Electric Consumers
In the component Electric consumers and internal grid, the electrical consumption may be specified by means of suitable consumption profiles. Multiple consumption profiles may be selected and respectively added to a specific time step.
Consumption profiles may be scaled to an annual value. The value “0“ resets the annual consumption to the original profile value.
If no electrical consumption is available, the number of consumption profiles may be set to “0”.
In Polysun, profiles feature regular time steps. Two different time steps are supported:
- Each hour
- Each 15 minutes
The electrical consumption for a given time step is specified in kWh.
As the software supports 15-minute profiles, smart-meter measurements may be easily used in Polysun.
A wide range of pre-defined profiles are available for use in Polysun.
User-defined profiles may also be added, including, for example, any available reference profiles.
If the simulation of a given system requires that a special profile be used, this may be created, for example, using the Load Profiles Generator programme.[1] This software generates profiles based on a so-called “desire model“, allowing the creation of a wide range of profiles.
Electricity Consumption Profiles
The component internal grid and electric consumers calculates and displays different values for self-consumption. The corresponding tooltips (hover over the corresponding line with your mouse for two seconds) show the definition of the values and the calculation behind it. In the component results, self-consumption and total consumption are individualized under electric consumers and internal grid as follows:
- Degree of self-sufficiency (Raut = Ess/Ecs): The degree of self-sufficiency corresponds to the relation between self-sufficiency and total consumption.
- Self-consumption fraction (Rocs = Eocs/Eacp): The self-consumption fraction equals the relation between self-consumption and self-production.
- Self-consumption (Eocs = min(Eacp,Ecs+EbchPV+EbchCG)): The self-consumption equals the share of the own power generation that is used to cover consumption.
- Self-sufficiency (Ess [kWh] = Edcs [kWh] + EbdisPV [kWh] + EbdisCG [kWh]): The self-sufficiency equals the share of the consumption that is covered by the own production.
- Direct consumption fraction (Rdcs = Edcs/Ecs): Equals the percentage of the power generated that is consumed directly afterwards.
- Direct consumption (Edcs = min(Ecs,Eacp)): Equals the own power generated measured in kWh that is consumed directly afterwards.
- Feed-in ratio (Rocsp = 1-(Eocs/Eacp)): Is the share of power generated that is not consumed directly afterwards and fed into the external power grid.
- To external grid (Eteg = Eacp-Ecs-Ebch): Is the power fed into the external power grid.
- From external grid (Efeg = Ecs – Eacp + Eteg, for systems with batteries Efeg = Ecs – Eacp + Eteg + Lbtot): Is the electric energy withdrawn from the external power grid.
- Own AC production (Eacp): self-generated AC current.
- Electricity consumption of the profiles (Epcs): Sum of the electricity consumption of the hourly profiles.
- Electricity consumption (Ecs = Epcs+Ethcs): Sum of the electricity consumption from profiles and thermal components.
A collection of 1 min resolved consumption profiles that can be imported into Polysun is available for download https://github.com/VelaSolaris/polysun_loadprofiles_1min.
Video: Import of electrical consumption profiles
Electric Consumption of Thermal Components
The electrical consumption of thermal components is included in the electrical consumption Ecs if the components electrical consumer and electrical grid are present in the system.
Table: List of thermal components
| Component | Value |
| Heat pump | Eaux |
| B/W or W/W heat pump | Eaux |
| Pump | Epar |
| Internal heat generator (electric) | Eaux |
| Recooler | Fan speed |