Facilities operations and maintenance encompasses all that broad spectrum of services required to assure the built environment will perform the functions for which a facility was designed and constructed.
Operations and maintenance typically includes the day-to-day activities necessary for the building and its systems and equipment to perform their intended function, meaning: employees salaries, insurances, etc.
The operation an maintenance cost depends on the installed power of the facility, that is why it is expressed in CHF/kW. It is independent to the number of hours that the facility has been run.