> Also see Figure 19 on page 65, which summarises the different financing options, ranging from 100% state, the actual HPC deal, to 100% private.
Notice how the table of different outcomes shows changes in cost to taxpayers/government, returns, and the strike price. It doesn't show changes to the total construction cost itself, which is presumably fixed no matter what the financing option is. If the grandparent comment was correct, the table would have shown a different construction cost for different financing options.
All that's different is the strike price - which makes sense.
https://www.nao.org.uk/wp-content/uploads/2017/06/Hinkley-Po...
Part 1.18 (page 22):
> "For example, if we assume the government financed the project and required a 2% return (nominal, equivalent to its borrowing cost)..."
Part 2.3 (page 27):
> "The investors expect their return on the project to be 9.04% over the 60-year operating life of HPC."
Also see Figure 19 on page 65, which summarises the different financing options, ranging from 100% state, the actual HPC deal, to 100% private.