Rooftop Rooftop Solar Forecasts

Solar power forecasting for rooftops - just one, or thousands.

Solar power forecasts for rooftop sites via API

Connecting your rooftop site with our rapid-update cloud nowcasting system and delivering 30 minute resolution power forecasts out through 7 days ahead via our API. Set-up your test site within minutes!

  • Capture Shading Impacts
  • Detect Degradation, Estimate Tilt
  • Identify Azimuth Angles
  • Individualise Cloud Impacts
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PV Tuning: Forecasting for your PV system

Shading? Soiling? Split arrays? Unsure of system specs? No problem! Take advantage of our PV tuning technology, which learns from your shared power measurements to individualise the forecast. Tune a site with as little as 6 weeks of historical data. Or POST live data directly to our API to keep us up to date as your site changes.

Proven customer use cases for rooftop solar forecasting:

  • Accurately plan and manage home energy use around solar intermittency

  • Optimising charge/discharge of home energy storage systems

  • Managing peak demand charges for large commercial energy users

  • Enable smart energy trading strategies across rooftop solar portfolios

  • Conduct DIY experiments or build new products/apps

  • Conduct research (Solcast offers free access to this product for non-commercial use)

Features and benefits

  • Live power forecast and estimated actuals data
  • Global coverage, use one API wherever you operate
  • PV Tuning included: captures the impacts of shading or other de-ratings from your measurement data
  • Privacy agreement for your shared data, ability to permanently delete


Data Specifications


PV Power (kW)

Forecast probabilities

10th and 90th percentile forecasts provided for: PV Power (kW)

Spatial coverage

All continents (Rapid update actuals and forecast data) Global (forecasts)

Time granularity

30 minutes (period mean only)

Update frequency

Every 10 or 15 minutes

Time span (Forecast)

Present time to +7 days ahead

Time span (Realtime)

7 days ago to present time

Power modelling – Included Metadata options

Maximum installed capacity

2,000 kW

Tracking systems supported?


Minimum metadata you need to provide

latitude, longitude (and capacity, if you don’t upload or post measurements)

Additional metadata you can share for better forecast

azimuth, tilt, AC capacity, DC capacity, loss factor, install date

Multiple tilts/tracks supported?

No. You can create and group multiple sites, or you can use tuning.

Power modelling - Included tuning options

Detects your site specifications from measured data?


Learns about shading, slope and other site-specific factors?


Minimum period of measurement data required to start improving your forecast with tuning

6 weeks (12 months is ideal)

Minimum measured data parameters we require

Total power output (kW)

Additional measured data parameters you can post for a better forecast


Allowable time granularity of your measured data

One-off historical upload:

  • 1 to 30 minutes (5 minute means every 5 minutes is ideal)

Live data posting to Solcast API:

  • 5 to 30 minutes (5 minute means every 5 minutes is ideal)

Automated HTTP post of live or recent measured data to our API, for continuously updated tuning and live accuracy tracking?


Privacy agreement for your measurement data?


Ability to permanently delete your measurement data?


Check it out for yourself, add a rooftop site and start testing

You can get started now by signing up for our API, and then adding your site location, a name and a few basic details about its technical specifications.

Within minutes, we’ll have your forecasting tools ready for use with little hassle and no upfront costs to trial.

Once your rooftop site is setup in our system, you can send us an upload of recent historical data (or join and tell us your site ID) to take advantage of our proprietary PV tuning algorithms to improve your forecasts.