The greatest advantage of fluctuating power plants is their
use of energy sources that are free of charge. If the investment
256 Fabian Keller et al. / Procedia CIRP 48 ( 2016 ) 254 – 258
and the maintenance expenses are neglected, there are no usebased
energy generation costs. This fact should also be
included in the production planning and control system.
Figure 2 provides a summary of both power plant
categories.