Futurology

Rough calculations suggest that, on current trends, adding 12 hours of storage to the entire US grid would cost around $500 billion and pay for itself within a few years. By contrast, upgrading the US transmission grid could cost $7 trillion over 20 years.

Counterintuitively, electricity cables under the North Atlantic might be much more economical. It would not have the eminent domain and construction complexities of upgrading the US continental land grid. If this cost estimate is accurate, it may be much cheaper.

Is it really much more secure though? Wouldn't one well-placed underwater bomb knock it out of action for weeks or months?

If security was your top priority, surely decentralized microgrids with widely dispersed battery grid storage would be much more effective?