Use this to understand how different versions of efficiency work. Using any units will
work here as the calculator is working out percentages.
Mash efficiency is how efficiently your mash was converted. This will usually
be calculated from the grains and volumes in your recipe. This is the primary
efficiency figure Brewbat uses in it's recipes.
Brewhouse efficiency is mash efficiency less vessel loss. Unless there is
no vessel loss, this figure will always be lower than mash efficiency.