Lookup Table inverters model DC to AC power conversion efficiency by interpolating values from a look up table. The data structure has been designed to be used with data contained in the Inverter Performance Test Summaries available at:
All of the data needed for this object can be found there by make and model of inverter. The core of the data set is a 3x6 matrix of efficiency at different voltage and power levels. These form the look up table used in the model. Note that EnergyPlus PV models currently model only power and not the voltage and current situation. Therefore, only the nominal voltage data are used. This is the middle row of data in the Go Solar summaries.
The name of the inverter entered here must also be unique across all other inverters in the model.
Select the type of inverter from the options below:
The schedule that describes when the inverter is available. If the inverter is scheduled to not be available, by scheduling a value of 0, then it cannot produce AC power and will not consume ancillary power during standby. Any non-zero schedule value means the inverter is available to produce AC power and consume ancillary power during standby. If the Inverter is scheduled to be unavailable but it is being supplied with DC power anyway, then the energy is dissipated as heat.
Rated maximum continuous output power
This field contains the rated maximum continuous output power (in W).
Night tare loss power
This field contains the “night tare loss” (in W). This is modelled as ancillary power consumed during standby.
Nominal voltage input
This field contains the nominal DC input voltage (in V). This is “Vnom” in the Go Solar test summaries.
EFFICIENCY AT NOMINAL VOLTAGE
At 10% Power
The fractional efficiency at nominal voltage and 10% power.
At 20% Power
The fractional efficiency at nominal voltage and 20% power.
At 30% Power
The fractional efficiency at nominal voltage and 30% power.
At 50% Power
The fractional efficiency at nominal voltage and 50% power.
At 75% Power
The fractional efficiency at nominal voltage and 75% power.
At 100% Power
The fractional efficiency at nominal voltage and 100% power.
HEAT GAINS TO ZONE
Attach to a zone
If the inverter’s losses are to be modelled as heat gains to a zone in the building thermal model then check this option. Otherwise inverter losses are considered to be lost to outside.
When including inverter losses and heat gains to a zone select the building zone where the inverter is located.
This field contains the fraction of inverter thermal losses that enter the zone as long-wave thermal radiation. This should be a factor between 0.0 and 1.0. The balance of the losses is convective. This data is only required when including inverter losses and gains to a zone.