Photo credit: Nostal6ie/iStock/Thinkstock
Ecmweb 15302 Thinkstockphotos 616899444processheatsystemwebversion 0
Ecmweb 15302 Thinkstockphotos 616899444processheatsystemwebversion 0
Ecmweb 15302 Thinkstockphotos 616899444processheatsystemwebversion 0
Ecmweb 15302 Thinkstockphotos 616899444processheatsystemwebversion 0
Ecmweb 15302 Thinkstockphotos 616899444processheatsystemwebversion 0

Improve System Efficiency by Addressing Waste Heat

Aug. 9, 2017
Actively search out sources of waste heat and pursue techniques to recover the wasted heat.

What kind of gas mileage would you expect if you were driving your car with one foot on the gas and the other on the brake? The results from this approach would be pretty poor.

Many facilities have a similar dynamic going on with “waste heat.” Continuing on with the car example, if you look under the hood (and understand what you’re looking at), you’ll see some waste heat recovery techniques in play.

What kinds of techniques might your facility use? Before you can really answer that question, you need to identify the waste heat sources and quantify the amount of waste heat from each source.

Once you have that information, look at processes or equipment that requires additional heat. Many waste heat recovery techniques involve providing at least some of that heat by redirecting waste heat.

Consider a plant that had a small annealing furnace. This furnace used outside air, which had to be preheated in the winter just to get up to the inside air temperature. Meanwhile, several hot process situated nearby were ducting their waste heat air to the outside (and pulling already heated ambient air out as well). Some reducting (along with pressure controls and approval by the boiler inspector prior to actual implementation) changed much of the waste heat into process-used heat.

Another plant had a row of small cooling towers outside the building. A closed piping system ran through the towers. The water cooled a manufacturing process and was simply circulated through the pipes. Hot water ran to the cooling towers, and cooled water ran back to the equipment that needed cooling. This system is very much like the cooling system in a car, except the car has a radiator instead of a row of cooling towers.

The plant had recently hired a new plant engineer, and he noticed almost none of the pipes in the ceiling were color coded or even labeled. So he hired an industrial services firm to identify the pipes. In the process of identifying these, they were amazed to discover that the uninsulated cooling tower return pipe was run between two hot water pipes for about thirty feet. And the pipes were touching each other, causing a loss of energy in the heated water while degrading the cooling system.

Don’t wait to incidentally find instances of gas and brake. Actively look for them. Where are you running hot air, water, etc., and where are you running cooling air or water supply? Where are you generating heat for use, and where are you exhausting heat instead of using it?

About the Author

Mark Lamendola

Mark is an expert in maintenance management, having racked up an impressive track record during his time working in the field. He also has extensive knowledge of, and practical expertise with, the National Electrical Code (NEC). Through his consulting business, he provides articles and training materials on electrical topics, specializing in making difficult subjects easy to understand and focusing on the practical aspects of electrical work.

Prior to starting his own business, Mark served as the Technical Editor on EC&M for six years, worked three years in nuclear maintenance, six years as a contract project engineer/project manager, three years as a systems engineer, and three years in plant maintenance management.

Mark earned an AAS degree from Rock Valley College, a BSEET from Columbia Pacific University, and an MBA from Lake Erie College. He’s also completed several related certifications over the years and even was formerly licensed as a Master Electrician. He is a Senior Member of the IEEE and past Chairman of the Kansas City Chapters of both the IEEE and the IEEE Computer Society. Mark also served as the program director for, a board member of, and webmaster of, the Midwest Chapter of the 7x24 Exchange. He has also held memberships with the following organizations: NETA, NFPA, International Association of Webmasters, and Institute of Certified Professional Managers.

Voice your opinion!

To join the conversation, and become an exclusive member of EC&M, create an account today!

Sponsored Recommendations

Electrical Conduit Comparison Chart

CHAMPION FIBERGLASS electrical conduit is a lightweight, durable option that provides lasting savings when compared to other materials. Compare electrical conduit types including...

Don't Let Burn-Through Threaten Another Data Center or Utility Project

Get the No Burn-Through Elbow eGuide to learn many reasons why Champion Fiberglass elbows will enhance your data center and utility projects today.

Considerations for Direct Burial Conduit

Installation type plays a key role in the type of conduit selected for electrical systems in industrial construction projects. Above ground, below ground, direct buried, encased...

How to Calculate Labor Costs

Most important to accurately estimating labor costs is knowing the approximate hours required for project completion. Learn how to calculate electrical labor cost.