Need to increase AG capacity and need sugggestions

[EtchyLives]

Short story: I need to increase my ability to mash and boil from 5 gallons to 10 gallons/day. Looking at a small grain bill of 18 pounds of grain per batch.

Current equipment:
15g Kettle
10g Cooler Mash tun
1 Burner

Proposed equipment upgrades
15g brew kettle +1
Burner +1
This way I can start the mash on the 2nd 5gal batch while boiling the first

-or-

10g Cooler Mash tun +1
20g pot
This way I can mash in two mash tuns, combine the wort, and boil a 10g batch all at once

Which would you do? Is there a better way? Can you effectively mash 18 pounds of grain in a 10g Cooler Mash tun with decent (65%)efficiency (which means I would only have to buy a 20g pot.)?

Thanks.
edit: I *think* my current mash tun can hold 18pounds of grain AND mash at 1.5qts/pound.

Each pound of grain = about .1g of volume so that means the grain takes up 1.8g, add 6.75gallons of mash water and that comes out to 8.55g total volume... which is plenty of room to mash. Someone check my logic, and my math, please.

 

[DeBrewer]

What pre-boil volume are you attempting to boil? I am questioning why you cannot use your current 15g pot. Even if you were boiling off 2 gallons per hour, that still leaves you 3 gallons of initial head room. Maybe you are actually collecting more than that to compensate for loss? I have done multiple 10 gallon batches in my old 15 gallon kettles. Obviously you have to manage your break to stymie boil over. As long as your are not boiling too much, you should be able to just upgrade your cooler... Should be the cheapest/easiest accommodation anyway. Maybe I missed something?

 

[EtchyLives]

Thanks for your comment. I just realized that I was doubling my batch size for the 5 gallon boil - to include the wort to be boiled off. Which means you are correct and I don't need a bigger boil kettle. And since my mashtun has enough room to probably mash at 1.75qt/lb and definitely mash at 1.5qt/lb then I don't actually need any new equipment.

Thanks for the input.

 

[rmyurick]

You could go all the way down to 1 qt/lb.

 

[kh54s10]

I have mashed 23 pounds in my 10 gallon cooler. (for a high gravity 5 gallon batch) I have not tried a 10 gallon batch, nor do I want 10 gallons of one style.

I have a 10 gallon HLT on a turkey fryer, a 10 gallon MT and a 10 gallon BK. If I do back to back brews I start the second mash when the first is in the BK. It makes for a long brewday........

If anything you need a bigger mash tun. Your BK should be fine for 10 gallons.

 

[EtchyLives]

Thanks all. I prefer to mash at 1.5qt/lb or higher due to efficiency. Since this is a smaller beer (1.050) I can do the mash in my current setup with no problems. Normally I don't want more than 5gal of a particular style but I'm brewing up a couple big batches for a work party.

Y'all rock with the helpful responses.