I'm rolling down the road in suburban Detroit in the back seat of a 2014 Toyota Prius that has already seen 97,000 miles pass under its wheels. A thought bubble appears above my head: Isn't it time all gasoline-powered vehicles be hybridized?
Judging by how this Prius sounds, feels and performs, you'd never know it has been driven a distance that equals nearly four trips around the world.
The car is one of the newest of 34 Toyota Prius taxis operated by Michigan Green Cabs in southeastern Michigan.
Jonathan Tobias, president of the cab company, says drivers put about 100,000 miles a year on the gasoline-electric hybrids. He believes gasoline-electric hybrids can go the distance with minimal maintenance.
"I would absolutely attest to that," Tobias told me. "A lot of people still think vehicles are used up at 100,000 miles. But in the 36 months we have our vehicles, I don't know anyone who could ride them harder and longer."
Since the company launched in 2008 with the Prius exclusively, only three have suffered any failures related to the hybrid powertrain. The cars stay in the fleet until they reach 300,000 miles then are auctioned.
Toyota hybrids aren't the only ones proving to be reliable and durable under duress. Ford fielded a fleet of 18 Escape Hybrid cabs in New York City from 2005 to 2011. Some were driven nearly 500,000 miles. After they were retired, Ford bought two for its engineers to dissect.
The big worry about hybrids has always been how long the expensive battery pack would last. Ford engineers measured the power output of the retired taxis and found they were nowhere near worn out. The performance falloff was so small, most drivers wouldn't notice, said Bob Taenaka, one of Ford's tech leaders in advanced-battery systems.
"The battery in a hybrid vehicle, when it is delivering maximum power, is when a driver is doing heavy acceleration. A trained driver might observe a slight difference in how fast the vehicle is accelerating, but I'd say the differences are so fine that it really wouldn't be noticeable," Taenaka said.
During a recent tour of GM's new Powertrain Performance and Racing Center in Pontiac, Mich., engineer Matt Laba explained that each part in the 2016 Chevrolet Volt's redesigned hybrid powertrain is tested until it fails. The components, he said, should easily outlast the car and likely won't fail before 200,000 miles.
"The first-generation Voltec powertrain met all our quality targets," said Dan Nicholson, GM's vice president of global powertrain. "We expect the new one to be even better based on our test data."
Bottom line: Hybrid powertrains and battery packs have proved their durability. It's time to make hybrid vehicles the standard. Here's why:
n Boosting production of hybrid vehicles to about 14 million units a year would greatly reduce the per-unit cost of the batteries and hybrid powertrain.
n More hybrids on the road would further reduce the nation's dependence on oil and help clear the nation's air.
n It would help automakers meet the federally mandated 54.5 mpg fleet average by 2025.
In the 1990s, GM made an expensive option -- antilock brakes -- nearly standard across its lineup, saying higher volume cut costs. So there's a precedent. And not every platform and architecture would need a redesign to accommodate hybrid powertrains.
Mild hybrids, usually a belt-alternator system, provide stop-start capability, some assist on acceleration and cut fuel consumption up to 10 percent. A belt-alternator system could be quickly and inexpensively incorporated into nearly all existing vehicles. Supplier Johnson Controls has a fully engineered system on the shelf and ready for mass production.
GM and Toyota have cut the size of full hybrid powertrains to fit the space of a normal four-cylinder engine.
GM, Nicholson told me, is even willing to supply its hybrid powertrains to other automakers if a deal makes sense. Toyota also sells its hybrid technology; it's in Nissan's Altima Hybrid.
Honda and Toyota hybrids have been on American roads for 15 years. The technology is mature and has the potential to pay for itself.