AG Brewhouse Efficiency - What do You Get?

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My AG brewing technique is stove top BIAB in my kitchen, based on an 11 litre pot which is the largest size that will comfortably sit on the electric hob. I normally follow the mash with a sparge, then give the grain a firm but not excessive pressing to extract as much liquor out as I can before the boil and then set the spent grain aside during the boil so that anything remaining that will drain does so, although this usually doesn’t amount to very much. I use about 1:1 mash to sparge liquid volumes, and use pre-crushed grain well within date.
Up until recently I normally brew partial mashes and the DME quantities I use mostly masks grain extraction efficiencies and I usually get just under the predicted OG. However yesterday I did a 10 litre AG only brew and found the OG was noticeably less than I expected and worked out that my brewhouse efficiency was of the order of 67%, compared to the 75% used by the BF calculator. That got me thinking as to what others got. A look through past posts came back with a variety of miscellaneous answers from different AG brewing methods. I know grain is relatively cheap but it you need to be aware of your own typical efficiency if you are going to match a recipe to reality.
So the question is what do others get for brewhouse efficiency on their AG systems, and what do people believe significantly affects it?
 
In my old BIAB system I used to consistently get 65% every single time.

Since I’ve moved to the Brew Devil I’m finding it less consistent whilst I get into a rhythm with it - I’ve done 5 brews in it and had anywhere between 64 (Czech pale lager, so unfortunately one of lowest target SG beers) and 72% (English pale). I expect as I improve my technique it’ll probably level out at about 70%. I think my biggest inconsistency is working out my sparge water and boil off - my last 2 bottling days I’ve got more than 40 bottles out whereas with my old kit I was only getting about 36-37 so my efficiency might actually be better than I thought. Neither of my FVs have accurate volumes on them (one doesn’t have any at all).
 
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Well i've only been back into brewing for two brews now and i'm getting about 56% efficiency. I'm using 3 pots, so a plastic HLT, igloo cooler box mash tun and then a 50L stainless steel pot that i converted for use as the boiler. Weirdly when i checked (using the brewers friend calculators) the conversion efficiency for both brews i was up in the 80% but then the overall efficiency is down at 56%. I've got a big loss to dead space on the boiler and because of that i have to increase the amount of water used and i think that is skewing the overall efficiency. Either way at least its consistent :-)
 
2 pot approach: HLT/kettle -> coolbox -> HLT/kettle.
Mash in coolbox with BIAB bag.
Approx 1:1 mash:sparge. Recently been mashing a little thinner (4-4.5L/kg), which may be difficult in a 11L pot.
60 minute mash, 20 minute batch sparge, both stirred 2 or three times during period. Both squeezed and bag left to drain after sparge.

I was getting unpredictable efficiency 63-74% depending on type of grain and supplier. Bought a cheapo corona-style mill and last 4 brews I have crushed my own grain either from uncrushed or pre-crushed grain run back through the mill. My efficiency has gone up and is far more consistent at 76-78% now.
 
Bought a cheapo corona-style mill and last 4 brews I have crushed my own grain either from uncrushed or pre-crushed grain run back through the mill. My efficiency has gone up and is far more consistent at 76-78% now.
Like this ? Ebay about £22

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I normally get 66% but recently my efficiency has been dropping so I did a few things on my last brew and my efficiency went up to 75%
What did you do to up your efficiency?
 
Yes, one of those mills. It's a shame it's now at £22, mine was £11.39 back in Feb 2020 and looks to be the same one.

It took a little setting up to get the gap right. I kept tightening until I was happy with the crush. For 11L batches that's not too much to grind by hand though you can use an M8 bolt and drive it with a power drill.
 
What did you do to up your efficiency?

A number of things:

* Dough in slowly - Previously I'd just chuck the grain in the mash water in two halve or three thirds (depending on how big the grain bill was) and stir it to buggery with a whisk to break up any dough balls. Now I get my big sports direct mug and put a mug full of grain in at a time then stir the mash. This did mean that I didnt hit my strike temp (I normally use the strike temp calc from jims) and I had to add some more heat to the mash to get it up to strike temp. But on my last brew I just added 2C-3C to the caclulation and it seemed to fix the problem.
Doing this brought me back to 66% efficiency after going well below (about 60%)

* Thinner mash - I've always mashed at 2.5L/kg. On my last mash I mashed at 3L/kg. I think this is what really boosted my efficiency above 66%

* Stirring the mash and sparge - A combination of short mashes and lazyness had meant I wasnt stirring my mash much or at all. I therefore went back to 60min mash and stirring every 20 mins. I normally do a dunk sparge and leave it for 10 mins. I've never stirred my dunk sparge apart from at the start and perhaps at the end. On my last brew I strirred half way through at 5min
 
Just tip the boiler to get the last of the wort out. I usually get every drop by doing this.
I was thinking of doing that or getting one of those dip tubes after a recommendation from someone else on here. That would reduce my deadspace from 6L as it is now down to probably 2L.
 
In the GF I started at circa 65% BHE. Now it is usually over 75%, unless I have some sort of disaster! 77% would be typical with a grain bill around 5.5kg.

Best ideas for increasing efficiency seem to be to dough in thoroughly, give the mash a stir after 30 mins, use around 5kg grain in total (efficiency will only go down with more) and mill your own base malt.
These are in roughly diminishing order of time / convenience effectiveness. Milling your grains is basically for brewing nerds, but it is that sort of a hobby, after all.

Best thing I did was copy DH's painstaking doughing-in which takes around 20 mins. I only stir the mash if it is not going to plan - wort not recirculating well or similar. If it looks OK, leave well alone!
 
* Dough in slowly - Previously I'd just chuck the grain in the mash water in two halve or three thirds (depending on how big the grain bill was) and stir it to buggery with a whisk to break up any dough balls. Now I get my big sports direct mug and put a mug full of grain in at a time then stir the mash. This did mean that I didnt hit my strike temp (I normally use the strike temp calc from jims) and I had to add some more heat to the mash to get it up to strike temp. But on my last brew I just added 2C-3C to the caclulation and it seemed to fix the problem.
I think this is my problem and will try on my next 2 brews, although they are high ABV beers (for me - a 5% witbier and 6.5% saison) so if my efficiency is down it’s less of an issue than with a 4% lager or blonde.
 
Just put my last AG brew through the BF calculator and I hit 72.5% with adjustments to OG measured at 25C, I use an all in one Brewster Beacon.
 
With my system I get between 68-72%, I also mash in slowly not rushing that process I think helps, the controller keeps the water temp steady whilst I mash in, I also recirculate the entire mash length give or take a few breaks when I stir the mash at 15 min intervals.
it's similar to the clawhammer set up, recirculating via a spray nozzle in the lid.
not eff related, but I have noticed a improvement in the clarity of the wort.
 
I think this is my problem and will try on my next 2 brews, although they are high ABV beers (for me - a 5% witbier and 6.5% saison) so if my efficiency is down it’s less of an issue than with a 4% lager or blonde.

It does seem to work. I'm not sure why my efficiency dropped a few brews ago as I do everything the same and have done for years
 
Just tip the boiler to get the last of the wort out. I usually get every drop by doing this.
Trub and all? I keep telling myself “right, next brew I’m gonna throw the whole lot in the FV” then I just get to the last of the clear and think “nah” I always end up leaving a good couple of litres in the Peco!
 
I have never bothered working mine out. I normally get in average 38 bottles out of each brew day. I use biab

For me it's not specifically 'working it out' but on brewmate it has the efficiency as part of the overall software so if I dont hi the OG I'll know I'm under target efficiency and its just a simple matter off toggling efficiency number down to match what OG I got, which works it out for me
 

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