337
was also not a success. Between 1996 and 2003 just over 4,400 BEVs, such as GM’s
EV1 and Toyota’s electric RAV4, were leased or sold (Bedsworth and Taylor 2007 ).
The ZEV mandate had to be amended many times to make it achievable. First, the
1998 and 2001 ZEV sales requirements were dropped. Next, new vehicle categories
and alternative compliance pathways were created. It became possible to substitute
BEV sales with larger sales of HEVs and smaller sales of FCVs. If this sounds all
very complicated that’s because it is. Thanks to the LEV program and its ZEV mandate, California has now a veritable zoo of vehicle categories. Ten years after GM
introduced the Impact, BEVs were all but forgotten again. HEV sales climbed
steadily, though, and more and more car manufacturers offered hybrid-electric versions of their models. At the same time FCVs were increasingly seen as the automotive endgame, with car companies and governments making bold announcements
about the impending rollout of hydrogen cars and infrastructure. While massproduced FCVs always appeared to be another 5 years away, BEVs returned with a
roar in the form of the Tesla Roadster in 2008. Since then many BEV and plug-in
hybrid-electric (PHEV) models have entered the market, the most successful of
which are the Nissan Leaf, the Chevy Volt, and the plug-in Prius. And just when
people started to wonder whether hydrogen cars were a pipe dream after all, Toyota
revealed the Mirai at the 2014 Los Angeles Auto Show, the fi rst commercially available FCV.
All four challengers of the incumbent ICV involve an electric motor and a traction battery. This allows all of them to recover and store the car’s kinetic energy
through regenerative braking. However, motors and batteries differ in size and the
way they are used. In parallel HEVs, the electric motor is combined with an internal
combustion engine (ICE), and both provide torque to the wheels. With typical values between 1 and 2 KWh, HEVs have the smallest traction batteries and thus the
smallest all-electric driving range. HEVs still use liquid fuels, typically gasoline or
diesel, as their exclusive energy source. In PHEVs the traction battery can be
charged directly from an external electric power source. With typical values between
5 and 10 KWh, it is larger than in HEVs, which increases all-electric driving range.
BEVs and FCVs use only electric motors for traction and typically don’t contain
any internal combustion engines. An interesting exception is the Chevy Volt which
has a gasoline engine but uses it only to charge the battery. FCVs have batteries for
intermediate energy storage but use hydrogen tanks for main energy storage. The
fuel cell converts the hydrogen into electricity. Hydrogen is an energy carrier, not an
energy source, and needs to be produced fi rst. Earlier plans for on-board hydrogen
production, e.g., through hydrocarbon reforming, are no longer being pursued. In
BEVs the only energy storage device is the battery, and the only traction device is
the motor. BEVs therefore have the simplest powertrains but also require the largest
batteries.
Battery technology, in particular cost and energy density, has improved substantially over the years and is a key determinant in alternative powertrain choice and
design. GM’s EV1 used lead-acid batteries. Toyota’s HEVs use nickel metal hydride
(NiMH) batteries with roughly double the energy density. All BEVs use lithium ion
(Li-ion) chemistries with roughly four times the energy density of lead-acid
18 The Industrial Ecology of the Automobile
was also not a success. Between 1996 and 2003 just over 4,400 BEVs, such as GM’s
EV1 and Toyota’s electric RAV4, were leased or sold (Bedsworth and Taylor 2007 ).
The ZEV mandate had to be amended many times to make it achievable. First, the
1998 and 2001 ZEV sales requirements were dropped. Next, new vehicle categories
and alternative compliance pathways were created. It became possible to substitute
BEV sales with larger sales of HEVs and smaller sales of FCVs. If this sounds all
very complicated that’s because it is. Thanks to the LEV program and its ZEV mandate, California has now a veritable zoo of vehicle categories. Ten years after GM
introduced the Impact, BEVs were all but forgotten again. HEV sales climbed
steadily, though, and more and more car manufacturers offered hybrid-electric versions of their models. At the same time FCVs were increasingly seen as the automotive endgame, with car companies and governments making bold announcements
about the impending rollout of hydrogen cars and infrastructure. While massproduced FCVs always appeared to be another 5 years away, BEVs returned with a
roar in the form of the Tesla Roadster in 2008. Since then many BEV and plug-in
hybrid-electric (PHEV) models have entered the market, the most successful of
which are the Nissan Leaf, the Chevy Volt, and the plug-in Prius. And just when
people started to wonder whether hydrogen cars were a pipe dream after all, Toyota
revealed the Mirai at the 2014 Los Angeles Auto Show, the fi rst commercially available FCV.
All four challengers of the incumbent ICV involve an electric motor and a traction battery. This allows all of them to recover and store the car’s kinetic energy
through regenerative braking. However, motors and batteries differ in size and the
way they are used. In parallel HEVs, the electric motor is combined with an internal
combustion engine (ICE), and both provide torque to the wheels. With typical values between 1 and 2 KWh, HEVs have the smallest traction batteries and thus the
smallest all-electric driving range. HEVs still use liquid fuels, typically gasoline or
diesel, as their exclusive energy source. In PHEVs the traction battery can be
charged directly from an external electric power source. With typical values between
5 and 10 KWh, it is larger than in HEVs, which increases all-electric driving range.
BEVs and FCVs use only electric motors for traction and typically don’t contain
any internal combustion engines. An interesting exception is the Chevy Volt which
has a gasoline engine but uses it only to charge the battery. FCVs have batteries for
intermediate energy storage but use hydrogen tanks for main energy storage. The
fuel cell converts the hydrogen into electricity. Hydrogen is an energy carrier, not an
energy source, and needs to be produced fi rst. Earlier plans for on-board hydrogen
production, e.g., through hydrocarbon reforming, are no longer being pursued. In
BEVs the only energy storage device is the battery, and the only traction device is
the motor. BEVs therefore have the simplest powertrains but also require the largest
batteries.
Battery technology, in particular cost and energy density, has improved substantially over the years and is a key determinant in alternative powertrain choice and
design. GM’s EV1 used lead-acid batteries. Toyota’s HEVs use nickel metal hydride
(NiMH) batteries with roughly double the energy density. All BEVs use lithium ion
(Li-ion) chemistries with roughly four times the energy density of lead-acid
18 The Industrial Ecology of the Automobile