In 2012, Toyota will start selling an SUV with 100-mile electric range – the RAV4 EV. In 2015, Toyota will start selling an SUV with an electric drive and 400-mile range – the FCHV.
Electrically driven cars could fast become part of our transportation landscape and hydrogen is still in the running as a candidate fuel. As part of the Toyota Sustainable Transportation Symposium April 4-7, 2011, three fuel cell hybrid vehicles (FCHV) were part of the ride and drive. I had driven the original Toyota FCHV some years ago at the hydrogen station in Chula Vista. As I remember it was a Highlander model conversion. While these new ones look similar to the Highlander they could easily be a heavy RAV4.
After years of fleet tests, public sales of the FCHV are planned for 2015 or earlier. Toyota wants to have a fuel cell that will last the life of the car. Life cycle cost of the fuel cell, it’s fueling system, car components, and hydrogen as a widely available fuel are all challenges. I have been an early and continuing skeptic that there was any path to an affordable sustainable fuel cell for vehicles. Toyota is changing that by focusing on the economies-of-scale mass production technology and costs to drop the price to a small fraction of 2001 prices for the fuel cell and hydrogen fueling system. For now, Toyota has built 100 prototype FCVHs to put into fleet customers’ hands for demonstration in the U.S. If you would like to have one, the biggest requirement is having a hydrogen fueling station available.
Test Drive of the Toyota FCHV
Driving the test vehicle was smooth and quiet. I didn’t hear any of the fuel cell throttle compressor sounds, but occasionally heard the cycling of a small vacuum pump. This is a well-engineered comfortable functional small SUV. The overall design for performance and functionality matches today’s standard production cars for city and highway driving. The 10,000-psi compressed H2 fuel tank is well placed on the bottom rear of the car and does not cut into the storage space. To buffer the fuel cell power ramp rates to match the vehicle demands, Toyota uses a standard Prius battery that is also used to recycle the braking energy like a standard hybrid. There is masterful packaging of the fuel cell, electric drive and accessory components to neatly fit under the hood. The PRND selection lever had the extra “B” position like in the Plug-in Prius for getting more deceleration from the braking regen if desired. The passenger comfort controls, entertainment, navigation, and communication accessories are following the overall Toyota telematics evolution.
Looking at the range, efficiency, and operation side of this car, the numbers are impressive – 433 miles on one tank fill of 6.34 kg H2. One kg of H2 has energy content very close to 1 gallon of gasoline. That is 68.3 miles per gasoline gallon equivalent, about the same I got with the Plug-in Prius At 4,100 pounds, the FCHV is a bit heavier than the RAV4 EV. Both use a 90 kW electric drive motor. The drag coefficient is about .33 compared to the .25 for the Prius. Drag and weight are the two biggest factors when looking at average vehicle fuel efficiency. Braking energy recycling through regeneration and energy storage batteries also helps.
Carbon Intensity Comparison of Hydrogen Fuel Cell and Battery Electric Cars
The gasoline hybrid Prius is hard to beat if wasn’t for all the consequences of using gasoline as a fuel. Electric cars look much better as the electric energy mix moves to renewable energy and hydrogen fuel cell vehicle will depend heavily on the source of the hydrogen fuel. The FCHV is already in the competitive energy range. Whether or not the FCHV sells in 2015 will depend on whether or not the cost of the fuel cell comes down to the sustainable range, the hydrogen fueling infrastructure, the cost of other fuels, and the real or perceived penalty associated with GHG fuels. Here are some estimates:
Let’s assume that we want to look at the carbon intensity of using coal and petroleum carbon based fuels where: 34% is the carbon intensity of a coal burning power plant with 7% transmission and distribution losses, 36.6 kWh is the energy content of each a gallon of gasoline and a kg of hydrogen, a Prius gets about 285 Wh/mi, 13% of the plug-in Prius miles are on the battery, and the whole country will eventually go to 33% renewable energy with 7% transmission and distribution losses for our electricity. The 33% renewable added to the coal powered grid increases the carbon intensity to about 50%. The 50% is even higher for the combined cycle natural gas power plants. The carbon intensity of making hydrogen is about 50% by either electrolysis or reformation, but new processes could increase this up to 70%.
- Mitsubishi iMiev ~ 270 Wh/mi @ 27% of the power plant = 1000 Wh/mi; with 33% renewables @ 50% = 540 Wh/mi
- Nissan LEAF ~ 320 Wh/mi @ 27% of the power plant = 1185 Wh/mi; with 33% renewables @ 50% = 640 Wh/mi
- Toyota Prius ~ 50 mpg @ 36.6 kWh/gal = 732 Wh/mi, neglecting gasoline distribution costs
- Toyota Plug-in Prius ~ 67 mpg + 13% elect miles = (732*.87) + ((285/.27)*.13) = 774 Wh/mi; with 33% renewables @ 50% = 711 Wh/mi
- Toyota RAV4 EV ~ 370 Wh/mi @ 27% of the power plant = 1370 Wh/mi; with 33% renewable @ 50% = 740 Wh/mi
- 6. Toyota FCHV ~ 68.3 mi/kgH2 @ 36.6 kWh/kgH2 = 536 Wh/mi, which has to be degraded by the carbon intensity of making H2 @ 50% = 1072 Wh/mi; @ 70% = 765 Wh/mi. If the hydrogen is made from renewable energy on site the number goes to 0 Wh/mi, because no carbon fuels are used directly.