Hydrogen Solar technologies produce hydrogen directly and independent of fluctuating energy and feed-stock costs. This is 'green hydrogen' as contrasted with 'black hydrogen', derived from fossil fuels and nuclear energy which arrive with hidden costs.
The Tandem Cell is the only technology approach that targets both the capital cost and the high electricity cost of electrolysis. In the photo-electro-chemical process, only solar energy is used to split water into its constituent parts; no other energy input is required in the process, and the hydrogen produced is currently analysed at 99.99% pure.
Additionally, there is no by-product as a result of the direct solar electrolysis, only hydrogen and oxygen. Currently 95% of all hydrogen is produced using steam methane reforming which generates up to 6 times as much carbon dioxide as it does Hydrogen. This carbon must be sequestered to prevent further risk to the atmosphere. Current projects take CO2, liquefy it and pump it back into disused oil wells where it is hoped it will remain. This process is reported to reduce overall plant CO2 emissions by 85 to 95%.