For outdoor cooking open fire and many types of portable stoves can be used. The main issues for travellers, beside ease of cooking, are weight and availability of the right type of fuel.
At high altitudes and in cold climates, there is the additional issue about the fuel behaviour in such circumstances: it might not vaporise as expected and thus (or otherwise) not give enough heat.
There are many types of fuel such as:
- gas, often butane, propane or a mixture
- alcohol, often denatured, may contain methanol
- petroleum, diesel et cetera
- metaldehyde or hexamine, sold as tablets
- wood, charcoal, et cetera
Multifuel stoves can use several different fuels, often by changing some parts. They may be confined to an assortment provided by the vendor, check the specifications.
The fuel types typically used differ from region to region, and similar products available for other uses may be less suitable for portable stoves because of additives. This is especially a problem for the liquid petrochemical fuels. Also alcohol for this purpose is hard to get in some regions. Fuels provided by the stove vendor are mostly unavailable unless the stove is common at the destination.
For gas, the worst problem is often getting the right container. As there must not be any leaks, you should use matching connectors or good adapters.
Wood or fuels derived from only mechanically processed wood (i.e. cut or pressed together) is available almost globally, but rather bulky and not a good way to store fuel if space and/or weight are critical and you can't re-stock for a long time (e.g. when on a boat or in remote, barren areas such as a desert)
Solar cookers require no fuel, which makes them particularly useful for long trips without reliable re-supply opportunities. Lightweight panel ovens made from foam or cardboard covered with aluminum foil direct energy from the Sun towards the pot. The pot can be placed inside a clear or thin plastic bag to speed cooking, especially on windy days. The speed of cooking depends on the intensity of sunshine, how well you've positioned the solar cooker, and what you're cooking. Small amounts of smaller pieces (such as diced potatoes) in the minimum amount of water cook faster than large quantities of large pieces (such as whole potatoes). It could take as little as 10 minutes to melt some butter, or up to half a day to cook a couple of bowls of rice in a small panel cooker; thin or small pieces of bread (cupcakes!) fall about halfway between. Even on a freezing cold day, a portable solar cooker can collect enough heat to cook rice or to pasteurize water for drinking or washing, and it's very hard to burn food in them.
Want to come back to something warm, but don't have a solar oven? If you're car-camping, or even just leaving your car in a parking lot for the day, then you may be able to turn it into a solar warming oven. For this approach, it's usually safest (and fastest) if your food is pre-cooked and needs heating rather than cooking. Park your car in the sunshine, place food in an appropriate dish on the dashboard (you may want to put a towel underneath the dish to protect your car from the hot dish), and let the sunlight do the rest. You could come back to hot bread rolls, melted cheese, or re-heated pizza.
Engine block cooking, which is also called "carbecue" after the idea of barbecue grilling, uses hot parts of a vehicle's engine as a heat source for braising meat and vegetables. The food is wrapped and protected in several layers of aluminum foil and secured on a particularly hot metal area of the engine, such as the exhaust manifold, by compressing it slightly with the hood to the engine compartment or attaching it with metal wires. While you drive to your destination, the food cooks by absorbing heat from the engine. The simplest meal is re-heating pre-cooked sausages, which might take about an hour of driving at highway speeds. Larger and more elaborate meals, such as roast with potatoes and other vegetables, can take several hours to cook.
The same fuel may have different names in different countries. Not only does American and British English differ, but trademarks or other secondary names are often used.
As fuels are flammable, taking them on planes, boats, trains and buses is often restricted. Thus being able to use a locally available fuel is a huge benefit. If this is not possible or you need to carry a moderate amount (e.g. to get to a destination without good shopping possibilities), you should check the relevant regulations. Also if travelling with firewood in your vehicle, check regional laws as transporting it over borders is often illegal. Carrying "suspicious" amounts of some flammable materials (however the authorities in charge choose to define that) may also get you selected for intensive questioning or worse in some countries or when travelling in some sensitive areas.
Depending on country and fuel type, fuel may be available e.g. at car fuelling stations, marinas, outdoor shops or countryside grocery stores.
The locally preferred fuel (especially in countries with scruffy or no rural electrification) may often be available even in very out of the way places, at sometimes steeply discounted or very cheap (on a global scale at least) prices. Some research as to whether gas, wood or some other type is usually used and what the common "packaging" is, can go a long way in lowering your spending and raising your chance of finding fuel everywhere you go.
Larger gas cylinders are often with a deposit charge: first purchase is more expensive, but after that you usually swap an empty cylinder for a full one, only paying for the content.
The light portable stoves are best suited for soups and stews. You have no oven (although you can construct substitutes) and the frying pan is not as good as at home. Although dried ready-made meals are often used to save weight and time, cooking fresh food with simple receipts is not much more difficult, and having at least some fresh ingredients makes the food more tasty and healthy. A concern with fresh food is spoilage. If you don't have an opportunity to keep certain products cold for long periods, you should prepare them as soon as possible and don't leave leftovers for more than a day or so.
Wilderness guidebooks often provide a rich selection of delicacies to cook by open fire, including special techniques for baking bread and broiling fish. Some food is regularly prepared at an open fire even by casual campers. Virtually all meals that predate the 20th century can be made over an open fire or with the remaining heat of a fire with skill and creativity - after all, that's how our ancestors did it.
The fuels are flammable and some very toxic.
- Gas leaks are easily fatal. The gases used can cause unconsciousness and death and will burn furiously if mixed with air and exposed to a spark. Check connectors and tubes, always turn the off switches, keep the containers out of sleeping areas and make sure the ventilation is good,
- Petrol (gasoline) will likewise cause a catastrophe if vaporised and exposed to a spark – and vaporisation happens at room temperature.
- Alcohol burns with a sometimes hard to see flame. Many people have tried to refuel the stove while the fuel is still burning (or the stove still hot). The reaction to throw away the bottle may spread burning liquid at the spectators, who may not notice right away that their clothes are burning. Always let the stove cool before refilling.
If using open fire you should always be very careful, both not to cause burning particles to fly away and to extinguish the fire reliably. Have enough water in reach. Also note that most modern outdoor clothes are vulnerable to sparks and fire.
An old scout tradition after extinguishing an open (wood) fire is to leave two small green branches on the site of the fire to prove any fire that might break out in that area wasn't caused by you. Waiting an hour or two after you put out the fire to make sure no smoldering ember remains is a good idea in any case.
In dry or windy conditions the stoves can also cause wildfires.
- Knives are an important part of the cooking equipment