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1.
Proton Exchange Membrane Fuel Cells (PEMFC) have proven to be a promising energy conversion technology in various power applications and since it was developed, it has been a potential alternative over fossil fuel-based engines and power plants, all of which produce harmful by-products. The inlet air coolant and reactants have an important effect on the performance degradation of the PEMFC and certain power outputs. In this work, a theoretical model of a PEM fuel cell with solar air heating system for the preheating hydrogen of PEM fuel cell to mitigate the performance degradation when the fuel cell operates in cold environment, is proposed and evaluated by using energy analysis. Considering these heating and energy losses of heat generation by hydrogen fuel cells, the idea of using transpired solar collectors (TSC) for air preheating to increase the inlet air temperature of the low-temperature fuel cell could be a potential development. The aim of the current article is applying solar air preheating for the hydrogen fuel cells system by applying TSC and analyzing system performance. Results aim to attention fellow scholars as well as industrial engineers in the deployment of solar air heating together with hydrogen fuel cell systems that could be useful for coping with fossil fuel-based power supply systems.  相似文献   

2.
Hydrogen is often suggested as a universal fuel that can replace fossil fuels. This paper analyses the feasibility of direct hydrogen utilisation in all energy sectors in a 100% renewable energy system for Europe in 2050 using hour-by-hour energy system analysis. Our results show that using hydrogen for heating purposes has high costs and low energy efficiency. Hydrogen for electricity production is beneficial only in limited quantities to restrict biomass consumption, but increases the system costs due to losses. The transport sector results show that hydrogen is an expensive alternative to liquid e-fuels and electrified transport due to high infrastructure costs and respectively low energy efficiency. The industry sector may benefit from hydrogen to reduce biomass at a lower cost than in the other energy sectors, but electrification and e-methane may be more feasible. Seen from a systems perspective, hydrogen will play a key role in future renewable energy systems, but primarily as e-fuel feedstock rather than direct end-fuel in the hard-to-abate sectors.  相似文献   

3.
Global warming and tightening environmental legislation is putting pressure on divesting from fossil fuel in the energy sector, with the transport sector likely to see the biggest changes. Current alternative energy sources are electric vehicles and hydrogen. Conventional hydrogen production technologies are fossil fuel based, emitting significant amounts of CO2 into the atmosphere. This paper explores various ways to integrate solar thermal technologies into hydrogen production to generate carbon free hydrogen in South Africa. South Africa's abundant solar resource indicates that the country may become a significant player in the hydrogen market. However, the high capital cost associated with solar thermal energy put solar thermal hydrogen at a price disadvantage against conventional production technologies. Significant market penetration for solar thermal hydrogen is not expected within the next decade, but cost reduction due to improved manufacturing techniques and larger manufacturing volumes might close the gap in the long term.  相似文献   

4.
Hydrogen fuelling station is an infrastructure for the commercialisation of hydrogen energy utilising fuel cells, particularly, in the automotive sector. Hydrogen fuel produced by renewable sources such as the solar and wind energy can be an alternative fuel to depress the use of fuels based on fossil sources in the transport sector for sustainable clean energy strategy in future. By replacing the primary fuel with hydrogen fuel produced using renewable sources in road transport sector, environmental benefits can be achieved. In the present study, techno-economic analysis of hydrogen refuelling station powered by wind-photovoltaics (PV) hybrid power system to be installed in ?zmir-Çe?me, Turkey is performed. This analysis is carried out to a design of hydrogen refuelling station which is refuelling 25 fuel cell electric vehicles on a daily basis using hybrid optimisation model for electric renewable (HOMER) software. In this study, National Aeronautics and Space Administration (NASA) surface meteorology and solar energy database were used. Therefore, the average wind speed during the year was assessed to be 5.72 m/s and the annual average solar irradiation was used to be 5.08 kW h/m2/day for the considered site. According to optimisation results obtained for the proposed configuration, the levelised cost of hydrogen production was found to be US $7.526–7.866/kg in different system configurations. These results show that hydrogen refuelling station powered by renewable energy is economically appropriate for the considered site. It is expected that this study is the pre-feasibility study and obtained results encougare the hydrogen refuelling station to be established in Turkey by inventors or public institutions.  相似文献   

5.
Demand for fossil fuels is increasing day by day with the increase in industrialization and energy demand in the world. For this reason, many countries are looking for alternative energy sources against this increasing energy demand. Hydrogen is an alternative fuel with high efficiency and superior properties. The development of hydrogen-powered vehicles in the transport sector is expected to reduce fuel consumption and air pollution from exhaust emissions. In this study, the use of hydrogen as a fuel in vehicles and the current experimental studies in the literature are examined and the results of using hydrogen as an additional fuel are investigated. The effects of hydrogen usage on engine performance and exhaust emissions as an additional fuel to internal combustion gasoline, diesel and LPG engines are explained. Depending on the amount of hydrogen added to the fuel system, the engine power and torque are increased at most on petrol engines, while they are decreased on LPG and diesel engines. In terms of chemical products, the emissions of harmful exhaust gases in gasoline and LPG engines are reduced, while some diesel engines increase nitrogen oxide levels. In addition, it is understood that there will be a positive effect on the environment, due to hydrogen usage in all engine types.  相似文献   

6.
Both fuel cell and electric vehicles have the potential to play a major role in a transformation towards a low carbon transport system that meets travel demands in a cleaner and more efficient way if hydrogen and electricity was produced in a sustainable manner. Cost reductions are central to this challenge, since these technologies are currently too expensive to compete with conventional vehicles based on fossil fuels. One important mechanism through which technology costs fall is learning-by-doing, the process by which cumulative global deployment leads to cost reduction. This paper develops long-term scenarios by implementing global technology learning endogenously in the TIAM-UCL global energy system model to analyse the role of hydrogen and electricity to decarbonise the transport sector. The analysis uses a multi-cluster global technology learning approach where key components (fuel cell, electric battery and electric drive train), to which learning is applied, are shared across different vehicle technologies such as hybrid, plug-in hybrid, fuel cell and battery operated vehicles in cars, light goods vehicles and buses. The analysis shows that hydrogen and electricity can play a critical role to decarbonise the transport sector. They emerge as complementary transport fuels, rather than as strict competitors, in the short and medium term, with both deployed as fuels in all scenarios. However, in the very long-term when the transport sector has been almost completely decarbonised, technology competition between hydrogen and electricity does arise, in the sense that scenarios using more hydrogen in the transport sector use less electricity and vice versa.  相似文献   

7.
Nowadays, the use of renewable energy sources is one of the keys to achieve the sustainable development of societies. The intensive use of fossil fuels has caused effects in the environment and the human health. Greenhouse gas emissions and the carcinogenic effect of diesel are widely demonstrated. The production of clean energy based on renewable sources and the use of hydrogen as an energy vector in general and as an alternative fuel in particular represent a technically feasible reality. However, it is necessary to study the economic variables of centralized or distributed production of hydrogen as an alternative fuel. The aim of this paper is to analyze the technical and economic viability of a centralized generation hydrogen plant for mobility use. It was performed a sensitivity analysis of main parameters such as size of hydrogen production plant, operating hours of the plant, investment costs of the main equipment and electricity price. A NPV of 1,272,692 and a 9-year pay-back were obtained for a centralized hydrogen production plant of 2 MW, considering commercial values of the main evaluation parameters. The sensitivity analysis determines that the main variables affecting the NPV are the price of electricity and the operating hours of the plant. With 95% of confidence, the NPV will be positive with an 80.19% of certainty. Therefore, centralized hydrogen production represents a technically viable, environmentally friendly and economically attractive process that can rapidly position hydrogen as an alternative fuel for mobility.  相似文献   

8.
Interest in the role embodied energy plays in international trade and its subsequent impact on energy security has grown. As a developed nation, the UK's economic structure has changed from that of a primary producer to that of a primary consumer. Although the UK's energy consumption appears to have peaked, it imports a lot of energy embodied in international trade alongside the more obvious direct energy imports. The UK has seen increasing dependency on imported fossil energy since the UK became a net energy importer in 2005. In this paper an energy input–output model is established to calculate not only the amount of fossil energy embodied in UK's imports and exports, but also the sector and country distributions of those embodied fossil energy. The research results suggest the following: UK's embodied fossil energy imports have exceeded embodied fossil energy exports every year since 1997, UK embodied energy imports through the so-called ‘Made in China’ phenomena are the largest accounting for 43% of total net fossil energy imports. If net embodied fossil energy imports are considered, the gap between energy consumption and production in UK is much larger than commonly perceived, with subsequent implications to the UK's energy security.  相似文献   

9.
This study analyzes the impact of the introduction of hydrogen as fuel in the road transportation sector of Korea. Since this sector is completely dependent on petroleum and alternative technologies such as fuel cell vehicles, hydrogen is one alternative fuel that could meet the challenges that Korea is facing due to rising oil prices. This study uses a scenarios-based energy economic model including the hydrogen path way as a sub-energy system to explore the energy system of Korea through 2044. This study also constructs six scenarios consisting of three government policies concerning carbon dioxide reduction and two oil price scenarios in order to assess the impact on hydrogen as fuel in the road transportation sector. The results of this study show that in a particular case (high Btu tax and oil prices) the share of hydrogen would reach 76% of the road transportation sector, and hydrogen would be produced mainly from renewable and nuclear resources via electrolysis facilities. It is also revealed that hydrogen is effective at reducing carbon dioxide, improving energy efficiency and contributing to the energy security of Korea.  相似文献   

10.
Sustainable energy is becoming of increasing concern world-wide. The rapid growth of global climate changes along with the fear of energy supply shortage is creating a large consensus about the potential benefits of a hydrogen economy coming from renewable energy sources. The interesting perspectives are over-shadowed by uncertainties about the development of key technologies, such as renewable energy sources, advanced production processes, fuel cells, metal hydrides, nanostructures, standards and codes, and so on. The availability of critical technologies can create a base for the start of the hydrogen economy, as a fuel and energy carrier alternative to the current fossil resources. This paper will explore the rationale for such a revolution in the energy sector, will describe the state-of-the-art of major related technologies (fuel cell, storage systems, fuel cell vehicles) and current niche applications, and will sketch scientific and technological challenges and recommendations for research and development (R&D) initiatives to accelerate the pace for the widespread introduction of a hydrogen economy.  相似文献   

11.
Nobody can doubt today that hydrogen will, in the not-too-distant future, represent a very significant percentage of the total energy used by the transport sector. This study therefore consists of the modelling and simulation of energy consumption, by type of vehicle and fuel or energetic vector, in the road transport sector of the Madrid Region, during the period 2010–2050, using the MARKAL model. It has been necessary to complete this model by adding numerous specifications in order to determine the features of the Madrid Region, the richest Region in Spain. For the purpose of the study, three growth scenarios, based on short-term energy forecasts made by different official organizations, have been proposed for the energy consumption of the road transport sector in the Region. The results show a profound change in the current situation as there is a significant decrease in the consumption of fossil fuels and an increase in that of alternative non-fossil fuels and hydrogen. The latter, in particular, will rise from 0.1% in the year 2010, to around 50% in the year 2050, which will mean a drastic drop in the sector's CO2 and atmospheric pollutant emissions.  相似文献   

12.
Green hydrogen reduces carbon dioxide emission, advances the dependency on fossil fuels and improves the economy of the energy sector, especially in developing countries. Hydrogen is required for the green transportation sector and many other industrial applications. However, the high cost of green hydrogen production reduces the fast development of renewable energy projects based on hydrogen production. So, sizing by optimization is required to determine the optimum solutions for green hydrogen production. In this context, this paper aims to analyze three methods that can be developed and implemented for the production of green hydrogen for refueling stations using photovoltaic (PV) systems. Techno-economic models are adopted to calculate the Levelized Hydrogen Cost (LHC) for the PV grid-connected system, stand-alone PV system with batteries, and stand-alone PV system with fuel cells. The photovoltaic systems based green hydrogen refueling stations are optimized using Homer software. The optimization results of the Net Profit Cost (NPC), and the LHC permit the comparison of the three cases and the selection of the optimal solution. The analysis has shown that a 3 MWp grid-connected PV system represents a promising green hydrogen production at an LHC of 5.5 €/kg. The system produces 58 615 kg of green hydrogen per year reducing carbon dioxide emission by 8209 kg per year. The LHC in the stand-alone PV system with batteries, and stand-alone PV system with fuel cells are 5.74 €/kg and 7.38 €/kg, respectively.  相似文献   

13.
Electricity generation in different countries is based on a variety of fuel mixes compromising solid fossil fuels, oil, natural gas, nuclear and renewable energy sources. While in the past, national energy agendas have directed the optimal utilisation of domestic resources as a means to achieve supply security, today's environmental debates are influencing the electricity fuel mix in new directions. In this paper we examine the electricity sectors of Germany, Greece, Poland and the UK in an attempt to identify the policy and technology choices implemented in each country. The country selection is deliberately made to facilitate an extended overview of national agendas, varying domestic energy resources and industrialisation levels but still within the common EU framework. The focus is placed on policies related to two objectives, climate change mitigation and improving electricity supply security. The theoretical framework developed provides the possibility to assess the electricity sector independence at a national level using a multi-parametric analysis of the fuel mix data. Through a comparative assessment of the knowledge gained in different countries the authors provide insights and suggestions that allow for an improved understanding of the trade-offs and synergies that various policy options may introduce.  相似文献   

14.
The Directive 2009/28/EC established the overall target that 20% of energy consumption should be represented by renewable energy sources by 2020 in each European member state. Furthermore, the Directive sets a mandatory 10% minimum target for biofuels in the transport sector.Biofuels are potentially an important alternative to mineral diesel. We propose a pilot production line of biodiesel from sunflower on local scale in the Province of Siena (Tuscany) to research a possible reduction of fossil fuel consumption in the transport sector.This study might represent an opportunity to reduce petroleum dependence in the transport sector.Environmental Impact Indicators were provided by Material Flow Accounting, Embodied Energy Analysis and Emergy Accounting. Results showed that agricultural phase is the critical step in the production line.A comparative Life Cycle Assessment analysis for the biodiesel production line with mineral diesel production showed environmental advantages of the biofuel production, however requiring a higher land demand. Therefore, biodiesel may not the optimal solution on large scale but might be a good alternative to fossil fuel. This would depend upon the entire production cycle taking place in a limited area. This is necessary in order to fulfill the needs of local farms and small enterprises.  相似文献   

15.
Understanding the scale and nature of hydrogen's potential role in the development of low carbon energy systems requires an examination of the operation of the whole energy system, including heat, power, industrial and transport sectors, on an hour-by-hour basis. The Future Energy Scenario Assessment (FESA) software model used for this study is unique in providing a holistic, high resolution, functional analysis, which incorporates variations in supply resulting from weather-dependent renewable energy generators. The outputs of this model, arising from any given user-definable scenario, are year round supply and demand profiles that can be used to assess the market size and operational regime of energy technologies. FESA was used in this case to assess what - if anything - might be the role for hydrogen in a low carbon economy future for the UK.In this study, three UK energy supply pathways were considered, all of which reduce greenhouse gas emissions by 80% by 2050, and substantially reduce reliance on oil and gas while maintaining a stable electricity grid and meeting the energy needs of a modern economy. All use more nuclear power and renewable energy of all kinds than today's system. The first of these scenarios relies on substantial amounts of ‘clean coal’ in combination with intermittent renewable energy sources by year the 2050. The second uses twice as much intermittent renewable energy as the first and virtually no coal. The third uses 2.5 times as much nuclear power as the first and virtually no coal.All scenarios clearly indicate that the use of hydrogen in the transport sector is important in reducing distributed carbon emissions that cannot easily be mitigated by Carbon Capture and Storage (CCS). In the first scenario, this hydrogen derives mainly from steam reformation of fossil fuels (principally coal), whereas in the second and third scenarios, hydrogen is made mainly by electrolysis using variable surpluses of low-carbon electricity. Hydrogen thereby fulfils a double facetted role of Demand Side Management (DSM) for the electricity grid and the provision of a ‘clean’ fuel, predominantly for the transport sector. When each of the scenarios was examined without the use of hydrogen as a transport fuel, substantially larger amounts of primary energy were required in the form of imported coal.The FESA model also indicates that the challenge of grid balancing is not a valid reason for limiting the amount of intermittent renewable energy generated. Engineering limitations, economic viability, local environmental considerations and conflicting uses of land and sea may limit the amount of renewable energy available, but there is no practical limit to the conversion of this energy into whatever is required, be it electricity, heat, motive power or chemical feedstocks.  相似文献   

16.
Presently majority of the world’s energy demand is met by fossil fuels. These fuels are depleting at an alarming rate. Thus in future, our energy systems will need to be renewable and sustainable, efficient and cost-effective, convenient and safe. Among the various alternative fuels, hydrogen is a long-term renewable and least polluting fuel (produced from renewable energy sources). Its clean burning characteristics help to meet the stringent emission norms. Majority of the work using hydrogen as a fuel is being done in spark ignition engine, however, in this experimental investigation efforts have been made to utilize it in compression ignition engine.  相似文献   

17.
Over the period between 1990–1 and 2012–3, fossil fuel use on farms has risen and its indirect use in farming, particularly for non-energy purposes, is also growing. Consequently, both energy intensity and fossil fuel intensity are rising for Indian agriculture. But, these are declining for the aggregate Indian economy. Thus, revision of fossil fuel prices acquires greater significance for Indian agriculture than for rest of the economy. There are significant differences across crops. The crop-level analysis is supplemented by an alternative approach that utilizes a three-sector input–output (I–O) model for the Indian economy representing farming, fossil fuels, and rest of economy. Fossil fuels sector is assessed to portray, in general, strong forward linkages. The increase in total cost of farming, for a given change in fossil fuel prices, is estimated as a multiple of increase in direct input cost of fossil fuels in farming. From the three-sector aggregated economy this multiple was estimated at 3.99 for 1998–9. But it grew to 6.7 in 2007–8. The findings have stronger ramifications than commonly recognized, for inflation and cost of implementing the policy on food security.  相似文献   

18.
The maritime transportation sector globally depends on fossil resources while this option is both diminishing and causing serious environmental and air pollution issues. Recently, hydrogen energy becomes one of the key alternatives addressing these concerns under the increasing press effect of the international community.The use of hydrogen as an energy source in ships is provided by fuel cell technologies. Although there are many types of fuel cells, Proton Exchange Membrane Fuel Cell (PEMFC) is the most widely used fuel cell type in the maritime industry. The most important handicap for the use of hydrogen in ships seems to be the production and storage of it. For this reason, fuel cell technology and hydrogen production and storage systems must be developed in order to use hydrogen as the main propulsion system in long-distance transportation in the maritime sector.In this study, Reference Energy System (RES) is established for a chemical tanker ship to determine the current energy flow from various resources to demands. Then the appropriate parameters are assigned and this framework is specified by the respective data. Following this phase; the current situation has been developed as the base scenario and analyzed by using the Low Emission Analysis Programme (LEAP) energy modeling platform. Additionally, two alternative scenarios including the hydrogen-based have been applied against the base scenario to compare the environmental results in the 2017–2050 time period. When the results are evaluated, it is predicted that although it is not sufficient for IMO and EMSA targets, implementation of hydrogen contributes to the carbon emission reduction positively and it will be more beneficial to apply to the main drive system with the technological developments to be made in the near future.  相似文献   

19.
In recent years, growing attention has been given to new alternative energy sources and exergy analysis since fossil fuels cause emissions that have some negative impacts on earth such as global warming, greenhouse effect etc. New power generation systems have been developed in order to reduce or eliminate these impacts as possible. So that, new alternative energy systems have been taken place instead of fossil fuel based systems with nearly zero emission levels. One of them is solid polymer electrolyte or proton exchange membrane (PEM) fuel cell. Although it has significant advantages, there are some disadvantages such as cost, and hydrogen is not a fuel that can be easily obtained. For these reasons, efficiency of a PEM fuel cell has a great significance. Energy efficiency of a system is the most important parameter for utilization. But, energy analysis does not always show the capacity to do work potential of energy of a system. Exergy analysis must be investigated for a system in order to see available work of the system. Because of disadvantages of the PEM fuel cell, exergy analysis has quite importance. In this paper PEM fuel cell and exergy analysis of PEM fuel cell are combined and investigated. A detailed review of the past and recent research activities has been documented. The review focuses on exergy analysis of both PEM fuel cells and PEM based combined heat and power (CHP) systems at different operating parameters. It is concluded that there are a lot of parameters which effects the exergy efficiencies of systems.  相似文献   

20.
A controlling influence on hydrogen as an energy vector will be the competitive position of electricity. Development of the distribution infrastructure for hydrogen can be expected to complement the electric system, the two together providing an optimum energy network. Hydrogen will be an accommodating fuel: fossil hydrogen helping, in some markets, to extend the use of fossil fuels as primary energy sources; nonfossil hydrogen later providing an alternative to electricity as an energy carrier for some developing nonfossil resources.  相似文献   

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