Conducting Excellent Energy Audits

Worldwide energy demands and costs are at record levels. Developing nations are gobbling energy with a voracious appetite while speculators bet on their demand, pushing energy and food prices to new highs. Members of the middle class are adjusting their ways of life in response to rising energy prices, while heads of nations are forced to confront the concerns of their citizens and neighbors.

Worldwide energy demands and costs are at record levels. Developing nations are gobbling energy with a voracious appetite while speculators bet on their demand, pushing energy and food prices to new highs. Members of the middle class are adjusting their ways of life in response to rising energy prices, while heads of nations are forced to confront the concerns of their citizens and neighbors. Energy is – or should be – on the minds and lips of nearly everyone.

Food processing plant owners and operators are no exception. However, processing facilities in different locations around the globe face different challenges, and local challenges define local management teams' types and levels of concern. For example, in locations where energy is intermittent and unreliable, the concerns are, "Will we have a constant supply of energy?" "Are there things that we can do in our plant to reduce local demand and reduce the likelihood of an overall shortage?" and "How do we prepare for and what can we do when the power goes out?"

In locations where energy is reliable but expensive, the questions become, "What can we do to reduce power consumption in order to reduce costs, stay competitive and increase profits?" And where energy is both reliable and affordable (assuming such a place does exist), concerns may be along the lines of, "What should we do in order to be more environmentally responsible and better corporate citizens?"

Of course, it is beneficial for any food processing plant to reduce energy costs and usage, regardless of its circumstances.

A new way of thinking

Part of the challenge in reducing food processing plants' energy costs is that cost-saving steps alone cannot re-design facilities' manufacturing processes. That's because those processes are the key to defining process attributes and making the products unique. The only viable energy reduction strategies are those which, in contrast, do not alter product identity. All other strategies are unacceptable.

The first step in evaluating a plant's environmental usage, in fact, has very little to do with the actual facility and nearly everything to do with the people who work there. Facility personnel must embrace — in more than a mere cursory or intellectual way — the belief that energy is a valuable commodity and cannot be taken for granted.

Experience has demonstrated that significant reductions in energy usage and costs are typically most achievable when staff members personally and emphatically commit to saving energy. A pervasive attitude of, "We've never done it that way before" will likely prevent any meaningful change from occurring.

Once attitudes within a facility are sufficiently open to fresh and constructive ideas, then it may be useful for plant owners to engage external energy consultants who specialize in food processing plants. They can often assess a plant with "fresh eyes" and broad experience, and are thus able to identify and recommend energy-saving strategies. The right experts will be able to identify cost/energy cutting ideas that are properly suited to the unique demands of food processing, where cleanliness, sanitation and contamination control standards are obviously much higher than they are in non-food industries.

Facility-based strategies

Of course, some strategies can transfer from outside of the food industry, though, such as regular, stringent meter assessment. Nearly all energy utilities are billed based on meter readings. While most utility customers (business and residential) assume that their metering is correct, that is not always the case. Plant managers should first determine how their facilities are being metered. They should then insist that their utility meters be regularly calibrated, either by internal plant maintenance staff or by the local utility provider. Even a small inaccuracy in utility metering can result in significant overbillings in a large processing facility. Duplicate metering devices, installed to verify billings from utilities or energy providers, have proven to be justifiable in many instances.

An easily identifiable strategy for food processing plants is in the area of heat recovery. Many food processing facilities use extensive oven and furnace-type equipment. If waste heat from those ovens and furnaces can be reclaimed and reused instead of being released into the atmosphere, then the plant could see appreciable energy savings. Reclaimed heat could be redirected into, say, water or air pre-heating processes. While it can sometimes be difficult to recover surplus heat, the potential windfall of that already-paid-for energy makes this strategy worth exploring.

Another area of potentially significant cost savings is in cleaning and changing-over equipment. Food processing equipment must, of course, be regularly and thoroughly sanitized in order to change from one food type to another. It is not uncommon for such clean-outs to take hours or even days. The cost of this down-time in between processes can be extensive, so plants do well to seek ways to minimize it.

One strategy to minimize change-over time is to use high-pressure washers. On the surface, this may seem like an unnecessary energy expense when low-pressure washing can get equipment just as clean. But since a low-pressure wash will likely require significantly more time, water and labor, then a high-pressure system will probably result in reduced energy, water and labor costs.

Similarly, if plant managers rethink their processing schedules, they may able to reduce the number of required change-overs. Fewer change-overs will also result in reduced energy and labor costs.

Some improvements are easier than others

Energy consultants in the food processing business understand that some improvements in production facilities come more easily than others. For example, if no one is in a room, then turn off the lights. If the air conditioning is on in the warehouse, then close the doors. If the plant closes at night, then automatically power down unused systems.

Other improvements may be harder to identify and more expensive to implement. For example, perhaps installing heat exchangers would result in energy cost savings. But that might create costs in additional sanitation, because such systems may also spread contaminants and attract insects.

Nevertheless, it is in everyone's best interests to perform due diligence in pursuing every reasonable energy saving strategy. However, plant investors, owners and managers will be first on the list of beneficiaries through increased profits.

But more than that, energy efficiency just makes sense. Gone are the days when energy consumers had the luxury of dismissing excess energy use as "no big deal" or not worth the trouble to change. The rules of business economics apply as always, in that the most efficient and well-run operations will survive the longest and be most profitable. It's just that energy use has earned its way to a much higher place on the proverbial list of "Items to be Well-Managed" than ever before. And, integral to good management is conducting an excellent energy audit.

For more information about energy audits, contact Dan R. Messinger at dmessinger@ssoe.com.

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