Fuel for the Mono-tube Boiler Fire

In the context of steamboating it is likely that the question of what to burn in the firebox is very much location based.  In the UK where Welsh Steam coal is a revered product, the answer would normally be coal.  In the US where the woods are extensive the answer would most often be wood.  However, when the focus of the discussion moves to mono-tube boilers most often the expected answer would be oil of some sort or possibly gas.  The logic for answers is that oil and gas are fuels for which it is easy to control the intensity of the fire and, in too many people's imagination, the monotube boiler is very difficult to control.

As is so often the case, this 'common sense' answer is too simplistic. Thus the news that Wally Mounster ran a steam launch with a mono-coil boiler fired with wood caused many a steam boater's jaw to drop.  The reason that he ran it successfully for more than 25 years was that he knew the charateristics of of wood fires, had built an excellent boiler design and used partially automated boiler controls.  Thus the 'take away' from this is that it pays to know what one can expect in terms of how the chosen fuels burns and can be controlled.

In the context of the 2020s, many people's attention is on the growing problem of Climate Breakdown.  Thus burning fuel is considered by many to be an anti-social activity.  However, it helps if steamboating is placed in the wider context of CO2 and other emissions from fuel use.  A day's steaming with a canoe style launch would probably use less wood than might be used by a the wood stove in a medium sized house in one night.  Emissions from driving any distance to a steamboat meet will far exceed the emissions from the boat itself, while the emissions from even a short haul holiday aircraft flight will exceed that by many times. 

Assuming that the steam plant has been designed for solid fuel then thought does need to be given to replacements for coal.  The main reason for that is that coal is becoming increasingly difficult to obtain since mines are closing and public opinion backs the idea of leaving coal in the ground.  Happily, there is quite a large flow of flammable waste that could be used and is being tested by Heritage Railways and others. (see: Lynton & Barnstaple Railway Yellow Coal trial)  (The Winding Road to Yellow Bricks)

On a different page John Emmett explores the issues of using Renewable Fuels for steamboating purposes. On the section below John explores the contentious issue of firebox shapes.  The 'traditional' fire tube and water tube boilers have evolved a general, but not standardised, approach to the firebox.  However, mono-tubes based on coiled pipe, offer the designer a challenge in how to surround the fire by coiled pipe and get one's coal shovel over the grate.