I was looking all over the interwebs for a study comparing different propane burners and their efficiency, but have been unable to find anything. Does such a study exist? I’ve seen an article saying all propane burners get roughly 20% efficiency, but nothing more than that.
What do they mean by efficiency? The amount of heat generated vs the amount actually transferred to the kettle/contents? That’d be dependent on kettle geometry, things like wind, distance from the burner to the kettle bottom, etc. Not sure you can make a blanket statement, but I suppose 20% might be ballpark. You certainly don’t have the surface area and protected environment of a high efficiency water heater.
Why are you even interested in this? Seems like all burners have the potential to completely and cleanly combust propane when set and operated properly. So it really comes down to how many BTUs you need to bring the water to boil in the amount of time you can live with. My own two cents is that a smaller burner is likely to be slightly more efficient since you aren’t blowing so much of your heat off the sides of the pot. But maybe it doesn’t work that way. What do you think?
That’s kind of what I was thinking. Why spend money on a bigger burner if it’s going to go though more propane in the long run, but I suppose time is money if you have to bring 10 gallons to a boil.
The size of the bottom of the kettle is one of the more important factors in efficiency, generous windscreens (or brewing in a garage) is another. The longer you can keep the hottest gasses of the flame in contact with the kettle of wort the better.
[quote=“gerald_weigel”]but I suppose time is money if you have to bring 10 gallons to a boil.[/quote]Yep. I have a 210K burner and it still takes more time that I want to get 20+ gallons boiling.
It takes a while for 12 gallons of wort to boil even with a banjo burner with 210K BTUs; but it is better than a smaller burner.
My original thought was something along the lines of figuring out which burner design is more efficient. Though there’s more to a stove than just the burner. I was just wondering if anyone had done any kind of scientific study of the subject using the same kettle, the same stand, the same volume of water, the same windscreen, the same pressure, and the same distance from burner to kettle. The only variable would be the burner. It should be a simple matter of weighing the propane used and figuring which burner used less to bring the water to a boil.
Though some kind of burner rating could be had if you factored in the time taken to get there. Just a thought.
It’d only apply to that kettle though, you couldn’t really extrapolate. I have a wide 20gal kettle so I suppose it is able to soak up a fair amount of the heat, although a keggle has that lip and a mild curve that I think traps heat nicely. Also I am not sure that the majority of the heat transfer might not be right where the flame itself impinges on the metal, and the heat rolling off the sides may have limited benefit. If you ever see the bottom of a kettle coming to boil you only see the bubbles right where the flame is.
In general I’d say a smaller burner will always win the efficiency race you’re suggesting (amount of propane). The time race to boil is going to be wone by the bigger burners though, and thats what a lot of people are more concerned about. It can take close to an hour to bring 15+gal of warm wort to a boil with a small burner.
Its the same kind of tradeoff as what you consider when using an IC. You can run water slowly and cool with a minimum of water, or you can run it fast and cool more quickly with a larger amount of water.
Interesting question to ask though, I’ve been considering upgrading my burner and have really been wondering what I want to go to. I’m scared of the high pressure burners because of the tendency of the tanks to freeze up, and the money for extra gas from a high BTU burner can really add up.
Yea the problem with any kind of baseline test will be that there is an almost infinite combination of kettles and burner stands. It’d still be nice to have some kind of number other than BTU though. Something along the lines of propane use time and total time to boil X gallons of water.
It won’t be scientific per se, but I recently converted to the SQ14 from using an old Kajun Kooker 200k BTU burner for many years. Aside from the fact I purchased the new burner because it generates absolutely no soot whatsoever on my kettle, I already suspect it is much more efficient than its predecessor and I will get more 5G batches out of it per tank. I have started with a fresh tank and am keeping track of brews. Sure there are some variables but it will be a fair real life comparison since mash times, boil times, and OG are all relative. I really think Mr. Sawyer has it covered: time versus efficiency. GTO versus Prius…
I don’t even use my little turkey fryer burner on full blast. And I do drive a Prius (its the wife’s).
I never ran my kajun kooker full tilt either, but I still think I will eak out more brews on the SQ14 per tank. Although that kooker is loud and the flame is big I think the bright blue flames of the SQ14 are hotter.
No diss on the prius. My example was just an example of a lousy efficient car to a greatly efficient one in relation to speed.
IMO, having a large kettle volume and good wind screening is more important than how efficiently the burner turns propane into BTUs.
My recommendation to any home brewers in the planning stages of pulling together a home brew system with an eye to making it as fuel efficient as possible it to put more focus on the kettle than the burner.
Since I am electric I have my burner in the kettle, so the wind is not an issue. I apparently don’t have any wind in my basement anyway…