As a more solid data point, Hinkley Point C was built with an inflation-adjusted strike price of 9p / kWh in 2012. That's about 11p / kWh today, or $.13/kWh.

That's not a data point, as it's still under construction. Usually it's best to double the initial cost estimate to get a realistic one.

The strike price is the guaranteed price that British ratepayers and the government have guaranteed Hinckley. (The government will make up the difference if retail prices are lower.)

It’s entirely possible its builders will go belly up and need even more bailing out, but that’s some years away.

> The government will make up the difference if retail prices are lower

… and pocket it if higher, right?

Nope! It’s a price floor.

It's not a price floor [1].

  If the wholesale price of power is higher than the strike price, then the operator pays the difference to the regulator.
  

[1] https://www.jstor.org/stable/pdf/resrep14807.4.pdf