That report only lists, as it's title suggests: "Direct Federal Financial Interventions and Subsidies in Energy".

Harvard Medical School estimates that coal costs the US half a trillion (yes, trillion) dollars every year in externalities that the public, not the coal industry, or the utilities, pay the price for. The total accounted for in your document, for all energy types is only $40 billion, more than a factor of ten less.

You can have a fascinating semantic discussion about whether those half a trillion dollars, every single year, are a subsidy or not, but either way they're getting paid by the US public when a bit more "sudsidy" for solar could have avoided them.

The post I was replying to was discussing only direct subsidies, not externalities. The report I referenced is the one the poster's reference referenced. I don't see how an HMS report on the cost of externalities is appropriate to the discussion, considering the worldwide costs are certainly in the trillions if not tens of trillions.

I'm not sure I'm parsing this correctly, are you saying that the cost of coal externalities are irrelevant to this discussion, because they total trillions of dollars globally each year?

Taking that as gospel, in a supposed 'free market' economy why does the US subsidize fossil fuels all? Does anyone have a compelling reason? Isn't absorbing the cost of the externalities enough?

Likely because the grid is important enough to the economy that there should be government support of the stability of the energy supply.