What is Specific energy consumption (SEC) per liter of milk?
Specific energy consumption (SEC) per liter of milk is the total energy a dairy plant uses, electrical and thermal, divided by the liters of milk it receives or processes over the same period.
Who tracks SEC
Plant heads, energy managers and sustainability teams in dairy cooperatives and private processors use it to compare sites and product mixes over time. It is a common starting point for dairy energy audits and a natural energy performance indicator for sites working to ISO 50001.
How it is calculated
Divide total energy in a period by milk volume in the same period. Electricity in kWh and boiler fuel, converted to kWh or megajoules by its calorific value, are added together, and the denominator, milk received or milk processed, must stay fixed. Powder, cheese and UHT lines use far more energy per liter than fluid milk, so comparisons are only fair within a similar product mix. Reporting electrical and thermal SEC separately stops a change in boiler fuel from hiding a change in refrigeration.
SEC at line level in Aqueduct
With production volume supplied alongside the line's meters, Aqueduct divides metered electricity and gas for each line by its volume over the same interval, so SEC can be read per pasteurizer, per CIP set or per shift. A weather-normalized baseline built from 6 to 12 months of uploaded utility bills separates summer refrigeration load from genuine drift in efficiency.