Jesus, I've been quoting a 1 terawatt figure when arguing with people about how bad our interconnection queues are. It's at 2.6?! That's fucking brutal.
The market is rejecting fossil fuels. Solar is just way, way, way cheaper and wind is substantially comparable (wind at $32/MW-hour, compared to somewhere between $5-30/MW-hour for natural gas depending on the region) And in my opinion, wind still hasn't really hit its learning curve. I expect it's prices will have a plummet in my lifetime, as soon as places like northern Europe, New England, and the dust bowl states start seriously buying it.
If the grid operators were on their shit, we'd be shutting down natural gas plants in favor of renewables for purely economic reason, as already basically happened with coal for gas.
We aren't even talking about having to add new transmission routes. A lot of the upgrades needed are just smart sensors so that we can run lines closer to their real capacity rather than keeping them at enormous factors of safety in fear of very rare events. A lot of the upgrades needed are just reconductoring, which is only a small fraction the price of new routes. If the utility monopolies aren't stepping up to the plate, it's time to get a new contract.