Hourly Report CSV

In this article:

CSV Overview

HelioScope models the performance of the array for every hour of the year. When you run a simulation and open the  Production Report, it will provide a summary of that data. If you want to view the hourly data that underpins the report click the gray CSV button next to the PDF button (highlighted below):

The CSV file will contain 8760 rows, one for every hour of the year. Each column represents one of the steps in the HelioScope simulation starting with the weather file data and running through each of the losses that occur in the system. If you just want to analyze the actual production of the array you'll want the last column "grid_power". Having trouble finding column labels? Just select the first row in excel and enable text wrapping to see the full title for each column.

Sample Excel Models

The 8760 CSV file is always in the same format so you can build Excel models that reference a second tab and just drop the CSV into the model. The HelioScope team has developed a few Excel models to get you started that are linked below:

  • 12 x 24 spreadsheet: converts the 8760 into a monthly x hourly table so you can quickly assess when the array produces energy throughout the year. 
  • Comparison spreadsheet: allows you to compare two CSV files side by side. Easily identify why one design produces more than another. 
  • Monthly losses: the production report summarizes the losses for the entire year. This spreadsheet breaks out each loss by month allowing you to see when the losses occur throughout the year. 
  • Max Day Curve: shows the production curve for the highest producing day of the year. 
  • 8760 with zeros : adds a zero to empty values for easier copying & pasting.

International CSV Exports (Commas vs. Decimal Points)

Europe and America use periods and commas differently when separating between decimal points and thousands. 

  • American: 0.50%   150,000
  • European: 0,50%   150.000

HelioScope uses the American formatting for decimal points. This can cause issues when importing HelioScope CSV files internationally if your text to column settings interpret the decimal point as a thousands separator. The article from Microsoft below describes how to change your import settings (step 3 of 3 describes the decimal setting):  Microsoft Support Article

CSV Column Explanations:

Quick note: everything after column Y in the CSV is in watts. Each row represents an hour so the units are equivalent to watt hours. The data is in hour-beginning format, so the hour 1/1/YY 0:00 represents midnight to 1:00am. 

Column Name Description Units
Weather Values
hour_index
The hour of the year. Between 1 and 8760 Integers
timestamp Date and time of the simulation MM/DD/YYY
global_horizontal_irradiance the total amount of sunlight available at a given moment, based on a collector that is oriented perfectly flat on the ground. This includes both the direct and diffuse components of the sunlight. W/m 2
direct_normal_irradiance Direct Normal Irradiance (DNI) is the amount of solar radiation received per unit area by a surface that is always held perpendicular (or normal) to the rays that come in a straight line from the direction of the sun at its current position in the sky.  W/m 2
diffuse_horizontal_irradiance the indirect sunlight that is available to a collector that is oriented flat on the ground. This includes the general brightness of the sky, as well as reflected light. The best way to visualize this irradiance is to picture a person’s shadow on a sunny day. The ground under the shadow is not totally dark, even though the direct component has been removed. The remaining sunlight is the diffuse irradiance. W/m 2
dry_bulb_temperature the air temperature at a given point in time. Note that this is not the same as the cell temperature – that is calculated separately based on a few inputs. ºC
windspeed the speed of the wind. This is used in the cell temperature calculations. m/s
albedo Reflected irradiance represents sunlight that is reflected off the ground around an array. It is calculated based on an albedo coefficient (which is the portion of the incident irradiance that is reflected), and the share of the ground that is visible from the module. The albedo coefficient is typically 0.2, though it can be higher during snowy periods in cold climates.
Irradiance Values
solar_altitude_angle Solar Altitude Angle Degrees
solar_azimuth_angle Solar Azimith Angle (0º is true North) Degrees
solar_incident_angle Average solar incident angle relative to module orientation (0º is normal to module orientation) Degrees
horizon_elevation_angle Elevation of horizon at solar azimuth angle Degrees
adjusted_ghi GHI value after accounting for  spectral analysis (if using thin film modeling).  W/m 2
poa_direct_irradiance Average Direct (Beam) Irradiance Incident on the Plane of Array of the Modules W/m 2
poa_diffuse_irradiance Average Diffuse Irradiance Incident on the Plane of Array of the Modules W/m 2
poa_reflected_irradiance Average Reflected (Albedo) Irradiance Incident on the Plane of Array of the Modules W/m 2
shaded_direct_irradiance Average Direct (Beam) Irradiance Incident on the Plane of Array after Shading effects W/m 2
shaded_diffuse_irradiance Average Diffuse Irradiance Incident on the Plane of Array of the Modules after Shading effects W/m 2
shaded_reflected_irradiance Average Reflected (Albedo) Irradiance Incident on the Plane of Array of the Modules after Shading effects W/m 2
effective_direct_irradiance Average Direct (Beam) Irradiance Incident on the Plane of Array after Shading and IAM effects of the Modules W/m 2
effective_diffuse_irradiance Average Diffuse Irradiance Incident on the Plane of Array of the Modules after Shading and IAM effects W/m 2
effective_reflected_irradiance Average Reflected (Albedo) Irradiance Incident on the Plane of Array of the Modules after Shading and IAM effects W/m 2
soiled_irradiance Average Irradiance available to Modules after all effects and soiling factor W/m 2
total_irradiance Average Irradiance available to Modules after all effects, soiling factor, and any defined irradiance variation W/m 2
Power Values
nameplate_power Total nameplate power of system, Irradiance * Module Nameplate W
avg_cell_temp Average Module Cell Temperature ºC
module_irradiance_derated_power Total Module Power after derating for Irradiance W
module_mpp_power Total Module Power after derating for Irradiance and Temperature W
module_power Total Module Power under array operating conditions, e.g. including any losses due to mismatch or operation away from module MPP W
optimizer_input_power Total power input into power optimizers in the array W
optimizer_output_power Total power output from power optimizers in the array, ie including optimizer operational efficiency W
optimal_dc_power Optimal system power unconstrained by inverter power range W
optimal_dc_voltage Optimal system voltage unconstrained by inverter voltage range V
inverter_overpower_loss Power loss due to constraining power down to inverter max power rating W
inverter_underpower_loss Power loss due to insufficient power for inverter minimum power rating W
inverter_overvoltage_loss Power loss due to constraining voltage down to inverter max voltage rating W
inverter_undervoltage_loss Power loss due to insufficient voltage for inverter minimum voltage rating W
actual_dc_power Total DC system power after accounting for inverter operating range W
actual_dc_voltage Operating system voltage after accounting for inverter operating range V
ac_power Total AC System Power, after accounting for inverter efficiency, excluding AC transmission losses to interconnect W
grid_power Total AC System Power, including AC transmission losses to interconnect W