btu question

I have tried the search option but didn't get a good answer so here it is. Forgive me if it has been answered many times before.
What is the minimum BTU's I can get by with in AG brewing? I am going to use keggles brewing 5 gallon batches. Can I get by using a 30,000 BTU burner for now?
I found a deal on a 2 burner Camp Chef cook stove for $79. It has 2 30,000 BTU burners I like it because of the framework and wind screens. The keggles sit good on it and it is well made for the price. My only concern is if the btu's are a little lacking. The legs are detachable and I intend to use it on a tabletop with the 6" legs only. 2 kegs sit on it perfectly. What do you think?

To drastically increase the btu rating on any burner, buy an adjustable regulator. One of those things I wish I bought years ago. I can shoot a flame 10 feet high out of my piece of shiit burners if I want to.

Here's the math:

It takes 1176.8 BTUs to bring 1 gallon of water to boil in 1 hour.

I would want to get to boil in about 30 minutes at 6 gallons for homebrew purposes, which would take 14121.6 BTUs at 100% efficiency.

You obviously aren't going to get 100% efficiency (i.e., 100% of the BTUs from the burner converting to 100% heat in the water), but 30,000 BTUs should be able to get you up to mash temps and boiling temps in under 30 minutes each.

My burner is 55,000 BTUs, and I get to mash temps in about 18 minutes and boil in about 14 minutes from mash temps.

I appreciate the input. I will give it a try and if not happy, I still have a nice camp stove :^)

I tried the burner last night, put a keg on one of the burners and added 8 gallons of water. It took 30 minutes to bring it up to 170* and 55 minutes to bring it up to boiling. It will have to do, I am not going to buy another burner right now. I like the size of the frame, but it will be slow. However, I have time to kill and not much else.
I have yet to brew an AG but I am going to attempt it tomorrow, if things go right (like thats gonna happen). So far, I have bought ($40 each) and converted two 15 gallon kegs, one for a HLT with a valve, thermometer and sight glass, one for a boil kettle with a drain valve. Also purchased a 10 gal igloo round cooler on the cheap ($15) which I have built a MLT with a manifold and valve. This will be a gravity flo system until I get a pump rigged up.
I have recipe and ingrediants for something called Golden Monkey Ale and will try for a brewday tomorrow. My biggest concern is I am still without a wort cooler and will try to get by with using an ice bath in the deep outside sink.
I have brewed extract for over 10 years and know that what ever, it will still be beer and hopefully drinkable. I am not going to worry about efficency numbers right now, just hope to hit correct OG (1.052) and brewpot volume, the rest will come later with a little experiance. Am reall looking foward to this.