15 steps to energy savings

It doesn't always take large capital investments to realize improvements in the bottom line.

June 25, 2009

Energy is often identified as one of the highest operating expenses. But reducing energy costs does not have to be a daunting, capital-intensive task.

Resources on energy savings for industries are numerous. For example, the US. Department of Energy's (DOE) Industrial Technologies Program has a mission of transforming the way US industry uses energy, embracing a strategy to drive a 25% reduction in industrial energy intensity by 2017. The strategy also calls for an 18% reduction in US carbon intensity by 2012. The department's website has a wealth of resources for reducing manufacturing energy costs.

As a key element of the program's Save Energy Now effort, DOE conducts energy assessments to help manufacturing facilities of all types across the nation identify immediate opportunities to save energy and money. In the last two years, many companies working in partnership with DOE have already benefited from taking part in assessments. On average, each large plant assessment yields potential savings of $2.5 million. Implementing measures could help save 10% or more per year on energy bills, not to mention productivity improvements and avoided carbon emissions.

Feed Management has identified the following checklist, beginning with an energy assessment, to help not only your plants, but related facilities, improve their energy efficiency:

Conduct an energy assessment, such as the DOE's Save Energy Now assessment, which primarily focuses on energy-intensive systems: motors, process heating, steam, compressed air, fans, and pumps.
In order to improve your energy savings, you need to have a baseline from which to measure your overall progress and allow you to calculate cost savings from specific energy-saving measures. Get your facilities' energy bills for electricity, natural gas, and fuel oil for the past year and determine your total annual energy costs by fuel type and your per-unit energy costs.
Identify the equipment that uses the most energy in your mill. Things to look for include large pieces of equipment and equipment that runs most of the time or that has periodic, but substantial, start-up energy requirements. Include both production and heating/cooling/ventilating equipment.
Develop a facility energy team to track and report energy use, identify energy-saving opportunities, develop an energy plan and implement cost-saving measures.
Operate furnaces and boilers at or close to design capacity. This will decrease fuel consumption per unit of production, resulting in a 1%-5% energy savings.
Measure and control air-fuel ratio or oxygen and carbon monoxide content of flue gases from furnaces, boilers and similar equipment for the entire range of operation.
Clean heat transfer surfaces. This lowers flue gas temperature and increases efficiency by improving heat transfer.
Reduce radiation losses from openings in the facility.
Use proper furnace or boiler insulation to reduce wall heat losses.
Adequately insulate air or water-cooled surfaces exposed to the furnace environment and steam lines leaving the boiler. This helps reduce losses from piping.
Install air preheat or other heat recovery equipment.
Properly size a dryer and the exhaust system. Many dryers can be improved by tuning the exhaust system for the processing conditions. It is important not to undersize a dryer from a production standpoint. However, from an efficiency standpoint, it is critical not to oversize the dryer.
Replace or repair aging or inefficient feed grinding and milling equipment. Give priority to machinery requiring the greatest amount of energy to take advantage of improvements in energy efficiency.
Assess manufacturing and processing techniques. For example, step grinding utilizing either a single or two machines and either batch processing, post mixer or grind system, or circulation grinding may offer the potential of reducing energy with lower grinding costs, finer finished products, more uniform particle size and uniform finished product mix with greater grinding system capacity. Some research suggests the cost of additional capital equipment investment can be offset in less than a year in energy savings.
Don't let your energy assessments end with your plants. Data centers and office facilities can also impact your energy dollar. Replace inefficient lighting with energy-saving fixtures and bulbs. Reduce unnecessary computer use. Utilize energy-efficient doors and windows.