Alternate energy sources for vehicles

1. SNIST (JNTUH)-M.TECH (THERMAL ENGG.)
ALTERNATE ENERGY SOURCES
FOR VEHICLES
Dr. SIRIVELLA VIJAYA BHASKAR
M.Tech(Mech)., Ph.D(Mech)., Ph.D(Mgmt)
Professor in Mechanical
Engineering

2. TOPICS
Introduction to alternate energy
sources for Vehicles like
 Electric vehicle (EV)
 Hybrid
 Fuel cell and
 Solar cars

3. ELECTRICAL VEHICLE (EV)
 An electric vehicle, also called an EV, uses one
or more electric motors or traction motors for
propulsion.
 An electric vehicle may be powered through a
collector system by electricity from off-vehicle
sources, or may be self-contained with a
battery, solar panels or an electric generator to
convert fuel to electricity.
 EVs include, but are not limited to, road and
rail vehicles, surface and underwater vessels,
electric aircraft and electric spacecraft.
 A major feature of EVs is that drivers can plug
them in to charge from an off-board electric
power source to Charge battery which is
source of electric energy.

4. ELECTRICAL VEHICLE (EV)
The heart of an electric car is the combination of:
 The electric motor
 The motor's controller
 The batteries
 The controller takes power from the batteries and delivers it to the
motor.
 The accelerator pedal hooks to a pair of potentiometers (variable
resistors), and these potentiometers provide the signal that tells the
controller how much power it is supposed to deliver.
 The controller can deliver zero power (when the car is stopped), full
power (when the driver floors the accelerator pedal), or any power
level in between.

5. Motor
Controller
Charger
DC/AC Converter
Batteries
PARTS OF EV
• The major problem with EVs is low storage capacity of Battery
and so can be used for Short distances ranging from 80-100
Kms.
• Charging time battery is more. It is almost more than ONE
Hour

6. HYBRID VEHICLE
 A hybrid vehicle combines any two power (energy)
sources.
 Possible combinations include diesel/electric,
gasoline/fly wheel, and fuel cell (FC)/battery.
 Typically, one energy source is storage, and the other
is conversion of a fuel to energy.
 The combination of two power sources may support
two separate propulsion systems. Thus to be a True
hybrid, the vehicle must have at least two modes of
propulsion.

7.  For example, a truck that uses a diesel to drive a
generator, which in turn drives several electrical
motors for all-wheel drive, is not a hybrid . But if the
truck has electrical energy storage to provide a
second mode, which is electrical assists, then it is a
hybrid Vehicle.
 These two power sources may be paired in series,
meaning that the gas engine charges the batteries
of an electric motor that powers the car, or in
parallel, with both mechanisms driving the car
directly.

8. HYBRID ELECTRIC VEHICLE (HEV)

9. ELECTRICAL VS. HYBRID VS. SI VEHICLES

10. HYBRID ELECTRIC VEHICLE (HEV)
 As shown in Figure, a HEV is formed by merging
components from a pure electrical vehicle and a pure
gasoline vehicle.
 The Electric Vehicle (EV) has an Motor Generator (M/G)
which allows regenerative braking for an EV; the M/G
installed in the HEV enables regenerative braking.
 For the HEV, the M/G is tucked directly behind the
engine. In Honda hybrids, the M/G is connected directly
to the engine. The transmission appears next in line.
This arrangement has two torque producers; the M/G in
motor mode, M-mode, and the gasoline engine.
 The battery and M/G are connected electrically.

11. FUEL CELL
 Fuel cells are devices that produce electrical energy
through electrochemical processes, without
 combusting fuel and
 generating pollution of the environment
Basic Concepts:
 The core structure of a generic fuel cell includes
two thin electrodes (anode and cathode), located
on the opposite sides of an electrolyte layer

12.  Hydrogen is the basic fuel, but fuel cells also require oxygen.
One great appeal of fuel cells is that they generate electricity
with very little pollution–much of the hydrogen and oxygen
used in generating electricity ultimately combine to form a
harmless byproduct, namely water

14. FUEL CELL
 Hydrogen atoms enter a fuel cell at the anode where a
chemical reaction strips them of their electrons. The
hydrogen atoms are now "ionized," and carry a
positive electrical charge.
 Oxygen enters the fuel cell at the cathode and, in
some cell types (like the one illustrated above), it there
combines with electrons returning from the electrical
circuit and hydrogen ions that have traveled through
the electrolyte from the anode.
 In other cell types the oxygen picks up electrons and
then travels through the electrolyte to the anode,
where it combines with hydrogen ions.

15. FUEL CELL
 The electrolyte plays a key role. It must permit only the
appropriate ions to pass between the anode and
cathode. If free electrons or other substances could
travel through the electrolyte, they would disrupt the
chemical reaction.
 Whether they combine at anode or cathode, together
hydrogen and oxygen form water, which drains from the
cell.
 As long as a fuel cell is supplied with hydrogen and
oxygen, it will generate electricity

16. DIFFERENT TYPES OF FUEL CELLS
 Alkali fuel cells operate on compressed
hydrogen and oxygen. They generally use a
solution of potassium hydroxide (chemically,
KOH) in water as their electrolyte. Efficiency
is about 70 percent, and operating
temperature is 150 to 200 degrees C, (about
300 to 400 degrees F). Cell output ranges
from 300 watts (W) to 5 kilowatts (kW).
 Alkali cells were used in Apollo spacecraft to
provide both electricity and drinking water.
They require pure hydrogen fuel, however,
and their platinum electrode catalysts are
expensive. And like any container filled with
liquid, they can leak

17. MOLTEN CARBONATE FUEL CELLS (MCFC)
 Molten Carbonate fuel cells (MCFC) use high-
temperature compounds of salt (like sodium or
magnesium) carbonates (chemically, CO3) as the
electrolyte. Efficiency ranges from 60 to 80 percent,
and operating temperature is about 650 degrees C
(1,200 degrees F).
 Units with output up to 2 megawatts (MW) have been
constructed, and designs exist for units up to 100 MW.
The high temperature limits damage from carbon
monoxide "poisoning" of the cell and waste heat can
be recycled to make additional electricity. Their nickel
electrode-catalysts are inexpensive compared to the
platinum used in other cells.
 But the high temperature also limits the materials and
safe uses of MCFCs–they would probably be too hot
for home use.
 Also, carbonate ions from the electrolyte are used up
in the reactions, making it necessary to inject carbon
dioxide to compensate.

18. SOLID OXIDE FUEL CELLS (SOFC)
 Solid Oxide fuel cells (SOFC) use a hard,
ceramic compound of metal (like
calcium or zirconium) oxides (chemically, O2)
as electrolyte.
 Efficiency is about 60 percent, and operating
temperatures are about 1,000 degrees C (about
1,800 degrees F). Cells output is up to 100 kW.
 At such high temperatures a reformer is not
required to extract hydrogen from the fuel, and
waste heat can be recycled to make additional
electricity.
 However, the high temperature limits applications
of SOFC units and they tend to be rather large.
While solid electrolytes cannot leak, they can
crack.

19. SOLAR CARS
 Solar cars harness energy from the sun, converting it
into electricity. That electricity then fuels the battery that
runs the car's motor. Instead of using a battery, some
solar cars direct the power straight to an electric motor
 Solar cars can accomplish this through photovoltaic
cells (PVC). PVCs are the components in solar
paneling that convert the sun's energy to electricity.
They're made up of semiconductors, usually made of
silicon, that absorb the light.
 The sunlight's energy then frees electrons in the
semiconductors, creating a flow of electrons.
 That flow generates the electricity that powers the
battery or the specialized car motor in solar cars.

22. SOLAR ARRAY
 The solar array is the vehicle's only
source of power during the cross-country
Race. The array is made up of many
(often several hundred) photovoltaic
solar cells.

23. POWER TRACKERS
Power trackers condition the electricity coming from
the solar array to maximize the power and deliver it
either to the batteries for storage or to the motor
controller for propulsion.
When the solar array is charging the batteries, the power
trackers help to protect the batteries from being
damaged byovercharging.
The number of power trackers used in a solar car varies
with each team's design.
Power trackers can be very lightweight and commonly
reach efficiencies above 95%.

24. ELECTRIC MOTOR
An electric motor is the basic and the most important
ipart of a solar car.
It shoumpold work with optimal power and the efficiency
should be high.
An electric motor is a device using electrical energy to
produce mechanical energy, nearly always by the
interaction of magnetic fields and current-carrying
conductors.

25. SPEED CONTROLLER
The purpose of a motor speed controller is to take a
signal representing the demanded speed, and to
drive a motor at that speed. The controller may or
may not actually measure the speed of the motor.
 CHASSIS
The primary challenge in developing an effective
solar car chassis is to maximize the strength and
safety, but minimize the weight.
However, safety is a primary concern and the
chassis must meet stringent strength and
safety requirements.

26. BATTERY
 Battery is the main power supply of a vehicle.
 A battery is a device that stores chemical energy and
makes it available in an electrical form.
 Recently Lithium batteries are most widely used, because
it has extremely long cycle life and high discharge and
recharge rates than traditional batteries.