WORCESTER (CBS) – In the wake of a WBZ I-Team investigation into a local home heating oil company, state officials are looking at how they can ensure customers won’t be left in the cold next winter. Since the investigation, the I-Team has heard from more than 20 additional Peterson Oil customers who had problems with their heat. The Worcester-based company also owns Cleghorn Oil.

Nancy Carrigan contacted the State Attorney General’s office. She spent $3,000 on a new tank after she says Peterson’s oil damaged her previous one. She had just purchased a new boiler when her home suddenly went cold after a delivery. “Probably about eight times since the new installation, it went out,” she said. “You have no hot water, no heat.” A spokesperson with the State Attorney General’s office says they’re looking into other complaints.

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Peterson Oil (WBZ-TV)

Michael Ferrante, with the Massachusetts Energy Marketers Association, has been working with state officials to solve problems the I-Team exposed. “The state is absolutely looking into the language in the regulations,” he said. “Based on what’s happened with this company, the state is looking to make modifications.”

Last winter, the I-team went to a lab with fuel samples a former Peterson employee took from several customers’ tanks. Test results showed most contained 80 percent biofuel. That’s fuel made from kitchen grease and other sources. All home heating oil in Massachusetts contains at least 5 percent biofuel, but industry experts recommend no more than 20 percent in blends. They say higher blends can cause problems unless burners are adjusted. Peterson customers tell WBZ they were never informed they were getting any biofuel.

Samples collected by Peterson Oil technician (WBZ-TV)

“I think that’s wrong,” said Brian Tardiff, whose burner was making a strange noise. “It sounds like a little bit of a whine to it,” he said. One morning, after Peterson made a delivery to their Auburn home, Tardiff’s wife called while he was at work. “She had no heat and hot water. It wasn’t working.”

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While Peterson Oil’s owner denied he filled his customers’ tanks with 80 percent biofuel, he did say it was a goal. “We need to be at 80, not 20,” Howard Peterson told the I-Team. “I believe someone needs to go first.” He owns a biofuel plant in New Hampshire.

Howard Peterson owner of Peterson Oil (WBZ-TV)

After the I-Team’s report, the Massachusetts Department of Energy Resources contacted Peterson, requiring him to tell customers what’s in his oil. He’s now added a note to billing statements. “This blend may range from 15-80%,” it says. State officials are now working to make all distributors add similar language to delivery tickets and to start spot-checking delivery trucks. “It’s not difficult to put information on a delivery ticket,” said Ferrante.

Ferrante is also now pushing for a limit on the amount of biofuel allowed in blends eligible for a state program offering financial rewards for selling clean energy. It’s called the Massachusetts Alternative Energy Portfolio Standard. Twenty-eight companies, including Peterson, participate. “The higher the blend level, the better the economics. So there is more money to be made at higher blends,” said Ferrante.

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Ferrante and other industry leaders say they’re concerned Peterson’s problems might turn customers against bio-heat. They want the public to know the state has tested blends of up to 20 percent without any problems. They also say it’s cleaner, renewable and better for the environment.

Christina Hager