Sterling Steel Company – Sterling, Illinois
Leggett & Platt’s Sterling Steel Company (Branch 0530), located in Sterling, Illinois, is a largescale steel mill that manufactures semi-finished billets and finished rods through the melting of recycled scrap metal in one of the world’s largest electric arc furnaces.
Recycling is just another day at the office for Sterling Steel. On average, Sterling Steel melts approximately 1.1 billion lbs. of scrap metal per year to create new semi-finished billets and finished rod to be used in manufacturing processes throughout the country.
In Sterling Steel’s melt shop, electrical power for overhead cranes was supplied through four motor-generator (MG) sets that were installed between 1951 and 1967. The MG technology was an inefficient method for supplying DC crane power compared to modern technology. In addition, due to age, the power cables were in need of serious repair and had already caused at least one failure.
In February 2010, a team was formed to investigate how to best resolve the MG problem. After almost two years of investigation, the team decided the best option was to update the crane power system with solid state technology rather than repair the outdated existing MG system. Overhauling the MG sets could cost as much as $600,000. Installing the solid state technology would initially be much more expensive but would decrease energy consumption by an estimated $318,000 per year. ComEd, the local power company, offered an energy rebate program of approximately $600,000 if at least one phase of the project was completed by March 31, 2012. In addition, $15,000 would be captured by eliminating annual repair costs for the MG sets and $.3 million would be saved on cable replacement costs by moving solid state drivers closer to the crane bays. Upon completion of the installation, many of the old power cables were harvested for scrap. The salvage value of the old copper cables added up to $150,000 in revenue.
Return on investment (ROI) for the replacement of the MG sets with solid state drives was 49.9%. Adding in the $1.8 million cost to replace the power cables brought the ROI for the entire project to 8.3%.
This project resulted in an energy savings of 7,893,504 kWh per year! That is enough energy to power nearly 874 homes with electricity for a full year!
In more recent years, the facility has implemented programs to reduce waste going to the landfill. The facility supplies about 50,000 bottles of water to employees each summer, which are now sent for recycling. The facility has also identified a way to recycle their Super Sack chemical packaging. They now divert over 10,000 Super Sacks from the landfill each year.
For these and other environmental efforts, Sterling Steel received the 2015 Steel Manufacturers Achievement in Environmental Stewardship Award.