18 billion USD for a fusion reactor.

installed utility solar is right now about $1.50 / watt. The subsidy is 1/3 that. So $0.50 / watt.

$18 billion would incentivize 36 billion watts.

36 GW of fully installed utility solar is about half of all the PV solar installed in the world in 2016.

36GW vs 3GW (iter's 500MW * 6 because the panels provide maybe just 4 hours per day)

I realize fusion may be long term important, so well spent. Just hope people are remembering we've got that big fusion ball in the sky.