Solcast, a global data services company, is known for crunching an incredible amount of weather data in the name of solar. In particular, the weather satellite imagery they collect every 5-15 minutes from 5 weather satellites all around the world stacks up fast – with more than 30 TB of imagery collected in a single month! Using this information, they process more than 600 million solar forecasts around the world every hour, delivering them to grid operators like EVN Vietnam to support their day to day operations.
Until recently, effective visualisations for how the process of converting satellite imagers into estimates of solar radiation or solar power haven’t been available in real-time. But with their release of a new browsable archive of live animation solar radiation maps, that’s now changed, so that anyone can review how solar variability unfolds on a given day, across the world.
Solcast’s new browsable Solar Radiation Map Archive is a welcome addition to the variety of data tools solar asset management and grid operators around the world use to manage solar generation. Each day, Solcast is uploading new regional animated maps of yesterday’s solar irradiance to their website, so that anyone around the globe can track the impact of cloud cover on their solar operations.
The new map archive tool has proven an excellent resource for the detective work involved on why/how solar energy generation sites, big, small and in-between, have performed on a given day. One example of its application is for investigating why a given solar system perform poorly on a particular day. This is actually incredible common question in the asset management space, where just a few days of intense cloud cover can throw-off an entire quarter of revenue estimates. But until now, it has been difficult to make the connection between revenue and cloud cover impacts.
Another use case is for investigating the impacts of cloud cover on behind the meter solar, which as grown very quickly in South Korea, Japan and China over the past several years. Behind the meter solar creates many demand forecasting challenges, and is a growing source of trouble for utilities around the world. And while such generation assets can feel ‘invisible’ to the utility, the behaviour of behind the meter solar is primarily driven by cloud cover. Without including the impacts of cloud cover on the demand, they can quickly throw the proverbial wrench into a load forecasting engine! Utilities experiencing unexplained variance in their demand forecasts, are now looking up a given day in the Solar Radiation Map archive, to quickly reveal the cloud cover conditions for a given day. This is often the case when thick cloud covers over a high solar penetration region, which increases apparent demand. The opposite is also true when a quick clearing of cloud cover suddenly drops it.
Speaking of fast moving, fast changing cloud cover, seasonal thunderstorms have proven to be a source of solar variability in Southeast Asia, particularly in Vietnam. Vietnam now operates over 4.4 GW of utility scale solar, and with its low latitudes and complicated geography it experiences routine and intense thunderstorm activity. The Solcast Solar Radiation Map tool has now enabled quick visualisations of the convective activity that frequently interrupts solar generation and can lead to disturbances in the transmission networks there.