SunHydrogen Inc (HYSR)

[PJM1984]

Be careful not to read too much into this figure.

From the looks of it, its just a traditional solar concentrator device with possibly an efficient traditional mult junction pv cell which powers a traditional electrolyzer.

We also don't know what benchmark tests were used to determine 22% efficiency.

Also, electrolyzers typically need pure water. The costs of the system are also unknown and it probably can't, by its nature, produce any value added byproducts without additional subsystems which will increase costs and lower efficiencies.

Take a >30% efficient pv cell and a ~75% efficient electrolyzer, tweak selection to account for other system efficiencies and your benchmark test requirements and you get 22%, its doable, but is it economical? Are they just trying to get media attention?


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http://pubs.rsc.org/en/Content/ArticleLanding/2015/EE/C5EE02214B

There is intense interest in the solar driven conversion of water to hydrogen as a means of achieving the sustainable generation of a practical fuel. It is widely considered that such “Artificial Photosynthesis” processes need to achieve an energy conversion efficiency exceeding 10% to have practical impact. Although some solar-driven fuel generating systems have reached efficiencies as high as 18%, they are often based on precious metal catalysts, or offer only limited stability. We describe here a system that utilises concentrated solar power, which is inexpensive to produce, and an electrolyser module based on Earth-abundant materials capable of operating under benign conditions. This system delivers the highest efficiency reported to date, in excess of 22%. The electrolyser functions in electrolytes with pH values ranging from neutral to alkaline, including river water, allowing implementation in a variety of geographic locations. Testing over multiple diurnal cycles confirmed the long-term stability of performance. We also describe an analysis of the efficiency in terms of the critical cell-matching parameters and thereby understand the key directions for further optimisation. This simple and adaptable system addresses key criteria for the large-scale deployment of an artificial photosynthesis device.

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just my opinion

PJM