CIRCLE WITH A DOT

@blinry but then almost everyone has a power bank so people are probably helping each other out.

@blinry the power banks are necessary because you do so much on a phone. Imagine being far away from home with 5% battery. You will not be able to take a metro, call a cab or maybe not even know how to get home on foot without a phone.

@samueljohnson @gahms @randahl in case of PV the limit was technology. In case of green hydrogen the limit is physics. We can make the technology better and cheaper but we are stuck with the current physics.

@samueljohnson @gahms @randahl It does not exist in a practical scale because it is extremely expensive. I have not seen any hydrogen only A330-class transatlantic flight yet. Only small scale tests on auxiliary systems. Can you post the source?

There are other possible avenues for sustainable aviation fuels but nothing is close to a possible implementation stage.