FMI to forecast solar, wind power production

A new service is available for monitoring the energy weather, said the Finnish Meteorological Institute (FMI) in a press release on Monday.

The FMI's solar and wind power production forecasts convert the sunshine and wind over the following few days into kilowatt-hours. The forecasts will be available on the FMI website at free of charge.

The new service is a helpful tool for households and communities that use solar and wind power.

“For example, the information enables them to anticipate when plenty of solar power will be available so that they can time their consumption accordingly. On the other hand, consumption can be reduced if cloudy and windless weather has been forecast because it means that wind power will be scarce,” said Anders Lindfors, Research Professor of the FMI.

The solar power production forecast shows sunshine as the power produced by a solar power plant at different locations over the following few days.

“Based on the information in the weather forecast model, it is first estimated how much solar radiation will fall on the inclined surface of the solar panel. Because the efficiency of solar panels does not depend only on the radiation conditions, but also on the temperature of the panels, the efficiency corresponding to the weather conditions at a given time is then calculated from the radiation, temperature and wind data. The forecast solar energy production is obtained by combining all this information,” said Anders Lindfors.

The solar power plant used in the forecast is assumed to be a power plant with a nominal power of 1 kWp (kilowatt-peak), facing south and installed at an angle of 30 degrees from the horizontal level.

The nominal power has been selected to make the forecast easy to convert: the power produced by a solar power plant with a peak power of 5 kWp and the same orientation will be five times the forecast power.

The wind power production forecast shows the total power production of wind turbines in Finland over the following few days.

“The forecast is obtained by combining the forecast wind data with the location data of Finland's wind turbines. In addition, the data on the hub height and the power curve of each known wind turbine in Finland are used in the calculation,” Lindfors added.

The solar and wind power production forecasts are based on the weather data produced by the joint Nordic MetCoOp weather forecasting system.