I think there should be many prices for carbon.
1) A price to remove the carbon from the atmosphere, based on the current price including everything in the process, mining, making... plus an economic multiplier x2 or x3
2) A price for the consumer which should be above the renewable electricity price to produce the same kwh.
3) A price for the producers, who extract, that one should be higher than the price to remove the carbon from the atmosphere. (It must stay in the ground)
The difference between the sell price and the producer price would go for science, helping the local organic electrical cells to lower the consumer price, extract the carbon from the atmosphere...
Something that does limit the quantity of energy used by each people like taking into account the ecological footprint that has to be in a perimeter. For example for town of 5000 people, if the average foot print is 3 hectare/person, then the town need 3 x 5000 = 15 000 hectare in the perimeter that it does control.
Because it is difficult and not energy efficient to produce everything on one spot, we could define different zones, one where 80% percent is produced within 10 Km etc...
We have a long way to go...