is geothermal energy renewable
Yes and no geothermal energy is renewable source of energy when created from natural sources of energy. Geothermal energy is non-renewable source of energy when its created from man made resources from power plant etc.
Depending on how geothermal energy is create, it could be renewable source of energy or non-renewable source of energy.
There is a fixed amount of energy available as geothermal energy, in the same way that the sun's energy is finite. But another several billion years store of energy is pretty good.