Clean Hydrogen production: CO2-emission-free alternatives
David Serrano;
CIEMAT Contact: Rocio.Fernandez;
Cooperative Project funded by the 4th PRICIT-Madrid Regional Plan for Science and Technology. Total budget: 1000 k€. CIEMAT Budget, not including personnel: 240 k€.
January 1, 2006 – December 31, 2011

The motivation for this project was basically to coordinate the research efforts and capabilities of research groups in Madrid (URJC, CSIC, CIEMAT and INTA) in clean hydrogen production, that is, CO2 emission free and using renewable energies ad the primary energy source for its generation. Two Companies in the power industry (REPSOL YPF and HYNERGREEN) are also involved in the project and have shown their interest in actively participating in the project and following up on the results.


The general purpose of this project is to study the various clean hydrogen production processes in order to progress in the solution of technological and economic limitations it currently presents and that are essential to a future transition to the hydrogen economy. The alternatives under consideration In this project are characterized by avoiding the formation of CO2 as a co-product of hydrogen and use of renewable resources to provide the energy consumed in the formation and release of hydrogen.

The hydrogen production processes under study in this project are the following: photo-electrolysis of water, thermochemical cycles and de-carbonization of natural gas. This project intends to evaluate the mid-to long term technological and economic feasibility as well as their ability to reduce CO2 emissions over more conventional hydrogen production systems, such as gasification and steam reforming.


In 2010, the solar facility was mounted to conclude the commercial ferrite evaluation task. Along with the GIQA-URJC Group, the solar fluidized bed reactor design was completed. For this, the GIQA-URJC Group carried out fluidization experiments in the lab with the ferrite selected for the first solar tests (NiFe2O4 Sigma-Aldrich), and were able to fluidize particles of 125 to 250 μm, as the smallest size possible, at 900ºC. Based on the laboratory fluidization conditions, reactor dimensions were scaled up to connect it to the solar concentrating system installed in the CIEMAT-Madrid.

The concentrating device has a 6-m2 reflective surface and can reach a solar concentration of 500X, having measured 2 kW in a diameter of 20 cm.

The reaction system is complete with gas (N2) supply mass flow control, a water injection pump for the hydrolysis stage, a ceramic heating element for preheating gas, a water condensation system and a gas chromatograph (μ- GC) .

Photo of the facility and control schematic

Fluidization tests and their evaluation for finding out whether the system is adapted to process requirements will be made very soon.

Universidad Rey Juan Carlos, CSIC, INTA, REPSOL, HYNERGREEN y CIEMAT