Your questions on green hydrogen and electrolysers answered!
I visited Green Hydrogen Systems in Kolding, Denmark to ask an expert all about electrolysis and electrolysers.
01:11 How does an electrolyser work? (tabletop electrolysis demonstration)
01:49 What are the components in an electrolyser?
02:30 What consumables does the process use?
03:17 How can we make electrolysis more efficient?
04:25 What are the advantages of alkaline water electrolysis compared to PEM (polymer electrolyte membrane) or SOEC (solid oxide electrolyser cell)?
05:09 How much does an electrolyser cost? (levelized cost of hydrogen, capex, efficiency)
06:07 What do you do with the oxygen after you split water?
06:39 Electrolyser tour: an up-close look at a real electrolyser
08:06 Do you have to use pure water for electrolysis, or can polluted or salt water be used?
08:46 How much hydrogen can a shipping container sized electrolyser produce?
09:02 Applications for hydrogen: will we use hydrogen to store and generate electricity?
09:46 What about the low efficiency of using electricity to make hydrogen instead of just using electricity directly?
11:01 How do you calculate the efficiency of an electrolyser? (electrolysis thermoneutral voltage)
12:06 How much more efficient can electrolysis get?
12:26 What kinds of improvements are needed to improve efficiency?
12:59 How long will it take to develop a more efficient electrolyser?
13:16 Is it realistic that the price of hydrogen can come down as quickly as it is predicted to?
“There’s a natural hierarchy somehow, you should use electricity as electricity for all the cases you can. Of course, that’s obvious. But when you cannot use electricity, you need to convert it to something else. And then hydrogen is a very good candidate.”
This was the answer from Kasper Therkildsen, Head of Technology at Green Hydrogen Systems, during our recent tour/ interview when I questioned the low efficiency of using electricity to make hydrogen relative to just using electricity directly.
We discussed likely applications for hydrogen (Kasper anticipates transportation, industrial purposes and in some cases process heating), and we ran through as many as time allowed of the fifty viewer questions you all suggested ahead of the tour.
There’s a benchtop demonstration of alkaline water electrolysis, we talk electrolyser technology development, how much more efficient it can get (and how, and how quickly).
But is it realistic that the price of hydrogen can come down as fast as it is predicted to? According to Kasper:
“10 years back nobody believed that the price of electricity would be where it is now from renewable sources. And we’ll see the same with hydrogen. You know, once things get rolling, it’s gonna be tremendous.”
Thanks to Kasper Therkildsen and the rest of the team at Green Hydrogen Systems for spending an afternoon with me and patiently answering all of my questions!