However, I think your guess of the efficiency of a gasoline powered engine is too high. I would expect it would be closer to 5% efficiency.

So you were 5 times too harsh on your electric bike when looking at the gas efficiency (to calculate total Joules) but you were 6 times too generous when getting the amount of energy under the Earth’s atmosphere at mid latitudes. Based on my guestimates, I think you are a tad generous on only a 19.5 hour recharge time.

An electric battery has multiple cells, so the electric storage in cars or in your smoke detectors are ‘batteries’ but the 1.5V ones in your MP3 player are just ‘cells’. Of course, this usage is largely obsolete and ‘battery’ is used for all of them.

Presumably the people who talk about ’solar batteries’ are emphasizing that you have a bunch of these things in series to get a higher voltage than you could get from a single solar ‘cell’.

The very first law to be legislated is that all roads must be downhill to all destinations. The second law to be legislated is that all roads must be cycloids. That way everybody gets to their destination with the same elapsed time no matter where they start. No discriminaton! Zero carbon footprint, too.