Map Capacity Loss due to System Aging in TOP-Energy
The nominal peak power (for photovoltaic systems) and the nominal storage capacity (for electricity storage systems) can be reached only at the beginning of the operation of the system, because the degradation increasingly reduces the power or the capacity of such a technical system due to aging. Degradation over several years is not entered directly in the form in TOP-Energy. There are two ways to consider the degradation: the input of a parameter varying in support years in the scenario manager and the input of an average value.
Operational Optimization With the Scenario Manager
The scenario manager maps the progression over several years: the changed values of certain parameters are specified for given support years, and the effects can be viewed after the variant has been executed. You can select all input parameters, not only the economic input data, to map their progression over the support years. The following example shows how the reduction of the peak power of a photovoltaic module is entered in the scenario manager by the Tabular parameter input.
The scenario manager is located in the form of the variant node. Select Tabular input as Type of parameter input from the drop-down list. Add as many support years as necessary using the green 
plus sign. For each support year, 
Append a row to the table and select the Installed peak power (STC) of the Photovoltaic system as the Varying parameter in it. You can also copy the table from one support year and paste paste it in the other support year.
Then enter a New value, which is lower in each case according to the degradation.
Start the execution of the variant with the 
TOP-Energy button. This will calculate all the specified support years.
Averaged Power or Capacity
Degradation can be considered alternatively to the scenario manager by specifying an averaged system peak power or Storage capacity.
For example, for a battery storage for electrical energy (Electricity Storage) with a storage capacity of 100 kWh and a degradation of 5 %/year, calculate the average capacity in ten years using the arithmetic mean:
\begin{equation} \begin{aligned} \text{Capacity}_\text{average} &= \dfrac {100 \ \text{kWh} + 100 \ \text{kWh} \cdot 0{.}9500^9} {2} \end{aligned}\end{equation}
Alternatively, use other mean values.
This procedure is particularly recommended for structural optimization because the structural optimization is based on the technical system parameters of the start year unchanged for the entire period under consideration in order to maintain a reasonable calculation time.\(\)
