Electric vehicles (EVs) store energy in batteries, but starting this year, EVs that stockpile energy in hydrogen gas tanks—fuel-cell vehicles—will take to the road in small, but growing numbers.
He cited fuel-cell technology as a clean alternative to batteries that runs consistently, one that is easy to integrate with existing hybrid technology and one that scales well from forklifts to buses. “It’s actually very complementary with battery EVs,” Scott said.
“The reality is that a 300-mi (483-km) battery EV at a reasonable cost is not going to happen over the next 5-10 years,” he explained. “And people haven’t signed up to buy EVs in any numbers in the U.S. You might sell 40,000 or 50,000 vehicles a year, but it seems to be too big a change in lifestyle for many customers.”
Toyota estimated that it has cut the cost of the fuel-cell powertrain and fuel tanks by 95%, compared to that of its original 2002 prototype, which, of course, likely cost millions of dollars, tempering the claim.
Start with the fuel cell stack, Farnsworth began. “We removed a very expensive piece of technology, the humidifier, which includes a water pump. Instead, we designed the stack so that water naturally circulates from the cathode where the water is produced to the anode to maintain water content,” he explained. The engineer noted that this was possible because Toyota has learned to measure water content by monitoring the electrical impedance of the stack to register when there is more or less water in the system and controlling it via temperature and pressure.
Despite progress on the vehicle, the paltry number of available hydrogen service stations threatens to keep it at limited production levels. Even early-adopter California has only 19 hydrogen filling stations. They pump trucked-in gaseous hydrogen made from natural gas by two local plants, selling it for around $3/gal equivalent. But Scott said that the state has already approved $200 million to build about 20 new stations by 2015, a total of 40 by 2016, and as many as 100 by 2024.
Toyota targets 2015 for first fuel-cell car - SAE International
