Scheduled for Friday, the final launch of the Space Shuttle Atlantis will mark the end of an era for NASA, the United States, and manned spaceflight. But that’s not all.
The final Shuttle flight means that, at least for now, UTC Power’s long contribution to manned spaceflight also is coming to an end. The South Windsor company that designed and built the Shuttle’s fuel cells will no longer be maintaining the devices that power everything on the spacecraft. But the technology derived from spaceflight is now powering more down-to-earth applications like grocery stores and city buses.
UTC Power began operations in Connecticut in 1958 when the Advanced Power Systems Group at Pratt & Whitney decided to research new power generation methods. A bottom-up effort by engineers there convinced senior management at the time that a burgeoning spaceflight industry needed fuel cell technology.
“Then John Kennedy said in 1961, by the end of the decade we’re going to put a man on the moon. Nobody could figure out how to launch that many batteries into space. So the fuel cell was sort of born,” said Mike Brown, UTC Power’s General Counsel and VP of Government Affairs.
A year later, NASA decided that fuel cells were to be the power source for the Gemini program. Competitor General Electric provided the fuel cells that powered Gemini’s 19 launches (10 of them crewed). But an inopportune fire during the competitive process for the Apollo project knocked GE out of the running, and NASA picked Pratt & Whitney’s fuel cell for the moon missions.
Watch UTC’s Mike Brown explain how an automotive fuel cell works:

Old Tech Redefined in the Space Age
While many consider fuel cells to be a space-age invention, their origin actually goes back to Christian Friedrich Schönbein, who developed the technology in 1838 – long before most people even knew about electricity. The well-known technology lacked a real-world application until the space race demanded a lightweight, reliable, and efficient power source.
Fuel cells aboard space vehicles don’t need to be charged first and can run for the entire life of a space mission provided an ample supply of liquid hydrogen and oxygen are on board. Fuel cells are significantly smaller and lighter than batteries, which is an important benefit for space travel given how cost and complexity increase with every pound that needs to be lifted into orbit.
Like batteries, a fuel cell functions through a chemical process, but it outputs more energy in a much smaller space. It does this by feeding hydrogen through an “anode” and oxygen through a “cathode.” A catalyst in the anode separates the hydrogen atoms into protons and electrons that find themselves attracted to the oxygen atoms on the other side. The hydrogen protons feed through to the cathode side but the electrons are blocked from doing so by a chemical electrolyte. An external circuit connected to the anode provides the escape path for the electrons and electricity is generated as they pass through the circuit to the cathode. Once in the cathode, the oxygen and the hydrogen protons and electrons combine.
Watch a video on how Fuel Cells work:

But the benefits of fuel cells for space travel go beyond just providing an abundant supply of electricity in a small footprint. Fuel cells give off heat and pure water as a waste product – two key components for keeping humans alive in the unforgiving environment of space. It also means that no electricity is needed to heat the cabin and drinking water doesn’t need to be launched – reducing the overall power requirements and the need to launch a few hundred pounds of drinking water every trip.
Transitioning to Shuttle
With a lucrative NASA contract in hand for the moon missions, UTC Power expanded rapidly. The company established its South Windsor headquarters in 1964 where it still operates today. It delivered fuel cells for every Apollo mission through the 1960s and mid-1970s. While it was supporting the Apollo missions it also was working on a next-generation project, and in 1973 the company was awarded a contract to produce fuel cells for the Space Shuttle program.
“The [Shuttle] fuel cells are roughly the shape, dimensions, and weight [of the Apollo fuel cell], but the Space Shuttle fuel cell is 10 times more powerful,” Brown said.
Each Shuttle mission flew with three $12.3 million fuel cells installed just behind the Shuttle’s crew compartment, providing power in tandem and fed by tanks of cryogenic hydrogen and oxygen stored in the Shuttle’s cargo bay. This provided redundancy as well as meeting the power needs of the electronics used in orbit.
The fuel cells generate about 500 gallons of water on each Shuttle flight – far more than astronauts can consume during the duration of a mission. Most of the excess water is supplied to the International Space Station while docked. Connecticut-based Hamilton Sundstrand was tasked with the creation of water recycling systems to help address the lack of Shuttle-produced water in the future.
Read our profile of Hamilton Sundstrand
Brown says the company’s fuel cells have operated flawlessly throughout their service. Shuttle technician Tim Keyser, who spoke with CTTechJunkie.com on a recent tour of retiring Space Shuttle Discovery, agreed. After resolving a few issues related to water production early in their life, they haven’t been a source of trouble.
“We could go another 20 years if they’d let us,” Keyser said.
Watch CTTechJunkie’s Space Shuttle Discovery tour
The Space Shuttle also was the world’s first reusable space vehicle, and the fuel cells UTC Power was contracted to produce needed to be as well. Each could fly five missions before needing to be sent back to South Windsor for servicing. The company produced 34 fuel cells early in the Shuttle program and then serviced them throughout the last 30 years. But as time went on, supporting technology conceived in the 1960s and built in the 1970s and early 1980s has proven difficult in the 21st century.
“We had some problems toward the end where we had difficulty in sourcing because the companies basically went out of that business,” Brown said, referring to suppliers that produced parts for the aging devices. The last refurbished fuel cell was delivered to NASA last year and is now on board Space Shuttle Atlantis awaiting launch.
To Space, and Back to Earth
Knowing the market for spacecraft might not be as abundant as more down-to-earth applications, UTC Power began looking for terrestrial uses. By 1969 it was developing fuel cells for marine applications and in 1976 it conducted a pilot project with Northeast Utilities, connecting a 1-megawatt fuel cell to the power grid.
Work at the South Windsor plant now involves the creation of fuel cells for buildings and vehicles. The South Windsor facility also is home to the only hydrogen vehicle refueling station in New England – a nondescript gas pump that is used to fuel four public transit buses that service the Hartford area. The hydrogen for the plant is extracted by electrolysis using hydroelectric power in Canada and is then trucked to Connecticut. The hydrogen is chilled with giant refrigeration modules to increase the density of storage in the outdoor tanks.
During a visit in June, workers were busy assembling large-scale fuel cells used to generate electricity in commercial buildings. Workers ground the devices during production because once the fuel cell’s panels are stacked, they generate small amounts of electricity from hydrogen and oxygen in the air.
UTC Power has delivered roughly 300 of the commercial units to date, which generate power by extracting hydrogen from natural gas. Like their spacecraft counterparts, the commercial units also generate heat and water that can be utilized without an additional electric or fossil fuel cost. The company says that if the heat from the units is used in an application, they are 90 percent efficient.
What’s Next
UTC Power currently has no new NASA business in the pipeline. The International Space Station is powered by solar panels and NASA’s newly announced Multipurpose Crew Module for long duration flights also will utilize solar technology. But Brown believes that future plans for deep space exploration will make use of fuel cells.
“We’re hopeful that in the future fuel cells will be an integral piece of any long duration occupation of planets or the moon. But those are still quite a number of years off,” Brown said, “If we ever had to do anything on the moon, fuel cells would be the choice.”
But for now the company formed to help the nation respond to a major technological challenge in the 1960s is now using that same technology to tackle a very modern one: finding domestic sources for clean and inexpensive energy.