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Solar Panel Splits Water To Produce Hydrogen (ieee.org)
schwit1 shares a report from IEEE Spectrum: A team at Katholieke Universiteit Leuven, or KU Leuven, says it has developed a solar panel that converts sunlight directly into hydrogen using moisture in the air. The prototype takes the water vapor and splits it into hydrogen and oxygen molecules. If it scales successfully, the technology could help address a major challenge facing the hydrogen economy. A small but growing number of facilities are producing "green" hydrogen using electrolysis, which splits water molecules using electricity -- ideally from renewable sources such as wind and solar. Other researchers, including the team in Belgium, are developing what's called direct solar water-splitting technologies. These use chemical and biological components to split water directly on the solar panel, forgoing the need for large, expensive electrolysis plants.
KU Leuven sits on a grassy campus in Flanders, the Dutch-speaking northern region of Belgium. Earlier this month, professor Johan Martens and his team at the Center for Surface Chemistry and Catalysis announced their prototype could produce 250 liters of hydrogen per day on average over a full year, which they claim is a world record. A family living in a well-insulated Belgian house could use about 20 of these panels to meet their power and heating needs during an entire year, they predict. The solar panel measures 1.65 meters long -- roughly the height of a kitchen refrigerator, or this reporter -- and has a rated power output of about 210 watts. The system can convert 15 percent of the solar energy it receives into hydrogen, the team says. That's a significant leap from 0.1 percent efficiency they first achieved 10 years ago.
KU Leuven sits on a grassy campus in Flanders, the Dutch-speaking northern region of Belgium. Earlier this month, professor Johan Martens and his team at the Center for Surface Chemistry and Catalysis announced their prototype could produce 250 liters of hydrogen per day on average over a full year, which they claim is a world record. A family living in a well-insulated Belgian house could use about 20 of these panels to meet their power and heating needs during an entire year, they predict. The solar panel measures 1.65 meters long -- roughly the height of a kitchen refrigerator, or this reporter -- and has a rated power output of about 210 watts. The system can convert 15 percent of the solar energy it receives into hydrogen, the team says. That's a significant leap from 0.1 percent efficiency they first achieved 10 years ago.
The average Northern European home can't fit 20 of these panels on its roof. Unlike PV solar panels, these things have an added benefit: the hydrogen can be stored for later use without the need for expensive batteries... but you will likely need to compress the hydrogen which requires a fair bit of energy. Do they foresee these panels being used in residential installations, or are they more suited for solar farms?
Regardless, it's an interesting development. Good advances in hydrogen storage and transport have been made, and there's already a few hydrogen cars on our roads, but the production of green hydrogen (i.e. not produced from natural gas) has been expensive and troublesome thus far. Though the secrecy surrounding this project is generally a red flag for inflated expectations.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Huh?
Hydrogen can be used to generate electricity. So it can be used for storing solar energy and then used during the nights.
Also some cars and busses are using hydrogen as their power source.
This is what the Martians did. They became a full hydrogen economy. They converted a lot of their planet's water into hydrogen and it escaped into space! They didn't have enough fresh water left to sustain their economies. The resulting wars left lots of craters.
And their atmosphere got so thin without moisture that it was blown away by the solar winds. Over thousands of years, the solar radiation and planetary dust storms degraded everything and turned it all to dust.
210 Watts peak * 15% efficiency
WP already includes the efficiency figure, it's the maximum power put out by the panel under ideal conditions. At peak production, 210 W will go into hydrogen production.
If construction was anything like programming, an incorrectly fitted lock would bring down the entire building...
Currently, from an energy ROI POV, hydrogen as a fuel is just about useless; it can either be produced from fossil fuels, which is exactly what we do not want, or we can make it through electrolysis, but this approach is wildly inefficient compared to just using the electricity directly, like we do now.
Just about the only chance to make hydrogen as a fuel worthwhile (compared to electricity production) is if we can use availably energy _directly_ for electrolysis or thermal decomposition in a way that's more efficient than making electricity. Since PV panels are wildly inefficient (albeit significantly more efficient than photosynthesis), a solution like this might turn out to be a game changer, making a hydrogen economy feasible instead of a subsidy-fueled wildly inefficient pipe-dream.
Also, for production of rocket fuel on other planets or the moon, this thing might be turn out to be big.
0x or or snor perron?!
The panel uses
catalysts, membranes, and adsorbents
Those sound a lot like consumables to me. That's the question with any "breakthrough" of this sort is just how much stuff does it consume and how much does that stuff end up costing (in energy, carbon emissions and pollution as well as monetarily).
Solar panels are pretty dang amazing as they are static and essentially last forever (or at least for multiple decades), unlike pretty much every other form of energy generation we know of. So by associating the hydrogen generation with solar panels they are asserting that kind of longevity and hands-off operation.
Better known as 318230.
Huh? The "exhaust" from burning hydrogen is water.Â
Are you crazy? Dihydrogen mono-oxide has killed millions of people.
The problem with making steam or splitting water is the minerals and gunk in the water eventually foul the solar panels. This is why, fo example, a recent innovation in non-contact low emissivity steam generators is a big deal. It's not that they improved the low emissivity desgin it's that they came up with a way to heat the water radiatively without it touching the expensive and hot parts.
Second if you are going to use electrcity to split water then, since solar panel electricity generation is ineffieinet you are better off using the solar power to pre-heat the water with waste heat ( this makes it significantly easier to split since you are paying a down payment on the free energy needed to go from liquid to gas phase).
If you first make electricity to split it then making sure the electrical generation part doesn't touch the water itself is needed.
Some drink at the fountain of knowledge. Others just gargle.
True. But, at a 15% lab efficiency level, it is much less efficient at producing hydrogen than current solar to electric technologies. Furthermore, the compression/storage/fuel cell/inverter storage system required to utilize the hydrogen is far less efficient and more expensive than the charger/battery/inverter based storage system required to utilize the output of solar electric cells.
Higher efficiencies can be achieved with fuel cells if you also collect and use the waste heat, but that requires even more changes to the home. And, we could increase the systemic efficiency of batteries and inverters in the same way (collect the waste heat and use it for something like boosting the water heater efficiency), but have not found the cost worth it given how high the system efficiency already is.
In short, this would seem to need much more efficiency throughout the system, not only at production, before beating existing renewable technologies even for utility use. It is even further away from enabling transition to a more reliable fully distributed energy industry. Of course, that is why they continue to look at it. They are desperate to maintain the centralized energy production model.