Terms & conditions

1. Who we are

Wattlas is provided by Wattlas Ltd, a company registered in England & Wales under company number 17446591, with its registered office at 71-75 Shelton Street, Covent Garden, London, WC2H 9JQ, United Kingdom ("we", "us", "our"). These terms govern your use of the Wattlas website and app (together, the "Service").

2. The Service

Wattlas is an independent solar and battery monitoring tool. The Free tier estimates your expected generation from your system's specification and live weather data. The Plus tier additionally connects to your inverter, battery, and (where supported) EV charger to compare your actual generation and usage against that estimate. Wattlas is not affiliated with, endorsed by, or acting on behalf of any inverter, battery, or charger manufacturer.

Generation estimates are forecasts based on modelled weather and your declared system specification. They are estimates, not guarantees, and actual generation will vary with real conditions, shading, equipment condition, and other factors outside our control.

3. Your account

You must provide accurate information when setting up your account and system.
You're responsible for keeping your login credentials secure.
One household account may be shared with other members of that household (e.g. a second adult in the home) at our discretion; it isn't intended for unrelated third parties.
You can permanently delete your account and its data at any time from Profile > Account deletion in the app.

4. Subscriptions & billing

Plus is a paid, recurring subscription billed through our payment processor (Stripe). You can cancel at any time from the billing portal linked in your Profile; access continues until the end of the period you've already paid for. Prices may change with reasonable notice.

5. Connecting third-party accounts

Plus features may ask you to connect accounts or credentials for your inverter, battery, or EV charger manufacturer (for example SolarEdge, GivEnergy, myenergi Zappi, Ohme, Hypervolt, Easee, or Tesla). You do this voluntarily and can disconnect at any time from Setup. We only use these connections to read your own system's data on your behalf, and we aren't responsible for the availability or accuracy of a third-party manufacturer's own service.

6. Acceptable use

You agree not to:

Use the Service for any unlawful purpose, or in a way that could damage or overburden it.
Attempt to access another household's account or data without authorisation.
Reverse-engineer, scrape, or resell the Service without our written permission.

7. Disclaimers & liability

The Service is provided "as is". We don't guarantee it will be uninterrupted or error-free, and we aren't liable for decisions made based on estimates or comparisons the Service provides. To the fullest extent permitted by law, our liability to you is limited to the amount you've paid us in the 12 months before a claim arose. Nothing in these terms limits liability that can't lawfully be limited, such as for death or personal injury caused by negligence, or fraud.

The calculators on our website, including the roof panel calculator, give estimates only. Roof measurements come from aerial data or from figures you enter, and can differ from your actual roof. They are not a survey or a quote, and you shouldn't rely on them to buy or fit anything. Always have your roof measured and checked by a qualified installer first.

8. Data sources

Some figures in Wattlas are worked out from open data. We combine and model that data ourselves, so the estimates you see are ours, not the providers'. They don't endorse Wattlas.

The roof panel calculator uses Google Maps Platform for address search, roof measurements and satellite imagery.
Weather forecasts and past weather come from Weather data by Open-Meteo.com, used under the CC BY 4.0 licence.
How a household's use varies through the day and the year comes from Elexon's daily profile data for homes. Contains BSC information licensed under the BSC Open Data Licence.

9. Ending the Service

You can stop using the Service and delete your account at any time. We may suspend or end an account that breaches these terms, or discontinue the Service with reasonable notice.

10. Changes to these terms

We may update these terms from time to time. If we make a material change, we'll let you know via the app or by email before it takes effect.

11. Governing law

These terms are governed by the law of England & Wales, and any dispute will be handled by the courts of England & Wales.

12. Contact

Questions about these terms? Get in touch.