Biodiesel company fueling innovation, sustainability.

• Position: Green Energy Biofuel LLC, South Carolina

Fourteen years ago, the biofuel world looked a bit different.

When Beth and Joe Renwick founded what was then called Midlands Biofuels in 2008, restaurants paid to dispose of used cooking oil, which often went to landfills. Now, the market in which Green Energy Biofuel competes requires wooing customers while making greener, more sustainable use of oil and other food waste.

"Restaurants owners, and everyone, have become more educated that there's value in the oil, and so now it's more of a competitive market," said Beth Renwick, company majority owner. "You have to approach the restaurant and offer them good service and offer them premium price for their oil, or they'll go to the next company to collect."

Renwick, who is also an emergency room physician, and her husband started the company on a small scale spurred by necessity. After his job selling pharmaceutical drug manufacturing equipment ended when the owner of that company died, Joe Renwick began tinkering with producing biodiesel in his garage from cooking oil recycled from a restaurant in Augusta, Ga., when the Renwicks lived in North Augusta.

While Beth wrapped up her medical residency, Joe made batches of fuel, which he tested successfully in his own truck. Soon after, the Renwicks moved back to Winnsboro, where Joe's father and grandfather had both owned businesses. Beth began working at Lexington Medical Center while Joe launched Midlands Biofuels LLC.

The burgeoning business developed innovations including boilerless technology, which heats biodiesel to more than 230 degrees, allowing for recovery of 94% of methanol after the chemical reaction at a fraction of the cost of a traditional boiler. The company soldiered on through the Great Recession and cuts in federal biodiesel production subsidies, securing a contract with U.S. Foods. The Renwicks opened a second processing plant though both the contract and plant vanished in 2011 during an industry downturn.

After years of helping out, Beth Renwick joined the company full time in 2012 and became majority owner, making the firm the only woman-owned biodiesel company in the country.

The business' focus broadened into a large-scale waste processor of biodiesel products, and the company changed its name to Green Energy Biofuel in 2016, when it also expanded throughout South Carolina and Tennessee. The company now operates three processing plants, processes 200,000 gallons of product daily and serves customers in Ohio, Pennsylvania...