You certainly don't need free electricity. Even if electricity is relatively expensive in your area (as it is in China) the amount of electricity needed for run

You certainly don't need free electricity. Even if electricity is relatively expensive in your area (as it is in China) the amount of electricity needed for running an electric bike (as compared to the operating costs for a car) is trivial. What you do need are good rechargeable batteries - and those batteries will eventually need to be replaced.