What do you expect from idiot hipsters incapable of basic math and science, and who generally have no idea what the hell they're talking about, just building stuff well enough to take a few pictures?

Some quotes:

"Off-grid solar PV systems often charge lead-acid batteries."

Nobody is using lead-acid anymore, which shows how out of touch these idiots are with reality. For 5, if not 10 years LiFePO4 batteries have been the best option even for DIY systems.

You lose half the power you put into them, the deeper you discharge them the more you wear them out which means you have to buy far more capacity than you need, whereas LiFePO4 you can discharge down to 10% and charge to 90% and still get thousands of cycles out of them before they degrade to maybe 80% of their nameplate capacity. You also get higher working voltage - 13-13.8v for much of the battery's state of charge. I'm not kidding when I say that from efficiency losses alone you DOUBLE your effective solar generation by switching to LiFePO4 from lead-acid.

"At the other extreme, resistance on the pedals is too high when powering a kettle or a refrigerator."

It would take three hours for the average person to put enough energy into a "perfect" kettle to get it to boil, using a "perfect" bike that could convert the roughly 100W of mechanical effort into 100W of heat in the kettle....

Between mechanical and electrical losses, heat loss in the kettle, and energy inefficiency of the human body, I would rule it nearly impossible for even some of the world's most elite cyclists to power an electric kettle long enough for it to boil.

The handcart article goes to explain at length why a multitude of other options are inferior, but then they act like an electric generator bike would provide any sort of meaningful amount of power compared to just putting a solar panel outside.

Especially if you're willing to buy used, solar is dirt cheap. You can get NEW panels 300-400W panels on clearance for ~$100. You can get a nice-but-cheap 1-1.3kWh 12v battery for about $250. A top-notch solar controller, $75-100. And that battery will fully charge from dead in one day worth of sun in non-ideal conditions...

Commercially Available Bike Generators Are Not Sustainable (2011)