The impact of carbon sequestration on the production cost of electricity and hydrogen from coal and natural-gas technologies in Europe in the medium term

Carbon sequestration is a distinct technological option with a potential for controlling carbon emissions; it complements other measures, such as improvements in energy efficiency and utilization of renewable energy sources. The deployment of carbon sequestration technologies in electricity generation and hydrogen production will increase the production costs of these energy carriers. Our economic assessment has shown that the introduction of carbon sequestration technologies in Europe in 2020, will result in an increase in the production cost of electricity by coal and natural gas technologies of 30–55% depending on the electricity-generation technology used; gas turbines will remain the most competitive option for generating electricity; and integrated gasification combined cycle technology will become competitive. When carbon sequestration is coupled with natural-gas steam reforming or coal gasification for hydrogen production, the production cost of hydrogen will increase by 14–16%. Furthermore, natural-gas steam reforming with carbon sequestration is far more economically competitive than coal gasification.     

Analysis of the cost of hydrogen infrastructure for buses in London

The use of hydrogen (H₂) as transport fuel is often said to suffer from the ‘chicken and egg’ problem: vehicles that depend on H₂ cannot go on the roads due to the lack of an adequate infrastructure, and the almost non-existent fleet of H₂ vehicles on the roads makes it economically unsound to build a H₂ infrastructure.Although both hydrogen vehicles (fuel cell and internal combustion engine) and the related infrastructure have been (and are being) developed and some are commercially available, cost is seen as a major barrier. With today's technologies, H₂ only becomes competitive with petrol and diesel when produced at large quantities, suitable for supplying e.g. thousands of H₂ buses. The question is, how might this point be reached, and are there least cost infrastructural pathways to reach it. This paper tries to address the latter question, using the early development of a H₂ infrastructure for buses in London as a case study.The paper presents some of the analyses and results from a Ph.D. project (in progress) being undertaken at Imperial College London, funded by EPSRC (Grant GR/R50790/01). The results presented here illustrate that cost of hydrogen production and delivery vary mainly with levels of hydrogen demand and delivery distances, as well as other logistic criteria; least cost production–delivery pathways have been identified for various hydrogen demand scenarios and refuelling station set-ups. Another important conclusion is that the pattern of converting a group of refuelling stations to hydrogen (e.g. a group of refuelling stations for buses in London) has a significant effect on the unit cost of hydrogen.     

A comparative techno-economic and quantitative risk analysis of hydrogen delivery infrastructure options

The comparative techno-economic analysis and quantitative risk analysis (QRA) of the hydrogen delivery infrastructure covering the national hydrogen demands are presented to obtain a comprehensive understanding of the infrastructure of commercial hydrogen delivery. The cost calculation model, which was based on the hydrogen delivery scenario analysis model (HDSAM), was employed to estimate the costs of hydrogen fuel delivery in Seoul, Korea, whose area is small enough to not require intermediate delivery stations. The QRA methodology was modified to be suitable for the comparative analysis of the whole hydrogen infrastructure. The capacities of a hydrogen refueling station and the hydrogen market penetration were employed as the main variables and the two scenarios, viz. the gaseous and liquid hydrogen delivery options, were considered. The analysis results indicate that the delivery system of gaseous hydrogen was superior in terms of cost and that of liquid hydrogen was superior in terms of safety. Both delivery options were affected by the capacity of the station and the market penetration, and the cost and risk drastically changed, especially when the two variables were small. Thus, according to the results, the economic and safety issues of the hydrogen delivery infrastructure are critical to achieving a hydrogen energy society.     

Storage and evolution of hydrogen in acidic medium by polyaniline

Emeraldine salt of polyaniline‐coated copper substrate was used as a cathode to study hydrogen evolution reaction in 1M H₂SO₄. Hydrogen evolution reaction in acidic medium followed Grotthus mechanism, where proton hops randomly on the surface of polyaniline. With Randles‐Sevcik equation, the average value of diffusion coefficient for H⁺ on polyaniline was calculated to be 2.66 times higher than that in the literature data. This higher value explicitly supported the rapid diffusion of H⁺ on polyaniline surface from the bulk electrolyte solution. With the help of a phenomenological thermodynamic approach demonstrated elsewhere, the solvent‐modified work function of polyaniline‐coated copper in acidic medium was calculated. The plot of exchange current density versus solvent‐modified work function of different metals and polyaniline‐coated copper indicated that at lower work function polyaniline‐coated copper showed higher exchange current density and the rate of hydrogen evolution was much higher on polyaniline‐coated copper than on copper. This was further confirmed by gas chromatography, and ¹³C and ¹H nuclear magnetic resonance studies supported the mechanism proposed. From linear sweep voltammetry analysis, it was observed that the total capacity of hydrogen stored on polyaniline‐coated copper was approximately 1.85 times higher than that on copper.     

Techno-economic assessment of hydrogen production processes for the hydrogen economy for the short and medium term

Hydrogen is expected to play a significant role in the future energy system. A key enabler to a hydrogen-including economy will be the development and deployment of processes that can produce hydrogen whilst satisfying the criteria for sustainability, i.e. economic competitiveness, environmental protection and security of energy supply. This paper evaluates selected hydrogen production processes based on natural gas steam reforming, coal and biomass gasification and water electrolysis. These options are expected to play a significant role in the short to medium term. Industrial large-scale processes, using natural gas and coal, will constitute the most important routes. However, increasing prices for natural gas are likely to make coal gasification more competitive. Biomass gasification could become important if present technological barriers are overcome. Electrolytic hydrogen, however, will likely be practical for niche applications in the short term due to the high electricity costs, especially when electricity is generated by renewable energy sources.     

Mobile phone infrastructure development: Lessons for the development of a hydrogen infrastructure

The development of new infrastructure is often a consideration in the introduction of new innovations. Currently there is some confusion around how to develop a hydrogen infrastructure to support the introduction of FCVs. Lessons can be learned from similar technology introduction in the past and therefore this paper investigates how mobile phone infrastructure was developed allowing the mass-market penetration of mobile phones. Based on this successful infrastructural development suggestions can be made on the development of a hydrogen infrastructure. It is suggested that a hydrogen infrastructure needs to be pre-developed 3–5 years before the market introduction of FCVs can successfully occur. A lack of infrastructural pre-development will cause to the market introduction of FCVs to fail.     

Polyaniline coated copper for hydrogen storage and evolution in alkaline medium

Emeraldine Hydrochloride salt is coated on copper substrate and studied for hydrogen storage and hydrogen evolution reaction in 1 M NaOH. Phenomenological thermodynamic approach demonstrated elsewhere in conjunction with the cyclic voltammetry data is employed to calculate the solvent modified work function for polyaniline coated copper in alkaline medium as ?0.65 eV. The solvated work function is in satisfactory agreement with the band gap difference of π?π* transition in emeraldine base and π- polaron transition in emeraldine salt ca ?0.6 eV as reported in the literature. ¹³C and ¹H NMR studies revealed that polyaniline undergoes switching between emeraldine salt and emeraldine base, before and after hydrogen evolution respectively. The volume of hydrogen evolved on polyaniline coated copper is 1.64 times than that on copper as demonstrated by Gas chromatography. Thus emeraldine salt, when stored in NaOH act as hydrogen storage medium and upon electrochemical perturbation can release hydrogen at controlled rate depending on the scan rate employed.     

The question of the hydrogen infrastructure for motor vehicles

The hydrogen supply for motor vehicles is not necessarily connected with the development of its own infrastructure in the form of hydrogen pipeline networks. It can be shown that the existing infrastructures for electricity, gas and water for centralized and decentralized generation of hydrogen can be utilized practically in terms of energy. The technical possibilities for decentralized generation of hydrogen and its use as an auxiliary fuel to extend the gasoline supplies are described and discussed.     

Risk analysis for the infrastructure of a hydrogen economy

Increasing scarcity of fossil fuels makes the deployment of hydrogen in combination with renewable energy sources, nuclear energy or the utilization of electricity from full time operation of existing power stations an interesting alternative. A pre-requisite is, however, that the safety of the required infrastructure is investigated and that its design is made such that the associated risk is at least not higher than that of existing supplies. Therefore, a risk analysis considering its most important objects such as storage tanks, filling stations, vehicles as well as heating and electricity supplies for residential buildings was carried out. The latter are considered as representative of the entire infrastructure. The study is based on fault and event tree analyses, wherever required, and consequence calculations using the PHAST code. The procedure for evaluating the risk and corresponding results are presented taking one of the objects as an example.     

Pathways to a hydrogen fuel infrastructure in Norway

Hydrogen is expected to become an integral part of the Norwegian energy system in the future, primarily as transportation fuel. The NorWays project aims at providing decision support for introduction of hydrogen in the Norwegian energy system by modelling of energy system and hydrogen infrastructure at various spatial levels. GIS-based regional hydrogen demand scenarios and fuelling station networks have been generated, considering organic growth of regional hydrogen coverage and increasing density of hydrogen users over time. A regional model optimised supply scenarios for these fuelling station networks, including choice of production technology (biomass gasification, NG SMR, electrolysis, by-product hydrogen) and delivery (pipeline, truck, and onsite schemes), including integrated hydrogen delivery networks by truck and pipeline. The impact of energy price and GHG emission constraint scenarios on hydrogen production and delivery mix and average hydrogen costs is analysed, and conclusions on the effectiveness of policy measures are drawn.     

山西煤基替代石油中长期发展战略研究

山西是我国重要的煤炭基地,实施煤基替代石油战略是保障国家能源安全,建设国家新型能源基地,培育煤炭接续产业的必然选择。根据国家替代能源中长期发展战略和山西省的省情,提出了立足于丰富的劣质煤、焦炉煤气、煤层气等资源优势,推进包括煤基醇醚燃料、煤制油、水煤浆等替代能源的多元化发展战略,并提出了相应的政策建议。     

The role of hydrogen for the long term development of sustainable energy systems—a case study for Germany

Based on different current long-term energy scenarios the paper discusses the future perspectives of hydrogen in the German energy system as a representative example for the development of sustainable energy systems. The scenario analysis offers varying outlines of the future energy system that determine the possible role of hydrogen. The paper discusses the possibilities of expanding the share of renewable energy and the resulting prospects for establishing clean hydrogen production from renewable energy sources. Emphasis is given to the questions of an ecologically efficient allocation of limited renewable energy resources that can only be assessed from a systems analysis perspective. Findings from recent studies for Germany reveal a strong competition between the direct input into the electricity system and an indirect use as fuel in the transport sector. Moreover, the analysis underlines the paramount importance of reducing energy demand as the inevitable prerequisite for any renewable energy system.     

An options approach to investment in a hydrogen infrastructure

This paper discusses the investments needed for the introduction of hydrogen as a transport fuel. Using option theory, we develop a model to calculate the value and optimal timing of a first commercial rollout of hydrogen vehicles in a larger area, taking Japan as a specific example. We find that the project is best viewed as an out-of-the-money call option with a small but positive option value. We estimate this value at approximately 1.5 billion euros, without tax advantages. An important finding is that the moment of investment is first and foremost determined by the maturing of the technology. By contrast, the investment timing is not as much affected by deployment strategy as is frequently thought: in particular, whether or not the hydrogen retail infrastructure is introduced smoothly does not sensitively influence the investment timing. Fairly independent of parameter assumptions, the project value at the moment of deployment is negative for the retailer and positive for the car manufacturer. This implies the need for a negotiated partnership. Finally, we assess various forms of government support, e.g. subsidies or tax cuts. Looking at the effectiveness of this support spending in relation to the advancement of hydrogen deployment, we find, again because investment timing is primarily determined by technology maturation, that tax incentives are relatively ineffective. We are lead to believe that government subsidy for technology development is a more effective means to achieve earlier investment, as faster production cost reductions for hydrogen and fuel cell vehicles lead to accelerated investment.     

The use of the natural-gas pipeline infrastructure for hydrogen transport in a changing market structure

In this paper, the transport and distribution aspects of hydrogen during the transition period towards a possible full-blown hydrogen economy are carefully looked at. Firstly, the energetic and material aspects of hydrogen transport through the existing natural-gas (NG) pipeline infrastructure is discussed. Hereby, only the use of centrifugal compressors and the short-term security of supply seem to constitute a problem for the NG to hydrogen transition. Subsequently, the possibility of percentwise mixing of hydrogen into the NG bulk is dealt with. Mixtures containing up to 17 vol% of hydrogen should not cause difficulties. As soon as more hydrogen is injected, replacement of end-use applications and some pipelines will be necessary. Finally, the transition towards full-blown hydrogen transport in (previously carrying) NG pipelines is treated. Some policy guidelines are offered, both in a regulated and a liberalised energy (gas) market. As a conclusion, it can be stated that the use of hydrogen-natural gas mixtures seems well suited for the transition from natural gas to hydrogen on a distribution (low pressure) level. However, getting the hydrogen gas to the distribution grid, by means of the transport grid, remains a major issue. In the end, the structure of the market, regulated or liberalised, turns out not to be important.     

Small and medium size drum boiler models suitable for long termdynamic response

Data and control schemes for small and medium size drum boiler models are presented. Methods and field tests for the data evaluation are included. Simulation of the model response against megawatt response field tests are also included. The resulting errors due to measurement inaccuracies and model simplification, and the applied procedure for data evaluation are also presented. The size of the boilers partially solved the data problem which limited the applicability of the low-order models (LOMs). The LOM parameter and associated standard deviation obtained via the plant probes depict the variable conditions with which the controller is faced. The obtained data are useful for controller synthesis and tuning, especially for control logics which utilize a simplified boiler model as part of their control law     

The effect of 3D silver nanodome size on hydrogen evolution activity in alkaline solution

Three-dimensional (3D) Ag nanodomes (AgNDs) having different sizes (400, 800, 1200 and 1600 nm) were fabricated using combination of nanosphere lithography and soft lithography. The surface structures of 3D assembled latex particles, nanovoids and metal nanodomes (ND) were examined using scanning electron microscopy (SEM). Their heights and widths analyses were performed with the help of atomic force microscopy (AFM). The effect of diameter of the NDs on their hydrogen evolution activity was examined in 6 M KOH solution at 298 K using electrochemical techniques. Their activities were compared with the activity of bulk Ag electrode. The preparation of 3D-AgNDs having various diameters and examination of their size effects on the water splitting activity have not been studied yet and are being reported firstly. It was found that very well-structured and very uniformly distributed NDs can be fabricated using this procedure. AgNDs exhibit higher hydrogen evolution activity with respect to bulk Ag. Their hydrogen evolution activity depends on their diameters; 1200 nm NDs were the best among them. The current density at ?1.40 V(Ag/AgCl) which is proportional to the rate of hydrogen releasing reaction increases from 0.70 mA cm^?2 to 44.13 mA cm^?2 at this ND electrode with respect to the bulk Ag electrode. At the same 3D-AgNDs electrode and potential, the resistance against the HER reduces from 148.7 Ω cm² to 1.12 Ω cm² (99.6%) by comparing with the bulk Ag electrode. The average surface roughness factors of bulk Ag, 400 nm, 800 nm, 1200 nm and 1600 nm AgNDs are 8, 123, 100, 291 and 176, respectively. The superior hydrogen evolution performance of this electrode is related to its well-structured surface and large real surface area.     

Derivation of method for predicting long term average energy delivery of solar collectors

Based on the utilizability concept of Hottel, Whillier, Liu and Jordan, an analytical model has been developed to predict the long term average energy delivery of almost any solar collector. The presentation has been split into two separate papers: a users guide (without explanation of the origin of the formulas) and the present paper (which derives these formulas and documents the validation). The model is applicable whenever the average operating temperature of the collector (receiver surface, fluid inlet, fluid outlet or mean fluid) is known. If the operating temperature is not known explicitly the model will give adequate results when combined with the , f-chart of Klein and Beckman. By contrast to the alternative of hour-by-hour simulation, prediction methods such as the present model and the f-chart offer the advantages of automatically averaging over year-to-year weather fluctuations and of being sufficiently simple to permit hand calculation of long term performance. In a comparison with hourly summations of insolation data, the present model has been found to have an error of less than 3 per cent for the radiation available to a solar collector and an error of about 5 per cent for the heat delivery of solar thermal collectors.     

The cost of hydrogen from coal

Isolation of the hydrogen and oxygen plants from the rest of the liquefaction complex, combined with appropriate transfer costs for all utilities and raw materials has been used to estimate the value of hydrogen. For the five alternatives, minimum cost hydrogen is produced by gasification of coal at 1000 psia. 500 psia gasification of coal yielded slightly more expensive hydrogen; however, on an equivalent mole basis of hydrogen, they were virtually the same. As would be expected, the cost of coal, discount cash flow rate and method of costing supplemental fuel needs were the primary variables affecting the cost of hydrogen. Hydrogen cost ranged from $0·847/1000 standard cubic feet to $2·986/1000 standard cubic feet.     

Towards a sustainable hydrogen economy: Hydrogen pathways and infrastructure

Results from the European HySociety project (2003–2005) are revealed in which political, societal and technical challenges for developing a European hydrogen economy have been addressed. The focus is placed on the assessments of hydrogen pathways and infrastructure. It will show that no chain can be selected as an obvious winner according to primary energy demand, emission and cost. In order to ensure that the pathway losses are compensated by the more efficient end-use of the H₂ fuel, calculations based on well-to-tank losses and tank-to-wheel efficiencies are used. Furthermore, in order to look into the consequences of introducing hydrogen, a top-down scenario has been worked out. The message is that certainly the hydrogen distribution part for the transport application has to be improved to avoid loosing the emission gain that is obtainable, especially via carbon capture and storage of the CO₂. In order to quantify the market development a bottom-up approach has been established in particular for the transport sector.