@mlanger
Yes, propane! Most #narrowboats have #propane #cookers. It can also be used for #heating. Alde is probably the leading brand for producing #propane boilers for boats that will run radiators as a #domestic #boiler will.

#Diesel #heaters are also popular. Eberspacher and Webasto being the main brands though many fit very competitively priced Chinese units, but I read somewhere that they are not approved for marine use and should they start a fire insurance would be invalid.

A few #liveaboard boaters have larger Aga or Rayburn oil or solid fuel fired cookers that will also drive radiators

I referred to #cooker rather than #stove deliberately. Almost all privately owned narrow boats have small traditional style #solidfuel
(wood/coal) stoves fitted. On 19th century #boats theses would have been used both for heating and cooking. On modern boats they are usually stand alone heaters in the saloon, but some will be fitted with boilers and drive radiators elsewhere on the boat.