Power Electronics Project Leader
Physical Measurement Laboratory
National Institute of Standards and Technology
Developed the “Hefner model” for power semiconductor devices that revolutionized manufacturing of power conversion systems that millions of people use today, leading to trillions of dollars in energy savings worldwide
Tucked inside laptops, refrigerators, electric vehicles and just about all modern consumer electronic devices and high-power industrial systems is a technology called power electronics. The technology “conditions” power that travels from the electrical grid or a local energy source so each different device and system works properly.
The conversion, control and conditioning of electrical power has been the bailiwick of electronics engineer Allen Hefner for most of his 34-year federal career at the National Institute of Standards and Technology. One of his major achievements has been the underpinning of the power electronics industry for the past 20 years.
Early in his career, Hefner developed measurements and engineering models that describe how power conversion and conditioning circuits operate using an innovative type of transistor that has now extended electronics to much higher power levels.
The “Hefner model” revolutionized the U.S. power electronics industry, becoming the de facto standard for manufacturers. Relying on the model to develop these transistors and converter systems, companies have been able to design and market a wide array of products that millions of people use today.
The technology is in fluorescent bulbs, air-conditioning systems, factory robots, solar and wind energy sources, and many other systems and devices.
“You can see the impact of Al’s work across the entire world, across multiple technologies related to stuff we use every day,” said Jim Olthoff, director of NIST’s Physical Measurement Laboratory.
The Department of Energy estimates the improved efficiency stemming from this technology over the past two decades has led to savings of $2.7 trillion for U.S. consumers and $15.8 trillion for consumers worldwide.
“Within the technical community, Hefner is revered because he’s really moved the ball forward in a powerful way, due to relentless contributions year after year after year,” said Robert Ivester, director of the Advanced Manufacturing Office in DOE’s Office Energy Efficiency and Renewable Energy.
Hefner is one of the technical community’s “crown jewels,” Ivester said.
Now on detail to DOE, Hefner is working on the next wave of power electronics. He has advanced from his earlier work evaluating technologies for government programs to creating the programs that support technology development.
Hefner oversees several DOE programs, any one of which could be a full-time job, Ivester said. One is PowerAmerica, an institute working to speed the development and large-scale adoption of newer power electronics technology. “He plays a key role as an expert advisor,” Ivester said.
PowerAmerica funds researchers experimenting with materials that enable power semiconductors to operate at higher voltages, frequencies and temperatures, and will contribute to making power electronics more compact and more efficient.
“It’s a complicated landscape, and Allen has a commanding understanding of it,” Ivester said. “His guidance in this effort has been crucial.”
The institute holds an annual competition for projects, and Hefner helps decide which ones it should fund. He then oversees projects worth millions of dollars, visiting sites where applied-research projects are underway, and calling monthly to check on developments. He works wherever he can to make a difference, Hefner said, motivated by the idea of reducing fuel consumption, enabling use of renewable energy resources and producing manufacturing jobs in the U.S.
“He’s being a crazy mad evangelist; always traveling, visiting meetings and being the facilitator in the room,” said Jon Pratt, chief of NIST’s Quantum Measurement Division. Hefner is helping educate the next generation of scientists getting them into the workforce to create the best technologies.
With all the work underway now, new high-voltage power electronics components are as close as a few years away with applications in high-speed rail, electronics-based power grids, and even hybrid electric aircraft engines, according to Hefner.
“It may take 50 years before power electronics completely changes the [electrical] grid, but we’re already hitting the edges,” he said.
Once this new technology is fully adopted and used in data centers, industrial motors and elsewhere, the fundamental improvements in how electronic devices operate could save 25 percent of worldwide annual energy consumption, according to DOE, and lead to high-quality manufacturing jobs, lower-cost electronics and billions of dollars in energy savings.
“I’m trying to play a constructive role,” Hefner said, and “I’m proud that a lot of the applications we envisioned would be able to use power electronics are now doing that.”