How predictable is DNI? An evaluation of hour ahead and day ahead DNI forecasts from four different providers
نویسندگان
چکیده
Forecast DNI values in hourly resolution for one day ahead are evaluated by a comparison with pyrheliometer ground measurements. Three months of such day ahead forecasts from four different providers for a site close to Questa, NM, USA are analyzed firstly by calculating the RMSE and the mean bias error. Secondly, cumulative distributions of the DNI forecast errors are calculated as they better suit the context of a utility’s use of the forecast. Hour ahead forecasts are only briefly adressed due to the high uncertainty linked to these forecasts.
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