Help me Understand Efficiency Calcs

[Brody]

I attached a pdf with the calcs I did for myself to determine efficiency on my last brewday. I can't seem to wrap my head around why using the 2 methods produced different results or how over 100% conversion efficiency could be possible (I'm guessing I have a formula error?)

Would love if you guys could take a quick look and let me know if anything looks way off.

[Roachbrau]

I have no idea how you're doing your calculations. I use metric, so efficiency is really easy. (Volume in Liters * extract plato)/(grain weight kg * potential extract %)

[Bryan R]

[Brody]

Water was definitely on, I didn't measure the grain myself (homebrew shop did) so it's certainly possible it was a bit heavy handed. The one calc put me in the mid 90s the other method 100%+ - but honestly, I'm not sure which is accurate or which is commonly referenced.

I'm attaching the spreadsheet so everything shows in excel if anyones curious about calcs. I'm not ruling out an error in understanding the formulas since this is something I haven't paid much attention too the details of.

[Brody]

Spent some time reviewing and fine tuning the numbers (think some Beer Smith malt specs were off I fixed). Results are similar tho with the method from Kai (http://www.braukaiser.com/wiki/index.ph ... efficiency) yielding a 100%+ result and the points per pound per gallon showing around 95% conversion efficiency.

The disconnect is in the maximum extract - the weight of grist method says the maximum extract is 10.27 plato (~1.041) while the PPG method calculates max as 11 plato (1.044).

Given that my actual pre-boil was 10.5 plato (1.042), and breaking 100% makes no sense (short of decoction at least, heavy handed grain measurement, or a data/calculation error) I'm guessing the PPG method is more accurate? It seems to be what Beer Alchemy and Beer Smith use.

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[Weizenberg]

On a different note, I'd drop the flaked barley . In Germany it's not done.