It was just the spark the Illinois stone company needed.

Charleston Stone’s 400-horsepower diesel rock crusher had been in operation since 1999 and was showing its age, dropping out of service for maintenance 100 to 120 days a year.

“Diesel obviously has its drawbacks,” said Mike Vaughn, Charleston Stone’s superintendent. “A lot of rebuilding, and it wears the engines out.”

When Coles-Moultrie Electric Cooperative’s key accounts representative heard about Charleston Stone’s production problems, they offered an increasingly popular solution: beneficial electrification.

By switching to an electric crusher, the company could say goodbye to its engine maintenance woes and to diesel price fluctuations.

“If the added load for Coles-Moultrie meant lowering [overall] cost for Charleston Stone, it was a perfect match,” said Sam Adair, manager of marketing and member services for the Mattoon, Illinois-based co-op.

With research from Charleston-based Eastern Illinois University, Coles-Moultrie found that an electric crusher could operate at 95% efficiency while the company’s diesel system operated at 35% to 45% efficiency.

This could save Charleston Stone as much as $5,000 a year in diesel costs and boost the co-op’s electricity sales by about $28,000 annually.

“We do have a little bit higher electric bill, but we have no diesel fuel expense,” said Vaughn.

The co-op secured federal Rural Economic Development Loan and Grant financing to help the company buy the new electric crusher and installed additional service to run the new unit. The new mobile rock crusher includes a mounted transformer that can quickly be wired to pole-mounted terminals.

So far, the move is paying off on both sides of the meter.

“The added load for Coles-Moultrie meant lowering the cost for Charleston Stone,” Adair said. “Their diesel bill far exceeded what their electric bill is now, and [their energy costs are] a lot more stable.”

Since switching from diesel to electric crushing, the company has added five new staff members to its workforce of 20. The changeover has also reduced carbon dioxide emissions associated with its rock crushing and cut dramatically into downtime for oil changes, equipment repairs and mechanical failures, saving as much as $360,000 a year in lost production.

Overall operation of the electric crusher has been flawless since its debut in 2017.

“The electricity seems to be trouble-free,” said Vaughn, adding that the electric crusher operates well even under severe cold winter conditions. “The electric motors are happy at any temperature.”

Amy Borntrager, Coles-Moultrie’s chief financial officer and currently the co-op’s interim president and CEO, said it feels good to help a longtime member. Charleston Stone has been operating quarries along Illinois’ Embarras River since 1958 and is Coles-Moultrie’s 14th largest load.

“We are not a very wealthy community,” she said. “Anything we can do to help out businesses I think is a win-win situation for both of us.”

Read More:

Beneficial Electrification C&I Case Studies: Rock Crushing Equipment

Listen to a related podcast episode: