The Wachowski’s original idea was using humans as a computational source. The humans as batteries change was to make it more accessible to a general audience.

The Wachowski’s original idea was using humans as a computational source. The humans as batteries change was to make it more accessible to a general audience. Some discussion on stack exchange: https://scifi.stackexchange.com/questions/19817/was-executive-meddling-the-cause-of-humans-as-batteries-in-the-matrix/19819 https://scifi.stackexchange.com/questions/19817/was-executiv...