I haven't installed Home Assistant but I have openhab and the gateway running on the same raspberry pi.

HA should't be any different.

Hi @CrankyCoder ,

I think that 18650 will have plenty of juice for a project like this one.

Do you have an idea on how much does the water sensor consume in sleep mode? I am curious and I might actually go for the same project.

Which one are you using?

Hi CrankyCoder,

I have door/window sensors running using interruptions. I got rid of the regulator and the power led and I am using a step up converter to take as much juice as possible from the batteries. The oldest node has been running for a year already on 2 AA batteries so your project is definitely doable.

The problem could be in case the leak sensor throws a lot of false positives in which case it would drain the battery quicker.

I hope it helps.

--
David
[http://www.smarthomeblog.net]