Clouds are always changing, so why stick with the old forecast?
A key challenge for solar energy suppliers and their electricity markets and networks is the fact that the amount of solar radiation reaching the Earth’s surface is constantly changing. This is referred to as ‘solar intermittency’. There are two main causes of this intermittency – time of day/year and cloud cover.
The amount of solar radiation reaching a location changes as the intensity of solar irradiation changes over the course of day and night. This is very predictable and can be forecasted easily. But cloud cover is a whole different ball game! One cloud can vary enormously from another cloud. And clouds can form, change and dissipate within hours or minutes. These fast-moving and rapidly-changing clouds require forecasting solutions that are just as speedy.
Solcast has developed the ability to measure and forecast cloud cover in order to rapidly update solar forecasts.
Rapid Update Forecasting update cycles, globally
What is Rapid Update Forecasting?
Rapid Update Forecasting means knowing the exact locations and properties of clouds affecting a solar asset. This includes knowledge and active tracking of cloud opacity (thickness), height, movement and tendency.
Older forms of solar forecasting relied on Numerical Weather Prediction models as the sole meteorological input. These models are a crucial source of information when making a solar forecast for tomorrow and beyond, but they don’t actually track or predict cloud cover and are therefore missing large pieces of information affecting forecast accuracy.
How does Solcast produce Rapid Update Forecasts?
Solcast goes all-out when it comes to Rapid Update Forecasts and include this capability in all forecasting products. Using five high-resolution weather satellites, Solcast generates over 600 million forecasts every hour. The first 4 hours of forecasts are updated every 10 to 15 minutes with each new satellite scan. For Utility Scale solar farm products, forecast resolution is pushed even further to provide you with 1 minute resolution forecasts! The volume of data and forecasts managed by Solcast allows for the rapid generation of ensembles of individual forecasts for each time-step. This is captured as uncertainty in any given weather regime and communicated back to customers.
Rapid update solar forecasting in action over the United Kingdom for 17 Match 2018. Forecasted cloud appears in the right graphic and actual observed cloud in the left graphic.
Rapid access to Rapid Update Forecast products
You can instantly evaluate rapid update forecasting solutions by signing up for the Solcast API service. Within minutes you’ll have access to trial forecasting tools with little hassle and no upfront costs.