Improving efficiency
Nissan improves fuel efficiency of ICEs through the improvement of engine thermal efficiency, Continuously Variable Transmission (CVT) efficiency, weight reduction and electrification.
Variable Compression Turbo engine (“VC Turbo”) and CVT
The "VC Turbo" engine is able to freely change the compression ratio, which is the most important parameter determining efficiency and power. This makes it the world’s first mass produced engine to meet customer's demand for very low fuel consumption and high power, which are parameters usually in a trade-off relationship. The “VC Turbo” is currently being installed in the Infiniti QX50 and Altima in the US and China.
“Mirror bore coating” technology has been applied to improve the efficiency of gasoline engines, including the “VC turbo” engine. Instead of using a conventional cast iron cylinder liner, this technology reduces mechanical loss and weight by spraying molten iron on the inner wall of the cylinder where the piston moves up and down.
Detail of the VC Turbo engine in the Infiniti QX50 (Structure showing the multi-link system rotating the crankshaft)
Also, the Continuously Variable Transmission (CVT) is being promoted as a technology to improve fuel consumption through its “stepless” gear ratio change capability. Based on the vehicle speed, the CVT system can adjust the gear ratio to the most efficient engine rotation speed and deliver both smooth and powerful driving in low and high speeds, as well as low fuel consumption. Nissan uses CVT technology in a wide range of models, from mini-vehicles to medium sized cars, e.g., 3.5L class.
Smart Simple Hybrid and e-POWER
Powertrain electrification is advancing with the Smart Simple Hybrid system in the new Dayz, and e-POWER system in the Note and Serena.
The Smart Simple Hybrid technology improves fuel efficiency by capturing kinetic energy through regenerative braking using a motor connected to the engine with a belt, and reusing it for acceleration. The new Dayz increases the amount of regeneration by combining a high capacity lithium-ion battery, which ensures energy reuse without losses.
Note with e-POWER system
The e-POWER system in the Note and Serena is a new power unit that combines a gasoline engine and a motor, where the electricity generated by the gasoline engine is used to deliver power to the vehicle through the motor.
In
the
e-POWER
system,
the
gasoline
engine
is
not
directly
connected
to
the
engine
or
wheels,
making
it
possible
to
generate
power
at
most
efficient
engine
rotation
speed
and
torque.
It
has
excellent
performance
in
improving
fuel
efficiency
when
driven
in
urban
areas,
where
cars
are
frequently
used.
In
addition
to
fuel
efficiency,
the
e-POWER
is
driven
100%
by
a
high-power
motor,
which
is
also
mounted
on
the
Nissan
LEAF
in
order
to
achieve
quiet,
powerful
and
responsive
acceleration.
Generator, battery and motor in the e-POWER system
Toward Lighter Vehicles
Vehicle weight reduction makes important contributions to improve fuel efficiency. Nissan is promoting vehicle weight reduction by optimizing vehicle body structure, developing better forming and joining techniques and substituting materials.
In the field of material substitution, Nissan has put its own 1.2 gigapascal (GPa) Ultra High Tensile Strength Steel with High Formability, the world's first such material to combine these levels of tensile strength and workability, to use in the Infiniti Q50 (marketed in Japan as the Skyline) and the Murano in North America and, in 2016, in the Infiniti Q60. And in March 2018, Nissan became the first carmaker in the world to use Super High Formability (SHF) 980 megapascal (MPa) Ultra High Tensile Strength Steel for the front and rear members and other body frame parts of the Infiniti QX50 launched in the United States.
These Ultra High Tensile Strength Steel reduces the amount of material used while allowing production on the same lines, making it possible to create lighter cars with thinner components while reducing total costs. Nissan plans aggressively to expand the use of Ultra High Tensile Strength Steel, aiming for it to make up 25% of the company's vehicle parts by weight, and is actively pursuing new application technologies for it. The material makes up 27% of the new QX50 and enhances driving performance while reducing the vehicle's weight.
Nissan is developing weight reduction technologies for reducing CO2 emissions and reducing use of new material.
Projects to Ease Traffic Congestion with the Use of ITS
Fuel
consumption
is
greatly
affected
by
traffic
circumstances
and
the
way
a
car
is
driven.
We
are
actively
working
to
bring
about
social
infrastructure
that
will
help
to
improve
the
traffic
environment.
This
includes
efforts
to
solve
difficult
road
traffic
problems,
such
as
the
alleviation
of
congestion,
which
cannot
be
achieved
by
individual
automakers.
We
recognize
the
importance
of
intelligent
transport
systems
(ITS)
technology
in
overcoming
these
problems,
and
are
working
together
with
other
industries
for
the
practical
realization
of
ITS.
What is ITS?
Intelligent transport systems use advanced communications technology to link information on humans, roads, and vehicles in a network, and reduce road traffic problems such as accidents and congestion. ITS can link with road communications equipment and other infrastructure, and use information on the status of nearby vehicles and the surrounding traffic environment to help raise fuel efficiency, alleviate congestion, and improve safety.
Projects using ITS
The SKY Project in Japan
Nissan
began
the
SKY
Project
in
October
2006
to
reduce
traffic
accidents
and
ease
congestion
using
ITS
in
Kanagawa
Prefecture,
a
major
Nissan
hub.
A
significant
feature
of
this
project
is
the
collection
of
real-world
vehicle
data
from
our
customers
to
examine
ways
of
raising
energy
efficiency
by
alleviating
congestion
and
reducing
CO2
emissions
in
daily
driving.
The
project
is
conducted
in
partnership
with
industries
outside
the
automobile
industry,
and
is
moving
ahead
with
the
cooperation
of
related
government
agencies.
Nissan
hopes
to
successfully
demonstrate
the
effectiveness
of
ITS
in
Kanagawa
Prefecture,
and
to
expand
these
systems
to
all
of
Japan
and
subsequently
to
the
rest
of
the
world.
Nissan
is
broadening
its
efforts
to
include
the
use
of
social
infrastructure
in
ways
that
go
beyond
the
boundaries
of
an
automobile
manufacturer.
(1)
Probe
car
traffic
information
(vehicle
location,
speed,
etc.)
is
collected
from
the
car
navigation
systems
of
SKY
project
volunteers,
and
precise
traffic
information
is
processed
at
the
Probe
information
center.
(2)
The
traffic
information
processed
from
this
Probe
information
is
provided
to
the
car
navigation
systems
of
trial
volunteers.
This
allows
a
greater
amount
of
road
traffic
information
to
be
obtained
than
with
the
earlier
VICS
(Vehicle
Information
and
Communications
System).
Using
this
traffic
information
enables
drivers
to
find
a
faster
and
smoother
route,
thereby
helping
to
ease
congestion.