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I have two questions.

1. How efficient is this process, i.e. how much ethanol does your lab setup produce per litre of reactor volume and hour?

2. Is the need of hydrogen a problem, i.e. is the required amount of hydrogen for real world usage at scale easily available or would this require significant additional hydrogen production capacity?

EDIT: Number two has mostly been answered in another comment.

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Process efficiency can be measured in different ways. I can't give you a number on energy efficiency yet but what I can say is that the carbon efficiency of the process can get close to 100% yield. We aren't there yet for a number of reasons, but to provide details, two things it is related to are mass transfer (how much of the gas is dissolved into the water) and the residence time (how long the gases are in the bioreactor). With our current setup, neither of these has been optimised so the yield isn't great. But this is part of developing the process. We will soon be switching to better bioreactor designs to improve on these fronts.

Your other comment relates to productivity and can be expressed as space time yield (STY). Like the above we need to improve on this and is part of our next steps.

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