Industrial Utility Efficiency    

System Assessment

Annual plant electric costs for compressed air production, as operating today, are $147,469 per year. If the electric costs of $750 associated with operating ancillary equipment such as dryers are included, the total electric costs for operating the air system are $148,219 per year. These estimates are based upon a blended electric rate of $0.087 /kWh. The air system operates 8,760 hours per year. The load profile or air demand of this system is relatively stable during all shifts. Overall system flow ranges from 800- 1,000 acfm during production. The system pressure runs from 95 to 80 psig in the headers during production.  

Compressor Controls

UniFirst is one of North America’s largest workwear and textile service companies. They outfit nearly two million workers in clean uniforms and protective clothing each workday. Founded in an eight-stall garage in 1936, the Company has grown to 240 customer servicing locations throughout the U.S. and Canada servicing 300,000 business customer locations. The subject of this article is an energy-saving Air Demand Analysis (ADA), conducted by Kaeser Compressors, at UniFirst’s centralized 320,000 square foot hub Distribution Center located in Owensboro, Kentucky.

Piping Storage

The company specializes in fabrication of precision assembled customized parts for OEM’s and system integrators. Since 1997 the company has steadily grown in size and capacity as the demand for its high quality fabrications has increased.  Through the years, many new CNC machines, laser cutters and powder coat painting operations have been added, but with all the expansion the facility has amazingly kept the plant compressed air consumption low. This has been achieved by following excellent “best practice” compressed air efficiency principles and by keeping watch on system waste.

End Uses

A chemical plant spends an estimated $587,000 annually on electrical energy to operate their compressed air system. In addition, the plant has an expenditure on rental air compressors of equal or greater size - but this will not be covered in this article. The plant was built in the 1940s and modernized in the 1970s. The plant generates its own power and serves many processes. The average cost per kWh is $0.0359.

Pressure

A Canadian chemical plant installed a large heated blower-purge style compressed air dryer, years ago, to condition the instrument air system against freezing temperatures.  The dryer selected was oversized for the connected air compressors and had unused on-board energy savings features.  A compressed air assessment revealed the site air compressors and compressed air dryers were running inefficiently and causing in-plant pressure problems.  Repairs to a compressed air dryer and the replacement of aging air compressors and dryers has reduced compressed air energy costs by 31 percent.

Air Treatment/N2

This plant has three production lines producing snack food. Depending on the time of year and production demand the plant can operate anywhere from no production lines to all three production lines. A thorough supply and demand-side system assessment was done at this plant. This article will focus on some recommended demand-side reduction projects including nitrogen generation, air vibrators, leaks and vacuum venturis.

Leaks

Petro Chemical Energy, Inc. (PCE) specializes in energy loss surveys for the refining and chemical industries. We’ve been providing Compressed Air Leak Surveys, Nitrogen Leak Surveys, Steam Leak Surveys and Steam Trap Surveys – for over twentyfive (25) years. We operate totally independent of all equipment manufacturers to ensure our clients receive a complete and unbiased report of the leaks in their facility. PCE has conducted compressed air leak surveys for hundreds of customers at thousands of sites. Undetected, compressed air and gas leaks rob efficiency in manufacturing and processing industries. As a result, businesses lose millions of dollars annually in energy costs and lost production time.

Pneumatics

Energy, in all forms, has always been a key Lantech focus. It was, in fact, a key element of the core packaging problem the company’s founders set out to address. They saw an opportunity to capitalize on an inexpensive and under-used resource – stretch film – to displace a high materials cost and energy intensive way of unitizing pallet loads of products – shrink bagging.

Vacuum Blowers

Every municipality and utility is facing the reality of rising energy costs. In 2010, the Town of Billerica, MA, which is located 22 miles northwest of Boston with a population of just under 40,000 residents, engaged Process Energy Services and Woodard & Curran to conduct an energy evaluation of the Town’s Wastewater Treatment Facility (WWTF) and pump station systems sponsored by National Grid. The objective of the evaluation was to provide an overview of each facility system to determine how electrical energy and natural gas were being used at the facility and to identify and develop potential costsaving projects.
In February of 2008, a sugar plant near Savannah, Georgia suffered the ultimate tragedy. Fouteen employees were killed and 40 injured when finely ground motes of sugar dust ignited, setting off a violent blast. If the fatalities and a tarnished reputation weren’t enough, the Occupational Safety and Health Administration (OSHA) then fined the company more than 8 million dollars in workplace violations related to combustible dust.
Nuclear power plants produce electricity for people, business and industry.  Electricity is produced in a similar fashion as fossil fuel (i.e., coal, oil, etc.) power plants, using steam to drive a turbines which spin an electrical generator, producing the electricity. 
Industry standards serve a very important purpose for the end users of compressed air equipment.  If the standards are well written, they can help to promote the equipment that they govern, as long as the equipment manufacturers properly apply and promote the standards.
Utilities have been cleaning their boilers for many years using either steam or high-pressure air.  In the past, when air was used, due to the size of the boilers and the reasonable quality of fuel used, a relatively small amount of cleaning was required.
Pneumatic system overhaul for furniture machining center yields high-precision results for a perfect, polished finish.
Boeing Canada has replaced their onsite membrane style Nitrogen generator with a new more modern system with increased capacity and higher efficiency.  As a result, the company is now using minimal amounts of expensive liquid Nitrogen, and has reduced the energy cost per unit of gas produced by 83%.
Relatively few people realize that for a variety of industrial manufacturing applications, from air knife drying to simple blow-off nozzles, the use of high pressure compressed air that bleeds into the atmosphere represents a significant waste of energy.  
Almost every industry in America today is experiencing higher costs – energy, raw materials, labor, health care, shipping – you name it.  Energy prices have been rising and many experts forecast that these increases will continue.  Energy costs sometimes are overlooked when developing productivity and cost reduction plans.
With all of the different LEED credits and associated M&V requirements and tax incentive opportunities for businesses to reduce energy consumption, we have seen an increasing demand for metering. Companies are looking for more ways to estimate cost savings and prove that their energy saving investments are working.
This steel processing facility has been operating for over one hundred years.  This facility is part of a large corporation with numerous plants around the world.  This audit focused on the compressed air system on one side of the Works which we will call the “North Plant”.