Inventors pack power into miniature compressor

SANDPOINT — More than a century ago, Charles H. Taylor had a bright idea. He wanted to achieve what, until then, had been the purely theoretical notion of what the French called the “carnot cycle” — generating power by using ideal thermodynamics that generate no heat while creating enormous compression.

Drawings and diagrams of Taylor’s subsequent inventions showed up in engineering textbooks for the rest of the 20th Century, always listed as examples of what was still being touted as mere theory.

Funny thing, that, since Taylor’s compressors had long been in use to supply compression to mines and then power the towns that sprung up around them. So successful was this invention — and so marketing-minded the man behind it — that he even scheduled tourist events around the regular “blow-offs” that were necessary because of the surplus of compressed air that the mines and towns couldn’t possibly use up. People gathered around to watch as towering spires of water shot out of the ground in the industrial equivalent of the way Mother Earth uses Old Faithful to relieve underground pressure.

The mechanics of the Taylor compressor were simple enough: Bore a tunnel straight into the ground, add falling water, harvest the compressed air that comes back to the surface through another tunnel after the bubbles shrink and generate compression. No steam, no moving parts, virtually maintenance-free.

The trouble with Taylor’s compressors, however, was their size. He needed a drop of almost 300 feet to produce approximately 130 PSI of pressure. The result, then, was a cavernous combination of tunnels, underground chambers and connecting passageways. Hardly portable. And once electricity became widely available, no longer that attractive, either.

Fast-forward a little more than 100 years to the skunkworks where Mark Cherry and Bob Alderman have been turning out prototypes of an invention they call the Carnot Compressor. Their little gem, they explain, can generate 200 PSI with only about four inches of water. Plus, it’s small enough to rest in the palm of one hand.

Best of all, according to the inventors, it carries with it the primary attributes of Taylor’s work — no heat, loads of compression.

“It’s not like we’re the first people who tried to miniaturize a Taylor compressor, said Cherry, who now acts as chief technical officer for Carnot. “We’re just the first people who have been successful at it.”

“It took us two years and many versions to figure out how to miniaturize the effect Taylor was getting,” said Alderman, the company’s research and development technician and fabricator of the multiple prototypes involved. “We know hundreds of things that don’t work.”

Along with being small, the Carnot Compressor is both quieter and more efficient than the units currently found in applications such as home heating and cooling, refrigeration and natural gas compression. According to Alderman, it also stands to make a difference on construction sites and in manufacturing facilities where large compressors are in place.

“When most of those compressors come on, everybody has to stop talking,” he said. “This one just sits there and hums.”

Quiet as it is, the Carnot Compressor is a mighty little thing, the men behind it said. Where an average compressor generates only about 10-15 percent of the energy put into it, their miniaturization of Taylor’s technology is poised to leave that number in the dust.

“We believe we’ll reach 80 percent or higher,” Cherry said.

Carnot has no plans to go head-to-head with the existing giants in the compressor industry, choosing instead to license the technology to industries where increased efficiencies and less noise would be attractive. Once those industry partnerships are in place, the inventors imagine a time when their product becomes a mainstay in everything from home appliances to job site compressors.

“There is interest — a lot of interest,” Cherry said. “But the first step will be convincing the skeptics. Once you convince them, they become your most enthusiastic supporters.”

Many of those same doubters were schooled in a curriculum that taught that Taylor’s work was based more on speculation than application. Tell that to the 10 mines that were powered by his compressors, Alderman said, including one that generated 6,500 horsepower from a Taylor compressor non-stop between 1910-1990.

“Eighty years of operation with no maintenance,” he said, adding that another Taylor compressor had an even longer run — from 1904-2009 — running a lift-lock gate at Peterborough, Ontario. “It would probably still be running today, but the steel they used to build it finally rusted away.”

As companies become more frugal and appliances adopt increased energy efficiency, ideas such as the Carnot Compressor have a chance to emerge from a century where electricity was cheap and consumption was not an issue, Cherry pointed out.

“Not much has happened in air compression in the last 100 years,” he said. “And, let’s face it, it’s not very sexy.”

“But there was success with this same idea 100 years ago,” Alderman quickly interjected. “Taylor was a genius. He was the Tesla, the Einstein of compression.”