The energy UC Irvine never used

Not much at UC Irvine looks the way it did in 1994.

The buildings have changed, and many have been added. Computers that once occupied specialized rooms are now carried in backpacks, while research equipment has become more sophisticated and, in many cases, more energy-intensive. The ways students learn, faculty teach and researchers work bear little resemblance to campus life three decades ago.

It was also a consequential time for how UC Irvine thought about the environment. In 1995, founding faculty member F. Sherwood Rowland received the Nobel Prize in chemistry with his former graduate student Mario Molina for showing how chlorofluorocarbons were destroying the Earth's protective ozone layer. Their discovery helped spur a worldwide response, and Rowland became an enduring example at UC Irvine of how research could identify an enormous environmental problem and help do something about it.

At the same time, another effort was taking shape across campus. UC Irvine was becoming increasingly deliberate about the energy required to operate its buildings, setting efficiency goals for new construction and investing in systems that could reduce consumption. The work was less visible than Rowland's discovery, but it reflected a similar conviction that environmental progress could come from questioning assumptions and finding a better way.

Three decades later, almost everything about the campus looks different. One measure is surprisingly familiar.

Cutting energy consumption

UC Irvine today consumes roughly the same amount of energy it did in 1994. That is especially striking when compared with what might have happened. A "business as usual" model maintained by the university estimates how much energy UC Irvine would have consumed without the efficiency measures introduced over the intervening decades. By 2023, actual consumption would have been double what it is now without UC Irvine's aggressive energy programs.

For Joseph Fleshman, UC Irvine's director of energy and engineering, the space between those lines represents decades of work that most people on campus never notice.

"That gap is really the story," Fleshman says. "It represents energy we didn't have to buy, and infrastructure we didn't have to add, while still providing the environments people need to teach, learn and conduct research. No single project got us here. It is the accumulation of decisions made over more than 30 years."

One project at a time

UC Irvine's pursuit of efficiency predates many of the technologies now associated with sustainable buildings.

In the early 1990s, the campus adopted a goal of beating California's Title 24 energy requirements for new construction by 30 percent. Thermal energy storage followed, allowing chilled water to be produced when electricity demand and prices were lower and to be used later to cool buildings.

Over time, the work became more sophisticated. UC Irvine adopted increasingly rigorous LEED building standards and invested in lighting, heating and cooling with building controls, sensors and meters. Eventually, the campus began prioritizing what it called "deep efficiency," looking beyond individual pieces of equipment to reconsider how entire buildings operated.

A major opportunity was found in laboratories.

Research labs are among the most energy-intensive spaces on a university campus, in part because of the enormous amount of air that must be moved through them. UC Irvine's Smart Labs program used sensors and controls to safely adjust ventilation to conditions in individual spaces rather than operating every laboratory at maximum levels all the time.

"A lot of efficiency comes down to asking a very basic question: Does this equipment need to be operating this way, at this level, every hour of every day?" Fleshman says. "When you start asking that building by building and system by system, you find opportunities. Then technology improves and you ask the question again."

Those efforts gained attention well beyond Irvine. UC Irvine became an inaugural partner in President Barack Obama's Better Buildings Challenge and later won recognition through the program. The university also received a U.S. Environmental Protection Agency Climate Leadership Award.

The more telling measure, though, is what happened to actual energy consumption. After reaching its high point in the mid-2000s, it began falling. By the 2010s, UC Irvine was approaching levels it had not seen since the 1990s.

When the campus is also the laboratory

There's another dimension that helped the campus conservation efforts - UC Irvine is a major research university with researchers thinking about and advancing future sustainability innovations. They work just a short distance from the engineers managing it.

Jack Brouwer has spent nearly three decades at UC Irvine studying energy systems. A professor of mechanical and aerospace engineering and director of the Clean Energy Institute, his research includes renewable power, energy storage, hydrogen and the complex systems needed to move electricity from where it is generated to where and when it is needed.

For Brouwer, using energy more efficiently is an important first step in a much larger transition.

"Efficiency is the place you want to start because every unit of energy that you don't need is a unit you don't have to generate, transmit or store," Brouwer says. "But efficiency alone won't get us where we need to go. The next step is making sure the energy we do convert comes from clean sources, and that we can deliver it reliably whenever and wherever it is needed."

UC Irvine offers a distinctive environment in which to work on those problems. Researchers can model and advance future energy systems while the institution around them is addressing many of the same questions at scale: how to power laboratories, heat and cool buildings, accommodate renewable energy and maintain reliability.

"One of UC Irvine's advantages is that we can connect research with deployment," Brouwer says. "You learn something different when an energy technology has to work every day, serve real buildings and real people, and interact with the electric grid. The campus infrastructure, and the supportive and innovative working relationship that we have with Facilities Management allows us to understand not just whether something works technically, but how it works as part of an energy system."

From using less to using differently

After decades spent driving energy consumption down, UC Irvine is confronting a different problem: how to dramatically reduce the fossil fuels needed to operate the campus.

UC Irvine's next challenge is substantially harder. The university's 2026 Climate Action and Adaptation Plan presents a strategy to reduce annual greenhouse gas emissions 90 percent below 2019 levels by 2045. Central to that work is UC Irvine's central plant, where natural gas combustion accounts for more than 90 percent of the campus's operational greenhouse gas emissions.

That makes the next phase considerably more complicated than replacing lights or optimizing ventilation. The central plant provides the reliable heating, cooling and power for laboratories, classrooms and other university operations. Moving away from fossil fuels means finding new ways to provide those services without compromising that reliability.

Fleshman sees the challenge as an extension of the work that came before it.

"The question has changed, but the discipline hasn't," he says. "For years we've asked how we can provide the same or better service with less energy. Now we're also asking how we provide that energy with far fewer emissions. We have to solve both without compromising the reliability that a research university depends on."

UC Irvine doesn't need to look far to see what that next generation of infrastructure can look like.

A hospital without a gas line

Across the San Joaquin Marsh Reserve, UCI Health - Irvine offers perhaps the most visible expression yet of that commitment.

Opened in December 2025, its seven-story, 144-bed hospital is the nation's first all-electric acute care hospital. Instead of relying on natural gas for heating, hot water and other building functions, it was designed around an all-electric central utility plant. Heating, cooling, hot water and steam for sanitizing are produced electrically, with clean electricity and onsite solar contributing to the hospital's energy strategy.

That is no small undertaking for. Acute care facilities never close. They have demanding ventilation, temperature and hot-water requirements. Medical technology requires enormous amounts of reliable electricity, and disruptions can have consequences far beyond an uncomfortable room.

Designing an acute care hospital around electricity meant challenging assumptions about infrastructure that have shaped hospitals for generations.

"Hospitals are exactly the kind of application that makes the energy transition real," Brouwer says. "You can't compromise patient care or reliability. Showing that an acute care hospital can be designed around clean electricity demonstrates that electrification isn't limited to the easy applications. We have to solve it for the difficult ones, too."

The technology may be new, but the underlying question is familiar. UC Irvine has spent decades looking at energy-intensive buildings and asking whether the way they have always operated is necessarily the way the next generation has to.

What comes next

The line marking 1994 on UC Irvine's energy graph makes for a satisfying comparison, but it isn't a finish line.

New technology brings new demands. Research is becoming more computationally intensive, moving activities that once depended on natural gas onto the electric grid. And as California relies more heavily on renewable electricity, the challenge increasingly involves not only how much energy is needed, but when it is available, how it can be stored, and how demand can respond.

The next 30 years of energy management will almost certainly look different from the last 30.

"Getting back near 1994 energy use is something to be proud of, but I don't look at that line and think we're done," Fleshman says. "I look at the gap above it and think about what we learned getting here, and then at what's ahead. There will always be another system to improve and another assumption worth questioning."

In 1994, many of today's energy technologies were either emerging or didn't yet exist. Back then, it would have been difficult to foresee sophisticated buildings responding continuously to real-time conditions, an electricity grid increasingly supplied by renewable energy, or an acute care hospital powered without natural gas.

It is just as difficult to know what UC Irvine's energy system will look like 30 years from now.

The lesson of the past three decades isn't about predicting the next technology. It is about maintaining the habit that produced that widening space between the lines, measure what you're using, question what you actually need, and keep looking for a better way to supply the rest.

After 30 years, one of UC Irvine's largest energy resources may be the one that never shows up on a utility bill: the energy it never had to use.