This piece was originally published in the November 2017 issue of electroindustry.
Mike Madsen, Regulatory and Reliability Director, Miller Electric Manufacturing Co.
As a manufacturer of arc-welding equipment, Miller Electric Manufacturing Co. provides innovative and reliable solutions to customers’ metal joining needs. A key component of this is extensive reliability testing.
When reliability-testing a power source, an effective way to emulate a welding arc is to use a resistive load. Unfortunately, all the electrical output energy of the power source is converted to waste heat when using resistive loads.
In 2011, Miller Electric undertook an initiative to make a positive impact on the environment by reducing energy consumption in reliability testing. After investigating many possible solutions, including wind and solar, the company determined that simply recycling the electrical energy using regenerative loads would have the most impact.
A regenerative load is much like a solar converter in that it converts, isolates, and synchronizes the direct current output of the welding power source into alternating current that can be transferred back to the grid. The first regenerative loads were installed and fully functional by November 2015. Since then, Miller Electric has significantly reduced electrical energy usage and receives a favorable return on investment. To date, the regenerative loads have saved more than $100,000 in electrical energy costs.
Miller Electric will continue adding regenerative loads in the reliability test area and may expand electrical power recycling to other test areas.