The world needs a new source of energy, an unspillable source.

How to generate electricity from powered sewing machine, whose motor runs around 2000 rpm?

We’ve 500 powered sewing machines in our factory. Like all the machines running by motor these, sewing machines are also working. My idea is to use motor’s rotation to generate electricity, like wind mill and turbines work. Conversion of elxtrical energy to electricity. Can someone help me how to execute this in most economical way…