Thursday, November 28, 2013

Indoor Electric Brew In A Bag Brewroom

A few months from now I will be installing a 220 volt recirculating infusion mash system (RIMS) in my new brewroom, I've already said goodbye to my old natural gas powered system. My previous brewroom was awesome I brewed over 100 batches in there, it was located indoors in a well ventilated basement and was powered by two natural gas burners. For me at the time this was a really beautiful setup, after some initial trial and error in the layout, it became a very efficient brewroom that was a lot of fun to use. The brewroom was big, it included enough space for a yeast lab, storage area, beer conditioning and an awesome brewing setup. I brewed on that all grain setup for three years and produced some of the greatest tasting beers ever. I looked forward to my time brewing there and inviting fellow brewers over to share recipes, beers, new ideas and to lend a hand from time to time. 

High Gravity Electric Brew In A Bag
Being only months away from moving into the new place I decided that building my next brewroom around an electric brewing system would be the best way go. I'll admit at first I had no idea exactly what the pros and cons of using electric were versus gas powered brewing systems. I soon found myself doing a ton of research to learn everything I could about the electric option and it's benefits over gas. Understanding the power line size was pretty straightforward, there's a lot of useful information on the manufacturer websites to help with that and other concepts. 

A dedicated 220 volt 30 amp GFIC is used to power a 4 wire 30 amp receptacle located near the brewing area and as with any indoor brewroom setup adequate ventilation is an absolute necessity. With electric brewing though we only need to exhaust boil vapors and brewing aromas to maintain a safe and comfortable working environment. Unlike gas powered systems electric brewing systems don't consume oxygen and they don't produce poisonous carbon monoxide so there's no need to worry about exhausting poisonous fumes too. There are other things to consider when comparing electric verses gas like the lower installation cost of a 30 amp 220 volt electric line compared to installing a gas line to power the brewing system.

Indoor brewrooms powered by gas burners have to be well ventilated to quickly remove poisonous combustion gases and replace them with fresh makeup air. As the volume of air required to maintain a safe and healthy brewroom environment gets higher the more cubic feet per minute (CFM) of fresh air the exhaust system will need to remove and replace. In my gas powered brewroom I used two 7,000 btu gas burners to heat the mash and boil the wort for a combined rating of 14,000 btus. 

Using the same cfm calculations published by John Blichmann in BYO Magazine for their November 2012 issue the 14,000 btus created by the gas burners divided by 30 require approximately 450 cubic feet per minute of make up air to change the air in the brew room. The electric powered brewroom will measure approximately 20 feet by 20 feet by 10 feet high and hold nearly 4,000 cubic feet of space. When 4,000 cubic feet is multiplied by the 8 air changes per hour it comes out to 32,000, then further dividing 32,000 by 60 produced the 533 CFM needed to change the brewroom air about 8 times every hour.

Room Dimension Change Room Air
Length   Feet Every  Minutes
Width   Feet Size   Cubic Ft.
Height   Feet

As far as heating efficiency goes a gas burner loses about 50% of it's BTU rating because the heat produced by the flame rapidly radiates outward and away from the wort in the brew kettle. Electric powered kettles are 100% efficient because the heating elements are in contact with the wort at all times. Due to these major differences in heating efficiencies an electric heating element rated at 5,000 watts is capable of heating wort at the same rate as an 18,000 BTU gas burner. The standard calculation used to convert watts to BTUs per hour is to take the wattage of an electric heating element and times it by 3.412, the answer represents the number of BTUs. (Example: A 220 volt 5,000 watt heating element times 3.412 converts to 18,766 btus per hour.)

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