InstaCast™ provides ultra high resolution intra-hour solar forecasts. In order to anticipate local events in the forthcoming minutes, on-site images of the sky are the most valuable source of information. InstaCast™ processes those images to precisely and reliably forecast solar production, and deliver it in a convenient way.


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1-minute updates of the forecasts

1-minute forecast updates

With rapid forecast updates down to 1 minute, InstaCast™ offers unmatched short-term prediction of cloud events and solar production drops.

Easy interfacing with plant control sytems

Easy interfacing with plant control sytems

InstaCast™ has a proven compatibility with major energy management & power control solutions from the market.

100% offline mode for remote sites

100% offline mode for remote sites

An embedded version of InstaCast™ integrated within Reuniwatt’s sky imagers enables it to be used for microgrid projects in off-grid sites.



Sky image acquisition

Local images of the sky are acquired at a high frequency (1 min or less), as well as local weather measurements. Since the quality of this input data influences the accuracy of the intra-hour solar forecasts, Reuniwatt decided to design and build its own imagers, including the Sky InSight™, after testing various sky-imaging systems available on the market since 2011.

Irradiance & production forecast

Image processing methods are applied to distinguish the clouds from the sky and sun glares. A geometric calibration of the image permits a projection of the clouds and their cast shadows within the solar plant’s environment. Irradiance and production forecasts are derived from it. Besides, machine learning post-processing enables the forecasts to adapt to each site.

Formatting & transmission

Once computed, forecasts are formatted in a convenient way to be integrated in the plant’s management system, for an improved control of the plant. Reuniwatt’s InstaCast™ solution has a proven compatibility with major energy management & power control system providers. Last but not least, the intra-hour solar forecasts can be delivered locally in an embedded mode, or through the Internet.


Several variables available: solar irradiance (GHI/DNI/GTI…), output power, drops

1-minute updates

30-minute horizon at 1-minute granularity

10 m² spatial resolution

180° field of view / 2 km radius

Tailored distant (http, sftp…) or local (MODBUS) data transfer



You might also be interested in

Sky InSight™, our infrared sky imager

Intraday solar forecasts with HourCast™

Solar forecasting for microgrids and off-grid projects

Download our paper: forecasting for PV-diesel hybrid systems