There are still many older boats with pressurized alcohol stoves.
These stoves are very dangerous in my opinion but replacing them with
the newer Origo type unpressurized ones is expensive and the Origo may
not fit the space of the old pressurized stove.
Years ago, I took the burners and rest of the fuel system out of my
pressurized stove and have simply been putting large Sterno cans down
into the burner wells so I can continue to use the stove top. Sterno
is slow. I have been looking at the designs for the so-called "Pepsi-
Can" stoves that burn methanol in a way similar to the unpressurized
Origo stoves but they look more efficient than the Origo stoves if
they are semi-sealed (the so-called "penny stoves").
So, I propose to make an insert for the old unpressurized stoves to
replace the pressurized part but still use the burner wells. It would
consist of an aluminum liner for the burner wells in which there would
be fiberglass to hold fuel for priming. Nesting in this would be a
thin copper "pepsi-can" style stove but insted of a single ring of
flames, I would have an inner ring of flames too for more heat. The
inner ring would get its air from radial indentations in the copper
top.
Next, I still do not like alcohol because its heat content is so low
and the flame is hard to see. So, why not use diesel? Could you get
it to vaporize like alcohol if the thermal conduction was good enough?