Emission-Free Hydrogen Production from Solar Energy: HZB’s Direct Approach
Here’s an article posted in PV Magazine.
According to the article,
- Traditional production takes the “indirect” approach using solar and wind to power electrolyzers with round-trip efficiencies of around 30%.
- A research team at the Helmholtz-Zentrum Berlin (HZB) Institute for Solar Fuels is investigating the “direct” approach to emissions-free hydrogen production.
- They are developing photoelectrodes that convert sunlight into electrical energy and are stable in aqueous solutions.
Additional details about the post:
Green hydrogen production refers to the generation of hydrogen fuels using emission-free sources such as solar and wind energy. While renewables-powered battery technology is expected to dominate the energy transition, green hydrogen is particularly attractive for heavy trucking and industrial applications due to its ability to deliver high power outputs.
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There are two main approaches to green hydrogen production: the indirect method, which utilizes solar and wind energy to power electrolyzers, and the direct method, which involves converting sunlight directly into electrical energy to split water into hydrogen through a process called photoelectrochemical (PEC) water splitting.
The indirect approach has achieved round-trip efficiencies of around 30%, while the direct approach, using PEC cells, has efficiencies near 10%. Despite being less efficient, PEC cells offer advantages such as the ability to utilize sunlight heat to accelerate reactions and the potential for using more abundant and inexpensive catalyst materials.
However, despite these advantages, PEC technology is not yet competitive with the conventional electrolysis method in terms of cost and energy efficiency. Hydrogen fuel from PEC systems currently costs about $10 per kg, significantly higher than the $1.50 per kg cost of hydrogen produced from fossil methane steam reforming. Additionally, the energy demand for PEC water splitting is estimated to be four to 20 times higher than for electrolysis-based green hydrogen production.
To address these challenges, researchers at the Helmholtz-Zentrum Berlin (HZB) Institute for Solar Fuels are exploring additional benefits of PEC technology. One such benefit is the potential to produce methyl succinic acid (MSA) alongside hydrogen by reacting hydrogen with itaconic acid in the same reactor.
The energy payback period for producing hydrogen alone using PEC technology is estimated to be about 17 years with a modest 5% solar-to-hydrogen efficiency. However, if a portion of the hydrogen produced is used to convert itaconic acid into MSA, the energy payback time can be halved. With 30% of the hydrogen converted into MSA, the production energy can be regained after just 2 years.
This approach significantly reduces the production cost of green hydrogen and increases the economic feasibility of PEC technology. The next step for the research team is to test the simultaneous production of hydrogen and MSA in the laboratory to validate its practical viability.
Interestingly, we have some other posts related to this content:
- Green Hydrogen Production Boosts by Solar Device: Hits 20% Efficiency
- A new solar-radiation-concentrating device has surpassed 20% efficiency in hydrogen production, generating green hydrogen at over 2 kilowatts and usable heat at 70°C, potentially applicable in hospitals, electric vehicles, and residential heating.
- Hydrogen-Producing Rooftop Solar Panels: The Future of Clean Energy
- Researchers at KU Leuven have developed hydrogen-producing rooftop solar panels nearing commercialization. These panels are compatible with common PV structures and utilize non-precious materials to keep costs low, indicating readiness for industrial production.
- AI Solar Tech For Green Hydrogen – Lancaster and Heliogen
- Lancaster has partnered with Heliogen to employ AI solar technology for green hydrogen production, aiming to power the city’s fleet with AI-enabled solar energy technology.
- Southeast Asia’s First Solar-Hydrogen 5G Tower by Solarvest-Huawei-CENTEXS
- Southeast Asia’s first 5G tower, powered by a solar-hydrogen microgrid testbed system, has been built by Solarvest, Huawei, and CENTEXS in Sarawak, aiming to advance the clean energy industry in Borneo.
- Solar-Powered Hydrogen Generation from Seawater: by IIT Madras
- IIT Madras researchers have developed a solar-powered system to generate hydrogen from seawater, producing 100 liters per day, enough to power a small car for 100 km, using solar energy, seawater, and a catalyst.
