Spring 1985 // Volume 23 // Number 1 // Ideas at Work // 1IAW2

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Lowering Energy Costs for Food Processors


Barry Frey
Extension Agricultural Engineer
Agricultural Engineering Department
University of Maryland - College Park

Donald Schlimme
Extension Food Technologist
Department of Horticulture
University of Maryland - College Park

Rising energy costs have had a substantial impact on the food processing industry, especially the vegetable canning industry. This industry operates on a low profit margin per unit and relies on high volume production to minimize unit cost in a highly competitive environment.

Many Maryland vegetable processors are relatively small-to-moderate size firms that operate seasonally. The vitality of these processors isn't only important for providing employment to rural workers, but has a major influence on farming operations in the surrounding areas. These processors generally lack the technical staff, commonly found in larger firms, necessary to develop and implement energy conservation programs needed to remain competitive.

Initiation and Goals of Program

The Maryland Cooperative Extension Service developed and conducted a pilot program from 1981 to 1983 to encourage energy conservation in the vegetable canning industry using a grant received from the U.S. Department of Energy, Region III. The program focused on boiler and steam distribution systems, since these areas represent about 80% of the total energy used in this industry.1

The program goal was to reduce energy expenditures by nine percent by providing a selected group of small-to-moderate size vegetable canners with the technical help needed to focus their attention and limited capital resources on activities resulting in the greatest energy savings.

Major guidelines used in developing the energy educational outreach program were that the recommendations ultimately provided to the processors: (1) would require minimal capital expenditures, (2) could be implemented with their own personnel or with occasional use of outside contracting services, and (3) would avoid replacing existing machinery and equipment.

Plant Energy Audits

Extension staff conducted an audit of 10 canneries to identify energy-related problem areas. Audits were conducted during a one- to two-day visit at each of the canneries. Return visits were occasionally necessary to evaluate the larger operations or plants processing several products during various periods of the canning season.

The four principal areas of investigation included in the audit were: (1) boiler operations, (2) boiler water chemistry, (3) steam leaks, and (4) insulation of the steam distribution system and thermal processing equipment. Plant management provided information on production hours and standard operating procedures.

Data collected during on-site audits were used to compute boiler efficiency and heat losses from piping, boiler, and processing equipment without and with adequate insulation. The energy savings to be expected from correcting steam leaks, repairing defective steam traps, and eliminating dead-end steam lines were also computed. All associated energy savings were converted to equivalent dollar values based on the previous two years average fuel cost.

A written report was provided to each participating processor itemizing areas of greatest thermal energy loss and providing corresponding recommendations for reducing these losses. The capital cost and benefits of implementing each energy-saving recommendation and an estimate of the capital cost payback period were included for each recommendation. Follow-up visits were made to each processor to discuss audit results and recommendations.


The calculated average reduction in fuel consumption for this pilot program was 6%: 0.6% due to improved boiler operation, 1.0% due to correcting steam leaks, and 4.4% due to insulating piping and equipment. The response from the participating processors to this program has been favorable. Follow-up visits with the processors are planned.


The pilot program was limited to vegetable canners. However, when you consider the potential for only boiler operation energy savings for the several types of food processing industries listed in the footnote reference, it becomes apparent that the opportunity for expanding the program is substantial. Extension faculty in all the states have or can readily develop the skills necessary to conduct energy audits at small-to-moderate size food processing firms. Such an educational program conducted by food science, agricultural engineering, and county Extension faculty could result in significant reductions in energy costs for many small food processors across the nation.

  1. M. E. Caster, ed., Energy-Savings Techniques for the Food Industry (Park Ridge, New Jersey: Noyes Data Corporation, 1977).