Brewery Heat Loads


Sizing a brewery chiller:

Calculate heat load for active fermentation
Fermentation is the process of yeast (Scientific Name Saccharomyces cerevisiae) consuming sugar, and simultaneously producing ethanol (alcohol), CO2(Carbon Dioxide), and SO2(Sulfur Dioxide).

  1. Multiply your total barrels (bbl’s) in active fermentation by 15 bricks
    • Ex: 30bbl x 15 bricks = 450
  2. Multiply 280 BTU’s/brick
    • 450 bricks x 280 btu/brick = 126,000 btu/hr
  3. Divide btu/hr by 70hours
    • If active fermentation is less than 70 hours divide by whatever your fermentation period is
    • If active fermentation is more than 70 hours, divide by 70 hours because that is the time period where most of the heat gain is occurred
    • Ex: 126,000 btu/hr / 70 hours = 1,800 btu/hr in active fermentation

This is the total btu/hr’s needing for active fermentation

crashingbeer copy

Calculate your knock-down load
Knock-down, also referred to as “crashing”, is the process of cooling the hot wort down to around room temperature.  This is typically done through a propylene glycol or water to wort plate heat exchanger.  The heat exchanger has to be rated as a sanitary heat exchanger, as it is touching product.

  1. Determine the worst case total barrels (bbl’s) that you will be crashing at one time
  2. Multiply your total barrels (bbl’s) x 31 (1bbl = 31gallons) to determine your worst case total gallons crashing at one time
    • Ex: 30bbl x 31 gallons = 930 gallons
  3. Multiply your total gallons crashing by 8.5 to determine the total pounds of brew you are crashing
    • Ex: 930 gallons x 8.5lbs/gallon = 7,905 lbs
  4. Multiply your total pounds by your temperature difference for your crash
    • Ex: 7,905 lbs x (68°F – 34°F) = 268,770 total BTU’s
  5. Divide your total BTU’s by the hours your knockdown will occur over
    • Ex: 268,770 BTU’s / 24 hours = 11,198.75 btu/hr

This is the total heat load required for your knockdown process.

Total Heat Load
For your total heat load, WPI tries to assume the worst case scenario in terms of max brewing load.  This allows us to size a chiller that will be able to handle your heat load in the worst possible conditions.  Frequently, a dual circuit chiller system is utilized in order to allow unloading and redundancy.

Add your active fermentation load and your knockdown load to calculate your heat load.

  • Example: 11,198.75 btu/hr in knockdown + 1,800 btu/hr in active fermentation = 12,998.75 btu/hr

It is always recommended to add at least a 25% safety factor in to accommodate for any extra heat that may be added into your process.

There are several other factors that can add to your heat load.  Cold stabilizing loads, wort cooling through heat exchanger (if using your chiller for this step), and cooling down a cold liquor tank (if using your chiller for this step) are some of the additional heat loads that can factor into your TOTAL heat load.  The above sizing is good way to get you started in determining the size of chiller you need.  In the above example, the total heat load is 12,998.75 btu/hr.  It may seem that your brewery would be okay with a 18,000 btu/hr chiller, but there are many other things you need to accommodate for in your chiller sizing.  Your chiller will need to be sized to accommodate that amount of btu/hr at around 28°F leaving glycol.  Something else you need to factor is your glycol percentage. Whaley Products recommends a 45-50% glycol percentage at these temperatures.  All of the aforementioned information will affect your chiller sizing as well as many other things.  Contact the experts at Whaley Products, Inc. to help you size your brewery chiller for your immediate and future brewery plans!
Brewery Process Information:
Brewery Cooling Products
Brewery Glycol Recommendations
Brewery Industry Events
Brewery Clients Served by WPI
Example Brewery Chiller Application
Brewery Heat Load Sizing
Brew-House Control Centers
Brewery Cold Room Cooling