On-topic, since the price and availability of fuel affects boating.

I've been reading about alternative energy sources lately, including solar,
wind, geothermal, etc. All have levels of promise but none will come close
to satisfying energy needs in the short or long term.

Meanwhile, the US has the world's largest supply of coal in various forms.
Coal can be processed into oil. It's called "synthetic oil" because it's
not liquid in it's natural state but when processed, it is virtually
indistinguishable from high grade oil.

Estimates vary, but it is believed that there is at least an 80 year supply
of oil obtainable from coal if it supplied all of our energy needs at
current rates. It would last much longer when supplemented by conventional
oil reserves, solar and wind energy.

The process to convert coal to oil becomes economically justified when
regular oil prices exceed $35 per barrel.
China is busy building several coal to oil conversion plants.

Why isn't this technology and resource being tapped into in the US?

Eisboch