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Solar energy and radiation issues.

Dear VisualCrossing,

How should I use the history API if I want to know the sum of daily solar energy for a given coordinate.
The documentation says "For solar energy, the daily value is the sum of the hourly values."  So if I use a query with aggregateHours param set to 24, can I assume that the solarenergy result is the total amount for the given day? 

If so, the value seems very unreliable.

Let's take this query for example (API key excluded)

https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/weatherdata/history?aggregateHours=24&combinationMethod=aggregate&startDateTime=2021-08-25T00%3A00%3A00&endDateTime=2021-08-25T00%3A00%3A00&maxStations=-1&maxDistance=-1&sendAsDatasource=true&contentType=json&unitGroup=metric&locationMode=array&key=[KEY_EXCLUDED]&dataElements=all&sourceDatasourceTable=%7B%22name%22%3A%22WxSourceData1%22%2C%22id%22%3A%22WxSourceData1%22%2C%22isPrimary%22%3Atrue%2C%22analyzeLevels%22%3Afalse%2C%22rowDateTimeColumnIndex%22%3A-1%2C%22defaultDateTimeFormat%22%3A%22yyyy-M-d'T'H%3Am%3As%22%2C%22columns%22%3A%5B%7B%22isKey%22%3Atrue%2C%22name%22%3A%22ID%22%2C%22id%22%3A%22id%22%2C%22type%22%3A%22string%22%7D%2C%7B%22isKey%22%3Afalse%2C%22name%22%3A%22Name%22%2C%22id%22%3A%22name%22%2C%22type%22%3A%22string%22%7D%2C%7B%22isKey%22%3Afalse%2C%22name%22%3A%22Address%22%2C%22id%22%3A%22address%22%2C%22type%22%3A%22string%22%7D%5D%2C%22rows%22%3A%5B%5B%22ffaceac6a8%22%2C%22Wien%22%2C%2248.25454439380866%2C16.605125810900645%22%5D%2C%5B%220effdc55c4%22%2C%22Cralsheim%22%2C%2249.1097%2C10.0553%22%5D%5D%2C%22layerDataContext%22%3A%7B%22FieldJoins%22%3A%22%7B%7D%22%2C%22useGeoJsonGeometry%22%3A%22true%22%2C%22attributeId%22%3A%22id%22%2C%22shapeType%22%3A%221%22%2C%22onDemandTileGeneration%22%3A%22true%22%2C%22joinLayerColumns%22%3A%22address%22%2C%22contextType%22%3A%226%22%2C%22attributeName%22%3A%22%22%2C%22FieldValues%22%3A%22%7B%7D%22%2C%22addressFields%22%3A%22address%22%7D%7D

Both locations has Clear conditions, they are not far off from each other by latitude but the first solarenergy has value of 20.9 while the other only 0.5. They shouldn't be this far from each other.
I also queried a whole year and the solarenergy value for location 49.1097,10.0553  is very very low. I'm certain it is not correct.
The API response's column tells me that the unit for solarenergy is J / m^2. This also seems wrong. Maybe MJ/m^2 ?

Please help me to understand how to use the results correctly, and how can I tell if the results are incorrect or not. According to the given example, the solarenergy or solar radiation fields seem unreliable.

Thank you for your help,
BR
Daniel

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