I guess integration with Google Drive is a big convenience for users.
But yes, if the cost of getting access is to high for indie developers, then it make sense to avoid Google Drive. Creating and maintaining your own cloud sync service for a specific app may not be worth it, they should investigate integration with existing Google Drive competitors/alternatives.
Friction is how classic braking work, and all the energy that goes into friction is lost. Regenerative braking typically rely on magnets and rotors to slow a train. When a train brake, it uses part of its kinetic energy to spin a rotor, which generate electricity using spinning magnets.
The article is otherwise interesting, it’s just unfortunate they got the basic physics wrong.
Reference: Review and trends in regenerative braking energy recovery for traction power system with inverter substation in subway’s of São Paulo city