Electric Cars

An electric car consists of a battery, an electric motor, and a controller. The motor is powered by batteries by using the batteries’ electrical energy and converting it to kinetic energy. The controller regulates the energy flow to the electric motor. An electric car stores its energy on board in batteries. These batteries can be plugged into an electrical outlet or charged by another source such as a gasoline engine, fuel cells or solar power.
The two main types of electric cars are: “all electric” and hybrid. “All electric” cars run only on batteries and that are charged up by an electrical outlet. “All electric” cars are also only powered by the electric motor.
Out of Hybrid Electric Vehicles (HEVs) there are three types of drivetrains that are used in HEVs. The three types are the series drivetrain, the parallel drivetrain, and the series/parallel drivetrain. In the series drivetrain only the electric motor turns the wheels, while the batteries are charged by a gasoline engine. This system will be used in the Chevrolet Volt coming out in 2010. In the parallel drivetrain the gasoline engine and the electric motor combine to generate the power that turns the wheels. Major cars that use the parallel drivetrain are the Honda Civic, Accord and Insight. The series/parallel drivetrain uses the series type at lower speeds and the parallel type at higher speeds.
“All electric” cars are powered only by the electric motor. Unlike gasoline engines, an electric motor has only one rotating element. This is a power train of gears, shafts and motions that transit motion from the motor to the wheels. This simplicity in electric cars is an advantage because there is less to go break and need to be repaired. Most electric cars don’t have transmissions instead; the flow of electricity controls the motor. In order to go in reverse, the flow of electricity through the motor is reversed, which changes the rotation of the motor.

Electric Car Considerations

There is no doubt that electric cars can be built and sold major car companies. The question is can they be manufactured and sold for profit. Two other considerations with electric cars are their effect on the environment and the cost of creating the infrastructure needed to produce, repair and fuel electric cars.

Environmental

The electric car has always been promoted because of its positive effects environmentally. The most popular advantage is that “all-electric” cars produce no roadside emissions. Other advantages are that electric cars produce no smog, smoke, odor or noise. All electric cars reduce our dependence and use of foreign oil. This is because “all-electric” cars require no gasoline or oil to operate. Hybrids also raise mileage per gallon compared to gasoline cars. Therefore, even hybrids can highly reduce our use of foreign oil and the negativity surrounding it. Another advantage is that the only solid waste is the batteries. Also lead-acid batteries are 97% recyclable. Electric cars will continue to have a positive effect on our environment as they reduce and eliminate our roadside emissions.

Economics

There are many complaints surrounding the electric car and its economics. The myth is that electric cars are very expansive. This fact has been proven false by the price of 2009 Prius being $22,000. This is compared to the $21,000 for the new, and popular, Honda Accord. Another stat is that over 120,000 miles driven a 2009 Toyota Hybrid Camry will save about $4000 for fuel costs compared to its gasoline counterpart. Through this it is shown that the costs for a buyer make hybrid electric cars affordable. Unfortunately, “all-electric” cars costs for full production are still unknown. But, as the production of batteries continues to get cheaper the cost of producing “all-electric” cars will be affordable to the mass public. Economically, electric cars could help save our economy, because we will buy electricity from our own country rather than foreign oil.

Infrastructure

There are many problems and solutions to the infrastructure needed to produce and fuel electric cars. The technology to produce electric cars is already available and being used for electric cars. One problem with electric cars is fueling them quickly and conveniently. The first answer is that an electric car can be refueled almost anywhere with a 120 volt electric supply in electrical outlets. There are also increasing number 110 and 220 volt fast-rate charging stations being built. The technology is there to build charging stations but, the number of them built is still very low.
The other problem is where the electricity is getting produced from. Most electricity at the moment is produced in coal plants. But, coal plants still produce fewer emissions than gasoline engines. Also there is electricity produced from solar, wind and hydro power. There are worries that the current infrastructure could not support a whole country using electric cars. But, if most cars are charged during night the electric grid will not be overloaded. Also new coal plants could be built as well as an expansion in harnessing solar, wind and hydro power. The infrastructure doesn’t yet exist for a mass fleet of electric cars to be produced cheaply and then fueled with our electric grid. But, these problems could be solved with current technology in the near future.

Power Sources

The electric motor of a car can be powered by electricity from solar power, fuel cells, batteries or a gasoline generator. These different sources of electricity are currently being developed and used in electric cars.

Solar

It has always been the hope that electric cars could be solar-powered. Unfortunately, solar cells, also called photovoltaic cells, produce too little power. Therefore, they are impractible to power an electric car. Solar cells can be used to give additional power to an electric car, but they cannot be the main power source.

Fuel Cell

The fuel cell is a promising technology in powering electric cars. A fuel cell is an electrochemical cell in which the energy of a reaction between a fuel, such as liquid hydrogen, and an oxidant, such as liquid oxygen, is converted into electrical energy. The fuel cells being developed to power electric cars are ones reacting hydrogen and oxygen gas.
Fuel Cells are more efficient than an internal combustion engine. At best a gasoline engine is about 25% efficient, while fuel cells are approaching 40% efficiency. Fuel cells also produce no harmful emissions because fuel cells electrochemically convert the energy stored in hydrogen rather than combust it. Unfortunately, fuel cell automobiles won’t be available until at least 2015. This is because of the cost of hydrogen and the infrastructure for fueling cars with liquid or hydrogen gas.

Batteries

The most popular method for powering an electric car is batteries. The three main types of batteries used in electric cars are lead-acid, nickel metal hydride and lithium-ion batteries. The three battery types are used in electric cars varying in range and top speed.

Lead-Acid

Lead-Acid Batteries are the lowest cost type of electric batteries. Lead-Acid batteries are used in many ways. The batteries used in electric cars are called deep-cycle batteries and are rechargeable. Lead-Acid batteries have a low energy density which makes electric cars powered by lead-acid batteries have a low range because of an energy density at 2.55 kWh/ cubic ft. Also lead-acid batteries will only be able to survive about 600 cycles of 80% discharges before the batteries need to be replaced. Lead-Acid Batteries only cost about $140. Lead-Acid are the cheapest battery available to produce, but they also hold less energy and can be recharged less times than the other two main car batteries which are Lithium-Ion and Nickel-Metal Hydride

NiMH

Nickel-Metal Hydride Batteries are becoming the battery of choice in electric cars. This is because Nickel-Metal Hydride has an energy density of 4.96 kWh/ cubic ft and at a modest cost. The batteries’ energy density allows electric cars to go two times the range compared to lead-acid for the same battery size. Also Nickel-Metal Hydride batteries will only be able to survive 600 cycles of 80% discharges before the batteries need to be replaced. Nickel- Metal Hydride has a high energy density and amount of life cycles for a moderate price making it a popular option for today and the future.

Li-Ion

Lithium-Ion Batteries are the battery of the future, but they are also being used in cars now. Lithium-Ion Batteries are the long range battery of choice. This is because the batteries have a high energy density. They also have slow energy degradation and are light. This allows for the batteries to give the same range as lead-acid and NiMH batteries, while taking up less space then the other batteries.

Electric Cars in Production

There are many electric cars that have been or will be mass-produced. The four cars I will focus on are the Toyota Prius, GM EV1, Chevrolet Volt and Honda Insight. These four cars were and are major steps in building electric cars. The four cars include three hybrid electric vehicles and one all electric car. The three hybrids each have a different drivetrain than each other.

Toyota Prius

The Toyota Prius was introduced worldwide in 2001 as the first mass-produced hybrid vehicle sold worldwide. It is still being developed and manufactured by Toyota.
The 2009 version averages about 46 mpg which would make it the most fuel efficient car sold in the U.S. Unlike many electric vehicles the Prius has good amount of interior space. The Prius is only $ 22,000 which makes it an affordable HEV. The Prius uses the series/parallel drivetrain. The Prius also uses regenerative braking to recharge its batteries. Most reviews say that the negatives of the car are that the car is not much fun to drive. The positives are that the car has become a mainstream car with over 180,000 sales just last year. The Prius does what its buyers want which is to be comfortable and be highly fuel-efficient.

Chevrolet Volt

The Chevrolet Volt is scheduled to be to be released late in 2010. The Volt is unlike other hybrid cars in that the Volt operates its propulsion system only on electric power. The Volt is estimated to cost about $40,000 and get about 640 miles on a single12 gallon tank. The Chevrolet Volt uses the series drivetrain. The Volt would be the first hybrid to be mass-produced with the series drivetrain. The Volt also uses regenerative braking to recharge its batteries. The Volt will go about 40 miles on the charge in the batteries then it will get about 50 mpg when the gasoline generator gives power to the batteries. The Volt is good for the deep pocketed buyer looking to go green. But, until the ticket price gets cheaper the average American will not be buying the Volt. The Volt may be the future for hybrid electric vehicles, but the price tag isn’t low enough yet.

GM EV1

The GM EV1 was an “all-electric” car that was leased in 1996, but was discontinued in 1999. Then most of the EV1s were removed from the roads in 2003. The EV1 was originally leased with valve-regulated lead-acid batteries. These batteries were able to give 450 deep discharge cycles and could give a range of about 90 miles on a single charge. The cars were then given a NiHM in 1998 that doubled the range of the vehicle and gave 1800 deep discharge cycles before needing to be replaced. But, The NiMH batteries did cost 4 times more than the valve-regulated lead-acid batteries. With a charger designed for the EV1 the battery could be fully recharged in three hours. The EV1 was sold at a price of $33,995. The EV1 was a remarkable step for electric cars. But, because of the cost of the car and politics during the time the EV1 was unable to succeed.

Honda Insight

The first generation Honda Insight was a 2 door hatchback that was built from 2000 to 2006. The Insight was the first HEV sold in America. Honda has now announced a new 4 door hatchback that they will release in 2010. The 2010 version is estimated to be only $20,000 which compares favorably to other hybrids and is affordable for the average buyer looking for a new car. The Insight uses a parallel drive train. The Insight is similar to the Prius in that it gives a nice ride and is very fuel efficient.

Electric Car News - 11/10/2008

This is a news update on green cars and their technology.

Stirling Engine Hybrid - An article about Dean Kamen (inventor of the Segway) designing a hybrid car that utilizes a Stirling engine.
Ohio Teenager builds electric car - This is a story about an Ohio teenager who converted a gas powered car into an electric car using a commercially available kit.
Electric Car Battery Element - An article about the availability of lithium and the reserves in Bolivia.

T. Boone Pickens back Natural Gas for vehicles

This is an article on CNN.com of an interview with T. Boone Pickens who has a plan for increasing our distribution and use of Natural Gas as a power source for cars. - T. Boone Pickens Interview