Solar Irradiance Data - Everywhere You Need It

Accurate solar irradiance and weather data with global coverage: Historical, live and forecast

Our purpose at Solcast is to enable you to build, operate and manage the solar powered future. And our mission is deploy the data and tools you need to do just that! And no source of information is more important for the solar energy industry than solar radiation data. Our team believes we have the most accurate and most widely available historical, live and forecast solar radiation data available, and we are committed to improving it every week. But don’t take our word for it! We welcome you to test it out and tell us what you think.

A Fleet of 5 Weather Satellites Means the Data You Need - Anywhere

Using a fleet of five weather satellites, we operate a rapid-updating solar radiation database covering all continents and most major island groups (outside of the polar regions). This database of our historical data reaches back more than 10 years, through to recent, live and forecast data available for retrieval via the Solcast API service.

GHI, DNI and DIF solar irradiance data

This API allows for easy manual download or automated fetching of historical, live and forecast solar radiation data, and includes commonly required fields such as Global Horizontal Irradiance (GHI), Direct Normal Irradiance (DNI), Diffuse Horizontal Irradiance (DHI) and a selection of other related weather variables, including temperature and cloud (check out our API documentation for more details).

Our customers use our solar irradiance and weather data to:

• Quickly and cheaply prospect and develop new solar projects
• Create or improve in-house solar power forecast modelling systems
• Conduct DIY experiments or build new products/apps
• Estimate PV system yield with modelling tools such as PVSyst
• Test and commission utility scale solar farms
• Conduct research (did you know, we offer free solar radiation data to University students and researchers?)

Check it out for yourself. Access the solar radiation forecasting, recent and historical data via our API!

We suggest you get started by checking our accuracy at a nearby measurement site of relevance to you. You can accomplish this by signing up for the Solcast API and using the latitude and longitude of that nearby site to grab recent solar radiation data via our Estimated Actuals.

One thing you’ll find is that, unlike our competitors, we don't cheat to nudge/train or "bend" our data to a nearby site. We have found that the benefits of such approaches disappear after travelling only a short distances away from the measurement site, and high-quality irradiance measurement sites are sparse (and most solar assets are over 500km from the nearest measurement site!). However, in cases where local solar radiation sites are available, such as for a solar farm, we can use your measured solar irradiance data to help improve the solar power forecasting through our ‘tuning’ technologies.

You can get started with your validation and testing in minutes, just register now for your FREE trial!