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1.
The objective of this study was to calculate indicative ranges of production costs and assess the main sources of cost for a number of energy crops, both annual and perennial, on a regional level in Europe. The production costs were calculated in terms of the economic compensation required by the farmer in order to grow the crop, and therefore include not only the cost of cultivation, but also the costs of land and risk, which are often omitted in production cost calculations. The cost of land was calculated as the opportunity cost based on the production of cereals. Thus, higher food prices lead to higher land costs, which in turn lead to higher energy crop production costs. The analysis was performed for three cases with different assumptions concerning yields and production cost reductions resulting from scale (total cultivation area in the region), and learning effects. The calculated energy crop production costs were found to be consistently lowest for short-rotation coppice (SRC) crops and highest for annual straw crops. The production costs of SRC crops were calculated to be about 4–5 € GJ−1 under present conditions and 3–4 € GJ−1 under improved future conditions. The production costs for perennial grasses were calculated to be about 6–7 € GJ−1 and 5–6 € GJ−1 under present and improved future conditions, respectively. The production costs for annual straw crops were estimated to be 6–8 € GJ−1 under present conditions with small potential for cost reductions in the future.  相似文献   

2.
Hydrogen (H2) generation using Steam Methane Reforming (SMR) is at present the most economical and preferred pathway for commercial H2 generation. This process, however, emits a considerable amount of CO2, ultimately negating the benefit of using H2 as a clean industrial feedstock and energy carrier. That has prompted growing interest in enabling CO2 capture from SMR for either storage or utilisation and producing zero-emission “blue H2”. In this paper, we propose a spatial techno-economic framework for assessing blue hydrogen production SMR hubs with carbon capture, utilisation and storage (CCUS), using Australia as a case study. Australia offers a unique opportunity for developing such ‘blue H2’ hubs given its extensive natural gas resources, availability of known carbon storage reservoirs and an ambitious government target to produce clean/zero-emission H2 at the cost of <A$2 kg?1 by 2030. Our results highlight that the H2 production costs are unsurprisingly dominated by natural gas, with the additional capital requirement of carbon capture and storage (CCS) also playing a critical role. These outcomes are especially pertinent for eastern Australian states, as they are experiencing high natural gas costs and would generally require extensive CO2 transport and storage infrastructure to tap potential storage reservoirs, ultimately resulting in a higher cost of producing H2 (>A$2.7 kgH2?1). On the other hand, Western Australia offers lower gas pricing and relatively lesser storage costs, which would lead to more economically favourable hydrogen production (<A$2.2 kgH2?1). We further explore the possibility of utilising the emissions captured at blue SMR hubs by converting them into formic acid through CO2 electroreduction, yielding revenue that will decrease the cost of blue H2 and reduce the reliance on CO2 storage. Our analysis reveals that formic acid production utilising a 10 MW CO2 electrolyser can potentially reduce H2 production costs by between 4 and 9%. Further cost reduction is possible by scaling the CO2 electrolyser capacity to convert a larger portion of the emissions captured, albeit at the cost of higher capital investment, electricity consumption and saturating the market for formic acid. Thus, carbon utilisation for a range of products with high market demand represents a more promising approach to replacing the need for costly carbon storage. Overall, our modelling framework can be adapted for global application, particularly for regions interested in generating blue H2 and extended to include other CO2 utilisation opportunities and evaluate other hydrogen production technologies.  相似文献   

3.
In the context of controlling greenhouse gas emissions, the directive on a Europe-wide trading scheme may be perceived as one of the most important milestones in recent years. Prior to its start, however, a number of very specific design features have to be agreed upon. Regarding the allocation of allowances, a distribution (almost) free of charge seems to be the most likely choice. An aspect that has interestingly attracted little attention in the past is the question of how to allocate emission rights over time. The following paper analyses different allocation options in multi-period emissions trading that are currently discussed in the European context. The options are applied for the electricity sector which is simulated over two periods. The paper distinguishes between a market effect of emissions trading and compliance costs for meeting the emission reduction obligation. The market effect results from a price increase which is due to the fact that opportunity costs for using allowances must be considered. It turns out that the electricity sector as a whole gains from the introduction of the instrument due to the increase of the electricity price. With regard to the different allocation options, it is found that utilities have different preferences depending on the fuel used.  相似文献   

4.
Mobile distributed pyrolysis facilities have been proposed for delivery of a forest residue resource to bio-fuel facilities. This study examines the costs of producing hydrogen or synthetic petrol (gasoline) and diesel from feedstock produced by mobile facilities (bio-oil, bio-slurry, torrefied wood). Results show that using these feedstock can provide fuels at costs competitive to conventional bio-fuel production methods using gasification of a woodchip feedstock. Using a bio-oil feedstock in combination with bio-oil steam reforming or bio-oil upgrading can produce hydrogen or petrol and diesel at costs of 3.25 $ kg−1 or 0.86 $ litre−1, respectively, for optimally sized bio-fuel facilities. When compared on an energy basis ($ GJ−1), hydrogen production costs tend to be lower than those for synthetic petrol or diesel production across a variety of bio-fuel production pathways.  相似文献   

5.
The consumption of wood pellets grew rapidly during the last decade. In this paper we compare the development of the production factors for wood pellet markets in Finland, Germany, Sweden, Norway and the US; we analyze how domestic market prices for pellet production factors as well as domestic market prices for pellets vary among the countries. The analyses are based on two model plants. The first represents common technologies for small scale pellet production based on dry residues from sawnwood production, while the second represents large scale production based on a blend of dry and wet materials. The results show how differences in costs of feedstock, energy and labor affect the profitability of pellet production and hence the development of pellet production in the analyzed countries. Pellet producers in the US have lower feedstock costs than producers in the analyzed European countries. The economic sustainability for European pellet producers depends to a large extent on their domestic markets as internationally traded pellets are priced lower than their production costs. Future pellet production will, to a greater extent, be based on wet feedstock such as roundwood and wet sawdust. These feedstocks are also demanded by wood-based industries (pulp and paper, particle- and fiber-board) as well as for traditional fuelwood. The transition from smaller pellet plants using dry feedstock to larger plants using wet feedstock in future pellet production, can be expected to follow comparative advantages regarding feedstock and energy costs, but also with respect to economies of scale.  相似文献   

6.
This paper presents the market clearing of joint energy and reserves auctions and its mathematical formulation, focusing on a possible implementation of the Payment Cost Minimization (PCM). It also discusses another key point in debate: whether market clearing algorithm should minimize offer costs or payment costs? An aggregated simultaneous market clearing approach is proposed for provision of ancillary services as well as energy, which is in the form of Mixed Integer Nonlinear Programming (MINLP) formulation. In the MINLP formulation of the market clearing process, the objective function (Payment cost or offer cost) are optimized while meeting AC power flow constraints, system reserve requirements and lost opportunity cost (LOC) considerations. The model is applied to the IEEE 24-bus Reliability Test System (IEEE 24-bus RTS), and simulation studies are carried out to examine the effectiveness of each objective function.  相似文献   

7.
In this study, we evaluated six hydrogen-producing methods using a fuzzy analytic hierarchy process (AHP) under benefits, opportunities, costs, and risks concepts. Twelve factors were set up, and the weights of each factor were appraised using the fuzzy AHP method. We conclude that steam methane reforming is the optimal method for hydrogen production in Korea; equipment investment cost and market size are the most important factors, while the indirect benefits such as spillover effect, human resource development, and environmental contribution are less important. The results show that achieving economic feasibility and lowering risks are very important. Therefore, considering stable natural gas prices and unconventional gas production, steam methane reforming is a promising option for hydrogen production.  相似文献   

8.
Industrial production of sodium sulfate using solar ponds   总被引:1,自引:0,他引:1  
An example of the use of a solar pond in the mining industry, the production of industrial grade sodium sulfate from a mineral consisting in a mixture of sulfate decahydrate, sodium chloride and clays, is described. The industrial solar process uses the solar pond as a basin where the mineral is dissolved at temperatures around 40°C. The sodium sulfate is separated from the concentrated hot solution by fractional crystallization during the night, at low temperature. This design was tested successfully in a prototype with a 400 m2 pond. An industrial plant using this process has been working in a batch mode for several years. The plant is described and its operation and costs are analyzed. They compare favorably with the results obtained with a conventional plant because of lower initial investments and operational costs.  相似文献   

9.
Agro residues constitute the biggest source of biomass in Greece. Although large amounts of agricultural residues are produced in Greece each year, their contribution towards meeting national energy demand has remained rather low due to inefficient and unplanned use. These residues have low heating value per unit volume and high transportation and storage costs when used in as received condition; these difficulties can be largely overcome through densification which is an effective approach for using residues efficiently. Densification offers an opportunity to make biomass easier to handle and transport. The cost of the endeavor is a challenge. However, there is a need to consider a system that operates year around with several biomass materials. The investigation in the Greek and the international market shows that mixed biomass pellets are promising fuels and with the appropriate support these fuels have many prospects for the future. The use of biomass pellets would not only create new market opportunities for agricultural industries, it would also reduce dependence on coal, as well as the greenhouse gas emissions associated with coal use.  相似文献   

10.
The need for a rapid transformation to low-carbon economies has rekindled hydrogen as a promising energy carrier. Yet, the full range of environmental consequences of large-scale hydrogen production remains unclear. Here, prospective life cycle analysis is used to compare different options to produce 500 Mt/yr of hydrogen, including scenarios that consider likely changes to future supply chains. The resulting environmental and human health impacts of such production levels are further put into context with the Planetary Boundaries framework, known human health burdens, the impacts of the world economy, and the externality-priced production costs that embody the environmental impact. The results indicate that climate change impacts of projected production levels are 3.3–5.4 times higher than the allocated planetary boundary, with only green hydrogen from wind energy staying below the boundary. Human health impacts and other environmental impacts are less severe in comparison but metal depletion and ecotoxicity impacts of green hydrogen deserve further attention. Priced-in environmental damages increase the cost most strongly for blue hydrogen (from ~2 to ~5 USD/kg hydrogen), while such true costs drop most strongly for green hydrogen from solar photovoltaic (from ~7 to ~3 USD/kg hydrogen) when applying prospective life cycle analysis. This perspective helps to evaluate potentially unintended consequences and contributes to the debate about blue and green hydrogen.  相似文献   

11.
Adding wind power generation in a power system changes the operational patterns of the existing units due to the variability and partial predictability of wind power production. For large amounts of wind power production, the expectation is that the specific operational costs (fuel costs, start-up costs, variable operation and maintenance costs, costs of consuming CO2 emission permits) of the other power plants will increase due to more operation time in part-load and more start-ups. The change in operational costs induced by the wind power production can only be calculated by comparing the operational costs in two power system configurations: with wind power production and with alternative wind production having properties such as conventional production, that is, being predictable and less variable. The choice of the characteristics of the alternative production is not straightforward and will therefore influence the operational costs induced by wind power production. A method is applied for calculating the change in operational costs due to wind power production using a stochastic optimisation model covering the power systems in Germany and the Nordic countries. Two cases of alternative production are used to calculate the change in operational costs, namely perfectly predictable wind power production enabling the calculation of the costs connected to partial predictability and constant wind power production enabling the calculation of the operational costs connected to variability of wind power production. A 2010 case with three different wind power production penetration levels is analysed.  相似文献   

12.
An assessment is presented on hydrogen production using a dedicated central receiver solar system concept coupled to two types of hydrogen producing processes, electrolysis and thermochemical. The study on solar electrolytic hydrogen was carried out using solar electricity and four different electrolytic technologies, namely industrial unipolar 1980 and 1983 technologies, industrial bipolar and solid polymer electrolyte technology. The thermochemical process was the sulphur/iodine cycle which is being developed by General Atomic Co. Systems which is capable of producing about 106 GJ hydrogen per year were developed at the conceptual level and site specific computations were carried out. A general mathematical model was developed to predict the optical and thermal performance of the central receiver system coupled directly to the chemical plant. Cost models were developed for each sub-system based on the database published in the literature. Levelized and delevelized costs of solar hydrogen were then computed.  相似文献   

13.
In this paper, cost-benefit analysis is performed to compare eight different hydrogen production technologies using the classical analytic hierarchy process (AHP) and the Fuzzy AHP. The technologies considered are steam methane reforming, coal gasification, partial oxidation of hydrocarbons, biomass gasification, photovoltaic-based electrolysis, wind-based electrolysis, hydro-based electrolysis, and water splitting by chemical looping. For each of the hydrogen production technologies, five criteria are used for evaluation: greenhouse gas emissions, raw material and utilities consumption, energy efficiency, scalability, as well as waste disposal and atmospheric emissions. The results obtained for benefits category using AHP and Fuzzy AHP are plotted against the normalized equivalent annual costs of each technology. It is concluded that the fossil fuel based processes appear to have less beneficial qualities including greater environmental impacts, but are more cost-effective. On the other hand, the renewable based processes appear to have more benefits as well as being more expensive for hydrogen production. However, the cost-benefit analysis results imply that the process of water splitting by chemical looping among the renewable approaches is the most promising new technology.  相似文献   

14.
The current and future costs of willow short rotation coppice production in Sweden are analysed, considering all relevant cost factors explicitly. The future production costs are estimated considering effects of coppice area expansion and learning. The current and future costs of land and of risk premiums are subsequently estimated. Subsidies for farmers are not considered. If the area of willow cultivation were to expand enough to generate economies of scale, the production cost could be cut by about 10% compared to the current level. When learning effects are also considered, the total cost reduction potential is about 35%. Two major cost components (fertilization and road transport) are roughly stable while two other major cost components (establishment and harvest) have larger prospects for cost reduction, primarily due to potential for learning. Land costs and risk premiums vary and are uncertain, but both are estimated to be potentially significant compared to other cost components. Requirements of risk premiums may become lower as a consequence of area expansion and learning. Land costs are subject to many factors that are inherently uncertain, not the least future food prices. Efficient policies promoting an expansion of willow cultivation are discussed.  相似文献   

15.
This research examines the potential of producing hybrid poplar on location specific marginal agricultural lands in Minnesota. It is assumed that all poplar production would be used to meet biomass energy requirements for two potential 100 MW power plants located in Alexandria and Granite Falls, Minnesota. The delivered fuelwood costs for each power plant are calculated using a cost minimization model. In addition to traditional production and harvesting costs, the model also incorporates landowners opportunity cost of fuelwood production as well as the actual transportation costs associated with supply from each individual analysis area to each power plant. The inclusion of any analysis area as a potential fuelwood supplier is greatly dependent on the interaction and combination of variables such as the opportunity cost, yield rates, and the distance from the power plants. The results show that approximately 40×103 hectares of land capable of producing about 3.2×10[6] dry Mg of wood would be required to fuel each power plant for a 10 year planning period. The average present value costs of delivered (to the plant gate) fuelwood is about $32 dry Mg−1 for Alexandria and $37 dry Mg−1 for Granite Falls.  相似文献   

16.
The present work investigates the synthesis of a new and highly efficient sodium‐doped nanohydroxyapatite, as a heterogeneous catalyst for the production of fatty acid methyl esters from Schizochytrium algae oil. Sodium nitrate supported on nanohydroxyapatite catalyst was prepared using wet impregnation technique and calcinated at different temperatures. The synthesized nanocatalyst was characterized to determine the structural and morphological properties, using BET, XRD, TGA, FTIR, ICP, and TEM. Characterization results reported that the catalyst calcinated at 900°C exhibits good catalytic property. The catalyst was utilized for the production of biodiesel, under different reaction parameters through transesterification process. Response surface methodology (RSM) and artificial neural network (ANN) were employed to evaluate the best combination of molar ratio, catalyst concentration, and reaction time for transesterification process. By using point prediction method, the optimum yield of 96% was achieved at the catalyst concentration of 9.5 wt% of oil, 1:12 molar ratio, and 121‐minute reaction time. The physiochemical properties of the biodiesel were determined, and the result suggested that the biodiesel produced met ASTM D6751 standard. The catalyst exhibits good catalytic performance on reusability up to six runs without the loss of molecular activity. Therefore, the synthesized heterogeneous catalyst derived from animal bone could be efficiently used for the biodiesel production.  相似文献   

17.
The use of hydrogen is increasing in many countries due to potential decarbonization and sustainable energy transition projects. Hydrogen is shown to be a versatile transition alternative in different applications, with an increasing trend towards clean alternatives with better performance improving the existing processes. This paper reviews (i) the international panorama of hydrogen production, (ii) the main alternatives for hydrogen production in Mexico, and (iii) the applications of hydrogen in various areas. The challenges and opportunities for the coming years to include and introduce the use of hydrogen in new and existing processes in Mexico are also analyzed. A great variety of alternatives to procedure hydrogen both in Mexico and on the international scenes are analyzed, contemplating different production mechanisms. Many of them are found to require further studies to make them profitable for industrial applications. Some challenges and opportunities are also analyzed, showing the importance of synchronizing the public-private partnership agenda on hydrogen production, and to provide the most favorable conditions for investment attraction and development. This review shows that Mexico has the opportunity to make a decisive incursion into hydrogen production.  相似文献   

18.
This article studies the opportunity for producing hydrogen via alkaline electrolysis from electricity consumption during off-peak periods. Two aspects will be discussed: electricity spot markets and nuclear electricity production in France.

From a market point of view, when there is a significant fluctuation in electricity prices, the use of an electrolysis installation during off-peak periods makes it possible to make quite considerable savings in production costs. Savings vary enormously from one market to the next; some highly fluctuating markets offer very low off-peak prices and allow for viable hydrogen production, even if average electricity prices first appear to be quite high. Very fluctuating spot prices market may be difficult to predict and makes operations of an electrolysis installation more complicated and risky. For other more stable markets, the use of an electrolysis installation during off-peak periods does not appear to be a relevant proposition.

From the point of view of French electricity production, the availability of current nuclear power plants and the estimation of available energy for mass production of hydrogen show that the installations studied would not be viable. For “peak period” use, it would certainly be more useful to have electrolysers with a lower investment proportion, even if this means slightly higher operating costs. Research into large-capacity electrolysers should, therefore, both develop low-production-cost electrolysers, for use in base load mode where dedicated production means are concerned, and highly flexible electrolysers, with low investment costs, which could easily be viable with low rates of use.  相似文献   


19.
The development of cleaner and renewable energy sources are needed in order to reduce dependency and global warming. Wood pellets are a clean renewable fuel and has been considered as one of the substitutes for fossil fuels. In Argentina, large quantities of sawmill residues are still unused and wood pellets production could be seen as both, as an environmental solution and an extra economical benefit. The general aim of this study was to determine the wood pellets production costs and energy consumption under different framework conditions in northeast Argentina. The specific costs of wood pellets for the different scenarios showed relative lower costs comparing to the ones reported in other studies, ranging from 35 to 47 €/Mgpellets. Raw material costs represented the main cost factor in the calculation of the total pellets production costs. A lower specific production cost was observed when 50% of the raw material input was wood shavings. The specific electricity consumption per metric ton of pellet was lower in scenarios with higher production rate. Lower heat energy consumption was observed in scenarios that have a mixed raw material input. The most promising framework condition for Northeast Argentina, in terms of costs effectiveness and energy consumption could be acquired with production rates of 6 Mg/h with sawdust and wood shavings as raw material. However, simultaneous increment of the electricity by 50% and raw material price by 100% may increase the specific costs up to 50%.  相似文献   

20.
Because of biomass's limited supply (as well as other issues involving its feeding and transportation), pure biomass plants tend to be small, which results in high production and capital costs (per unit power output) compared with much larger coal plants. Thus, it is more economically attractive to co‐gasify biomass with coal. Biomass can also make an existing plant carbon‐neutral or even carbon‐negative if enough carbon dioxide is captured and sequestered (CCS). As a part of a series of studies examining the thermal and economic impact of different design implementations for an integrated gasification combined cycle (IGCC) plant fed with blended coal and biomass, this paper focuses on investigating various parameters, including radiant cooling versus syngas quenching, dry‐fed versus slurry‐fed gasification (particularly in relation to sour‐shift and sweet‐shift carbon capture systems), oxygen‐blown versus air‐blown gasifiers, low‐rank coals versus high‐rank coals, and options for using syngas or alternative fuels in the duct burner for the heat recovery steam generator (HRSG) to achieve the desired steam turbine inlet temperature. Using the commercial software, Thermoflow®, the case studies were performed on a simulated 250‐MW coal IGCC plant located near New Orleans, Louisiana, and the coal was co‐fed with biomass using ratios ranging from 10% to 30% by weight. Using 2011 dollars as a basis for economic analysis, the results show that syngas coolers are more efficient than quench systems (by 5.5 percentage points), but are also more expensive (by $500/kW and 0.6 cents/kW h). For the feeding system, dry‐fed is more efficient than slurry‐fed (by 2.2–2.5 points) and less expensive (by $200/kW and 0.5 cents/kW h). Sour‐shift CCS is both more efficient (by 3 percentage points) and cheaper (by $600/kW or 1.5 cents/kW h) than sweet‐shift CCS. Higher‐ranked coals are more efficient than lower‐ranked coals (2.8 points without biomass, or 1.5 points with biomass) and have lower capital cost (by $600/kW without using biomass, or $400/kW with biomass). Finally, plants with biomass and low‐rank coal feedstock are both more efficient and have lower costs than those with pure coal: just 10% biomass seems to increase the efficiency by 0.7 points and reduce costs by $400/kW and 0.3 cents/kW h. However, for high‐rank coals, this trend is different: the efficiency decreases by 0.7 points, and the cost of electricity increases by 0.1 cents/kW h, but capital costs still decrease by about $160/kW. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

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