Going green is more than just a catchphrase, but it can seem like one to most manufacturers because their primary focus is maintaining operations and production levels. However, if done correctly and with forethought, many manufacturing plants can go green by dramatically reducing their energy consumption and expenditures.
In addition to the "green" benefits of reducing energy consumption, e.g., reducing the site's carbon footprint, the savings that result make this a good business decision. Many energy-reducing retrofits to existing equipment and systems pay for themselves inside of four years, and they provide ongoing cost savings over their useful lives. With an increased emphasis on the environment, the focus on green technology has made it easier than ever to identify and implement efficiency upgrades, beginning with no-cost improvement measures your maintenance staff can implement quickly to those requiring a long-term investment. Here are some key steps to follow:
Get an Accurate Picture: You Can't Change What You Don't Know
The first step in deciding which areas of a plant can be updated is to measure and monitor each facility's energy consumption tied to manufacturing activities. Many plants can do this by pulling together their own metrics, including square footage and hours of operations, and relating this to historical energy cost and consumption information contained on utility bills.
Frequently, manufacturers can avail themselves of real-time energy-usage information by way of a "smart meter." If you aren't sure if your plant has one, contact your local electric utility for more information. For some plants, and for some processes, more detailed information may be warranted. In this case, the plant can install sub-metering to get detailed consumption tracking data on a particular process or system, such as a compressed air plant.
It is important not only to analyze energy consumption, but also to align this information with production metrics. Ask whether or not energy is being put to use efficiently - Is consumption directly necessary to generate production? Many times other information can provide clues on items that might need further investigation; for example, a dramatic increase in maintenance costs for a piece of equipment or system can suggest a problem. It is important to look at the whole picture.
Consider the following scenario: A foundry uses natural gas to heat its boilers; the number of maintenance requests concerning the boilers has increased, while the cost of natural gas has not. This may not set off any energy-efficiency alarms at first, but when coupled with the cost of maintenance and downtime, these boilers are now presenting a big efficiency opportunity that might be realized by replacing them with new equipment.
However you do it, you must have an accurate snapshot of what your plant is consuming, when, and where before you decide where to pursue potential efficiency upgrades. Start with an analysis of at least the last year; you'll want to be able to make an evaluation of the significance of weather and the seasonality of some energy sources such as natural gas.
Decide What's Critical and Set Achievable Goals
By analyzing your energy consumption metrics, some of the most critical areas of concern will reveal themselves immediately. Your snapshot will afford you the ability to effectively identify opportunities for savings from improvements, modernizations, and tweaking some routine plant processes that might easily be improved.
Opportunities generally sort themselves into two kinds of buckets - those that require capital investment and the associated analysis and approval, and those that don't. The latter low- or no-cost upgrades are often a great place to start because they can be accomplished quickly with mostly internal resources, and without major investments.
Retro-commissioning - the process of commissioning an existing building - offers owners and operators a way to improve building efficiency, thereby reducing energy consumption over time and lowering operating costs. Retro-commissioning can occur on any scale, including in a manufacturing environment. It involves the optimization of existing equipment and systems, specifically those that move air, water, and compressed air around your plant. The retro-commissioning field is growing, and it may be a good idea to start your efforts by finding a qualified firm to do this work in conjunction with your plant personnel.
Capital investments can offer significant opportunities to reduce costs while going green. From new high-efficiency lighting systems to variable speed drives, to more efficient chillers and boilers, many technologies can be deployed to reduce consumption and costs. It is important to understand the internal processes and procedures for evaluating capital expenditures at your site before you proceed along these lines. Make sure the people who make these decisions understand the soundness and certainty associated with energy-efficiency investments, and be prepared to have a plan in place to "prove out" the savings over time.
In any case, it is a good idea to dedicate a team or task force to monitor progress, establish goals, and maintain accountability of an efficiency program. Whether it is an outside group or a handful of employees on a task force, establishing an authoritative body to identify weaknesses and maintain the integrity of your investment is a good step when deciding what is critical and how it fits into your company's operational goals.
Execution: What Are the Hot-Button Areas?
Although every case will be different, there are a few common areas where facilities find cost savings and consumption efficiencies.
The first is lighting. In many manufacturing plants, lighting has been long since forgotten. It's overhead and out of the way, and no one pays any attention to it unless bulbs fail and need to be replaced. Well, that old lighting system may be a gold mine for you in your efforts to improve energy efficiency and "go green."
New lighting technologies developed over the past decade can dramatically reduce your costs while simultaneously improving lighting levels and improving burn-hours. And think about lighting controls, too - these can typically reduce lighting usage by 30 to 60 percent based on occupancy. Not all lighting upgrades require new fixtures. As an example, nearly all fluorescent fixtures have retrofit options that can reduce wattage by up to 70 percent. In other cases, antiquated lighting systems can and should be replaced. In addition to cost savings, lighting-efficiency improvements can qualify your company for government tax deductions or utility rebates.
Case in point: One of the world's largest producers and recyclers of lead-acid batteries recently retrofitted the lighting system in its transportation distribution center located in California. The lighting system in this 28,000-square-foot facility had not been significantly improved since construction of the building in 1971. Lights in the office areas were inefficient fixtures containing T12 lamps and magnetic ballasts. The age of these fixtures meant light levels were severely diminished. Additionally, metal halide high-bay fixtures in high-ceiling industrial areas produced inadequate light levels, while consuming large amounts of power. Lighting experts engineered a lighting system for this facility with three goals in mind: to increase light levels throughout the building, to save energy by reducing wattage and operating hours, and to remove toxic PCB ballasts in old fixtures.
The project was completed in less than two weeks, allowing the company to benefit from savings quickly. Energy cost savings totaled the project cost in just over one year. The solution also enabled a rebate from Southern California Edison, which amounted to half of the original project cost, meaning the net simple payback was much less than a year.
The second, and most prolific area where efficiencies can be improved is in central energy conversion and delivery assets, the big pieces of equipment that convert energy from one form to another and move it around your plant. This includes anything from chillers, boilers, and air compressors to HVAC equipment. The idea is to get the most from your existing energy assets and systems - the infrastructure that makes your building work. When equipment or systems are reaching the end of their useful lives or are extremely inefficient, the best course of action is often to replace that infrastructure with new and often dramatically more efficient equipment.
Case in Point: A company was experiencing a great energy drain due to a condenser water pump that was overperforming to serve a minor component of the air-conditioning system. One pump was running continuously during after-hours periods, 12 hours per weeknight and 24 hours each weekend during the day, a total of 108 hours per week. By installing VFDs (variable frequency drives) on the two condenser water pumps, the retrofit would allow the company to control the start/stop and speed signals to the VFDs. It could also implement a lead-lag swap program, so the condenser water pumps would each have equal run times, reducing the wear-and tear on both.
Since installing the VFDs, the facilities have seen a significant reduction in after-hours electrical consumption. The measure has also helped lower pump run-speed during normal operating hours from a constant 100 percent to 95 percent. The annual energy and cost savings is nearly 200,000 kilowatt hours and 10.6 kilowatts in peak demand reduction, and approximately $20,000. In the long-term, this means extended pump life and reduced maintenance, which adds up to an even bigger cost savings.
Make It Count
Anything you do to streamline energy-efficiency practices is going to benefit your company in the end. This is one area where every step counts. It is the responsible thing to do, and evidence suggests that there will continue to be an emphasis on reducing our carbon footprint and increasing sustainable operations.
Change does not have to be intimidating. As stated, something as simple as a two-week lighting retrofit can add up to big savings - all without having to worry about downtime. There are undoubtedly other things you can do today to begin optimizing your energy consumption and "going green." Begin with the following key steps:
• Get an accurate snapshot of energy consumption across all operations.
• Establish a team to identify and implement changes and track success.
• Pursue both low- and no-cost improvements, as well as larger capital improvements.
• Create achievable goals that are important to the business and the people that work in it.
• Use new technology as a means of mitigating maintenance and efficiency challenges and reducing long-term costs.
George Plattenburg is senior vice president of sales and marketing at Servidyne and has more than 20 years of experience in energy-efficiency and sustainability.