Energy Matters: Stop the Bleeding
July 01, 2009
by Paul H. Stiller
Does filling a new position in your company require review or approval process? Does headcount or overtime show up on management reports? The answer to both of these questions is a resounding “Yes!” Labor significantly impacts conversion cost and, as such, is carefully controlled.
Now consider what approvals your company requires to increase make-up air in an air handler? Does it have a decision-making process for this significant expenditure? If your company is like most others, the answer is probably not.
I recently encountered this exact situation at a large contract food processing facility in eastern Arkansas. A request to fill a test kitchen position was considered for months while current economic conditions were evaluated. Meanwhile, a utility operator increased the minimum make-up air in a large air handler one day from 10 to 50%. The financial impact of these decisions may surprise you. The air handler adjustment, which was made without review, approval or knowledge of management, cost more annually than filling the test kitchen position.
Why did the operator increase make-up air? Production reported delays thought to be caused by a humidity problem, and the operator fixed the problem. That is exactly what we want utility personnel to do — avoid the problems or quickly fix them when they occur.
However, utility operators need support. They need to know the long-term impact of these quick fixes to be sure they do not create liabilities. Energy is a factor of production that requires the same oversight and management applied to labor, materials and capital.
Follow-up in this case identified the root cause to be vented steam being drawn back into the facility through a make-up air inlet. High humidity was causing a package sealing issue. A modification to the steam vent allowed the make-up air setting to be returned to 10%, and the cost increase was fully reversed.
Employees can significantly and permanently increase energy usage as an unintended consequence of simply doing their job. However, they need training and support so the essential quick fix can later be addressed to eliminate an expensive energy cost penalty.
NOT THAT SIMPLE.
Utility personnel need to act immediately on production issues because procedures that prevent immediate action are penny-wise and pound-foolish. The cost of a production stoppage can dwarf potential energy savings.
So while it is important to allow immediate corrective action, it is also essential to establish a reporting and review process to evaluate whether a more cost-effective, long-term fix can be applied to the problem.
Consider an example from a bakery south of Chicago, IL. A package labeler and transport line began to malfunction around 10 a.m. on April 2007. Based on previous experience, the operator suspected “low air pressure.” The process was critical, and a call was made to the powerhouse. The utility operator immediately increased plant air pressure from 94 to 105 psi and put another compressor online. The production problem was resolved at a cost of $103 per day, or $37,450 annually for additional electric energy.
Spending $103 for a few days to maintain production and sort out the problem is the right decision; surely a bargain compared to the impact of lost production. However, I made a follow-up call in January 2009, and the pressure was still at 105 psi “to keep the phone from ringing.”
The phone should be ringing … from the energy manager or the controller!
If this happened to your labeler, how would the decision to spend $37,450 per year be made, reported or reviewed? Who would be aware of this decision? How would you follow-up?
In this specific case, the line had a low-pressure cutoff switch set at 80 psi. The product-handling equipment requires bursts of air that cause a momentary drop in air pressure, the probable cause of the original problem.
The solution: A small reservoir (20-gal receiver tank) was installed near the labeler to minimize the pressure drops. Now, they have returned to 94 psi supply air and recaptured the $37,450 annual operating expenses. Follow-up on these types of issues is critical.
The powerhouse must continue to support production as a top priority, and operators know and should be allowed the authority to do whatever is necessary to keep product moving. However, the next step in the resolution process is critical to preventing $103 per day from turning into $37,450 annually for years to come.
Any utility adjustment that significantly impacts operating cost must be reported. Someone should be assigned to investigate and understand the root cause of the problem and to recommend the right long-term fix. That will also be money well spent.
Here are other examples you should be able to relate to:
Leaking steam line. In 2002, an underground steam line to a vegetable prep area ruptured at a large plant in northern Ohio. A temporary, poorly insulated replacement was quickly installed above ground. The annual heat loss is worth about $3,000, and the “temporary” line remains in service to this day, almost eight years later. Perhaps you can imagine the condition of the insulation today.
Equipment shutdown. On a Monday morning in April 2008, five hours of production were lost because of sticky pneumatic cylinders on a large printing press (and associated thermal oxidizer) as they were awakened from weekend idle. The decision was made to keep the press and oxidizer on “hot standby” over future weekends. The cost increase was (and remains) more than $75,000 per year. Although this example comes from another industry, the lesson is applicable to bakeries and food processing. You cannot afford to leave equipment on hot standby simply to avoid maintenance.
Demand management. A bakery in upstate New York had some batch controls interlocked to prevent operation during periods of peak electric load. Reduced electric demand charges made this system quite valuable.
In July 2006, a large order required the interlock to be disabled. It was the right decision for that month. However, the interlock was forgotten and never reengaged. Demand charges in 2007 were $24,200 more than would have been the case with the interlock restored.
Other common areas of opportunity include:
- Oven control calibration and set points
- “Adjustments” to ventilation resulting in significant additional intake of cold outside air in the winter
- “Temporary” lighting that is never removed - Blowdown on boilers and water purge on air compressors “temporarily” increased
What to do. Start by making sure that everyone knows the new process should never interfere with production. Short-term fixes are essential and expected. Operators should always have authority to keep the lines up and running, regardless of the energy impact. However, initiate a follow-up process to report utility adjustments and ensure the right long-term fix is implemented. Without reporting and follow-up, temporary fixes are rarely revisited and become permanent liabilities.
Where to look. Wondering if some of these long-term liabilities are lingering in your facilities? Start by looking in the following areas:
- Compressed air pressure increase/oversupply
- General lighting vs. task lighting
- HVAC controls on override
- Ventilation system — increased air changes per hour
- Equipment running on standby because it may not restart
- Steam system condensate lost or excessive blowdown
- Once-through cooling water Motor — pump causally matched in an emergency situation
Most likely, you already have a quality system in place to detect, correct and prevent defects. Do the same for energy-related production issues. Consider those calls from production to be “defect reports” and manage energy with the same rigor applied to labor, materials and capital to ensure that quick fixes don’t become long-term liabilities.