Introduction
This whitepaper is for manufacturers interested in learning how to identify energy waste and eliminating them from the process.
The reasons for energy waste and misuse are not typically done with sinister intentions. Most issues are due to operational concerns and a lack of understanding the tools that are available today. By exploring a plan of attack that breaks down the process, we can look at issues one at a time and fix on a schedule that minimizes down time while increasing efficiency.
This report does not cover energy usage as it pertains to building services, computing, and other administrative energy. Energy waste in these areas are important to address, however, this paper focuses on machine and process energy waste. It will discuss the nature of energy waste, what the most common offenders are as it relates to industry, and what can be done to reduce it.
Electrical Energy Waste in the Manufacturing Sector
As mentioned before, energy waste is not sinister, but typically a mindset that seems harmless. For instance, an employee may decide or be instructed to leave a motor run even when it is experiencing intermittent activity. It is easy to program a pause to shut off a motor and then automatically re-start when a process requires its operation, but to the user that can seem risky.
An employee or manager may think that because these motors are small they don’t use a lot of electricity. The fact is, even small motors running idle draw electricity and this wasted energy adds up over time.
For example, generally a small motor between .5-5horse (for this calculation an average of 2-horse was used) will draw about 1,500 watts/hour. That one motor running for one day will use 36,000 watts (3.6 kilowatts) of energy. Considering that nation wide there are roughly 300,000 factories in the US, how many motors are running idle right now?
The Push Towards Efficiency
Many believe that the climate is changing due to the disruptive nature of human activity, for this group, the reasons to change wasteful ways and become more ‘green’ is apparent and must happen immediately.
Others, that are not on board with climate change. They believe human activity does not have much to do with planetary temperature shifts.
In either case, it all comes down to responsible stewardship of natural resources and taking a full account of the interest of society and future generations. Wasting energy today is using resources that belong to future generations.
Key Offenders of Energy Waste
Key offenders of energy waste are the principal operations that run for periods of time without cause. Examples are conveyor motors, blowers, pumps, vessel agitation, and blending are a few examples of equipment that is left on for long periods of time even when product or materials are not being run.
For instance, a process that has a conveyor taking aborted material away. This conveyor will typically run for hours—if not days—without transporting any material.
Curbing Energy Waste
Reducing wasted energy should start with the basics. Don’t try to fix everything at once because that leads to failure and reverting to the logic that it is just easier to leave it alone. Find a simple energy waster and its most simple problem.
Take the example about the material conveyor in the section above. This problem could easily be solved with a slight bit of programming and a sensor. When production is in operation the conveyor is paused and, when material is present to the sensor, the conveyor will run for a given period of time after the sensor is clear—allowing the conveyor to transport the aborted material to its destination and then pause again until more material is available and ready for transport.
Once you have solved this key issue, continue to monitor and find those operations that energy usage can be reduced.
Part 2 of this series coming soon.
