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Thermochemical Hydrogen Production from Concentrated Sunlight


Proposals should focus on improving performances and looking for compatible target costs of the final technology Improving performance and reduce cost of thermochemical hydrogen production from concentrated sunlight. New solutions of components and overall system should be validated in the field.
The project proposal should address the following elements:

  • Improve the stability, cyclability and performance of functional materials for high temperature water splitting; in many cases a suitably tailored microstructural design of reactor materials shows promise to overcome some of the challenges; these suitable materials need to exhibit sufficient stability and activity over at least 1000 cycles or 5000 hours of operation;
  • Design novel solutions for high temperature solid-solid and solid-gas heat recovery. This is of utmost importance to achieve highly efficient processes. Ca. 5 % are reported as the highest solar to fuel efficiencies of state of the art processes. To get closer to competitiveness such value needs to be doubled. Heat recovery rates substantially higher than 50 % are requested to meet that target;
  • Design of highly efficient solar interfaces and reactors. High efficiencies are often bound to high reaction rates achievable through smart material solutions and fluids handling;
  • Provide suitable and robust materials and design solutions for plant components with high thermal loads. The temperatures of the key components are very high. To provide such components ensuring lifetimes of more than 10.000 hours is crucial. Demonstration of long-term performance of materials and key components under realistic boundary conditions using existing solar test facilities is needed. A representative and meaningful demonstration will be possible with core components like the solar receiver in a scale of about 500 kW. The testing period of the hardware should be of a relevant and representative duration, for a period of minimum 6 months;
  • Design and development of intelligent systems and a smart process of control and automation, including predictive and self-learning tools;
  • Embed and validate smart solutions to minimize the consumption of auxiliaries like flushing gas. Target should be to reduce energy losses through such auxiliaries to less than 25 % of the energy output;
  • Comparative potential benchmarked analyses assessing the technical and economic viability prospects of the technology towards benchmark other processes needs to be refined based on state-of-the-art materials, components and processes;

TRL at start: 3 and TRL at end: 5.
The proposal should build on previous FCH 2 JU projects' results on related processes and should seek intensive cooperation with European and national projects dealing with thermochemical fuel production; cooperation with Mission Innovation challenge 5 (‘Converting Sunlight’) [20] is encouraged.
Any safety-related event that may occur during execution of the project shall be reported to the European Commission's Joint Research Centre (JRC) dedicated mailbox, which manages the European hydrogen safety reference database, HIAD.
Test activities should collaborate and use the protocols developed by the JRC Harmonisation Roadmap (see section 3.2.B ""Collaboration with JRC – Rolling Plan 2018""), in order to benchmark performance of components and allow for comparison across different projects.

Footnote [20]:

The FCH 2 JU considers that proposals requesting a contribution of EUR 3 million would allow this specific challenge to be addressed appropriately. Nonetheless, this does not preclude submission and selection of proposals requesting other amounts.
Expected duration: 3 - 4 years.

Carbon-free hydrogen production from water decomposition pathways powered by solar energy is a major part of the long-term R&D strategy of the FCH 2 JU for sustainable hydrogen supply. Thermochemical processes require less energy conversion steps for hydrogen production by renewable energy compared to electrochemical processes. Therefore, they have the potential to be more efficient.
Solar thermo-chemical cycles are capable to directly transfer concentrated sunlight into chemical energy by a series of chemical reactions. Based on concentrated solar radiation technologies the processes can be scaled-up to very large scale exceeding 100 MWth. Recent solar thermochemical research has focused on metal oxide based and sulphur based thermochemical cycles since they have the highest potential to be competitive, practicable and scalable up to an industrial level.
The success of those processes is often strongly linked to the availability of materials and components with the required properties. The performance of the current materials, mainly redox materials and catalysts is limiting the production rate of hydrogen in a concentrated solar power reactor. Sufficient heat can be introduced in the solar reactor. However, the mass transfer to the reactive surface, the heat transfer to and between the reactants and the chemical conversion rate of steam to hydrogen is limited by the properties and structure of the adsorbent materials currently available. Therefore, smart technical solutions are needed for material properties and structures on the one hand and for solar interfaces, reactor designs and for fluids consumption and handling on the other hand. Highly efficient components of the solar receiver/reactor unit as well as of the heat recovery unit are essential to achieve the required overall process efficiencies.

The project is expected to advance the knowledge and prove the technological feasibility of the concept of solar thermochemical water splitting including the environmental, social and economic benefits. The proposal should show its contribution towards building a sustainable renewable energy system contributing to the decarbonisation of our economies. The proposed solutions are expected to contribute to strengthening the EU leadership on renewables. In the case of solar-thermochemical water splitting this will be achieved through proving the feasibility and performance of key materials and key components needed to carry out the process in relevant scale.
The consortium will ensure that following actions are included in the project to fulfil to the planned target and reach the KPIs, such as:

  • The process should be demonstrated at realistic scale and working conditions, ideally using an existing solar demonstration facility (>2 hundred-kW range);
  • The process and plant behaviour should be validated through medium to long-term operation;
  • Finalization of a design and development of a technology with annual solar-to-fuel efficiencies in the range efficiency of 10 % (ratio of solar radiation entering the plant to calorific value of the fuel exiting the plant), doubling the state-of-the-art efficiency for processes with about 5 %;
  • Demonstration of at least 5 % efficiency in the field tests;
  • Achieving of heat recovery rates of high temperature heat in excess of 60 %;
  • Achieving a process strategy allowing full automation.

These are needed to establish solar thermochemical water splitting as a completive technology for suitable sites and to contribute to achieve economic competitiveness to hydrogen production through PV or CSP powered electrolysis.
The project results should contribute to an increased decarbonisation of the transport sector, to a reduced dependency on fossil fuels and to a reduction of emission of air pollutants. The project should create significant visibility to the potential of applying solar thermal energy for fuel and in particular hydrogen production.
Type of action: Research and Innovation Action
The conditions related to this topic are provided in the chapter 3.3 and in the General Annexes to the Horizon 2020 Work Programme 2018– 2020 which apply mutatis mutandis.