A couple of years ago, there was an electrical issue in an old castle. The work required us to retrofit the lighting in the castle. Despite our efforts to anticipate a certain level of monthly savings and expenditures, we were unable to meet the specified goal (more on this)
Also, during that time, we got a request from a local school board. As it turned out, their motors were failing one of the schools, and no one could identify the reason why. To identify the problem, we left a couple of our analyzers on the school premises for 7 days for monitoring and recording. We found out that when the load dropped in the evening (due to the fact that the school was empty), the utility voltage went off the charts, so much that it damaged the motors.