Keeping Score for Better Energy Efficiency

For many industrial plants and mills, energy costs can be 10 to 20% of their overall business costs. Given these significant costs, leaders in the industrial process industries establish and maintain continuous energy optimization programs to minimize energy cost impact. According to an ARC Report, Best Practices for Energy Management:

Energy can be the largest component of a manufacturer’s cost structure. Despite a recent drop in energy prices, costs are still trending upward over the long term…

I caught up with Emerson’s Bob Sabin, whom you may recall from earlier posts. Bob is an industrial energy consulting engineer who helps process manufacturers establish this continuous improvement process. It starts and carries on with measuring how much energy is being purchased, produced, and used throughout the plant/mill site. It’s important to establish a baseline for steam, electricity, fresh water, air, and process water usage. The perspective should be how much is being consumed by each site area/process. As time goes on, the baseline can be monitored for changes due to equipment issues, energy use can be compared to known industry benchmarks, and projects to improve energy performance can be justified with hard data.

After the survey and measurement phase, it’s important to complete basic tasks such as fixing steam devices, maintaining measurement and final control devices, and addressing control loops that contribute to process variability. This variability directly correlates with higher energy consumption. From there, owners are in position to move on to unit process energy optimization and unit coordination for energy savings.

Often key measurements required to monitor energy consumption are not in place because of capital cost barriers. These barriers have been made higher in the past due to the difficulties in running cable infrastructure to the wired instruments. Bob shared how some industrial manufacturers are using WirelessHART measurement devices to significantly reduce the capital cost barriers associated with installation. Bob noted that energy measurement projects today could be completed at one-third the cost as compared to traditional implementations.

He shared an example where one mill added about 70 wireless transmitters measuring steam flows, condensate returns, water and warm water flows, airflows, and air pressures. Given the old adage, “You can’t control what you can’t measure”, these measurements helped identify inefficiencies in the process and give a true energy usage picture to properly assign the costs. Having this energy monitoring information can also help make better profitability decisions by helping to determine product or grade costs during peak and off-peak hours.

Bob described a case where the site’s steam use had spiked at a heat exchanger during a condensate flood. This helped the operations team more quickly resolve the situation and save considerable energy waste. Another example is how these wireless measuring devices helped spot air, steam, and water leaks that were not being quickly noticed during maintenance rounds.

I got fired up when Bob closed his thoughts to me with a Vince Lombardi quote, “If you don’t keep score [measure], you’re only practicing.” Game, on!

Update: Podcast added.

GreenPodcast.gif MP3 | iTunes

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