Forecast and weather
Solar forecasts from Solcast or Open-Meteo, and the weather.
Metrics
Metric roles, the battery estimate, combined metrics and the list of every reading.
Prices and savings
Grid, generator and battery costs, and how your savings are worked out.
Settings → Forecast and weather sets up the forecast of how much your panels will produce, along with the weather for where you are. Switch on Show the solar forecast to start.
Location
Enter your Latitude and Longitude, or press Use my location to let your browser fill them in.
Panels
If you have groups of panels that differ in size, tilt or direction (an east roof and a west roof, for example), add each group as its own array. The forecast works each one out and adds them together.
For each array, enter:
| Field | What to enter |
|---|---|
| Array name | Anything that helps you tell them apart, such as "East roof". |
| Peak capacity | The array's size in kWp. |
| Tilt | The angle in degrees: 0 is flat, 90 is upright. |
| Facing | The direction the panels face, in degrees: 180 is south, 90 is east. |
| Solcast resource ID | Optional: this array's own rooftop site in Solcast. |
Loss factor is the share of their rated output your panels really deliver, from 0 to 1; 0.9 suits most systems. Installation date is optional.
Providers
| Provider | How accurate | Cost |
|---|---|---|
| Open-Meteo | Reasonable: a forecast for your general area | Free, no key needed |
| Solcast | Better: modelled for your actual rooftop | Free hobbyist plan with about 10 requests a day |
Forecast provider and Weather provider can each be set to Auto (Solcast once it's set up, otherwise Open-Meteo), Solcast or Open-Meteo.
To use Solcast, create a rooftop site in the Solcast toolkit, then enter your Solcast API key and Solcast resource ID. If one site covers all your arrays, put its ID here; otherwise give each array its own ID above. Epilykos keeps each Solcast forecast for 3 hours, which works out at about 8 requests a day and keeps you within the free plan.
Press Test forecast to check that it all works.
When the forecast isn't available
If Solcast's daily allowance runs out, or a provider can't be reached, Epilykos raises the Solar forecast unavailable event. You can choose to be told about it in Notifications.
Where the forecast shows up
You'll see it on the forecast and weather cards, in Day
totals and Energy day, in the Telegram /forecast command, and in scheduled forecast reports
such as a "low solar tomorrow" warning.
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