Final Report Summary - HYDROSOL-3D (Scale Up of Thermochemical HYDROgen Production in a SOLar Monolithic Reactor: a 3rd Generation Design Study)
Executive Summary:
HYDROSOL-3D’s main objective was to deliver not only concepts but also a detailed design including all necessary and appropriately sized components for the construction of a 1MWth demonstration plant for the solar thermochemical H2 production from the splitting of water in monolithic reactors. This was possible since the technology was already developed in the earlier projects (HYDROSOL, HYDROSOL-II) up to a stage (100 kW) which is with respect to maturity, size, and layout close to what is expected for a demonstration plant. HYDROSOL-3D covered the remaining measures necessary to lead the technology to a demonstration and to prepare such plant in detail.
During the three years of the project “fine tuning” of redox materials’ compositions led to the selection of three potential promising candidates. A further refinement of the kinetic models was achieved that provided a full description of the whole extent of the water splitting and thermal reduction reactions. Furthermore, porous structures consisting entirely of the redox material were manufactured and were active water splitters. A new reactor design was proposed that was optimized towards lower thermal losses and more homogeneous temperature distribution compared to the designs employed in the predecessors of the HYDROSOL-3D project. The reactor and the whole periphery were laid out. The process flexibility allows its installation on already existing solar tower platforms. Additionally, a first Greenfield plant was developed with optimization of the heliostat field, the solar tower and other components for a specific location in southern Spain. For the purification of the produced H2, a purification unit based on Pressure Swing Adsorption (PSA) was designed and successfully deployed. A control algorithm was designed to control the solar reactors’ temperature, and showed promising results in controlling the temperature by varying the number of heliostats. Significant trends and recommendations were elaborated from experimental campaigns with the HYDROSOL-II solar receiver-reactors, a test campaign on new redox coated monoliths indicated long‐term cyclic operation stability and high H2 yield under operation at high temperature solar irradiation.
In parallel, the most promising option of a plant scenario was selected. The complete plant was laid out and all relevant components were sized. The heliostat field and tower design were optimized with respect to installation costs and overall plant efficiency. The control system, the sensors and actuators of the process were defined by reviewing and selecting commercial solutions available at and adaptable from the market.
The techno-economic analysis showed that the total investment requirement for adapting an already existing concentrating solar platform facility is approximately 3 times lower than constructing a new 1MWth demonstration plant. In the case of H2 production and supply cost the analysis was conducted for the 21MW commercial plant and the estimated cost of production was on the average within a factor of 2-2.5 of the cost of non-renewable routes without considering taxes/benefits. However, in the mid to long-term, cost of hydrogen production from non-renewable paths is expected to rise with the increase of the cost of fossil fuels and the possible introduction of stringent environmental taxes. In parallel, improvements in the field of solar technologies (e.g. heliostat cost, heliostat’s tracking system and solar field optimization), would significantly reduce the gap and bring the HYDROSOL technology closer to the competitiveness of non-renewable routes, while remaining competitive with regards to photovoltaic supplied electrolysis. So, from the cost point of view, the market deployment scenarios could target any hydrogen market. The Hydrosol technology could take a visible share of this market in the long-term, especially alongside Fuel Cell Vehicles deployment.
Project Context and Objectives:
HYDROSOL-3D was scheduled as a 3-year Collaborative Project. The principal objective of HYDROSOL-3D is the in-detail preparation of a plant for solar thermo-chemical H2 production from H2O in a 1 MW solar tower.
Capitalizing on the predecessor Projects HYDROSOL and HYDROSOL-II that have introduced the concept of honeycomb monolithic solar reactors for H2 production from H2O splitting via redox-pair-based thermochemical cycles, HYDROSOL-3D focuses on the next step towards commercialisation and involves all activities necessary to prepare the erection of a HYDROSOL-technology-based 1 MW demonstration plant. In this respect HYDROSOL-3D is concerned with the complete pre-design and design of the whole plant including the solar reactor and all necessary upstream and downstream units needed to feed in the reactants and separate the products and the calculation of the necessary plant erection and H2 supply costs.
This design started with the fine-tuning of the materials’ composition and the reactor configurations advanced through the Projects HYDROSOL and HYDROSOL-II in order to ensure long-term, reliable solar-aided H2 production at industrially attractive yields. Designs and concepts that will enhance incorporation of redox material in the reactor and reduction of radiation losses were considered and implemented. In parallel, the control concepts, algorithms and procedures necessary for the operation of such a plant were developed and integrated in a process simulation software. The pre-design components and the control strategies were thoroughly validated by experiments spanning the whole reactors’ range: from small lab-scale reactors to pilot reactors coupled with solar tower facilities, in order to fully verify their transferability to large-scale operation. Two alternative plant scenario options were analyzed: i) adaptation of the H2 production plant to an existing solar field/tower facility and ii) development of a new completely optimised H2 production/solar plant “from scratch”. The most promising option was selected and analysed in detail, the complete plant layout was delivered, all necessary components were defined and sized, the control system was finalized and the operation of the whole plant was simulated. Finally, a techno-economic and market analysis determined the feasibility of the process scale-up to the MW scale, by calculating the cost of erection of a 1 MWth demonstration plant and the H2 production and supply costs for the case of an industrial scale plant of 21 MWth. Elaborated realistic scenarios for market penetration and on potential synergies with other technologies complemented the Project. The specific Scientific and Technical Objectives of HYDROSOL-3D were:
• Design and development of solar H2 receiver/reactors with enhanced transport, thermal and heat recovery properties.
• Design and development of prototype H2 drying units.
• Establishment of a reliable operational strategy to be applied in a sequential process (oxidation and reduction steps) at a solar receiver plant.
• Development of a simulation tool including the controllers, plant design and control algorithms in a commercial software toolkit for process engineering purposes.
• Optimization of process parameters in the pilot plant.
• Implementation of the control strategies and algorithms proposed in the specific process control system for the plant.
• Validation of operation of developed units, control system and reliability of plant design by laboratory and pilot plant testing.
• Identification of most suitable site and scenario for a demonstration.
• In-detail design of a 1MW demo plant.
• Conceptual design of the whole control system with commercial solutions from the market.
• Simulations of the best case studies with the commercial toolkit.
• Identification of investment and operational cost of a 1MW demo plant for two-step solar H2 generation.
• Presentation of a suitable strategy for the introduction of the technology into the market.
Project Results:
The HYDROSOL-3D project comprised of six work packages (WPs), with five of them being dedicated to its Research and Development (R&D) aspects and one related to its administrative management and dissemination. The main scientific and technological outcomes of the project, within its 3-year duration, are summarized below per WP. The titles of the R&D WPs and a brief description of their major objectives are also provided.
WP2: Refinement of core components and materials
Major objectives:
• Fine-tuning of metal oxide material properties
• Improvement of absorber/reactor structure and design
• Optimization of heat recovery inside the reactor and in the whole process
A systematic synthesis and testing study of different redox materials has helped to eliminate redox material compositions containing volatile elements and to adapt the synthesis and testing procedure towards the collection of reliable data for the extraction of the reaction kinetics. Redox material families targeted included ferrites, iron aluminates, iron chromites and ceria-zirconia. A systematic synthesis and testing study has eliminated several of these compositions due to thermal instability reasons, leaving eventually three materials as capable of cyclic hydrogen production and potential promising candidates for further parametric studies and comparative evaluation. Extensive parametric studies have shown that hydrogen yield depends both on the thermal reduction (TR) as well as on the water splitting temperature (WS). WS temperatures higher than a “threshold” value (i.e. at least 1000oC) improved hydrogen yield significantly; however increase of the water splitting temperature to 1100oC had no further favorable effect. A similar trend seems to exist with the TR temperature: an increase from 1250 to 1400oC has tripled the respective hydrogen yield at 1100oC. A mathematical model to describe the WS-TR reaction steps was formulated and was applied to to generate kinetic parameters from experimental results.
Several factors that can facilitate the access of the steam to the reaction sites and thus achieve higher hydrogen reaction rates and volumetric yields per cycle were investigated. Efforts to manufacture open-porosity foams entirely from mixed oxides were not successful, since problems with achievement of satisfactory “green foam body” mechanical strength without employing binder materials that react detrimentally with the active redox phase during sintering could not be resolved. The most worth investigating route to be pursued would be the manufacturing of the entire honeycomb reactor monolith from the redox material itself, in combination with increasing the monoliths’ cell density beyond that currently employed in an effort to increase the available gas-solid contact area.
The most important aspects of the actual reactor design that needed improvement in the next reactor generation were the reduction of thermal losses and the achievement of homogeneous temperature distribution within the honeycombs’ structure, maintaining at the same time the construction modularity.
The design was based on raytracing simulation results and experiences with the mini plants of the Hydrosol project and the pilot plant at the Plataforma Solar de Almeria of the Hydrosol-II project.
From the raytracing analysis it was concluded that the spherical absorber shape has the best performance and it would be used for the pre-design of the reactor. The new design that was proposed consisted of a hemispherical absorber and incorporated a secondary concentrator; their shape, geometry and dimensions were optimized.
Concerning heat recovery all heat streams and corresponding temperatures were identified and two heat exchangers to cover a large part of the possible heat recovery were proposed.
WP3: Pre-design of the control system and operational conditions of an 1MW demo-plant
Major objectives:
• Development of control concepts and procedures (including start-up and shut-down) and pre-design of a specific process control system
• Integration of in-house developed models for core components in process simulation software
• Complete pre-design of alternative plant scenario options (coupled to existing and to new solar field/tower facilities) and selection of most promising one for further in-detail analysis
A control system adjusted to the needs of the HYDROSOL-3D project was developed. Based on the experiments on HYDROSOL-II an additional analysis effort was made to extrapolate the behavior of the plant to the new concepts proposed in HYDROSOL-3D. This task aimed to provide detailed conclusions about the controllability issues of the process and conservative control and operation schemes for the new plant, addressing among others the switch between the two operational phases and aiming to minimize optical and thermal losses. Control procedures for the case of changeable weather conditions and failure of components were also developed and verified. This package proposed implementation of control strategies and control algorithms for the pre-design of the proposed specific process control system.
The controllers, plant design and control algorithms that were chosen in Task 3.1 were developed and implemented in a commercial simulation software tool for process engineering in Task 3.2. The first step was to develop a model of the whole system. Two main components were included in this model, the heliostat solar field and the reactor. Once the model was validated with real data, a control algorithm was designed in order to control the temperature in both reactors. This controller has been tested in simulation using the dynamic model of the plant.
Several advances have been included to control the main variables of the process, the temperature in the reactor. A control scheme which combines a feedforward and a feedback action has been proposed to obtain the desired response in the temperatures, rejecting disturbances in the main source of energy (the solar irradiance). Simulation evaluations showed promising results in controlling the temperature by varying the number of heliostats focused on the target.
Based on the original concept, which was decided in the 1st project period, the reactor has been designed. Furthermore, an optimization of the reactor shape has been executed so that in this case, the calculated heat losses are much lower than in the HYDROSOL-I and II systems. This is mainly because of the smaller ratio between the quartz window and the reactive surface. Another point for the reduced radiation losses is the cavity design in a football shape. The heat flux is distributed more homogenously in a spherical shape than in a flat design. This happens because the surface is irradiating onto itself.
Furthermore, the whole reactor body, with all separate parts was designed. In addition, several calculations about material strength, bond strength, and heat losses by conduction, irradiation and convection have been carried out. These calculations were optimized in special cases of use by the Aspen and MATLAB tools.
In addition, the whole periphery and the reactor itself were laid out. That means the storage tank and their shape, the power supply by open volumetric receiver, the piping, the evaporation process and the secondary concentrators with attached reactor modules were considered. The allocation of power for preheating, evaporation and superheating has been calculated that there can be more generated than needed during the process. Therefore, the pipelining between the storage tanks, the heat exchanger, the reactor modules, the separation and storage of the product gas were laid out.
The whole developed system could be installed onto the two existing platforms in Spain and Germany. For these cases, the solar towers have to be adapted. To avoid this and for future projects, a first Greenfield plant has been developed in which every single part of the system is optimized for the special use of hydrogen production via the HYDROSOL concept. Therefore, a certain location in the southern Spain has been considered and the heliostat field and solar tower were evolved exactly for this purpose.
WP4: Experimental validation of pre-design components and process strategies
Major objectives:
• Validation of pre-design components and process strategies by experiments (using prototypes and pilot plant in the laboratory, solar furnace, solar simulator and solar tower of the pilot plant)
• Development of operational strategies for specific (e.g. weather and day-time dependent) phases of the process as well as on a annual basis
A first experimental campaign has been dedicated to the qualification of redox materials exposed to simulated solar radiation. Non-solar and solar simulated experiments were conducted from the beginning of the 1st project period for the evaluation of redox material coated honeycombs. The so-called batch reactor developed earlier has been used for this purpose. Honeycomb samples coated with active redox material have been tested in this reactor in DLR’s high flux solar simulator (HLS) as well as in a laboratory set-up with an electric heated tube furnace for comparison. The HLS experimental test rig was employed for the evaluation of redox material coated small scale honeycombs under solar simulated conditions. The HLS with its actual technical abilities has got all flexibility necessary to provide temperature profiles needed to perform a thermo-chemical cycle. So that, it is possible to conduct experiments with simulated solar radiation under constant and reproducible conditions, independent to weather conditions. Some issues that were raised during the experimental campaign were the reactor leaks induced by the high temperatures, the insufficient and inhomogeneous gas flow through the channels of the honeycombs, and the unstable performance of the coated honeycombs. The second set of experiments was to operate each sample in five tests with different parameters (temperatures for regeneration and for water splitting, variation of regenerating time, variation of splitting time, variation of steam concentration and a combination of all best parameters). Four redox coated monoliths prepared by APTL with different loading characteristics were used. In the experiments with coated samples for hydrogen generation, all samples could generate hydrogen at 900°C, in small quantities. These experiments with the used samples have shown that hydrogen generation works at low temperatures, even though at low production rates. This was expected because the samples were already intensively treated under harsh conditions by the tests in the HLS and lost some of the coating in all the mounting and removal steps. These results reinforce the assumption that a lack of flooding to the samples in the HLS experiments caused the low amounts of hydrogen produced.
With respect to the evaluation of the redox materials in WP2, a systematic synthesis and testing study of different redox materials left eventually three compositions as potential promising candidates for further parametric studies and comparative evaluation. In parallel, experiments with varying steam mole fraction performed at APTL showed that the water splitting reaction can be considered to be first order with respect to steam concentration. Models linear with respect to the number of oxygen storage sites are proposed for both water splitting and thermal reduction reactions; however they follow the experimental hydrogen production reaction rate up to a reduction of about 30% of its initial value. After this point, the experimental rate sustains higher values than those predicted by the model, implying a variation of the reaction mechanism. The calculation of kinetic constants for the water splitting reaction has resulted in a very weak temperature dependence in the temperature region 700-1100oC studied so far. This fact indicates that perhaps the rate-controlling step is not a chemical reaction per se (for which an Arrhenius-type temperature dependence would be expected) but rather another, less strongly temperature-dependent step like the adsorption of steam molecules on the redox material surface. This assertion is compatible to the linear dependences of the reaction rate from steam concentration and oxygen storage sites. Regarding the thermal reduction kinetic constant, it is shown that there is no influence by the WS reaction temperature and there is an increase as the TR temperature increases. A complete picture of the WS-TR process has been revealed based on the findings of the present work and specific ways to further quantify the process are set forth. Further modeling of the reaction kinetics would require the complete hydrogen/oxygen production reaction rate curves up to the exhaustion of the gas products. For this reason, experiments that involved an increased duration of the activation, the water-splitting and the thermal reduction steps were conducted. In this way, the H2 and O2 concentration evolution curves up to the exhaustion of the storage sites were obtained. These set of experiments contributed to the derivation of a “refined” kinetic model that could describe more accurately the water-splitting and the thermal reduction process.
Furthermore, the manufacturing of porous structures consisting entirely of the redox material was achieved. The porous structures were capable for cyclic water splitting and thermal reduction. However, further investigation is needed for the optimization of the geometry of the structures and the enhancement of their performance.
In addition, for the purification of the produced hydrogen from the solar reactor, a hydrogen purification unit based on Pressure Swing Adsorption (PSA) was designed and successfully deployed. The next step to approve this technology as proper solution for the water/nitrogen removal out of the solar reactor’s effluent would be the assembly of a four-bed PSA for the continuous production of hydrogen. The future PSA would have to be at bigger sizes and directly integrated into the hydrogen production process using thermal water splitting over redox materials
The pilot plant including the two-chamber receiver-reactor installed at the SSPS solar tower of the PSA was used to carry out experimental campaigns for the validation of process strategies, simulation of control procedure and optimization of operational ranges and process parameters. The validation of the control software was conducted in the Hydrosol demonstration plant. The model of the system has been validated with real data. As a consequence, a simulation of the control process has been carried out with the aim of improving the process operation. Finally, an adaptive control strategy has been tested in the real plant. Furthermore, a significant number of hydrogen production cycles in several experimental campaigns were realized during the two project periods in the Hydrosol demonstration plant, demonstrating that optimization of operational parameters in HYDROSOL technology at pilot scale is viable. Potential operation ranges and the influence of key operation parameters were investigated.
Potential operation ranges and the influence of key operation parameters were investigated. It was observed that temperature of the hydrolysis step has a significant effect on the H2 yield. The effect of the duration of the water splitting is also significant. Different water-splitting/regeneration durations were examined. Although for shorter cycles the hydrogen yield per cycle is lower, for a standard reactor consisting of two modules, the Nº of cycles increase at the same extent and the daily hydrogen production is quite similar to that of the longer cycles. The final test campaign demonstrated the success of new monoliths coated with fine‐tuned redox material. The preliminary results indicate a long‐term cyclic operation stability and high H2 yield under operation at high temperature solar irradiation.
WP5: Design of a 1MW demo-plant
Major objectives:
• Detailed design study of complete demonstration plant
• Support of design by modeling and simulation
• Sizing and selection of all necessary peripheral components
• Simulation of core components and standard operation phases
• Simulation of controlling the process as a whole including transient operation phases
• Process integration
This work package contains two main tasks: The heliostat filed layout and the detailed reactor design. The most promising option of a plant scenario (introduced in WP3) was selected and analyzed in detail (the complete plant was laid out and all relevant components were defined and sized in detail).
The definition and description of the solar part was done by DLR using methods taken from the experience gained from the lay-out of solar power towers and using in-house-developed software tools dedicated to such purpose. This includes the selection of a suitable heliostat type and necessary foundations, supports and drives. The heliostat field, the receiver-reactor as the core-component as well as the most important balance-of-plant components have been designed and sized. As general approach a Greenfield plant was chosen because it offers the highest flexibility for designing the whole field, tower and reactor at a certain location. The components analyzed comprise heat exchangers, evaporators, pumps, the gas compression for the PSA, and the inert gas and hydrogen storage. The heat exchanger sizing was based on the results from the simulation analysis.
The heliostat field and tower design was optimized with respect to installation costs and overall plant efficiency with HFLCAL. A suitable heliostat type has been chosen. The heliostat field optimization considered the specifically newly designed reactor geometry and in particular the acceptance angle of the secondary concentrator attached to it.
The heat required for the evaporation, the preheating and superheating of the feed stream can be covered by “waste” heat from the product streams. No additional heat source is needed. Additional thermal receivers installed at the aperture of the tower to ensure an area-wide coverage of the whole receiver area can be used for generating power to run auxiliary unit or to be sold as “by-product”.
As input for a detailed sub-component selection and design the results from the process optimization on heat recovery potentials were needed, in particular for the selection, dimensioning and design of required heat exchangers. Additionally, the water demineralization and the evaporation unit, product gas treatment (hydrogen drying unit) and auxiliary system components like compressors, storages and piping were examined and calculated. This task also focused on the mimic for reactor positioning and movement. Results of this task were also linked to the cost analysis of the process in WP6.
Boundary conditions arising from the selected specific case are taken into consideration. The results served as a basis for the economic analysis of WP6.
Model aspects of the absorber structure and reactor with respect to the thermal behavior of the absorber-reactor under various operating conditions were investigated by developing a 3-dimensional representation of the reactor and employing Computational Fluid Dynamics analysis (CFD). Two cases were investigated: i) a reactor consisting of flow-through monoliths and ii) a reactor consisting of wall-flow monoliths.
In the first case high gradients were developed in the distribution of the temperature from monolith to monolith. This was attributed to the difference in the shapes of the monoliths (pentagons and hexagons) used in the reactor, that, in the case of the flow-through monoliths, induces the unevenness of the flow distribution. In the second case the lower permeability of the monoliths tends to smooth the gas velocities and therefore homogenize the temperature distribution between the monoliths.
In addition, 1D single channel simulation of the water splitting and the thermal reduction reactions was performed for a “representative” channel, employing the refined kinetic model that was derived in WP4. The parameters that were investigated were the redox capacity of the material, the amount of water vapor in the feed and the amount of material that is coated on the channel. By increasing water vapor concentration from 20 to 30% an increase in the production of H2 is also observed, while further increase of the concentration of water did not provide any significant positive effect in the H2 yield.
Furthermore, in the case of the process simulation, two simulations have been performed: i) for the 1 MWth demonstration plant and ii) for the 21MWth commercial plant.
The simulation involved all the major process components i.e. pumps, compressors, coolers, preheaters, superheaters, evaporators, heat exchangers, the solar reactors (one reactor in water splitting conditions and one reactor in regeneration conditions), the PSA unit, the H2 storage unit etc. Simulation results, such as mass flow rates, temperatures and pressures and the heat duty were extracted for all components. The layout of the flowsheets of the demonstration and the commercial plant is similar with the difference that in the case of the commercial plant an oxygen separation unit is also included, and the hydrogen storage is conducted at higher pressures by employing a 3-stage compression.
The yearly efficiency of the process was calculated for the case of the demonstration plant and was larger from that of other renewable pathways, such as production of hydrogen from electrolysis with the required energy produced from photovoltaics. Furthermore, integration of the process into a solar-thermal plant would be a value adding feature, since, along with the production of electricity, there would be also storage of energy into the produced hydrogen.
Once the whole process and the heliostats, the heliostat field, the tower and the receiver for the Hydrosol 3D pilot plant were defined and the control and operational strategies were proposed, the control system, the sensors and actuators of the process were defined by reviewing and selecting commercial solutions available at and adaptable from the market. Detailed hardware solution have been described and suggested for the process control, for the data acquisition, for the measurement and simulation of the solar flux, for the components of a meteorological station, for flow control, for components of the evaporation and superheating unit, of the hydrogen separation unit and of the hydrogen compression unit. The selection has been done to complete as far as possible the collection of information needed to define and prepare the set-up of a 1 MWth demonstration plant of the respective process with all necessary peripherals. The choice of control components took profit from the experience of the pilot plant set-up and testing at the Plataforma Solar de Almeria in the projects Hydrosol-II and Hydrosol 3D.
WP6: Techno-economic and market analysis
Major objectives:
• Case and sensitivity studies for selected sites
• Annual analyses with high time resolution
• Determination of techno-economic potential
• Determination of potential synergies with other technologies (e.g. water desalination, power generation)
• Cost estimation of investment of demonstration plant
• Evaluation of production and distribution cost
The cost of the plant’s components that have been sized based on the simulation results in WP5, was calculated for the case of the 1MW net thermal input demonstration plant. Two cases were analyzed regarding the equipment cost calculation and the total investment requirement: i) the general case of a new plant, which includes new design of the tower and the heliostat field, and ii) the extension of an already existing solar plant. In the last case, which refers to the solar tower of Jülich (Germany), the tower and the heliostat field do not need to be re-designed.
The solar part of the plant represents about 63 % of the total equipment cost due to the higher costs of the heliostats. The total investment requirement of the new demonstration plant has been estimated to be more expensive by a factor of 3 compared to the second case of the adaptation of an existing solar plant to the HYDROSOL 3D process.
In the economical evaluation of the Hydrosol technology for the generation of green hydrogen the main features of the design of a “first of a kind” industrial-size (21MW net thermal input commercial plant) hydrogen generation unit were summarized and the methodology used for the hydrogen production cost estimate was described. The cost calculations for current economical conditions were then presented and the results commented. In particular, the impact on the hydrogen production cost of other possible scenarios was discussed (scale of the plant, location, etc) and the range of production costs covering all these scenarios was presented. The estimated cost of production was on the average within a factor of 2-2.5 of the cost of non-renewable routes without considering taxes/benefits. Cost reduction approaches lay mainly on improvements in solar tower technology, heliostat’s tracking system and solar field optimization.
Regarding the supply of hydrogen, it can be transported as a compressed gas, a cryogenic liquid or as a solid metal hybrid. For large quantities of hydrogen, hydrogen delivery via pipelines is cheaper than all other methods except in the case of transport over an ocean, in which liquid hydrogen transport would be cheapest. Transportation of hydrogen at long distances for energy use may not be economically competitive. Transportation, distribution and refueling stations may add some 0.46-1.12€/kg to the H2 production cost.
Finally, a market analysis was performed that identifies and quantifies the markets that can be addressed by the Hydrosol 3D process in the mid to long term period. Realistic scenarios were built for the initial market introduction, followed by a real market deployment. The Hydrosol 3D process is considered either stand-alone or in synergy with another process when this brings a technical and/or economical advantage.
In the mid to long-term, cost of hydrogen production from non-renewable paths is expected to rise with the increase of the cost of fossil fuels and the introduction of stringent environmental taxes. In parallel, improvements in the field of solar technologies (e.g. heliostat cost, heliostat’s tracking system and solar field optimization), would significantly reduce the gap and bring the HYDROSOL technology closer to the competitiveness of non-renewable routes, while remaining competitive with regards to photovoltaic supplied electrolysis. So, from the cost point of view, the market deployment scenarios could target any hydrogen market. The Hydrosol technology could take a visible share of this market in the long-term – especially alongside the deployment of Fuel Cell Vehicles–, provided that a pro-active, but yet careful, staged market introduction and deployment process is followed (first a full industrial demonstration, followed by a set of well chosen market introduction cases, paving the way for a later large scale deployment on a wide range of sub-markets).
Potential Impact:
The principal objective of HYDROSOL-3D is the in-detail preparation of a plant for solar thermo-chemical hydrogen production from water in a 1 MW scale on a solar tower. The efficient conversion of solar energy into Hydrogen achieved by the HYDROSOL technology (with virtually zero CO2 emissions), has the potential to provide solutions to long term threats to our society associated with energy supply, environmental pollution and climate change by making possible the large-scale, efficient production of pure Hydrogen, from exclusively renewable resources: sun and water.
The annual implementation plan of the FCH JU stresses the necessity of developing hydrogen production processes from carbon-free sources by 2015 and the need “to demonstrate the technical and economical feasibility of thermo-electrical-chemical decomposition of water as a potential pathway for the renewable production of hydrogen”. HYDROSOL-3D’s main objective is exactly to do this and even beyond: the project delivers not only concepts but also a detailed design including all necessary and appropriately sized components. This is possible because the technology has been already developed in the earlier projects HYDROSOL and HYDROSOL-II up to a stage (100 kW) which is with respect to maturity, size, and layout close to what is expected for a demonstration plant. HYDROSOL-3D will cover the remaining measures necessary to lead the technology to a demonstration and to prepare such plant in detail.
Beyond the compensation of natural fluctuations and depending on plant location and local demand “solar” hydrogen will also be produced directly for the use as fuel for mobile and stationary applications. This development surely will be fostered in the beginning by the forecasted annual increase of hydrogen consumption and demand by 10-20 % in the next years, which is mainly due to the increasing demand for fertilizers and for the exploitation and upgrading of harder accessible fossil resources. The modularity of HYDROSOL technology allows easy replication. In addition it represents a value-added proposition to all concentrated solar thermal tower installations, as it only requires a marginal cost while at the same time achieving chemical storage of the solar energy and in this way it resolves the supply-demand temporal mismatch of solar technologies. HYDROSOL technology has the flexibility of application in many areas of Southern Europe and many other parts of the world such as the countries of northern Africa, the Persian Gulf, the Arabic and Indian peninsulas as well as the American and Australian Continents which have sufficient insolation for installation of solar tower plants (>1800 kWh per square meter per year of direct normal solar radiation) and proximity to water (inland or at the sea). The construction of solar hydrogen facilities in such areas will create a number of new industries for the fabrication of components assembling and operation maintenance. The technology required for manufacturing HYDROSOL plants can be implemented locally, and this will give the opportunity to create links with developing countries and their markets, leading to even greater replication potential. The HYDROSOL technology aims thus to be the first demonstration of solar chemistry-based hydrogen production from water, with a future potential - when employed in combination with concentrated solar thermal power plants - to achieve a hydrogen cost competitive to that of non-sustainable, CO2-emitting, hydrogen production. Exploiting these benefits will in turn translate into socio-economic profits such as independence from fossil fuels, improvement of living standards, health and safety and increase of industrial growth. The latter will have significant potential for job creation and employment: construction of plants, plant operation, solar equipment fabrication, chemical reactor equipment manufacturing, water-splitting material production.
List of Websites:
www.hydrosol3d.org
Coordinator: Athanasios G. Konstandopoulos
CENTER FOR RESEARCH AND TECHNOLOGY HELLAS
6th km Charilaou-Thermi rd, 57001 Thessaloniki, Greece
E-mail: agk@cperi.certh.gr
tel: +30 2310 498 192