David Callen Does Much More than Number Crunching at NRG Energy

The chief accounting officer chronicles how he gained the strength to continuously strive for more

David Callen learned the value of going beyond his limits early in life. As a young man in Israel, after months of intensive basic training for the Israel Defense Forces, he strapped on a pack and set off on a compulsory, ninety-kilometer run along with the other trainees—mostly uphill. “That’s almost sixty miles, and of course I was carrying a forty-pound radio on my back and all of my ammunition, gear, and everything else,” says Callen, who was born in Toronto and grew up in Israel.

“The point is, when you’re pushed to your absolute limit, you learn you can do so much more than you ever believed you could.”

“The point is, when you’re pushed to your absolute limit, you learn you can do so much more than you ever believed you could, and that particular experience is where I truly learned that there’s no such thing as ‘you can’t.’ There’s only, ‘you don’t want to,’” Callen continues.

Now as the chief accounting officer for American energy powerhouse NRG Energy, Callen still draws on that lesson today, as he expands his expertise and pushes beyond the conventional boundaries of his title.

Though his mother and father are both doctors of accounting, that’s not why he initially pursued the profession. But it did add a general sense of comfort, Callen says. “Accounting is the language of business. The real reason I chose accounting was because I saw that people were getting jobs after graduation, and it offered the opportunity to transition easily into other business-related positions. It’s funny, now the one thing I miss most is Excel spreadsheets,” he says of transitioning to a management role.

David Callen, NRG Energy

“Of course the numbers still roll through me, and I’m always there to advise the executive team on them. But this role is more about managing people, making bigger decisions, and helping people think through problems so that NRG and its employees can be the best they can be,” he continues.

To get to where he is today, Callen says he harnessed two indispensable traits: the integrity he developed through his faith, Orthodox Judaism, and the determination ingrained in him by his military training. He also honed in on broadening his skill set, took advantage of opportunities, and kept his big-picture goals in mind. “There’s always a need for somebody to fill holes, and that’s what I kept doing. If something needed to be done I’d say, ‘I’ll do it.’ As I kept doing that, I found myself with more responsibility,” Callen says. “My guiding light—my long-term goal—has always been to become CFO of a large company like NRG. If that’s where I wanted to be, then I knew that, from there, I had to define what I needed to develop in my career.”

After coming to NRG and working as a manager of accounting research, which involves painstakingly deciphering the various revenue streams of the business, Callen grew into process managing the 10-Q and 10-K SEC forms. “Within a year, NRG had made its first acquisition, which almost doubled the size of the company. I played a pivotal role in that process and the SEC filings that came with it. Ultimately, we raised over $10 billion in financings. Immediately afterward, I was made the director of financial reporting in charge of 10-Ks, 10-Qs, and accounting research,” Callen recalls.

A few years in that role made Callen realize he had gleaned a significant amount of experience and was ready for new challenges. “I went to the CFO at the time, and he asked me the same question I ask my employees today: ‘What do you want to be when you grow up?’ I told him I wanted to be a CFO of a company like NRG, and that I had the accounting background, but I needed experience with capital markets, budgeting, forecasting, and investor relations,” Callen says. The CFO then offered Callen a position in the treasury department, allowing him to keep his title and salary while expanding beyond the borders of his experience.

“That was an absolute game changer for me, and it gave me the great opportunity to get out of my comfort zone,” Callen says. “I learned to deal with banks and investors and to negotiate corporate debt facilities; manage project financings and valuations; and analyze ‘repowering’ opportunities—investments in multiple energy projects such as nuclear, coal, gas, wind, and solar. So, I became very specialized in the energy industry and how to think about investments in the energy industry.”

Today, NRG is undertaking a sweeping divestiture and centering its focus on the merchant generation and retail businesses, spurred on by activist investors seeking to ramp up the company’s profitability. Callen is putting his specialized knowledge into practice and playing an integral role on the steering committee, which will implement the board of directors’ overall transformation strategy moving forward. As a part of this committee, Callen is reaching out beyond the accounting functions and partnering with the IT department to spearhead an initiative that will revamp the company’s accounting and business software systems. He sees the legacy systems as one of the company’s greatest obstacles to efficiency.

“This SAP upgrade is going to help make my team dramatically more efficient than it is today, because we still have a lot of accounting processes that are very manual. The more we automate, the more efficient we can become. The more efficient we can become, the more money we save. The end goal is to cut back $640 million of expenditures as per the transformation strategy,” Callen says. “We’re still in the phases of building the business case for the upgrade, but I feel very confident that we’re going to do it.”

When going through a transformation plan of this magnitude, it’s all about thinking outside of the box and adapting the boundaries of the existing culture to what best serves the business, Callen says.

“It isn’t going to be a bed of roses, but at the end of the day, implementing these changes will allow us to provide better services for the customers, and that means more profit for the company and better returns to our shareholders.”

Photo: Eric Melzer/Courtesy of NRG


Duff & Phelps is the leading global advisor that protects, restores, and maximizes value for clients in the areas of valuation, corporate finance, disputes and investigations, and compliance and regulatory matters. It has been terrific working with David Callen on complex valuation projects over the past two decades. Congratulations, David!