Toyota powertrain boss feeling the pressure
His task: Keep internal combustion competitive in the age of electrics
April 21, 2018 - Hans Greimel
TOKYO — Toyota Motor Corp.'s new global powertrain chief has tackled some big challenges in his three decades of designing engines for the automaker.
Hirohisa Kishi not only executed the Toyota pickup's hulking V-8 powerplant, but he also led the troubleshooting of throttle control problems in the 2010 unintended acceleration recall crisis.
But those trials are not as daunting as what he now faces, Kishi says.
As the recently appointed president of Toyota's in-house Powertrain Co., Kishi must keep Toyota's internal combustion engines competitive in the dawning age of electric vehicles.
"Now the doors and possibilities are really opening up," Kishi told Automotive News. "In this changing era, our competitors are not just carmakers. They are coming from all directions."
Toyota's commitment to its trademark hybrid technology actually complicates the task. Toyota is rolling out a new generation of more fuel-efficient and powerful engines as part of a shift to what it calls its TNGA modular vehicle platform. TNGA, short for Toyota New Global Architecture, will yield cars and trucks that are lighter and simpler to build and modify.
But to contain cost, the TNGA engines must be designed for double duty. They must be fuel-efficient and inexpensive enough to pair with a costly hybrid system that clamps on an electric motor and pricey battery. But they also must be powerful and dynamic enough for a traditional vehicle.
Toyota's solution has been adopting a lean-burning, direct-injection Atkinson-cycle engine for the hybrid, and then tweaking that engine for its nonhybrid stablemate. It marks the first time Toyota has put an Atkinson engine in a vehicle that isn't a gasoline-electric one.
The technology leverages some clever tricks in air intake and achieves impressive thermal efficiency rates of as high as 41 percent. But even Kishi, who took over as powertrain boss in January, admits they are incremental advances.
By contrast, rivals in Toyota's own backyard are reaching for big breakthroughs. And they are churning out increasingly sophisticated, cleaner engines.
Nissan has developed a power plant that uses variable-compression ignition. And Mazda is banking on a complicated spark-controlled compression ignition system.
Meanwhile, Honda is making widespread use of downsized turbochargers.
Kishi said Toyota does research on such engine technologies. But he conceded Toyota is playing catch-up in the advanced combustion systems being pioneered by Mazda and Nissan.
"We are behind them from the perspective of introducing the technologies to the market," Kishi said. "And as an engineer, I feel bad and I respect our rivals."
Toyota is opting for internal combustion engines that can work with its hybrid system and still be affordable enough for widespread deployment.
"For a green powertrain, a high level of penetration and popularity is important," Kishi said. "We think that the current strategy of having a simple internal combustion system, and leveraging that in terms of high efficiency and performance, is the best approach."
Like other automakers, Toyota is getting squeezed by opposing trends.
Conventional powertrain costs are increasing as carmakers resort to more sophisticated technologies to meet more stringent emissions regulations. At the same time, EV costs are rapidly falling, thanks to better power density in batteries and bigger economies of scale.
Nissan, which aims to sell 1 million electrified vehicles by 2022, expects electric vehicles and conventional ones to achieve cost parity sometime in the mid-2020s.
Toyota is more conservative. Kishi believes EVs will still cost more, even in 2030.
Gasoline-electric hybrids, by contrast, have already reached parity with gasoline-only engines, when fuel economy is taken into account, he said. While it is technically feasible to make a gasoline engine that delivers the same fuel economy as a hybrid, it would cost more, he said.
"An internal combustion engine, with things added to equal the fuel economy performance, can actually be more costly than a hybrid," Kishi said. "Therefore, in terms of technology, it's possible to make happen. But we don't think it's appealing from the marketing perspective."
By 2023, new engines and transmissions will power 80 percent of new Toyota vehicles. The switch to TNGA powertrains will cut its overall fleet emissions 15 percent from 2015 levels.
There are other big savings.
The rollout will reduce the number of engine types by 40 percent, simplifying production and development and cutting costs. R&d costs, for example, are down 10 to 20 percent, Kishi said. And Toyota was able to slash capital expenditures 40 percent.
To be sure, Toyota isn't ignoring the rush to electric vehicles. In December, it said it plans to introduce more than 10 EVs worldwide by the early 2020s. But Kishi says the bridge technology will be more efficient engines. By 2030, Toyota expects 90 percent of its cars to still be equipped with a gasoline engine, the majority of those mated to a hybrid system.
The question is how to get the biggest gains at the lowest cost.
"We just have to stay the course of gasoline internal combustion technology, improving as we go along," Kishi said. "It's step by step. You have to cumulatively add to your building blocks."