This is almost exactly my question but I'll be a little more specific. I want to guarantee that no data about my usage leaves my network. You mention local integrations, is there a formal commitment to opening up the platform to opensource local servers? Similarly, what about always providing functionality without sending usage data?

Internet's not required, and we're aiming to pack as much offline functionality in as possible. This includes an MQTT based local API (WiFi) and ability to directly tether the phone app to the device over WiFi. Certain app features like historical usage and utility data integrations may not be available if the device isn't internet connected though, just to be transparent.

Why not buy a UPS?

I don't think the intended use-case is servers. The products they list are appliances and less critical electronics.

It has a 20 ms switch-over to battery backup. APC UPS' range from 2 - 6 ms.

There is a StackOverflow answer that says the upper limit for servers is 25 ms but 20 ms might be cutting it fine.

https://serverfault.com/questions/564156/what-is-the-interru...