In the autumn of 2004, Philip Farese was at Princeton, thinking about the universe and reconsidering his place in it. He was entering his third year as a postdoctoral researcher. There were experiments to devise, ideas to chase, and other researchers already chasing some of them. His assessment of the situation had the useful quality of being funny at his own expense: “I realized I’m not Einstein.”
He wanted work with more room for his entrepreneurial instincts. He had noticed inefficiencies in how large research projects ran and wondered whether an academic career would give him the kind of discovery he wanted. In 2005, he joined McKinsey & Company. The universe could continue expanding without his supervision. There were organizations on Earth that could use some attention.
Today, Farese is the founder and CEO of Mojave Energy Systems, working on a problem that is easier to encounter than cosmic microwave background radiation: a building that needs dry air without an extravagant electricity bill. Getting there took consulting, national-laboratory research, solar technology, investment work, and an earlier encounter with liquid desiccants. His career makes an unusual argument for changing subjects while keeping the same demanding questions.
A telescope is a good place to learn about evidence
Farese studied physics and mathematics at Cornell, then earned his physics doctorate at the University of California, Santa Barbara. At Princeton he was a research fellow and lecturer. The scientific work was tangible. His name leads a 2003 paper describing COMPASS, a 2.6-meter telescope built to study the polarization of the cosmic microwave background.
The instrument paper discusses optics, receiver design, platform stability, systematic errors, and data analysis. Those are the things that determine whether a faint signal means what an investigator hopes it means. Even an experiment aimed at the early universe must contend with the equipment immediately in front of it. A subsequent COMPASS paper reported an upper limit on polarization from observations made in 2001.
That distinction matters in understanding his later career. Farese had worked on building and interpreting an instrument, with all the awkward distance between a theoretical possibility and a dependable measurement. Years later, his name would appear on another technical paper, this time about air-conditioning equipment operating in Florida, Texas, and Michigan. The scenery changed considerably. The requirement to account for the numbers survived.
The energy you never have to buy
At McKinsey, Farese became involved in examining energy efficiency across the American economy. He was a coauthor and project-team leader of the July 2009 report Unlocking Energy Efficiency in the U.S. Economy. Its concern was the gap between economically attractive energy savings and the obstacles preventing people and organizations from capturing them.
This is an enduringly irritating business problem. A useful technology can exist, the arithmetic can look favorable, and the purchase can still fail to happen. Someone has to decide, pay, install, operate, and accept responsibility. The report examined those barriers alongside the savings. For Farese, efficiency became a practical route into the energy transition, with economics and implementation attached.
At the National Renewable Energy Laboratory, he continued that work as a senior energy analyst. With Rachel Gelman and Robert Hendron, he wrote A Tool to Prioritize Energy Efficiency Investments in 2012. The Department of Energy used the prioritization approach to compare technologies, their costs, and their potential energy savings across a portfolio.
Comparing opportunities sounds tidy until technologies compete for the same building or save the same unit of energy. The tool helped examine those trade-offs. The department described it as one input to decisions, rather than a machine that made decisions itself. Farese was working on the ordering of useful ideas: which deserved resources, and under what assumptions?
His 2012 Nature essay, How to build a low-energy future, addressed the investment needed to bring construction technologies to market and encourage their use. The publication also records a career transition: he had just moved from NREL to Advantix Systems in Florida. The analyst was getting closer to the equipment.
Humidity has been waiting for its own control
Farese went on to lead research and development and serve as chief technology officer at Advantix, which worked with liquid-desiccant air conditioning. Later came strategy leadership at solar company Enphase Energy and research and market-intelligence work at Point72. These roles brought him into contact with product development, commercial decisions, and capital allocation from different directions.
There is a revealing precursor in his 2016 writing about residential energy storage. Farese argued that enthusiasm had outrun installations and that products still needed to meet customers’ practical requirements. He pointed toward integrated systems that made installation, commissioning, and ownership easier. Even then, his attention went to what happened after a promising technology left the presentation slide.
Mojave, founded in 2022 from Xerox PARC research, gave him another chance to work on that problem. Its ArctiDry equipment combines vapor compression with liquid-desiccant technology. The desiccant absorbs moisture; the cooling system manages temperature. Separating the jobs allows the equipment to control how dry the air is without depending on excessive cooling to remove water.
Simplified process illustration. Temperature and humidity can be controlled independently.
A dedicated outdoor air system, or DOAS, treats the outside air supplied to a building. Mojave’s argument is that modern buildings need closer attention to moisture as their heat loads and ventilation requirements change. For an owner, the distinction becomes concrete when the equipment can deliver the required air conditions while doing less work.
A new machine, a familiar installation
Farese has been candid about the difficulty of moving between worlds. When he first entered consulting, he struggled with its urgency and attention to detail. He credits Tom Herbig, a McKinsey partner and former Princeton physics postdoc, with helping him make the transition. Having someone a little further along the same road mattered.
His account of Mojave is similarly collective. Rachel Ellman leads engineering; Aaron Meles leads product; Robert Fancher leads manufacturing. Ellman previously worked at SpaceX and Xerox PARC. Meles brought engineering and product-development experience across energy and industrial equipment. Fancher’s background includes manufacturing leadership and an early career supervising HVAC installation and service work.
That last detail is useful. A product designed to enter existing buildings benefits from knowing what installation actually entails. Mojave manufactures in Anderson, South Carolina, with its corporate office and laboratory in Sunnyvale, California. The company’s geography connects laboratory development with the work of making equipment repeatedly.
In a June 2025 podcast conversation, Farese discussed service, technician training, representatives, and reliability alongside the thermodynamics. These subjects belong together. A contractor must be able to understand the box, commission it, and keep it running. An unfamiliar service routine can make an attractive efficiency calculation feel rather less attractive.
“Respect and understanding for the market.”
Philip Farese, on effective climate-tech leadership
Thirty thousand hours is a different kind of pitch
A certification delay put that practical approach to work. Farese described how Mojave’s testing schedule collided with the industry’s transition to lower global-warming-potential refrigerants. Demand for certification created a bottleneck. A process expected to take six months began looking like a year or more.
The team worked with a testing laboratory to upgrade Mojave’s own testing capabilities. There were late nights and detailed discussions about the requirements. Certification arrived in time to begin shipping. It is a startup anecdote with fewer stage lights than usual: the suspense concerns test facilities and paperwork, and the audience is eventually allowed to buy an air conditioner.
The technical field campaign offers another view of progress. Farese, Ellman, Meles, and reliability engineer Kris Toivola reported on five systems across three states. Their paper compared measured energy use with modeled conventional alternatives. The average estimated savings were 53% against a code-minimum comparison and 32% against an advanced comparison.
The comparison changes the number
The same campaign recorded 31,673 operating hours and 96.9% whole-system uptime. Those figures describe the initial campaign. In September 2025, Mojave announced that cumulative field operation had passed 100,000 hours, reporting 99.7% uptime for its liquid-desiccant systems. The later figure refers to that subsystem, so the two percentages should keep their labels.
For Farese, this is the commercial counterpart of instrument work: state what was measured, know the comparison, and keep accumulating experience outside the laboratory. A building owner has excellent reasons to care about tomorrow morning as well as the annual energy calculation.
The next audience includes old books
One Mojave case study concerns a university archive in northern Florida, where rare books required stable environmental conditions. The company says a system installed in January 2025 supplied air at a 50°F dew point and helped stabilize conditions through humid weather. The attraction of humidity control becomes unusually easy to picture when the contents of the building are a century old.
By May 2026, Mojave had announced ArctiDry Hydro for buildings with existing chilled-water plants. It uses liquid desiccant alongside building water systems, with shipments scheduled for late 2026. The expansion takes Farese’s interest in working with installed infrastructure into another product configuration. Existing buildings arrive with existing machinery, budgets, and constraints.
On September 23, 2026, Mojave announced a $19 million Series B led by Fairtree Elevant Ventures, with River Bay Investments and other new and returning investors. The stated uses were sales expansion, manufacturing capacity, and further product development. The next challenge is producing and selling more equipment while retaining the performance that made the first purchases worthwhile.
Farese has described ambitions to expand internationally and to reach roughly 10% of the dedicated outdoor air market. Those remain ambitions. His route so far gives them a particular character: an interest in the energy a machine can save, accompanied by persistent attention to whether someone will install it. For a physicist who once reconsidered his place in the universe, a working box on a building is a fairly satisfying place to land.