[GpsFrontier]

With this I would be really really careful. This sounds to me like a big fire hazard

Yes it could be especially when left unattended. I will take care to insure it will be safe from fire as well as the plants.

Kero does burn relatively cleanly but it still has particulate in its smoke. It will over time build up on the inside of you tents. Also I would be concerned about contamination of your fruit. Kero has a very strong very unpleasant taste and when burnt some of the kero goes up in the smoke unburnt meaning it will coat the plants and the fruit and it's not particularly easy to wash off

I was told it was a clean burning fuel but I think they were talking about in the kerosene heaters. I have researched the heaters and they use Catalytic Converters (like in your automobiles exhaust system). Catalytic Converters use a chemical reaction between platinum and the unburnt fuel to create heat, this heat burns anymore unburnt fuel. The more fuel the converter gets the hotter it gets. In the case of automobile converters they usually get red hot inside and have been known to cause car fires when they get clogged (from cars that are not tuned properly).

I am unsure as to how much fuel is left in the kerosene heaters for the Catalytic Converters to react to. Although Catalytic Converters are not something you can build, and are too expensive (at least for autos) to use in a homemade burner. The smallest kerosene heaters I have found so far are 10,000 BTU's and run about $100. That's odd because the 40,000 BTU heater at Home Depot was $129.99, I'll bet that's because of the Catalytic Converter though. 10,000 BTU's is still way to much for my needs. I'm looking into other fuels also like lamp oil. Though so far I am not sure what the differences are. Here is a statement I have found on the subject:

"Lamp oil is a liquid petroleum product that is designed to burn cleanly in brass and glass oil lamps, torches and lanterns. In the same family as kerosene, lamp oil has been further processed and refined so that it doesn't produce as much harmful smoke, soot and other pollutants. Lamp oil can be used for everything from emergency indoor lighting during a blackout to soothing lamp light for a summer evening's barbecue."

I will also look into what the farming industry uses in orchards when the threat of frost is near, although I am pretty sure they use the kerosene heaters. I am also looking into using Propane. I know Propane burns clean by itself and may be a really good option.

I would be more tempted to look at heat lamps or electrical heating before burning something

Unfortunately, these are not options for me. The cost of running these all night would be way too high for me to be able to consider them in anything other than a one night emergency. Small space heaters and small hand held hair dryers also would use way too much electricity to consider. Basically I cant use anything electrical.

There are too many variables for me to get into exactly how I will create the heaters until their done. I can tell you that they will be made fireproof. Also designed so they cant be knocked over by wind or something the wind knocks onto it. They will be wind proof, so the heavy winds wont be able to blow it out. They will also be directional, aiming the heat upward and allowing fresh air in without letting it be blown out. At the same time being defused to spread the heat out so it wont burn the plants as the warm air rises. They don't need to be big, basally nothing more than something the size of a few Tiki Torches is needed. The plastic sheets will never be able to get close enough to even melt much less burn. They will also roll up and out of the way during the day.