Thermal Plant

My base is south in safe shallow, just a few meters north of the lava thingy in the south. I was trying to use thermal plants in addition to a bio reactor, but they do not work for long. I constructed it and placed it in the lava with my prawn with the propultion arm. At first it was connected to by base trough the ground, but the next day it was not working. I tried to deconstruct and reconstruct, and it again worked until i logged in again later. I tried to use a power transmitter, but the next day when i logged in, nothing was conected to my base, and the thermal plant had completely vanished. Does anyone know the reason for this or how to fix it?

First time here, but I love the game! Doing my first playthrough on SWITCH, and I'm close to beating the game. Just have to upgrade my Prawn a little more, and explore the Magma Zone, find the Thermal Plant, and beat the game.

Any tips?