Wood pellets average 8,000 btu/lb (your values yield 8,850 btu/lb. Close enough for me).

Coal average yield 10,000 btu/lb.

I'd say that is more portable. It requires more technique perhaps than a propane stove, but these skills can be learned.

Looks like I need to go pick up some coal next week.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)