Back in the day, many offshore voyaging pioneers like the Pyes, Smeatons, and Hiscocks cooked on Primus stoves: Peculiar machines that relied on hand pumped air pressure to force kerosene (paraffin) into a burner that was preheated with metholated spirit (industrial alcohol). Tales abounded of flare-ups, singed eyebrows and sea-cooks totally traumatized by the unpredictable behaviour of these machines.
Polaris, the sailboat we looked after for a month in Greenland, is fitted with a three burner kerosene stove from Switzerland-based Bertschi. The fundamental technology is the same as the Primus, but the pressure is provided by an electric pump (with manual backup) and the burners preheated by electric elements (you could still use alcohol if these failed). However, even with this automation, cooking on this machine requires strong nerves, chanting incantations in an obscure Swiss mountain dialect, and the sacrifice of small animals.
The stove does include a small oven, but this requires substantial reconfiguration of the stove to use and there is no grill. Other problems are the smell of burning kerosene, which can turn even the strongest stomach, particularly at sea, and the risk of some quite spectacular, but probably not actually dangerous, flare-ups if the burner is not heated enough before turning on the valve.
When you add to all that the difficulty of controlling the temperature of the elements and the truly eye-popping cost of the machine, you could be forgiven for wondering what the point of going this route is? Well, kerosene has three big advantages over propane as a cooking fuel:
- Its vapors will not pool in the bilge waiting to blow you to kingdom come the way propane can.
- Kerosene can be procured almost anywhere, albeit in varying qualities, with none of the problems of different valve standards that can make getting a propane cylinder filled difficult or impossible, even where that fuel is available. You can even, at a pinch, use aviation jet fuel in a kerosene stove.
- A kerosene tank, like the one on Polaris that takes up no more space than two 20-pound propane bottles, can hold enough fuel for at least a year of cooking.
Will we be fitting Morgan’s Cloud with a Swiss kerosene stove? No, but we can see the point, given the mission that Polaris was built for.
By the way, as we discovered when I was cooking Christmas dinner, an incompletely combusting kerosene burner can produce carbon monoxide just the same as a poorly adjusted propane stove. All boats should be fitted with a CO detector like both Polaris and Morgan’s Cloud are.
Dick December 19, 2009 at 3:52 pm
I would like to nominate CNG stoves/ovens as a good alternative to both kero and propane. Having survived a blowup and burnup on a 75′ ketch as we were leaving New York Harbor for the Med in the late ’60′s due to propane lying in the bilge and the genset lighting it off, CNG that is lighter than air seems to work well. Outside the US it is reasonably easy to obtain also.
Denis December 19, 2009 at 3:53 pm
I fail to see why people continue to use cookers using any fuel other than that which is normally on board the boat in large quantities, diesel. My diesel cooker works well, is controllable and gives no smell. The fuel will not explode and there is enough on board to cook the largest turkey. Unfortunately, the oven is not large enough to take an ox, otherwise there is enough fuel to cook that! The only downside, apart from the cost that seems to apply to the kerosene cooker described in your article, is that it needs at least 12v to start.
MarinaOnMaui November 28, 2012 at 1:07 am
I have had much experience with kerosene. It doesn’t necessarily need 12V but can be primed using a little alcohol. Works reliably once you know how much is needed, is cheap and isn’t dangerous like propane. I grew up on boats and fuel settling in the bilges has always been a rallying cry, which is why I don’t understand why all these modern boats have propane. The convenience isn’t worth it and the cost and bother of filling outside the US is a problem too. I’ve been looking for a boat for over a year, and have resigned myself to the fact that they all have propane now. I will re-fit with one of these Kero stoves when I find the right boat, which is why I have this site bookmarked in my Favorites!
John December 20, 2009 at 3:34 pm
Diesel cookers sound interesting, although the only ones I have ever seen were huge, smelly, heavy, and temperamental. That may have changed.
CNG seemed like it would become the fuel of choice on boats at one point in the eighties but has faded out since. The big drawback with it is that it packs a lot less energy per pound than propane. Also, the bottles are relatively big and heavy because CNG must be stored at very high pressure to remain a liquid. I’m interested that you would say that it is generally available outside of the USA. My understanding, admittedly based on hearsay, is the exact opposite.
While we see the benefits of other fuels for cooking and, as any regular reader of this site knows, we are very concerned about the explosion danger inherent in propane, we can’t see changing from that fuel on Morgan’s Cloud, if for no other reason than the instant and controllable heat ability of a propane cooker. By contrast, as we understand it, all of the liquid fuels, kerosene (paraffin), diesel and alcohol (don’t go there) require a preheat cycle that unacceptably interrupts, at least to us, the rhythm and timing of cooking. But then we are big time food lovers that like to cook quite complicated multi-item meals, often with sauces as well. Doing a John-make-fire act complete with preheating and flare-ups for the three rings and the oven required in the middle of making my pork chops with sherry apricot sauce recipe, would be a sure route to tears!
One alternative that does look interesting, is that of induction and convection electric cooking. Steve and Linda Dashew have been experimenting with this technology and have found that it is so efficient that using it with battery power, through an inverter, is practical. Of course they have huge battery banks on their boats. We have not got into the details of what minimum battery bank and generation capacity is required to make this practical, but it does bear further study.
Marina Batham December 27, 2011 at 8:39 pm
Aloha John, I ‘m interested in the company that built that fine looking kerosene stove you have pictured in this article? They are really hard to find, so if you have any tips on getting one, I’d love to know! Mahalo, Marina
Colin December 28, 2011 at 9:54 am
Hi Marina
As luck would have it I was recently looking for a replacement heater for our yacht, and came across Bertschi. They have a website at http://www.bertschi-petrol.ch complete with English translation.
But I’d agree with everything John says re kerosene as a cooking medium – smell, flare -ups etc. – having owned a boat with a kerosene cooker in the past, albeit it one less sophisticated than the Bertshci range.
Best wishes
Colin
brian March 15, 2012 at 10:21 pm
I had a diesel/kerosene stove on myboats for the 18 years I was cruising around the world. Here my opinion. it burns hotter than propane and one can tune the heat yust fine. preheating must be done the way it has to be done easy clean no problem there are no flare ups at all if you preheat every time with out inventing shortcuts. Maintenance needs to be done as systematically as on your engine . It gives you peace of mind knoving that there is no propane in the bilges . When I was too lazy to clean the burners every two months I would be forced to use the second burner that was standing by. I never ran out of fuel. Never did a taxi refuse to transport me to the propane fill station. And my burners never smelld bad never black smoke no dirty ceiling. Now the disadvantage . the only draw back that diesel/ kerosene stoves have, by the way , pressurized diesel and pressurized kerosene burn in the same stove with the same burners they just need different jets to carburate and diesel needs a little more preheating with the same alkohol. I had a small propane burner in my stoves for quick coffees at anchor but diesel/kerosene for cooking. By the way , I used to coock three times a day very extensivly, no cans, at anchor at sea and also during feavy weather. Propane in heavy weather is useless on a sailboat. It will go out and keep on flowing unburnt. I mean in real heavy weather. U sailed through hurricane Lili and hurricane gilbert , sailing not anchord as we had no cans we had to cook. No nasty smell, we felt safe and the world was a fine place with full stomachs. brian
Jack November 27, 2012 at 10:01 pm
Brian:
What was the brand of stove that you used? Was it small enough for a narrow 38′ sailboat? What type of venting was needed? Was it gimbaled? I want to replace our old CNG stove before we begin passage making and like the density of liquid fuels.
Thanks
Jack