When deciding on a generation scheme or schemes it is vital to ensure the cost effectiveness of the installation.

If you have poor power quality you may need to install larger equipment which is a waste.

Example: A plant wants to install a diesel generator as a backup unit. A simple logging of load indicates a unit of 1.2MW is required plant is installed and it is noticed on the generator controller it seems to be an average 800kW

which is about 66.6% which is generally considered not as efficient as probably could be as 80% is considered to be optimum load. 

Come the day and a major revamp happens and a lighting upgrade together with the installation of several VFD's has occured and at the same time energy efficiency was conducted at commissioning to ensure best process control.

Unbeknownst to plant owners the load on the generator is now averaging around 650kW around 54% which is now even lower then original load now the plant only operates 4 days a week so on the "off" days it can be as low as 25% which is now entering the  "glazing" territory and burning more fuel than in comparison to 66.6% and 54%.

Now as the plant owner you now have an over sized plant, so apart from capital cost and now transpires into higher maintenance and operation costs. If the plant had been the "all singing and dancing installation" then a smaller unit could have been purchased and the difference of money could have been placed into more automation, alrams, and monitoring systems.