PLEASANT HILL, Calif. (KRON) — A Pleasant Hill man was sentenced to prison Tuesday and ordered to pay more than $619 million in restitution for participating in a billion-dollar Ponzi scheme, prosecutors announced.

The former solar power company executive, 45-year-old Ryan Guidry, was sentenced to serve six years and six months in prison, U.S. Attorney Phillip Talbert said.

Guidry pleaded guilty two years ago to conspiracy to commit an offense against the United States and money laundering.

According to court documents, Guidry worked at DC Solar from 2012 through 2019 and became Vice President of Operations by 2015. “Guidry understood DC Solar’s business model and knew that investors were being defrauded,” prosecutors wrote.

Among those suckered by the business were Warren Buffett’s Berkshire Hathaway Inc.

Two Martinez residents, 52-year-old Jeff Carpoff and his wife, 49-year-old Paulette Carpoff, were also involved in the scheme, prosecutors said.

After Jeff Carpoff founded DC Solar, “(The Carpoffs) and their co-conspirators solicited investors by claiming that there were favorable federal tax benefits associated with investments in alternative energy,” prosecutors wrote.

According to court documents, between 2011 and 2018, DC Solar manufactured solar generators that were mounted on trailers, known as mobile solar generator units. The company touted the versatility and environmental sustainability of the mobile solar generators and claimed that they were used to provide emergency power.

“They sold more solar generators than they manufactured to investors, making it appear that solar generators existed in locations that they did not, creating false financial statements, and obtaining false lease contracts, among other efforts to conceal the fraud. In reality, 9,000 of the approximately 17,000 solar generators claimed to have been manufactured by DC Solar did not exist,” prosecutors wrote.

In 2017 and 2018, when DC Solar was no longer making the MSGs it was selling, Guidry scraped old VIN stickers off of MSGs and put new ones on them at DC Solar warehouses in Benicia and Las Vegas, working with Jeff Carpoff and others. The VIN switching was used to trick investors during inspections.

Guidry accepted $1 million that he knew came from deceived investors to get a signature on a false lease contract, and split another $20,000 in cash with Alan Hansen, 51, of Vacaville, an employee of a telecom company for forging a signature on a related agreement, according to prosecutors.

This case was the product of an investigation by the FBI, IRS Criminal Investigation, and the Federal Deposit Insurance Corporation Office of Inspector General.

On Nov. 9, 2021, Jeff Carpoff was sentenced to 30 years in prison and ordered to pay $790.6 million in restitution for conspiracy to commit wire fraud and money laundering. His wife, Paulette Carpoff, pleaded guilty to conspiracy to commit an offense against the United States and money laundering. She was sentenced to 11 years and three months in prison.

On Nov. 16, 2021, Joseph W. Bayliss, 47, of Martinez, was sentenced to three years in prison and ordered to pay $481.3 million in restitution for securities fraud and conspiracy in connection with the DC Solar scheme. On April 12, 2022, DC Solar CFO Robert A. Karmann, 56, of Clayton, was sentenced to six years in prison and ordered to pay $624 million. On May 31, 2022, Alan Hansen was sentenced to eight years in prison for conspiracy to commit an offense against the United States and aiding and abetting money laundering.

Ronald J. Roach, 55, of Walnut Creek, pleaded guilty to criminal offenses related to the fraud scheme and is scheduled to be sentenced on March 14. He faces a maximum of 10 years prison.

The Associated Press contributed to this report.