liter 4-cylinder hybrid
(from Volvo Press
Release) Volvo ReCharge Concept:
Plug-in hybrid with battery-only range of 100 km - and Flexifuel
engine for backup power
Volvo Cars is introducing the Volvo ReCharge Concept, a plug-in
hybrid with individual electric wheel motors and batteries that can
be recharged via a regular electrical outlet for maximum
Recharging allows the car to be driven about 100 kilometres on
battery power alone before the car's four-cylinder Flexifuel engine
is needed to power the car and recharge the battery.
Volvo ReCharge Concept makes its debut in a specially designed Volvo
C30 at the Frankfurt Motor Show.
"A certain proportion of electrical vehicles will be necessary to
meet the CO2 emission demands of the future. Since the Volvo
ReCharge Concept combines an excellent battery range with a backup
combustion engine, it is a very interesting concept," says Magnus
Jonsson, Senior Vice President Research and Development at Volvo
The ReCharge Concept has been developed at the Volvo Monitoring and
Concept Center (VMCC), the Volvo Car Corporation's think-tank in
"This is a ground-breaking innovation for sustainable
transportation. A person driving less than 100 kilometres a day will
rarely need to visit a filling station. In the USA, this may apply
to almost 80 percent of drivers," says Magnus Jonsson.
Thanks to the excellent electrical range from a fuel consumption
angle, the Volvo ReCharge Concept is exceptionally kind to the car
When driving on electric power only, operating costs are expected to
be about 80 percent lower than that of a comparable petrol-powered
car. When driving beyond the 100 km battery range, fuel consumption
may vary from 0 to 5.5 litres per 100 km depending on the distance
driven using the engine.
"This plug-in hybrid car, when used as intended, should have about
66 percent lower emissions of carbon dioxide compared with the best
hybrid cars available on the market today. Emissions may be even
lower if most of the electricity in intended markets comes from
CO2-friendly sources such as biogas, hydropower and nuclear power,"
says Magnus Jonsson.
An electric motor at each wheel
The Volvo ReCharge Concept combines a number of the latest
technological innovations into a so-called "series hybrid" where
there is no mechanical connection between the engine and the wheels.
* The battery pack integrated into the luggage compartment uses
lithium-polymer battery technology. The batteries are intended to
have a useful life beyond that of the car itself.
* Four electric motors, one at each wheel, provide independent
* Four-cylinder 1.6-litre Flexifuel engine drives an advanced
generator that efficiently powers the wheel motors when the battery
Electric car with a combustion engine as backup
In principle, the Volvo ReCharge Concept is a battery electric car
with an efficient generator, an Auxiliary Power Unit (APU), that
steps in when battery charge becomes insufficient for adequate
The APU is designed to distribute electrical power to the individual
motors at each wheel. Since the combustion engine only powers the
APU, it can operate in an optimal fashion, both for regulated
emissions and CO2.
The APU is sufficiently powerful to supply an entire villa with
electricity. For example it could with minor modifications in
principle give the car owner an electricity generator right at his
front door in the event of a power failure.
The driver can choose the power source
The combustion engine starts up automatically when 70 percent of the
battery power has been used up. However, the driver also has the
option of controlling the four-cylinder Flexifuel engine manually
via a button in the instrument panel.
This allows the driver to start the engine earlier in order to
maximize battery charge, for instance when out on the highway in
order to save battery capacity for driving through the next town.
"There is a considerable difference between our plug-in hybrid and
today's hybrids. Today's hybrids use the battery only for short
periods to assist the combustion engine. Our solution is designed
for most people to run on electric power all the time, while
providing the extra security that comes with having a combustion
engine as a secondary source of electrical power," says Ichiro
Sugioka, project manager for the Volvo ReCharge Concept. He adds:
"What is more, our C30 with plug-in hybrid technology retains its
lively and sporty driving properties. Acceleration from 0-100 km/h
takes 9 seconds and top speed is 160 km/h."
Specially developed electric motors
The central electrical components in the Volvo ReCharge Concept
demonstrator - the generator for the APU and the wheel motors - were
developed together with British electromagnetic specialists PML
With an individual electric motor at each wheel, weight distribution
as well as mechanical efficiency and traction are maximized. The
friction in mechanical gears is eliminated. Since the car does not
have the transmission found in ordinary cars, there is no need for a
To help maximize the environmental benefits, the Volvo ReCharge
Concept has high-efficiency tyres developed by Michelin. They are
specially designed to accommodate the wheelmotors.
Further more, the car has All Wheel Drive in the truest sense of the
term. Power to each wheel is controlled individually.
The energy that is generated during braking is transmitted to the
battery pack. When the system is ultimately developed, traditional
wheel brakes will be completely replaced by electrical brakes with
minimal energy wasted through friction.
To ensure reliable operation of the drivetrain and braking system,
driver inputs are fed into a quadruple-redundant electronic control
Ecologically sound solution for commuters
The Volvo ReCharge Concept is best suited to car drivers who cover
moderate distances every day. For example, a commuter who has less
than 100 kilometres (62 miles) to drive between home and workplace
can cover the entire round trip on electric power alone and the
equivalent daily fuel economy will be zero litres per 100 km.
Even drivers who cover more than the battery-only range will benefit
from the ReCharge Concept. For a 150 km (93 mile) drive starting
with a full charge, the car will require less than 2.8 litres of
fuel, giving the car an effective fuel economy of 1.9 l/100km (124
"The only requirement is that the car owner has access to electrical
outlets at convenient places, such as at home or at the workplace. A
full recharge takes 3 hours. However, even a one-hour quick charge
should provide enough charge to drive about 50 kilometres," says