The next chief executive of PG&E Corp. has spent the better part of three decades working for large electric companies, so he comes to his new job with a wealth of experience — and baggage that is already generating criticism in California.

In his most recent role as CEO of the Tennessee Valley Authority, Bill Johnson’s advocates have credited him with slashing debt, reducing operating expenses and achieving strong safety records.

But detractors say Johnson, 65, lacked a sufficient commitment to renewable energy, allowed lavish spending on aircraft and poorly handled the ongoing fallout from a major coal ash spill that happened before he arrived.

At the Tennessee utility, Johnson was the nation’s highest-paid federal government employee, according to the Knoxville News Sentinel, with total compensation of $8.1 million for the 2018 fiscal year.

He may be best known for a different part of his resume: serving as CEO of North Carolina’s Duke Energy Corp. for less than one day after the company merged with another utility he led, a flash-in-the-pan tenure that reportedly earned him severance of $44 million.

Experts’ reactions to Johnson’s recent hiring at PG&E, California’s largest and most challenged utility, have been mixed.

One analyst told The Chronicle after Johnson’s new role was announced Wednesday that he was a “safe choice” given his extensive background. But Travis Miller, a utilities analyst for Morningstar Research Services, was “a bit surprised” given Johnson’s lack of California experience.

“PG&E has a lot of stakeholders to win over, and this selection doesn’t seem to check the boxes that many stakeholders were hoping for,” Miller said. “Certainly there’s no doubt that Bill Johnson has proven to be a good utility operator and a good financial steward.”

The Tennessee utility and PG&E said Johnson was not available for an interview. In a statement when his appointment was announced, he said he was “humbled to take on this new challenge and am dedicated to meeting the high expectations that our customers, regulators and legislators have for PG&E.”

When he takes the reins at PG&E, expected later this month, Johnson will have the challenge of leading the utility through its reorganization in Bankruptcy Court, where it sought protection three months ago because of its mounting wildfire liabilities.

Johnson will also be running the huge California energy company, which has 24,000 employees and serves 16 million people, as it tries to avoid being blamed for causing any more major disasters.

Some of the company’s toughest critics question whether PG&E can make the necessary safety improvements now when Johnson’s predecessors were unable to stop the 2010 San Bruno pipeline explosion, many of the 2017 Wine Country wildfires and, most likely, the 2018 Camp Fire from implicating the company.

“Anything’s possible, don’t get me wrong,” said Mark Toney, executive director of The Utility Reform Network, a statewide utilities watchdog. “But it’s hard to have a lot of confidence when his ... predecessors have failed.”

Johnson started his career in law and moved into the utility sector when he joined Progress Energy Inc. in Raleigh, N.C., in 1992. He had various roles at Progress, eventually working his way up to CEO in 2007.

When Progress merged with Duke Energy, another North Carolina utility, in 2012, Johnson was set to be the CEO of the combined company, and he was — very briefly. Hours after Johnson assumed the Duke Energy role, the board ousted him because he “wasn’t right for the job,” the Wall Street Journal reported days later.

While Johnson was CEO at Progress, the utility botched an attempted repair of a nuclear power plant in Florida, according to various news reports. Johnson’s replacement at Duke Energy later indicated the nuclear plant fiasco was one reason the board pushed him out, the Tampa Bay Times reported in 2012.

Johnson left Duke Energy with a $44 million severance package, according to the Times. Duke Energy declined to comment to The Chronicle on Thursday.

Months after his employment ended in North Carolina, Johnson was hired to run the Tennessee Valley Authority, a federal agency that provides electricity to businesses and local power companies serving 10 million people in seven states.

At the authority, he helped reduce operating and maintenance costs by $800 million annually and cut billions of dollars in debt, according to spokesman Jim Hopson.

Hopson described Johnson as a “very inclusive” leader who excels at motivating companies while “explaining those motivations to employees, especially when the hard decisions have to be made.”

“He is not bashful about making difficult choices,” Hopson said. “But he is very sensitive to the fact that those choices impact individuals, both inside and outside the organization. He really understands that.”

Yet Johnson faced a fair amount of scrutiny in Tennessee, too.

High-priced corporate aircraft purchased by the agency on his watch prompted calls for Johnson’s resignation in 2018 amid claims he was “out of touch” with mandates to spend taxpayer money responsibly, according to a report in the Knoxville News Sentinel.

Additionally, a contractor for the Tennessee Valley Authority has been accused of letting workers involved in the cleanup from a 2008 coal ash spill be poisoned. Though the spill happened years before Johnson came to the agency, critics said he mishandled the still-unfolding fallout.

Stephen Smith, executive director of the Southern Alliance for Clean Energy, said Johnson should have aggressively held the contractor responsible and “work(ed) with the people who have suffered the hardship,” but did not. After Johnson announced in 2018 that he would retire from the Tennessee utility, a Knoxville News Sentinel columnist said he “has not spoken to the failures of TVA to monitor” the contractor working on the cleanup.

Hopson defended Johnson and the Tennessee utility against the critiques. He described the aircraft spending as appropriate for the agency’s work in a service territory that includes parts of seven states, and an audit did not find that the uses of the aircraft were inconsistent with federal rules, he said.

The agency is not directly part of the coal-ash cleanup lawsuit and is concerned about the workers’ claims but believes they should be heard in court, Hopson said. Hopson also sought to distance the controversy from Johnson, noting he did not join the company until several years after the cleanup started.

Some clean energy advocates have been worried about the prospect of Johnson running PG&E since they first got wind that he was the company’s leading candidate for the CEO position. After the appointment was confirmed by PG&E, the executive director of Vote Solar quickly released a statement calling the Tennessee Valley Authority a “renewable energy laggard” under Johnson’s leadership.

In naming Johnson as the incoming CEO, PG&E said he had led retirement of more than half of the Tennessee utility’s coal generation, allowing for a similar decline in carbon emissions. But much of that appears to be due to an expansion in nuclear power generation that occurred during Johnson’s tenure — solar and wind remain a relatively small source of power at the agency.

Hopson said that’s because solar and wind are difficult to use as power sources on a large scale in the region. But Smith, of the Southern Alliance for Clean Energy, dismissed that explanation.

“The notion that, somehow or another, solar doesn’t work in the Tennessee Valley is a joke,” Smith said. “That is completely not true.”

Other Southern utilities situated in similar environments have far better renewable profiles, and before Johnson became CEO, the Tennessee utility was “a leader in the region,” Smith said.

“It was under Johnson’s leadership that that all got throttled and pulled back,” he said. “He either does not understand the technology or does not believe in it. ... It’s not that there’s something unique about the Tennessee Valley. There’s a lack of vision by Bill Johnson.”

PG&E, which is also overhauling its board of directors, has not shown any concern about Johnson’s renewable energy record. The utility is expected to be a key player in helping California meet its ambitious climate change goals.

“We believe that Mr. Johnson, along with the newly constituted board, will help PG&E address California’s evolving energy challenges and deliver what our customers expect from their energy company,” PG&E spokesman James Noonan said in an email.

PG&E has also said that the Tennessee agency earned its best safety records with Johnson in charge, and “has been a perennial top decile safety performer in the utility industry.”

Johnson is eligible for a $12.8 million retirement package, according to a Securities and Exchange Commission filing. Some of that was included in his $8.1 million total compensation for the 2018 fiscal year, Hopson said.

PG&E did not reveal how much it will compensate Johnson, saying the details will be disclosed in public documents at a later date. More than half of Johnson’s incentive pay will be “directly tied to safety performance and metrics,” Noonan said, an arrangement that the company believes “significantly exceeds industry standards.”

Total compensation for Johnson’s former CEO Geisha Williams, was about $8.6 million in 2017, the most recent year for which information is publicly available.

Williams left the company in January, just before PG&E announced it would file for bankruptcy protection later that month. The CEO role has been filled on an interim basis since then by John Simon, who was previously PG&E’s general counsel.

In light of the company’s decision to hire Johnson, Simon’s “immediate focus will be to ensure a seamless management transition,” Noonan said in an email. PG&E expects to disclose more about Simon’s future in the coming weeks, he said.

As he steps into his new position, it’s not clear how PG&E will restructure in the coming years — or if it will be able to win over skeptics who distrust the company after its involvement in several disasters over the last decade.

“The burden of proof is on him,” TURN Executive Director Toney said. “He’s coming into a bad situation that has been bad for a long time, and people are going to look at him to win back their trust from scratch.”

J.D. Morris is a San Francisco Chronicle staff writer. Email: jd.morris@sfchronicle.com Twitter: @thejdmorris