Harold Hay wants to help the world save itself, but he's running out of time.
Forty years ago, Hay invented a simple, inexpensive way to heat and cool a home using the sun's rays, but without the panels and wiring that come with conventional solar energy systems.
He's been pushing for its adoption ever since, trying to find footing in each of the solar industry's last three boom-and-bust cycles.
Yet, despite the merits of his pioneering technology, the energy establishment has shown only fleeting interest.
Now 98, Hay is making what he knows will be his final push.
The retired chemist promotes his cause by funding research. He vents his frustration in letters, e-mails, phone messages to anyone who will listen, and on his own website, www.2and50needles.com.
Hay is sanctimonious, unyielding and scathingly critical of other people's efforts and the solar business as a whole. He dismisses the Energy Department as being "in the research-forever stage" and the solar trade as "a bunch of money grubbers."
Hay has no interest in softening his message. He doesn't have time for subtlety.
Hay quotes from an article he's earmarked in Natural History magazine:
"When scientists do science, when they play their game, they debate passionately, and disagree openly, often with brutal honesty toward party lines, sacred cows, or" -- Hay raises his voice for emphasis -- "other people's feelings."
He closes the magazine. "Now that defines me as close as you can get." Hay adds, as if reminding himself, "That's why I'm a loner."
That tenacity has sometimes worked against him.
Over time, people lost patience with Hay and then lost interest in his creation, says Ken Haggard, who designs buildings that use solar energy. Hay's combative personality and reluctance to let others join his mission scotched one potential deal and may have turned others off, Haggard says.
"He's a caricature of the mad inventor," says Haggard, who met Hay in 1972 when the architect was a young professor at Cal Poly San Luis Obispo. "He's a genius. But he's also impossible. And he has not mellowed one iota."
It's tempting to write off Hay as a bitter solar has-been, hoping for immortality at the end of his life. But, given today's energy and climate challenges, ignoring his message and achievements could be a mistake.
"His invention and what he's been saying for all these years is still very, very relevant," says Becky Campbell-Howe, operations director at the American Solar Energy Society, which gave Hay its Passive Solar Pioneer award in 1986.
"The main point that he's trying to make now is that all of our hopes are pinned on all of these complicated technologies, and it's not that complicated. We could solve a lot of the problems by building our buildings correctly."
Hay calls his invention the Skytherm system, and it was a wonder in the 1960s because it used the sun to heat and cool a home. The earliest version operated without any electricity, making it a purely passive solar technology.
Skytherm was the first of what's known today as a roof-pond system. It includes a large mass of water, contained water-bed style in plastic bladders on top of a house. A steel liner subsitutes for regular roofing. The flat roof also holds an insulation panel that moves on rails to cover and uncover the water with the help of a motor, an upgrade from the original rope pulley.
The concept relies on water's tremendous ability to absorb heat. During hot summer days, the water bags are covered by the panel, which deflects the heat of the sun while the bags draw warmth from the house, keeping the interior cool. At night, the panel moves aside and the bags release their heat into the night air. The process is reversed in the winter.
Hay explains the basic theory by pointing out his bedroom window: "Take the black pavement out on the street. It gets extremely hot every day in the summertime -- much too hot to walk across barefooted. The next morning it's cold."
Hay attempts what passes for a shout these days: "You don't need electricity to cool! You don't need an air conditioner! You do it with the sky."
In 1967, Hay scraped together the money to build a one-room test home in Phoenix. The results were encouraging, but yielded no flood of support or funding. It took him several more years, but Hay finally got a full-scale model built in Atascadero, Calif., near the campus of Cal Poly San Luis Obispo.
It was completed in 1973. The next year, Hay testified before Congress, imploring lawmakers to fund research into solar heating and cooling. Two years later, Hay's Skytherm house was recognized by the American Revolution Bicentennial Commission as one of the country's 200 most promising inventions.
In his run-down apartment near downtown Los Angeles, crammed with a lifetime of research, Hay holds up a brightly colored poster celebrating the award; he points to the spot where the Skytherm house is mentioned.