Yes, electricity still costs companies money so at a base level they are incentivized to minimize its usage, and then on-top of that carbon taxes should be helping to cover the environmental and incentive costs for further energy reducing innovations.
If you just want to ban electricity consuming industries I don't know why you'd start with AI, which is brand new and has genuine useful value to society, and not say, something like advertising which is just an economic distortion and massive drain on society.