Hi all,
I am running Home Assistant on a laptop I didn’t use anymore. However, this laptop doesn’t have battery, so if the power goes off, the laptop goes off as well (and it happens more than it should).
I wanted a way to turn this laptop on remotely.
I thought on using WoL, but it didn’t work out of the box. I imagine some configuration is required, but I didn’t find anything about it.
Does someone know how to configure it? Or has another idea on how to turn the laptop on remotely?
There might be a setting in the BIOS which tells it to start up automatically when extermal power is connected?
Did you already check out the BIOS of the laptop?
There might be an option somewhere in the BIOS to enable WoL, or an option to auto power on again after a power failure.
Unfortunately, no luck. BIOS doesn’t have any option for WoL or auto power 
WOL only works in local lan, so you’d need another always powered on device to send it.
Using an old laptop may seem cheap, but the extra energy consumed compared to a Raspberry pi will be significant. If you buy a raspberry, you’ll likely earn the cost back after a year of Home Assistant use.
You could always get a UPS. I have mine plugged into one.
I had the same issue. Spent a few bucks ($10?) and got a new battery, so now it has a built-in UPS as we pretty rarely lose power and it’s usually just a flicker anyway.
Are you sure about the auto power?
There are a few different options in a BIOS:
If none of these are available, check if there is a BIOS update which adds any of these features.
Maybe WoL is added too but as stated by @Edwin_D: WoL only works on LAN
If you specify the make/model of the laptop someone will likely be able to tell you if WoLyis is supported and what you need to have for it.
Sure, I am using a Dell Inspiron 14R-5420.