NREL’s PVWattsTM calculator determines the energy production and cost savings of grid-connected photovoltaic (PV) energy systems throughout the world.

It also allows homeowners and installers.  Moreover manufacturers and researchers to easily develop estimates.  I mean for and of the performance.  All of hypothetical PV installations.

How the PVWatts Calculator Works

The PVWatts calculator works by creating hour-by-hour performance simulations.  All that provide estimated monthly and annual energy production.  Then they go in kilowatts and also energy value. Users can also select a location.  For then they choose to use default values or their own system parameters

That’s for size and electric cost and array type.  In addition and don’t forget tilt angle and azimuth angle.

In addition, the PVWatts calculator can provide hourly performance data for the selected location.

Then they bust out a great report.  All using typical meteorological year weather data.  I mean for the selected location.  So the PVWatts calculator determines the solar radiation incident of the PV array and the PV cell temperature.

Most noteworthy and for each hour of the year. So the DC energy for each hour is calculated from the PV system DC rating.  In addition to the incident solar radiation.  Finally and then corrected for the PV cell temperature. Then the AC energy for each hour is calculated by multiplying the DC energy by the overall DC-to-AC derate factor.  Also don’t forget to adjusting for inverter efficiency as a function of load. Hourly values of AC energy are also then summed to calculate monthly and annual AC energy production.

Source: NREL

Versions of the Calculator

In conclusion, the green living application or the PVWatts calculator is also available in two versions. First of all, Site Specific Data Calculator (Version 1) allows users to select a location from a map.  In addition, they also now offer to text a list.  I mean of database approved pre-determined locations.  And I also forgot this version is for all throughout the world.

In addition, Grid Data Calculator (Version 2).  For it only allows most interestingly users to select any location.  Yet, for that I mean only in the United States.

Finally, the PVWatts calculator was developed by NREL.  Sorry! For I mean National Renewable Energy Laboratory (NREL).  Then they have a division called: Electricity, Resources, and Building Systems Integration Center.