Electric cars were developed before the internal combustion engine. In later years there was ruthless competition.
In 1900 in US the traffic was nearly all horse drawn and there were very few cars.
In the 1930s, National City Lines, which was a partnership of General Motors, Firestone, and Standard Oil of California purchased many electric tram networks across USA to dismantle them and replace them with GM buses. The partnership was convicted of conspiring to monopolize the sale of equipment and supplies to their subsidiary companies.
Electric car, built by Thomas Parker in UK 1884
EV, or electric vehicle, should include rail, air, water, space, or land, but has become shorthand for electric road vehicles.
They are powered by an electric motor with the electricity coming from any source.
A hybrid vehicle has both battery and another energy source such as an internal or external combustion engine.
A diesel electric vehicle such as mine haul trucks, locomotives, submarines, or ships have a diesel motor driving a generator, that in turn drives and electric motor. They have no battery. The advantage is the high torque when the vehicle is starting and the elimination of expensive gear boxes. It is cheaper and more flexible than gears, especially for multiple wheels. Some ships use gas turbines to drive the generator. It is a good way of converting high revs to turn a slow propeller.
The electric motor can be AC or DC.
The power is usually measured in kW. 1 KW = 1.34 HP
Usually the DC output from a battery is changed to 3 phase AC to give better control of the motor speed. Some motors are universal which can use DC or AC.
A single electric motor can simply replace the normal petrol motor in your car.
The rear wheel drive Tesla has an electric motor for the two rear wheels.
The all-wheel drive models have another motor for the front two wheels.
Cars can be converted to electric by replacing the wheels or disk brakes with ones with electric motors in them.
Lola B09/60 (Drayson Racing)
Diesel electric hummer (using biodiesel to be environmental). Bit of fun, but too high to use on sloping ground. Source
An electric car does not have a gearbox. A petrol car has a differential ratio of 3:1. However as an electric motor is usually spinning faster than a petrol engine, it needs a lower gear. An electric car has a diff ratio of 5:1 or 10:1.
In a conversion from a petrol engine, it is often simplest to leave the gearbox in place and drive in 2nd or third gear. This way there is no need to change the diff gears.
If an electric motor is used at low revs, then the fan may be slow, and the motor may need extra cooling. The motor may not be as efficient at low revs. The gearbox also has a reverse gear which simplifies the electric controls.
An Australian company, Evans Electric, has developed a linear induction motor that can replace most sets of disk brakes. Each motor can supply 100 HP.
Evans in-hub motor
Mitsubishi have developed a similar in-wheel electric motor.
The first and still the cheapest are lead acid. But they are heavy and dangerous as they produce hydrogen and oxygen which can explode. EVs use deep cycle batteries that are expensive. They are 70-75% eficient. They must be replaced every 3 years.
Nickel metal hydride
Used in hybrids because they have a long life and the technology is regarded as mature. However the patent was owned by a consortium of US auto industry companies with the aim of stifling development of the electric car. This company only permitted the sale of small batteries for use in hybrid cars that still had a petrol motor. Ref
BASF now owns the patent.
Molten sodium and sulfur, Molten Lithium and sulfur, and molten potassium. The "zebra" battery uses a molten sodium chloroaluminate (NaAlCl4) as the electrolyte. They have high power densities/Kg, and can take thousands of rechrge cycles. They must be kept hot when operating. Ref.
Lithium ion batteries are not yet a mature technology so have further improvement possible. They are prone to fire if not charged properly. Their lifetime is relatively short with hundreds to a few thousand charge cycles.
Lion batteries use a lithium cobalt oxide cathode and a graphite anode.
The newer Lithium iron phosphate batteries are expected to last for at least 10+ years and 7000+ charge cycles.
Lithium-manganese spinel batteries from LG Chem are expected to last up to 40 years.
Lithium vanadium oxide are used in Subaru prototype G4e, doubling energy density.
Silicon nanowires, silicon nanoparticles,and tin nanoparticles promise several times the energy density in the anode, while composite and superlattice cathodes also promise significant density improvements. Wikipedia
The Mars opportunity Rover generates 140 watts from it PV cells and store the electricity in its lithium ion battery.
Charging (polymers of sulfur form at the cathode):
Motors can also act in reverse by generating electricity when the wheel drive the motor as in slowing down or braking. They can charge the battery thus recovering energy making EVs more efficient.
How many KM per kWh?
One kilowatt-hour of storage offers sufficient energy to travel approximately 4 km in a 1.5 T electric car, or 120 km on an electric bicycle.
Using coal fired mains power, electric vehicles produce about 50% less CO2 compared to petrol or diesel vehicles.
This will decrease to near zero if you use clean energy.
The Tesla S with a 60 kWh battery can drive 320 KM, with a 85 kWh battery, 510 KM
The average car drives 38 KM/day (14,000 KM/y). This would use 9 kWh/day.
A 1 KW PV cell generates about 4 KWh/day.
So a car would need a 2.25kWh rooftop PV to produce 9 kWh/d (3,000 kWh/y).
Each average house has about 2 adults and uses about 12 kWh/D - or 6 kWh/D/driver.
In a house with 2 cars, 2 car owners uses 18 kWh/day for cars, and 15 kWh/D for the house. Total = 33 kWh/D. (12,000 kWh/y)
So to generate enough for the house and the 2 cars you need 33 kWh per day. So without losses, you would need an 8 KW PV system.
Microgrid - car plugged into home
The standard Tesla has a battery capacity of 60 kWh.
With normal driving we use about 10 kWh during the day and return home with 50 kWh in the battery. For the evening we will need about 5 kWh to run the home.
We can easily run the house with this during the most expensive part of the day, then recharge during the night when power is cheap.
If there were 2 electric cars in a household, they could run the house and transport for 3.5 days.
The difficult part is charging the car with the PV cells during the day. Batteries are expensive.
EV and the grid
If everyone had an electric car, then our electricity consumption would be about double. If trucks and busses etc were electric also, our consumption would be more than double.
If most buildings generated and used their own electricity, then there would be no need to increase the size of our grid. It is probably about the right size now.
The average Australian car drives 14,000 KM/y and that will need about 3,000 kWh/y.
When battery prices drop, it will be possible to generate much of this with rooftop solar. Some work places, parking lots, etc. will install rooftop solar for charging cars during the day.
With so many variables, it is very difficult for power companies or governments to predict the power and grid requirements in the future.
The average wind turbine has a power capacity of 3 MW. A wind turbine will produce about 20 MWh per day (3 MW x 24 hours x 30% capacity) 7,200 MWh/y.
Enough for 900 car owners, including their household usage.
For 13 million private cars and homes we would need 14,500 3MW turbines.
At 0.1 Ha per turbine, the total land required for wind turbines would be 1,400 Ha
TYPICAL ELECTRICITY USE
Households with 1-2 residents use about 5,600 kWh/y
Households with 3-4 residents use about 8,400 kWh/Y
Further, residents of freestanding houses tend to use more electricity than residents of semi-detached dwellings and flats, .
Cost of energy for electric vehicles for 10,000 KM
Mileage Data: UDSOE
Efficiency of electric vs petrol / gasoline
Electric vehicles convert about 59%–62% of the electrical energy from the grid to power at the wheels
Petrol / gasoline vehicles only convert about 17%–21% of the energy stored in gasoline to power at the wheels.
So electric vehicle are bout 3 times more efficient.
Cost of petrol vehicles 10,000 KM