Bernay Cifuentes

Latin America is starting its energy transition. In Colombia, with its abundant natural resources and fossil fuel reserves, hydrogen (H₂) could play a key role. This contribution analyzes the potential of blue H₂ production in Colombia as a possible driver of the H₂ economy. The study assesses the natural resources available to produce blue H₂ in the context of the recently launched National Hydrogen Roadmap. Results indicate that there is great potential for low-emission blue H₂ production in Colombia using coal as feedstock. Such potential, besides allowing a more sustainable use of non-renewable resources, would pave the way for green H₂ deployment in Colombia. Blue H₂ production from coal could range from 700 to 8000 ktH₂/year by 2050 under conservative and ambitious scenarios, respectively, which could supply up to 1.5% of the global H₂ demand by 2050. However, while feedstock availability is promising for blue H₂ production, carbon dioxide (CO₂) capture capacities and investment costs could limit this potential in Colombia. Indeed, results of this work indicate that capture capacities of 15 to 180 MtCO₂/year (conservative and ambitious scenarios) need to be developed by 2050, and that the required investment for H₂ deployment would be above that initially envisioned by the government. Further studies on carbon capture, utilization and storage capacity, implementation of a clear public policy, and a more detailed hydrogen strategy for the inclusion of blue H₂ in the energy mix are required for establishing a low-emission H₂ economy in the country.

Hydrogen (H₂) has become an important energy vector for mitigating the effects of climate change since it can be obtained from renewable sources and can be fed to fuel cells for producing power. Bioethanol can become a green H₂ source via Ethanol Steam Reforming (ESR) but several variables influence the power production in the fuel cell. Herein, we explored and optimized the main variables that affect this power production. The process includes biomass fermentation, bioethanol purification, H₂ production via ESR, syngas cleaning by a CO-removal reactor, and power production in a high temperature proton exchange membrane fuel cell (HT-PEMFC). Among the explored variables, the steam-to-ethanol molar ratio (S/E) employed in the ESR has the strongest influence on power production, process efficiency, and energy consumption. This effect is followed by other variables such as the inlet ethanol concentration and the ESR temperature. Although the CO-removal reactor did not show a significant effect on power production, it is key to increase the voltage on the fuel cell and consequently the power production. Optimization was carried out by the response surface methodology (RSM) and showed a maximum power of 0.07 kWh kg⁻¹ of bioethanol with an efficiency of 17%, when ESR temperature is 700 °C. These values can be reached from different bioethanol sources as the S/E and CO-removal temperature are changed accordingly with the inlet ethanol concentration. Because there is a linear correlation between S/E and ethanol concentration, it is possible to select a proper S/E and CO-removal temperature to maximize the power generation in the HT-PEMFC via ESR. This study serves as a starting point to diversify the sources for producing H₂ and moving towards a H₂-economy.

The management of Air Conditioning Systems (ACS) in Data Centre (DC) facilities has a significant impact not only on energy consumption but also on the performance and safety of the hardware. The main purpose of this work is to detect design and operational flaws of the ACS of a Tier 2 DC located at Universidad de los Andes (Colombia) with the aid of Computational Fluid Dynamics (CFD) tools. To achieve this objective, in situ measurements of air humidity and temperature were taken to develop and validate a CFD model. In addition to the current operation, two different scenarios were proposed, and their performance was evaluated in terms of the global temperature and relative humidity profiles, cooling efficiency with respect to the current operation, and air flow currents. The first scenario contemplated the operation of both AC units at full capacity for a normal 24-hour shift, and the second scenario contemplated an unsteady analysis of the AC’s operation on 12-hour shifts. The CFD and experimental results suggest that the DC’s layout and corridor arrangement have several flaws that cannot be overcome with the current ACS. Moreover, the CFD analysis carried out provides relevant insights into the performance of the operational setups tested.

A catalytic screening was performed to determine the effect of the support on the performance of an Au–Cu based system for the removal of CO from an actual syngas. First, a syngas was obtained from reforming of ethanol. Then, the reformer outlet was connected to a second reactor, where Au–Cu catalysts supported on several single and dual metal oxides (i.e., CeO₂, SiO₂, ZrO₂, Al₂O₃, La₂O₃, Fe₂O₃, CeO₂-SiO₂, CeO₂-ZrO₂, and CeO₂-Al₂O₃) were evaluated. AuCu/CeO₂ was the most active catalyst due to an elevated oxygen mobility over the surface, promoting CO₂ formation from adsorption of C–O* and OH⁻ intermediates on Au⁰ and CuO species. However, its lower capacity to release the surface oxygen contributes to the generation of stable carbon deposits, which lead to its rapid deactivation. On the other hand, AuCu/CeO₂-SiO₂ was more stable due to its high surface area and lower formation of formate and carbonate intermediates, mitigating carbon deposits. Therefore, use of dual supports could be a promising strategy to overcome the low stability of AuCu/CeO₂. The results of this research are a contribution to integrated production and purification of H₂ in a compact system.