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1.
While the world energy demand is steadily growing, the concern for the environmental aspects of energy use and natural resource exploitation has increased. A new market has emerged for renewable energy, often referred to as “green energy”. This paper presents an optimization model developed as part of a feasibility study on the idea of exporting renewable energy in the form of hydrogen, from Iceland to the continent of Europe.  相似文献   

2.
The role of hydrogen in long run sustainable energy scenarios for the world and for the case of Germany is analysed, based on key criteria for sustainable energy systems. The possible range of hydrogen within long-term energy scenarios is broad and uncertain depending on assumptions on used primary energy, technology mix, rate of energy efficiency increase and costs degression (“learning effects”). In any case, sustainable energy strategies must give energy efficiency highest priority combined with an accelerated market introduction of renewables (“integrated strategy”). Under these conditions hydrogen will play a major role not before 2030 using natural gas as a bridge to renewable hydrogen. Against the background of an ambitious CO2-reduction goal which is under discussion in Germany the potentials for efficiency increase, the necessary structural change of the power plant system (corresponding to the decision to phase out nuclear energy, the transformation of the transportation sector and the market implementation order of renewable energies (“following efficiency guidelines first for electricity generation purposes, than for heat generation and than for the transportation sector”)) are analysed based on latest sustainable energy scenarios.  相似文献   

3.
4.
Energy and environmental aspects of mobile communication systems   总被引:2,自引:0,他引:2  
The reduction of the energy consumptions of a Telecommunication Power System represents one of the critical factors of the telecommunication technologies, both to allow a sizeable saving of economic resources and to realize “sustainable” development actions. The consumption of about one hundred base stations for mobile phones were monitored for a total of over one thousand days, in order to study the energy consumption in relation to the environmental, electric and logistics parameters of the stations themselves. It was possible to survey, then, the role of the mobile communication systems in the general national energy framework and to plot the best areas of intervention for saving energy and improving the environmental impact, showing the role played by air-conditioning and transmission equipments. Finally, new transmission algorithms and the use of renewable energy based techniques have been tested.  相似文献   

5.
The development of reliable fuel cells power plant based on renewable fuels stands out as one of the promising energy systems solutions for the future. Indeed fuel cells can increase the efficiency and the cleaning of the electrical energy production from renewable fuels. Process simulations of advanced power plants fed by low cost renewable fuels like biomass waste are a key step to develop renewable resources based on high temperature fuel cells applications. The aim of this work is to predict the component behaviour of a specific power plant mainly composed of a small indirectly heated gasifier and a Solid Oxide Fuel Cell (SOFC) and fed by chestnut coppice, waste available in great quantity in Central Italy, as well as in several other European regions. The plant's thermodynamic behaviour is analysed by means of the process simulator CHEMCAD© in which particular models for the SOFC and the gasifier have been developed in FORTRAN by the authors and then interfaced to commercial software. The results of the predictive model are presented and discussed, showing the possibility of an extremely interesting “carbon neutral” small plant configuration with high electrical and global efficiency exclusively based on the use of low cost renewable resources.  相似文献   

6.
The economic viability of producing baseload wind energy was explored using a cost-optimization model to simulate two competing systems: wind energy supplemented by simple- and combined cycle natural gas turbines (“wind+gas”), and wind energy supplemented by compressed air energy storage (“wind+CAES”). Pure combined cycle natural gas turbines (“gas”) were used as a proxy for conventional baseload generation. Long-distance electric transmission was integral to the analysis. Given the future uncertainty in both natural gas price and greenhouse gas (GHG) emissions price, we introduced an effective fuel price, pNGeff, being the sum of the real natural gas price and the GHG price. Under the assumption of pNGeff=$5/GJ (lower heating value), 650 W/m2 wind resource, 750 km transmission line, and a fixed 90% capacity factor, wind+CAES was the most expensive system at ¢6.0/kWh, and did not break even with the next most expensive wind+gas system until pNGeff=$9.0/GJ. However, under real market conditions, the system with the least dispatch cost (short-run marginal cost) is dispatched first, attaining the highest capacity factor and diminishing the capacity factors of competitors, raising their total cost. We estimate that the wind+CAES system, with a greenhouse gas (GHG) emission rate that is one-fourth of that for natural gas combined cycle plants and about one-tenth of that for pulverized coal plants, has the lowest dispatch cost of the alternatives considered (lower even than for coal power plants) above a GHG emissions price of $35/tCequiv., with good prospects for realizing a higher capacity factor and a lower total cost of energy than all the competing technologies over a wide range of effective fuel costs. This ability to compete in economic dispatch greatly boosts the market penetration potential of wind energy and suggests a substantial growth opportunity for natural gas in providing baseload power via wind+CAES, even at high natural gas prices.  相似文献   

7.
Many scenarios have been generated in the last years analysing the international energy market. The variety of these scenarios is manifold, as they are generated by different institutions using different methodological approaches and different framework assumptions. However, these scenarios can roughly be classified into three main groups: “moderate”, “climate protection” and “resource scarcity and high fossil fuel prices”. Analysing the German energy market makes a fourth scenario group necessary, which considers the possible revision of the decided nuclear energy phase out. Most of the existing scenarios developed by different institutions can be allocated into one of these groups. A representative scenario for each group has been selected to illustrate the development of the energy sector until 2030. Contrary to the worldwide primary energy demand (PED), the German PED decreases in each scenario, even though the drop differs strongly throughout the scenarios. On the other hand the structure of the PED in 2030 varies strongly for each scenario, especially regarding the share of fossil energy sources. However, a common robust result can be observed throughout all scenarios, namely the high increase in the share of the renewable energy resources, although the scenario generation processes are not always robust.  相似文献   

8.
The Gulf countries are largely dependent on exporting oil and natural gas for their national budgets. They mainly use domestic fossil fuels for their domestic energy supply. In spite of favorable geographic conditions, especially for solar energy, renewable energies are still a niche application. Abu Dhabi, besides Dubai, the most important emirate in the United Arab Emirates (UAE), has now started a process of “transforming oil wealth into renewable energy leadership,” and has set the long-term goal of a “transition from a 20th Century, carbon-based economy into a 21st Century sustainable economy.” This article is a case study about “Masdar City,” a planned carbon-neutral town in Abu Dhabi. The article describes the key characteristics of Masdar City, analyses the drivers behind the project, identifies the main actors for its implementation, and seeks obstacles to creation and development as well as the policy behind Masdar City. Finally, a first judgment of possible diffusion effects of the project is done.  相似文献   

9.
The study of Very Large Complex systems (“VLCS”), of which modern energy conversion systems are an important subset, requires a holistic approach to analyze the system itself and all of its “external” and “internal” interactions. The view taken in this paper is that the VLCS should be considered as an “extended” (in a sense specified below) thermodynamic system. The evaluation of the flows of matter and energy sustaining a VLCS and the knowledge of the transformations therein can be used to describe the rate of exploitation of the available natural resources, to assess the efficiency of the conversion process, and to provide a quantitative estimate of the impact of the system on the environment. This kind of information is an important part of the essential database of any Decision Support System for both the internal and global policy planning and for resources management. Several assessment methods are in use at present, and each one of them provides a different insight in the “performance” of the conversion chain under examination.  相似文献   

10.
The wider implementation of variable renewable energy sources such as wind across the UK and Ireland will demand interconnection, energy storage and more dynamic energy systems to maintain a stable energy system that makes full use of one of our best renewable energy resources. However large scale energy storage e.g. pumped storage may be economically challenging. Therefore can thermal energy storage deployed domestically fulfil an element of such an energy storage role? Current electricity pricing is based on a ½ hourly timeframe which will be demonstrated to have some benefits for hot water heating from electrical water heaters in the first instance. However heat pumps linked to energy storage can displace fossil fuel heating systems and therefore the question is whether a renewable tariff based on “excess” wind for example is sufficient to operate heat pumps. An initial analysis of this scenario will be presented and its potential role in challenging aspects of fuel poverty.  相似文献   

11.
This communication displays some of our on-going research on the incompleteness of China's advances toward “best practice” in policy-making and institution-building for renewables. In particular, this paper: (1) summarizes how Chinese policies and institutions for the deployment of renewable electricity are only partially compliant with what is internationally recognized as “best practice”; and (2) contextualizes Chinese policies and institutions for renewables in the broader picture of China's political economy. Much as a political economy perspective has aided the understanding of why Chinese economic reforms were partial and unique, the said contextualization might help explain why China's policies and institutions for renewables diverge from “best practice”. Further, given that China proved successful in promoting its economic growth with partial and unique reforms, the partiality and uniqueness of its renewables policies and institutions need not impede the rapid development of renewable electricity. This on-going research has so far combined a review of specialized literature and the business press with semi-structured interviews held with relevant actors in policy, business, and research related to renewable energies.  相似文献   

12.
From the energy point of view, the season we have been living more and more seems the era of sources diversification. The most correct scenario for a sustainable energy future foresees no predominance of one source over the others in any area of the world but a proper energy mix, based on locally available resources and needs.The concept and role of energy vectors is key: “(an energy vector) allows transfer, in space and time, a given quantity of energy, hence making it available for use distantly in time and space from the point of availability of the original source”. Therefore, a scenario that gives full scope for the ES to be immune from the characteristics of non-sustainable resource consumption and waste production, the system itself must shift the focus from resources to vectors (mainly electricity, hydrogen, heat).Smart grids have been largely indicate, in this context, as an answer for their characteristic “needful design” to move from the “old” grids (unidirectional power flows) to “new” bi-directional electricity networks. This is not enough: the real need is for an intelligent management of a complete set of energy sources and vectors, as electricity, heat, hydrogen, bio and non-biofuels, that requires a clear shift that goes beyond smart grids and looks at Intelligent Energy Networks.  相似文献   

13.
The emergence of the “sustainable development” concept as a response to the mining of natural resources for the benefit of multinational corporations has advanced the cause of long-term environmental management. A sustainable development model (SDM) framework that is inclusive of the “whole” natural environment is presented to illustrate the integration of the sustainable development of the “whole” ecosystem. The ecosystem approach is an inclusive framework that covers the natural environment relevant futures and constraints. These are dynamically interconnected and constitute the determinates of resources development component of the SDM. The second component of the SDM framework is the resources development patterns, i.e., the use of land, water, and atmospheric resources. All of these patterns include practices that utilize environmental resources to achieve a predefined outcome producing waste and by-products that require disposal into the environment. The water quality management practices represent the third component of the framework. These practices are governed by standards, limitations and available disposal means subject to quantity and quality permits. These interconnected standards, practices and permits shape the resulting environmental quality of the ecosystem under consideration. A fourth component, environmental indicators, of the SDM framework provides a measure of the ecosystem productivity and status that may differ based on societal values and culture. The four components of the SDM are interwoven into an outcome assessment process to form the management and feedback models. The concept of Sustainable Development is expressed in the management model as an objective function subject to desired constraints imposing the required bounds for achieving ecosystem sustainability. The development of the objective function and constrains requires monetary values for ecosystem functions, resources development activities and environmental cost. The feedback model ensures policy and resources use changes required for sustainability. An iterative process would be required to define the optimum ecosystem development plan that satisfies sustainable outcome.  相似文献   

14.
Energy sustainability is becoming an increasing issue—or rather “the” issue in our society. Often it is reduced to a purely technical problem. Renewable energies and energy-efficient technologies are developed to solve the problem, but finally the end-users will “decide” how much and what kind of energy they are going to consume. This article is targeted on showing the environmental psychological aspects of the change of energy demand and supply. It builds upon a transactional model of human technology interchange and summarises environmental psychological work done during more than 5 years. It refers to the idea of energy sustainable communities (ESCs), shows the development of one example community and concentrates on one aspect of the social dimension of ESCs, the “acceptance of renewable energy technology”, its definition and measurement in Germany.  相似文献   

15.
Access to energy is known as a key issue for poverty reduction. Electrification rate of sub-Saharan countries is one of the lowest among the developing countries. However, this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original “flexy-energy” concept of hybrid solar PV/diesel/biofuel power plant, without battery storage, is performed in this paper. This concept is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. For landlocked countries like Burkina Faso, this concept could help them reducing their electricity bill (then their fuel consumption) and accelerate their rural and peri-urban electrification coverage.  相似文献   

16.
The purpose of this paper is to analyze the socio-economic dynamics that are brought about by renewable energy technologies. We call this dynamic “Social Innovation” as it changes the rules of risk–benefit distribution and the roles of social actors. For this purpose, we take up a typical case in Japan, community wind power in which the initial cost is funded by the investment of citizens. Through this case study, we examine how the citizens’ initiative can affect the social acceptance of renewable energy as well as social change. Based on interviews with those involved in these projects, we analyze the interests of the various actors involved in community wind power projects in a framework of “actor network theory”, which enables us to understand the detail of each actor's position. This study also involved a quantitative survey of investors. The case study clarified that there was a remarkable difference in the interests of the main actors in the community wind power projects, the networks are complex and actors share various interests such as economic interests and a sense of social commitment, participation and contribution. These incentives are also clarified in quantitative data. However, the variety of incentives differs in each project.  相似文献   

17.
The study of hydrogen as an alternative fuel, clean and “environment friendly”, has been in the last years and continues to be object of many studies, international projects and standard development. Hydrogen is a fundamental energy carrier, to be developed together with other renewable resources, for the transition to a sustainable energy system.  相似文献   

18.
This paper addresses the impact of environmentally based market failure constraints on the adoption of renewable energy technologies through the quantification in financial terms of the externalities of electric power generation, for a range of alternative commercial and almost-commercial technologies. It is shown that estimates of damage costs resulting from combustion of fossil fuels, if internalised into the price of the resulting output of electricity, could lead to a number of renewable technologies being financially competitive with generation from coal plants. However, combined cycle natural gas technology would have a significant financial advantage over both coal and renewables under current technology options and market conditions. On the basis of cost projections made under the assumption of mature technologies and the existence of economies of scale, renewable technologies would possess a significant social cost advantage if the externalities of power production were to be “internalised”. Incorporating environmental externalities explicitly into the electricity tariff today would serve to hasten this transition process.  相似文献   

19.
Morocco, Algeria and Tunisia, the three countries of the North African Maghreb region, are showing increased efforts to integrate renewable electricity into their power markets. Like many other countries, they have pronounced renewable energy targets, defining future shares of “green” electricity in their national generation mixes. The individual national targets are relatively varied, reflecting the different availability of renewable resources in each country, but also the different political ambitions for renewable electricity in the Maghreb states. Open questions remain regarding the targets’ economic impact on the power markets. Our article addresses this issue by applying a linear electricity market optimization model to the North African countries. Assuming a competitive, regional electricity market in the Maghreb, the model minimizes dispatch and investment costs and simulates the impact of the renewable energy targets on the conventional generation system until 2025. Special emphasis is put on investment decisions and overall system costs.  相似文献   

20.
The extraction of energy resources and the preservation of sensitive in-situ environmental assets are invariably mutually exclusive alternatives. The opportunity cost value of preserving the environmental assets can be assessed by recourse to resource rent taxes, and threshold values. The case study analysis carried out in this paper suggests that the preservation of these assets could be justifiable on the grounds of “acceptable sacrifice”.  相似文献   

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