This supplement contains guideline values for the calculated useful life as well as for the maintenance and price increase rates of system parts. The following sources were used for the numerical values given in this supplement: (1) Useful life: VDI 2067 Sheet 1 From an observation period of 20 years, a useful life beyond that is hardly relevant, as the remaining residual value has little influence on the result. (2) Maintenance rate: VDI 2067 Sheet 1 (3) Price increase rates of system components: Statis ical data from the economic research institute
ONORM M 7140 Beib.5-1999 history
1999ONORM M 7140 Beib.5-1999 Economic comparison calculation of energy Systems based on the extended annuity- method - Guiding values for input-data