> 1. Long distance transmission lines.
Those are really expensive. They're part of the toolbox, but they're not tool #1.
> 2. Some type of "clean, firm, dispatchable" power. Examples include: Nuclear fission, fusion power, deep geothermal, and space based solar power.
If you're relying on that to supply power during those winter weeks without sun & wind then it has to scale up to 100% of power needs. And if it can do that, why build anything else?
To get to 100% carbon free with > 99.99% reliability for under $1T, your primary tool is modelling.
Then you reach for:
- source diversity. Wind is more expensive than solar, but it tends to be highest at dawn/dusk so is a great complement.
- overprovisioning. Enough solar to supply needs on a cloudy winter day
- storage.
- long distance interconnect. There's never been an hour in recorded history where there's no sun or wind somewhere in the continental US.
https://mitpress.mit.edu/9780262545044/electrify/