional energy suppliers.  相似文献   

20.
Green energy?     
The UK gets nearly all its energy from the fossil fuels (coal, oil, gas etc.) and nuclear power, approximately 15% being consumed in the form of electricity. It is now well known that the burning of fossil fuels is accompanied by atmospheric pollution in the form of acid rain, ozone depletion and the greenhouse effect. Renewable energy sources, e.g. wind, solar, tidal, wave, hydroelectric and geothermal power do not at present contribute significantly to the UK energy supply and are also accompanied by adverse effects on the environment. The best hope for meeting future energy needs may lie in containing energy consumption, increased generation efficiency and an expanded nuclear power programme. The author discusses the problems of acid rain and the greenhouse effect and describes several forms of renewable energy: wind energy, solar energy, tidal power, wave power, hydroelectricity, biomass geothermal power and nuclear power  相似文献   

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