@rfontaine thanks you very much for help. The load of the relay is 100ma 24 volts. Is a selenoid.
I was think make this with pycom with lora. What do you think about ?
About solar power. I was think use a 20W x 24V panel with charge regulator and 2 battery of 5 amps.
Also I have to use some power supply to down the voltage from 24 volts to ncd voltage support.
All this have a cost of 95 dollars in my country.
Do you have a better idea?
https://panelsolarchile.cl/shop/paneles-solares/panel-solar-20w/
https://panelsolarchile.cl/shop/destacados/regulador-de-carga-10a/
https://panelsolarchile.cl/shop/baterias/bateria-agm-5ah-12v-haze/