Specifying Typical Output Data
Under certain circumstances, it is useful and necessary to specify data that are usually Output data. Typical Input data, which are normally given, can be calculated on the other hand.
Removing Write Protection for the Output Data
In the normal application of TOP-Energy, it is not possible to process the output data. If you still want to edit Output data and have the necessary expert knowledge, click on the button 
Edit output data in the Home ribbon in the Forms group. Then the lock symbol opens 
, and you can edit the output data. By clicking on the lock symbol again, the lock closes and the write protection is restored.
Using the following energy system, two application examples illustrate how you can sensibly specify Output data.
Specifying Your Own Operating Mode
In the energy system shown above, a heat demand must be covered. Two producers are available for this purpose: the district heating supplier and the CHP unit. This gives the system a degree of freedom. This degree of freedom is normally eliminated during the simulation by determining the most favourable way (economically or ecologically depending on the target function) to operate the energy system. In some cases, however, the mode of operation of the district heating supplier and the CHP unit should not be optimized but specified, e.g., if the system is not controlled or a certain mode of operation of past periods is to be simulated.
To specify the operating mode of a CHP unit that is not to be operated variably, enter the Supplied heat in the Output data of the component form, in our example 45 kW (see following figure). You can also store this as a time series.
Run the simulation. As a result, the District_Heating_Supplier covers the Heat_Demand to the extent that the CHP cannot cover it with its specified mode of operation.
If the Supplied heat given by the CHP exceeds the Heat Demand, the system cannot be solved without an Emergency Cooler. This shows that extreme caution and expertise are required when editing Output data.
Specifying Volume Flow Instead of Outlet Temperature
Normally the Outlet temperature of the heat conducting medium is specified. With this convention the system of equations of enthalpy and mass flows and associated temperatures is solved. If the convention is observed, the inlet temperatures and mass flows are always calculated. However, it can happen that, for example, only the volume flow of a heat demand is known and is to be used as the input value. In this case, the system of equations can be manipulated so that the outlet temperature is calculated instead of the mass flow. The specification of both values would overdetermine the system. Most likely, no valid solution would then be found.
If the Volume flow of the heat transfer medium (in the Output data form) is to be specified and the Outlet temperature (in the Input data form) is to be calculated, set the Outlet temperature parameter to Calculated value in the Input data form of the Heat Demand component. To do this, right-click on the Outlet temperature identifier and select Calculated value from the context menu (see following figure).
Then a checkmark appears in front of Calculated value in the context menu. The value to be calculated is displayed in blue (see following figure).
In the Output data form, enter the Volume flow rate, in our example 2,000 l/h (see following figure).
Run the simulation.
After completion of the simulation, the calculated value is displayed in blue in the Input data form, in the example 59.774 °C (see following figure).
