Battery Powering ESP Devices

Looking to make a Lux light sensor as my first ESPHome project through HA. I've bought ESP8266 boards and BH1750 light sensors. My question is how do I power them? I really want them to be scattered around the yard for best placement of future solar, but everything I'm reading says that battery power these wifi devices will not work out well. I've got no power to the backyard (in the USA) so at a loss for how to power these things when they are deployed.

I've read that LifePo4 AA sized batteries work well for an ESP8266 but before I dump even more money into this project, curious what others use for power?