In the beginning, foot power made things work. Think about women sitting in front of some type of device designed to make something. There would have been a foot pedal to make it spin, twirl or weave. Water then became a source, being used to grind wheat, mash seeds to create oil, or to move logs from one place to another.
Ponies were attached to a tether and walked around and around all day long, day after day, turning a wheel. Eventually coal was used to power huge electricity generating plants. As time passed wind and solar power were incorporated into the grid. Even nuclear power was harnessed.
When you’re creating a setting, you must take into account where your world is on the spectrum of possibilities. If burning wood is the only source, only certain types of machinery are able to operate. If nuclear power is used, a wider range is available.
Your task is to write a scene in which the source of power comes into play. Perhaps it’s just been employed and the characters are terrified, surprised or both. Maybe there’s a breakdown that has the potential to cause catastrophic events to occur. Dialogue and narrative are both critical.
Have fun with this one.