I am curious about finding yer brew system efficiency. Buddy I brew with was saying he figures his from the mash-tun to the BK. How he does that, I can’t explain. I say it comes from knowing the amount of sugar potential from the total grain and liquid volume then to what you actually end up with. Any other thoughts or way to figure? Sneezles61

I just plug the numbers into an online calculator.

Here’s my understanding:

- I add up all the extract potential of all grains used. The ppg (points per gallon) is listed for each grain. Just do the math to account for amounts of grains used. Example, let’s say I calculate 400 potential gravity points.

Then after my sparge, as the boil is starting, I measure SG and do the math to account for volume in BK. Let’s say it’s 1.045 (45 gravity points) in 7 gallons. 45x7= 315 gravity points total. 315/400 = 78.7% mash efficiency.

That’s the only one I look at. If it’s low, then I know I’ll either have to boil longer, or add some DME. I do take that preboil SG & volume and use that to figure out my postboil SG, so I can figure out how much DME to add to hit my predicted OG. To continue the example, if I plan on having 5.5G postboil, then 315/5.5= 57 or 1.057 OG.

Rereading this, it’s looks a little confusing to me, but I’m not sure how to rephrase it. Hope this doesn’t muddle things up…

@jimrmaine’s description is good. It may not be a quick read, but if one chooses to read it carefully, it is understandable.

Palmer (**How to Brew**, “Calculating Your Efficiency”) also describes how to calculate the efficiency of the mashing step.

I’m not very good at PC stuff, so I do the math myself and get very close. I was trying to get some idea ifn there was another way. I’m not trying to call out brew friend, I was thinking, theres more than one way to calc. efficiency, I think. I do enjoy when you other brewers weigh in with how you do what you do! You’re all great! Sneezles61

As I looked over the calculations it appears that having gravity points is what makes the calculations “simple enough”.

I’m still hoping for a quick approximation calculation (like this for BRIX to SG and this for adjusting OG).