SoDa - Description of the SoDa Products

Description of the SoDa Time Series

Temporal series of solar data for a point
How are computed the HelioClim irradiation values

Temporal series of solar data on a point

	Horizontal Plane global radiation	Inclined Plane global, direct, diffuse	Plane normal to sun rays (DNI) global, direct, diffuse
Month	HCmonth HC-1 and HC-3	HCmonthIncl HC-3	HCmonthDNI HC-3
Week	HCweek HC-1 and HC-3	-	-
Day	HCday HC-1 and HC-3	HCdayIncl HC-3	HCdayDNI HC-3
Hour	HChour HC-3	HChourIncl HC-3	HChourDNI HC-3
1 min to 30 min	HC15 HC-3	HC15Incl HC-3	HC15DNI HC-3

Exemple : HCmonth provides global monthly radiation values on a horizontal surface. Available solar databases: HC-1 and HC-3.
The name of the products for pay are composed of HC, followed by the temporal step and the plane orientation (horizontal if not specified). HC and designates the HelioClim solar databases for which the product is avalaible: HelioClim-1 (HC-1) and -3 (HC-3). More information on the bases and their uncertainties.

Test the free version of these products: every product for registered users has a free counterpart temporally limited to 2005 for HC-3. This allows any user to test services before registration and to check their relevance to the needs.

Top of page

How are computed the HelioClim irradiation values

We remind that a MSG-2 image, or "slot", is acquired every 15 min. The purpose of this table is to explain the discrepancy that might exist between two agglomerations of radiation values: for instance between the 15 minutes data and the monthly/yearly data from HC3.

Request for a radiation value with a frequency of	with the assumption that	SoDa result
from 1 to 10 min	the 15 min slot is available	SoDa performs an intelligent oversampling
1 hour	the four slots of the hour are missing	-999 (missing data)
1 hour	at least one 15 min slot is available	the hourly value is interpolated.
1 day	all the slots of the day are missing	-999 (missing data)
1 day	at least one slot of the day is available	the radiation is interpolated along the day
1 month	all the slots of the month are missing	-999 (missing data). The only case if the month of July 1986
1 month	at least one slot in the month is available	the average irradiation values of the available days are computed and multiplied by the number of days in the month
1 year (monthly service)	all the months are available	the average of the monthly values is retained
1 year	at least a month is missing	the annual values is computed thanks to the available days in this year. The average daily values is computed and multiplied by the number of days in the year

Be careful to discard missing values (-999) when suming up the columns in a SoDa output CSV file. If not discarded, the -999 values are summed up as well, leading to incorrectly low values.

Example of a monthly basis request: if only 25 daily values were available for the month of january, the average irradiation values of the 25 days is computed and multiplied by the total number of days of the month (31).

Top of page

Services for Professionals in Solar Energy and Radiation