To explain this just a bit, nuclear power plants have roughly three sections: the reactor containment building (the dome), the turbine/generator building, and the steam condensers with cooling tower. Some steam condensers do not have a cooling tower, such as the Perry Plant on the Lake Erie south shore. That plant used lake water from Lake Erie instead of a cooling tower. I was privileged years ago to tour the Perry Nuclear Power Plant when construction was nearly complete but before the nuclear fuel was brought on-site. Now, though, it has a cooling tower judging from google maps photos of the site. The enviros must have not liked the idea of warm water flowing into the lake.
Nuclear plants also have an area in which spent fuel rods are stored, sometimes this is a pool of water, sometimes a dry storage room. Constructing the building above the condensers, and the cooling tower, and the spent fuel storage area so that they can withstand a direct impact from a large commercial aircraft indicates very thick walls, probably of steel-reinforced concrete, thus adding substantially to the cost of construction.
It would appear from the above that capital costs to comply will add several percent to the already exorbitant costs of a nuclear power plant, perhaps 10 to 20 percent more.
Core cooling capability may include the iconic cooling tower. If those are indeed included, the cost just went way up. Those are typically not very strong; certainly they are strong enough to withstand high winds, but not an impact from a fully loaded 747 or 777, or even an Airbus 380.
So, ratepayers in nuclear-based states bent on building more nukes can now expect to pay another 3 to 6 cents per kwh, on top of the 25 to 30 cents they would have paid before today's ruling.
Roger E. Sowell, Esq. Legal website is here.