[denny]

If 100% is defined as the most they can give under normal circumstances.

I think the "under normal circumstances" qualifier is bogus.  To me, 100% is all there is.  If you're being chased by a bear, that's where you give 100%.  Under other circumstances, you may be running really fast, but it's not 100%.  Just my curmudgeonly take on it!

[brushvalleybrewer]

To me, 100% is all there is.  If you're being chased by a bear, that's where you give 100%.  Under other circumstances, you may be running really fast, but it's not 100%.  Just my curmudgeonly take on it!

Okay. Let’s work with that. Say we all agree it’s 100% if you’re being chased by a bear.

Now suppose we shoot you out of a cannon… 

[Kaiser]

Denny, in that case the laboratory extract given in the malt sheets is not the 100% mark. And we should not use it as the baseline for efficiency. 

Kai

[tubercle]

To me, 100% is all there is.  If you're being chased by a bear, that's where you give 100%.  Under other circumstances, you may be running really fast, but it's not 100%.  Just my curmudgeonly take on it!

Okay. Let’s work with that. Say we all agree it’s 100% if you’re being chased by a bear.

Now suppose we shoot you out of a cannon… 

 Tubercle gets off the couch and draws another from the kegarator - that's 100%

 Being chased by a bear - might be able to squeeze out another 1%

[hopfenundmalz]

If 100% is defined as the most they can give under normal circumstances.

I think the "under normal circumstances" qualifier is bogus.  To me, 100% is all there is.  If you're being chased by a bear, that's where you give 100%.  Under other circumstances, you may be running really fast, but it's not 100%.  Just my curmudgeonly take on it!

I am with Kai on this.  100% is often a standard rating on engines or electric motors that can be exceded for short periods without damage.

Not beer related, but WWII fighter planes had maximum rating for the engines.  There were also max combat ratings, and the top power rating was emergency power ratings for 5 minutes of operation.  Emergency power broke a tell tale on the throttle, made of piano wire.  The mechanics know there was some serious work to do, or that it was even time for a new engine. 

Kind of like you might outrun the bear, but something is blown out the next day...

[bluesman]

I think the 100% mark is the level to which we as homebrewers can pratically achieve. Anything more than that will require additional resources and steps with which we don't ordinarily undergo. So for all pratical purposes, 100% efficiency for homebrewers is the ultimate goal.

[kerneldustjacket]

 Tubercle gets off the couch and draws another from the kegarator - that's 100%

 Being chased by a bear - might be able to squeeze out another 1%

Can't you mount a tower in one arm of the couch? It would reduce the energy required to obtain a full glass, and therefore improve your efficiency.

Not beer related, but WWII fighter planes had maximum rating for the engines.  There were also max combat ratings, and the top power rating was emergency power ratings for 5 minutes of operation.  Emergency power broke a tell tale on the throttle, made of piano wire.  The mechanics know there was some serious work to do, or that it was even time for a new engine. 

Good analogy Jeff. I remember a book I read as a teen where WWII pilots give their first-hand account of  harrowing or eventful missions; one fighter pilot mentioned the piano wire across the throttle's path...he had to break it to escape a flight of enemy zeros, IIRC.

[oscarvan]

100% is then a limit imposed by the engineers, whereas "war power" or "stuffing it in the radar" is the ACTUAL 100%, ie the maximum the engine will produce under the circumstances. Semantics vs physics.

[denny]

Denny, in that case the laboratory extract given in the malt sheets is not the 100% mark. And we should not use it as the baseline for efficiency. 

Kai

and the thought of that makes my head hurt....wait a minute, maybe that's the hangover! 

[beerocd]

I think the 100% mark is the level to which we as homebrewers can pratically achieve. Anything more than that will require additional resources and steps with which we don't ordinarily undergo. So for all pratical purposes, 100% efficiency for homebrewers is the ultimate goal.

Sounds like 100% is average, the way you put it. Anything less, is due to not enough effort on the brewer's part.
So, the new "C" grade brewer needs to get 100%, anything below is lazy and below average - anything above is due to effort above and beyond (aka: above average effort).

[Mikey]

I think the 100% mark is the level to which we as homebrewers can pratically achieve. Anything more than that will require additional resources and steps with which we don't ordinarily undergo. So for all pratical purposes, 100% efficiency for homebrewers is the ultimate goal.

Sounds like 100% is average, the way you put it. Anything less, is due to not enough effort on the brewer's part.
So, the new "C" grade brewer needs to get 100%, anything below is lazy and below average - anything above is due to effort above and beyond (aka: above average effort).

Well, that puts me in the "lazy and below average" category.

[bluesman]

I think the 100% mark is the level to which we as homebrewers can pratically achieve. Anything more than that will require additional resources and steps with which we don't ordinarily undergo. So for all pratical purposes, 100% efficiency for homebrewers is the ultimate goal.

Sounds like 100% is average, the way you put it. Anything less, is due to not enough effort on the brewer's part.
So, the new "C" grade brewer needs to get 100%, anything below is lazy and below average - anything above is due to effort above and beyond (aka: above average effort).

I need to proof read more often. 

What I really meant to say was that 100% efficiency presumes 100% conversion of available starches (assume 80% extract potential) plus 100% lautering efficiency which is near impossible from a practical standpoint. I'll venture to say that the AVERAGE homebrewer achieves 75% efficiency.

[malzig]

The lauter efficiency of the congress mash does not matter since the extract content is determined from the gravity of the wort and it's mash thickness, which is 8 l/kg.

Thanks, that's good to know.
I've only read the procedure in journal articles, where that detail was never pointed out.  I had assumed, since they were running off the wort through a filter paper, that they were using the volume as well as the gravity.  I hate it when research papers leave such important details out of the method section.

[tubercle]

... I'll venture to say that the AVERAGE homebrewer achieves 75% efficiency.

 Then 75% becomes 100%

[malzig]

What I really meant to say was that 100% efficiency presumes 100% conversion of available starches (assume 80% extract potential) plus 100% lautering efficiency which is near impossible from a practical standpoint. I'll venture to say that the AVERAGE homebrewer achieves 75% efficiency.

Or maybe less, which infers that the average homebrewer either isn't achieving complete conversion, has a tun with a substantial dead volume or suffers grain bed channeling.

Recently I saw a brewer confused when his new tun made his efficiency drop from 80%+ to 65%.  His numbers indicated that his dead volume increased by 1 gallon.