Average price per megawatt hour: $26
2 billion dollars for 531,000 megawatt hours delivered from this sinkhole works out to be $3,800 per megawatt hour.
Seems cheap compared to other solar options.
Clearly, as you have shown, electricity would have to become extremely expensive before solar is compelling. The two technologies might meet in the middle at some point but that would still mean that heating and light ones house would be extremely expensive... and unaffordable.