The case of the 4,000 missing hogs – Mystery solved
Watson: My professors neglected to tell me that some people would resent me for what I had learned. So how did you explain your recommendation to their President?
Holmes: Without the math, I explained that the refrigeration system was there to remove excess heat from the freezers and coolers. It also had to remove heat and humidity from people, lights, motors, evening cleaning and sanitation using large quantities of steam and scalding water, and from defrosting the cooling coils. In hot weather it also had to remove the heat that came in through the roof, walls and ventilation.
I told them that Seventy-five percent (75%) of the refrigeration load was for cooling meat. When those live, 300 pound hogs trotted down the ramp from the truck into the room where they were going to get a terrible surprise, their body temperature was about 103 degrees. By law, the temperature of the resulting products had to be down to the cooler and freezer temperature within a fixed number of hours. That’s where the majority of the cooling load came from.
Watson: Did that help them understand?
Holmes: I think so but the natural question still was “why do we run out of cooling on a hot day in the summer”? I think what really convinced them that I might be onto something was the data our system had collected during the winter. Data from a Monday morning at 2 AM when it was minus 20 outside showed the refrigeration system was providing 400 tons of cooling when the cooling load from the plant was zero. This required running more than 600 horsepower (or approximately 600 Kilowatts) of compressors.
Watson: How did you test it?
Holmes: That part was simple. The Assistant Plant Engineer and I went into the plant the next cold weekend. He physically started going to each of the coils and manually closing isolation valves that were in place in the hot gas defrost lines throughout the ammonia system.
Watson: What happened?
Holmes: I sat at the computer screen and watched the electricity from each compressor, the total refrigeration system and the main plant electric meter drop. The refrigeration system started out at 600 KW, then dropped to 500, 400 and on to less than 30 kilowatts. So it wasn’t just a theory; it was physics and physics is always right, 100% of the time.
Watson: How did this help the plant?
Holmes: Well for one thing they avoided spending $100,000 for new electrical transformers and then perhaps, a couple of hundred thousand more for more refrigeration equipment. Avoided costs never show up on the books but they can have a huge impact on profitability.
And repairing the leaking automatic valves on the cooling coils eliminated a 600 kilowatt false load in the refrigeration system which reduced the peak demand by 600 KW and its electrical consumption by 600 KWH every hour of every day of the year. That reduced the plant’s total energy costs by more than $250,000 a year. Assuming that the problem had existed for at least 30 years, those bad valves had cost millions in excessive electrical costs not to mention the pain and suffering of the employees trying to keep everything safe, sanitary and working properly without enough refrigeration during hot summer days. The plant went from running out of cooling to having more than a 100% in reserve on the hottest day of the year.
Watson: Why didn’t someone else catch this problem that had apparently been there for years?
Holmes: I have been asking myself this question for more than 30 years as I have encountered huge problems in buildings, time-after-time. This isn’t an isolated situation. I wish I knew the answer. I do know that in-depth problem solving isn’t the norm. Whether it’s lack of training, time, incentive, money or a combination of many factors, I don’t know. I do know however, when a cooling, refrigeration or air conditioning system fails to perform, runs out of capacity, the most common solution is to add additional cooling equipment. Good data is normally unavailable. Providing a quick solution rather than the best one is common. Read about a similar situation in a hospital in my article, “Excuse Me, I Didn’t Realize Physics was a Democracy”.
The solution we found was definitely the best one for the owner but what about for those who were paid to study the situation and recommended adding equipment, those who would have sold and installed that equipment? Their interests and incentive were not the same as the owner. The plant might have been cooler but all involved except the owner would have been making money while the owner would have been spending it; quite a difference.
Watson: Your solution sounds Elementary to me Holmes; applying fundamental scientific methods to actual data. The energy monitoring system along with your expertise was the key to solving the mystery. It exposed the cause of the problem.
How much money did you make from finding the problem?
Holmes: We made our money from installing the Energy Monitoring System and using the data to find the problem and determine how to reduce the energy costs. We didn’t make a cent from helping the owner avoid spending hundreds of thousands of dollars for equipment he didn’t need. Read the full Case Study
Tell us about your experiences, both good and bad with energy professionals, what has worked and what hasn’t. Send us your comments, thoughts and suggestions on how to improve our profession so we can all continue to learn from each other. Thanks – Holmes & Watson.