In Hart's garage, stacks of batteries capable of powering a car line the walls. A dusty gold-colored Renault is parked with the hood open, revealing battery packs. In one corner sits a cardboard car designed and built by middle-school students to run on batteries.
So when Republican presidential candidate John McCain said last month that the government should pay a $300 million reward to the inventor of a battery strong enough to run an automobile, Hart wasn't impressed.
Batteries are not the problem, Hart said, and he should know. The Sartell engineer has been helping design electric cars for decades.
One of his projects, the two-seat Tango, has been sold to a handful of customers, including actor George Clooney.
Interest in electric cars has risen and fallen in waves since the first ones were invented a century ago. Periodically, politicians talk about pursuing the idea with law changes or funding, but eventually interest wanes, Hart said.
"It's done this over and over and over again for 100 years now," Hart said. Yet today, electric cars remain a "fringe science," he said.
The reason Americans are still driving cars fueled by gasoline Â— despite the rising price of oil and concerns about global warming Â— is because the status quo is difficult to change, Hart said.
Major U.S. automobile manufacturers aren't willing to give them up, he said, and small companies trying to produce electric cars have trouble getting enough capital.
To counter that, Hart has been working on a design for an electric car he hopes can be copied and built by average people. It's a sort of grass-roots countermovement for others tired of waiting for General Motors and Ford to mass-produce alternatives to gasoline-powered automobiles.
"I think you have to build it up piece by piece," he said.
Hart spent the first part of his career as an engineer designing battery chargers and management systems for large companies such as Eastman Kodak and Honeywell, working long hours with little creative freedom.
"I just said enough, I'm not going to do this anymore," Hart said.
He became a contract engineer hired mostly by small, startup companies Â— "mad inventors," he calls them. Hart now tinkers from his home for less pay but more job satisfaction.
The companies who hire Hart don't always stick around long. Some have gone out of business or been bought by larger corporations, which outsourced the design work to a foreign country.
Designing a battery that's powerful enough, light enough and lasts long enough to run a car isn't easy. There have been technological breakthroughs with nickel-metal hydride and lithium ion batteries, but they have drawbacks Â— too heavy, too expensive or potentially flammable.
And electric car engineers have another major obstacle Â— the high standards of U.S. drivers, most of whom don't understand how automobiles work, Hart said. Unlike gasoline-powered cars that have been perfected through mass production, most prototype electric cars have had design glitches, he said.
"If you want perfection, then you're going to spend an awfully long time looking for it," he said.
Still, there have been electric car success stories, including GM's Impact, unveiled in 1990 and later called the EV1. When California mandated the production of zero-emission vehicles, most major automakers began working on electric models.
But after the California regulations were rolled back, most of the electric cars were withdrawn from the market and destroyed, as chronicled in the 2006 documentary "Who Killed the Electric Car?"
Hart was intrigued by a solar-powered car called the Sunrise, produced in the mid-1990s by a company called Solectria. The four-passenger sedan looked like a normal car, could go 65 miles per hour and traveled 375 miles on a single charge.
"It demonstrated that an electric car can work," Hart said. "Its range was every bit as good as a gasoline car."
When Solectria went out of business, Hart and several others decided to buy the rights to Sunrise's design and the remaining parts. They found other parts from salvage yards that had received the cars.
Now Hart and mechanic Tim Medeck of Rice hope to make a kit car that anyone could buy and put together. Like ultralight airplanes built by their makers, kit cars are legal, Hart said.
Hart and Medeck are putting parts stripped from an old Ford Thunderbird onto the Sunrise body. The batteries will be installed in a drawer-like compartment under the car, where they can be easily removed or replaced. Each car likely will cost $10,000 or more, depending on how many extras the driver wants to add, Hart said.
Hart acknowledges that many drivers might be scared off by the serious assembly required, including welding. But he said there's no high-level skill required. It's more of a craft, like knitting, Hart said.
And those who build a few cars successfully might start selling them to others, he said.
"We have to start somewhere," Hart said. "At this point, selling tens a year is a success."
As for McCain's proposal of a hefty cash reward, Hart isn't optimistic it will lead to significant advancement.
The idea has been tried before, he noted. The X PRIZE is a nonprofit prize institute that offers large cash prizes for radical breakthroughs, such as the first private vehicle to reach space.
But typically such contests' high standards make them out of reach for everyone except large companies, which have a stake in preserving the status quo, Hart said.
Instead, Hart would like to see the federal government offer smaller incentives to encourage change, such as tax breaks for consumers who purchase an electric vehicle.
Despite his skepticism, Hart does believe that if gas prices continue to rise, the nation will demand a move toward energy independence.
"There's some point at which people are going to pound on the table and say, 'Enough. I'm not doing this anymore,'" he said.