Enter your postcode, tell Sol your best solar day, and get a personalised 7-day generation forecast — no engineer, no complicated setup. Meet the app built for real solar homeowners.
Why we built Sun Hours
If you've ever tried to figure out what your solar panels are actually going to generate, you'll know the problem. The apps that exist either require you to sign into your inverter, dig out your installation paperwork, configure API keys, or navigate dashboards built for engineers — not homeowners.
We thought there had to be a simpler way.
Sun Hours was built on a single idea: your solar panels have a best day. A day when the sky is clear, the sun is high, and the output number on your inverter makes you smile. Tell us that number, drop a pin on your location, and we'll do the rest.
Meet Sol ☀️
Sol is the face of Sun Hours — a little sun with big sunglasses and an even bigger mission: to make solar energy data accessible to everyone.
Sol lives inside the app, reacting to your forecast. On a bright, high-generation day Sol is cool and confident. When clouds are rolling in, Sol is watching. Sol represents the idea that solar shouldn't be intimidating — it should be your energy, clearly shown.
How it works
Getting started with Sun Hours takes about 30 seconds:
Step 1: Drop your pin
Enter a UK postcode or tap anywhere on the map. Sun Hours works globally, but is optimised for the UK where data coverage is excellent.
Step 2: Your best solar day
This is the key insight that makes Sun Hours different. Instead of asking you for system specs — panel brand, inverter model, roof orientation, tilt angle — we ask one simple question: what's the most kWh your system has ever generated in a single day?
This single number captures everything about your specific installation. It bakes in your roof angle, any shading, your inverter efficiency, panel degradation — all of it. If your best day produced 18 kWh, that tells Sol everything it needs to know.
Step 3: Your 7-day forecast
Sun Hours fetches real weather data from Open-Meteo and compares the upcoming sun conditions to your location's historical solar irradiance from NASA POWER. It then scales your best-day output accordingly — so if tomorrow is forecast to be 70% as sunny as your best ever day, your forecast will show roughly 70% of your peak output.
The result: a 7-day solar generation forecast that's personalised to your panels, your roof, your location.
No complicated setup. That's the point.
Every other solar app we tried asked for things most homeowners don't know off the top of their head. System capacity in kWp. Panel efficiency percentage. Performance ratio. Inverter model.
Sun Hours asks for none of that. The philosophy is: if you've had solar panels installed, you've already done the hard part. Now we just want to help you understand what those panels are going to generate, in plain English, presented clearly.
Available now on Android. iOS coming soon.
Sun Hours is available on Android right now via the Google Play Store. iOS is in development and coming soon.
We'd love to hear what you think. If you have feedback, questions, or feature requests, use the Support page to get in touch — Sol is listening. 🕶️
Try Sun Hours free — Android now, iOS coming soon
Enter your postcode, your best solar day, and get a 7-day forecast in under a minute.
Get it on Google Play →