To be fair, there were nations like France which had largely carbon neutral grids 50 years ago, even if this sort of solar and wind only really started their modern style large scale deployments 20 to 25 years ago.
Also, while Carter may not have had them, decently effective solar cells did exist 50 years ago, which is why they were powering nearly all spacecraft and such, they just weren’t cheap.
To be fair, there were nations like France which had largely carbon neutral grids 50 years ago, even if this sort of solar and wind only really started their modern style large scale deployments 20 to 25 years ago.
Also, while Carter may not have had them, decently effective solar cells did exist 50 years ago, which is why they were powering nearly all spacecraft and such, they just weren’t cheap.