Solar can be used to a certain extent. And geo-thermal - that is currently being used in Iceland by Carbfix + Climeworks. Also worth noting that a lot of thes

Solar can be used to a certain extent. And geo-thermal - that is currently being used in Iceland by Carbfix + Climeworks. Also worth noting that a lot of these technologies do thorough lifecycle analysis to make sure that despite the energy usage required they are still carbon negative.