Support

How do forecasts work?

OnSun uses weather data and solar forecasting algorithms to estimate your solar generation throughout the day. Forecasts consider factors like cloud cover, time of year, and your location. Because solar generation depends on many uncontrollable factors—such as weather, shading, and system performance—forecasts are estimates only and real-world results may differ.

What forecast interval does OnSun use?

OnSun's forecasting models analyse weather and solar radiation data to estimate your solar generation. The time resolution of your forecast depends on your location.

In most regions, forecasts are provided in hourly intervals. In areas with higher-resolution meteorological coverage, our models can produce more granular 15-minute interval forecasts. Your location therefore determines the time step resolution you see in the app.

OnSun automatically uses the highest resolution available for your region to give you the most accurate forecast possible.

Configuring your solar settings

For the most accurate solar forecasts, it's worth taking a few minutes to configure your solar system settings. Here's what each setting means and how to find the right values:

Still unsure about a setting? Check your solar installer's paperwork or your inverter's display/app.

Is the forecast significantly off? If your actual solar production is consistently very different from what OnSun predicts, we'd like to hear from you. Send us screenshots of your solar app alongside OnSun's forecast, along with your configuration details and location. This data helps us improve the forecasting model.

How are savings calculated?

Savings estimates are based on your forecasted solar generation and typical energy rates. The app compares running appliances during peak solar times versus importing from the grid. These are projections only; actual savings will depend on your specific energy plan, usage patterns, and real-world solar output.

Subscription & billing

OnSun offers free and paid subscription tiers. Subscriptions are managed entirely through your device's app store (Apple App Store or Google Play Store). This means:

• Subscriptions auto-renew unless cancelled at least 24 hours before the end of the current period
• Billing is handled by Apple or Google; we do not process or store payment information
• You can manage or cancel your subscription in your Apple ID or Google account settings
• No refunds are offered for partial periods, except where required by law

How to restore purchases

If you've previously purchased a subscription or upgraded to Pro, you can restore your purchase through the app. Open OnSun, go to Settings, and tap "Restore Purchases." If you continue to have issues, ensure you're signed in with the same Apple ID (iOS) or Google account (Android) used for the original purchase.

Location accuracy guidance

For accurate solar forecasts, OnSun needs your approximate location to calculate sun angles and local weather conditions. The app requests location permission when you first set up. You can update your location at any time in Settings. If you prefer not to share your precise location, you can manually enter your coordinates (latitude and longitude).

Block load profiles

OnSun uses simplified appliance load profiles to make solar scheduling straightforward. Real-world appliances often have variable power draw—heating elements cycle on and off, motors ramp up, and rinse cycles use less power than wash cycles.

While "block" or variable profiles don't perfectly match our steady-state estimates, every appliance behaves differently. Modeling each unique profile would create an overly complex experience that detracts from OnSun's core purpose: helping you align appliance usage with your solar generation.

Our scheduler treats the total energy needed as a flexible block that fits within your solar window. This approach works well for most households regardless of internal power variations.

If you need detailed block-profile scheduling (for example, to avoid peak tariff periods or coordinate with home battery cycling), please contact us. Our app architecture supports this feature, and we'd welcome your feedback to prioritise it.