This is neat. This may not be The Most Practical Solution, but the idea of having a thing that you can carry around and turn local bikes into power generation seems like a perfectly-reasonable invention for me.
We're talking about helping the homeless. They don't need the minmaxxed optimal solution. Not every homeless person may have access to a power outlet-- I don't know who wouldn't be able to move enough to pedal a bike but not enough to get to a public library, but that's really /not the point/. There are a lot of reasons that people end up homeless, and they can cause some really spotty/unreliable behavior.
There's nothing wrong with adding ideas/solutions to the mix. There's no need for a concept like this to replace other solutions. We can use all the viable solutions at the same time.