Terms of Service
These terms are the agreement between you and Sundial (“Sundial,” “we,” or “us”) for the Sundial app, the SundialEV.com website, and related services (together, the “Service”). By creating an account or using the Service, you agree to them. If you don’t agree, please don’t use the Service.
1. What Sundial does
Sundial is a smart-charging assistant for electric vehicles. It looks at your solar production, home battery, and electricity situation and adjusts when and how fast your EV charges, so that more of that charging comes from your own energy instead of the grid. To do this, Sundial connects to your vehicle and energy accounts with your permission and sends charging instructions on your behalf. Sundial is a convenience and optimization tool — it is not an electrician, an energy provider, or a safety system.
2. Eligibility and your account
You must be at least 18 and able to enter a binding agreement to use Sundial. You sign in through a supported provider (such as Google) and are responsible for keeping that login secure. You’re responsible for activity under your account and for making sure the information you give us is accurate. Tell us promptly if you believe your account has been used without your permission.
3. Connecting your vehicle and energy accounts
Sundial only works once you connect third-party accounts — for example your Tesla account and your solar or battery system. By connecting them, you authorize Sundial to access the data those services make available and, where applicable, to send commands such as starting, stopping, or adjusting charging. You can disconnect any integration at any time from the app or from the provider’s own settings; doing so stops Sundial from optimizing that device. Your use of each connected service remains subject to that provider’s own terms.
4. Sundial fails open — keep a backstop
Sundial is an optimization layer, not a critical control system, and we built it to fail in the direction of charging. If Sundial is unavailable, hits an error, or loses its connection to your vehicle or energy hardware, it will not block or cancel charging that would otherwise happen — it “fails open.” The only thing you lose during an outage is optimization: your vehicle simply charges on its own settings rather than Sundial’s solar-aware plan.
Because software and third-party APIs can and do go down, we strongly recommend you keep your vehicle’s built-in scheduled charging configured as a backstop. That way your car still charges when you need it, with no surprises, even if Sundial is offline. Please don’t treat Sundial as your only way of making sure the car is charged.
5. No guarantee of savings or results
We built Sundial to help you use more of your own energy and spend less, and for many people it does. But actual results depend on things outside our control — your hardware, your solar output, the weather, your utility’s rates and rules, your driving needs, and the accuracy of the data third parties provide. We don’t promise any specific amount of savings, and the figures shown in the app are estimates.
6. Plans and billing
Sundial is currently free to use, with no payment details required and no charges of any kind. If we offer optional paid features in the future, any purchase will be made through the app store you installed Sundial from, and we’ll show the price and terms before you buy. We don’t sell subscriptions or charge for features outside of those app-store purchases.
7. Acceptable use
Please use Sundial for its intended purpose and in a lawful way. Don’t try to break, overload, reverse-engineer, or gain unauthorized access to the Service; don’t use it to reach accounts or devices that aren’t yours; and don’t use it in any way that violates the terms of the vehicle, energy, or other providers we connect to.
8. Third-party services
Sundial depends on services run by others — including Tesla, Enphase, Google, and Anthropic (Claude) — to function. We don’t control those services, we’re not responsible for their availability or actions, and changes they make may affect what Sundial can do. Your relationship with each of them is governed by their own terms and policies.
9. The Service is provided “as is”
The Service is provided on an “as is” and “as available” basis, without warranties of any kind, express or implied, including any implied warranties of merchantability, fitness for a particular purpose, or non-infringement. We don’t warrant that the Service will be uninterrupted, error-free, or able to control your vehicle or hardware at any given moment.
10. Limitation of liability
To the fullest extent allowed by law, Sundial and the people who build it won’t be liable for any indirect, incidental, special, or consequential damages, or for lost savings, lost energy, or the cost of substitute charging, arising out of your use of (or inability to use) the Service. To the extent we are ever found liable, our total liability is limited to the amount you paid us for the Service in the twelve months before the claim, or USD $100 if you’re on the free tier.
11. Changes and termination
We may update the Service and these terms as Sundial evolves. If we make a material change to these terms, we’ll take reasonable steps to let you know; continuing to use the Service afterward means you accept the change. You can stop using Sundial and delete your account at any time, and we may suspend or end access if these terms are violated or if we discontinue the Service.
12. Governing law
These terms are governed by the laws of the State of California, without regard to its conflict-of-laws rules. You agree that courts located in California are the proper venue for any dispute that isn’t resolved informally first.
13. Contact
Questions about these terms? Reach us at sundialev@gmail.com. See also our Privacy Policy.