HYBRID CARSIntroduction In an era where energy conservation has become the latest topicof discussion not only among the erudite but also among the ordinaryresponsible citizens, fuel efficiency along with minimum pollution hasbecome the benchmark for any new automobile. And in the same context “Hybrid Cars” come as the latestaddition. By the name itself it can be inferred that a hybrid car is animprovisation to the traditional gasoline engine run car combined withthe power of an electric motor.
As more and more people catch on to the wave of theautomotive future - the hybrid car, more and more questions ariseregarding these efficient, but somewhat mysterious vehicles. But justhow do they work, are they reliable enough, and are they capable ofbeing the car of the future?What is a Hybrid Car? A hybrid car is any car that combines two or more sources ofpower, such as gasoline and a rechargeable battery. A hybrid-electricvehicle (HEV) combines the power of a conventional internalcombustion engine with an electric motor. These dual engine systemscan be configured for different purposes such as increasing the car’spower and improving fuel economy. In fact, many people have probably owned a hybrid vehicle atsome point. For example, a mo-ped (a motorized pedal bike) is a type ofhybrid because it combines the power of a gasoline engine with thepedal power of its rider.Evolution of the Hybrid:
1839: First electric vehicle 1886: Electric powered taxicab in England 1900: Pieper introduced hybrid 1905: Gas-Electric car 1999: Honda Insight released in US (70 mpg) 2000: Toyota Prius available in US 2002: Honda Civic Hybrid introduced 2004: Toyota Prius II introduced; Ford Escape Hybrid introduced 2005: Lexus RX 400h Automobile 2006 model, 3MZ-FE V6 engine 2006: Toyota Camry Hybrid Automobile 2007 model, 2AZ-FXE engine
2009: Mercedes S400 Blue Hybrid(first lithium-ion battery hybrid and first Mercedes hybrid) Automobile 2010: Mazda Tribute Crossover
Why Hybrids? • Regenerative braking actually makes city driving more economical than on the highway. • Fuel efficiency is greatly increased (twice). • Emissions are greatly decreased. • Dependency on fossils fuels can be decreased. • Hybrids can be run on alternative fuels as well. • Emissions from vehicles are causing global warming and human sickness. • Natural gas extraction for the world will peak within a decade or two. • Hybrid vehicles produce much less emissions and use about 50% less fuel than the average new vehicle in the same class. (Partial- Zero emissions)Global-Warming: Still an Issue… • Hybrids are not zero-emission vehicles. • Will cut down emissions of global-warming pollutants by a third to a half. • Later models may cut these emissions down by even more.
Components of a Hybrid Car Gasoline Engine Fuel Tank Electric Motor Generator Batteries TransmissionHybrid car model:
Gasoline engine Much like our engines but smaller and is made with advanced technologies to reduce emissions and increase efficiency Fuel Tank Energy storing device for the gasoline engine Gas has a much larger density than the batteries Electric Motor Advance electronics allow it to act as either an motor or a generator. Ex: When needed it can take power from the batteries to accelerate the car. Generator Similar to an electric motor, just it acts only to produce electrical power Batteries Energy storage device for the electric motor Transmission Transmission on a hybrid performs the same as a transmission on our cars
How a transmission works is that it takes power from the engine or motor and sends to the driveshaft which turns your axle to move your carWhat makes it a "Hybrid"?Any vehicle is hybrid when it combines two or more sources of power.The gasoline-electric hybrid car is just that -- a cross between agasoline-powered car and an electric car. Lets start with a fewdiagrams to explain the differences.Figure 1 shows a gas-powered car. It has a fuel tank, which suppliesgasoline to the engine. The engine then turns a transmission, whichturns the wheels.
Figure 1. Gasoline-powered carFigure 2. Below shows an electric car, which has a set of batteries thatprovides electricity to an electric motor. The motor turns atransmission, and the transmission turns the wheels. Figure 2. Electric car
Hybrid StructureYou can combine the two power sources found in a hybrid car indifferent ways. One way, known as a parallel hybrid, has a fuel tank,which supplies gasoline to the engine. But it also has a set of batteriesthat supplies power to an electric motor. Both the engine and theelectric motor can turn the transmission at the same time, and thetransmission then turns the wheels.Figure 3 shows a typical parallel hybrid. Well notice that the fuel tankand gas engine connect to the transmission. The batteries and electricmotor also connect to the transmission independently. As a result, in aparallel hybrid, both the electric motor and the gas engine can providepropulsion power.
Figure 3. Parallel hybrid carBy contrast, in a series hybrid (Figure 4 below) the gasoline engineturns a generator, and the generator can either charge the batteries orpower an electric motor that drives the transmission. Thus, the gasolineengine never directly powers the vehicle.
HOW DO HYBRID CARS WORK?http://www.youtube.com/watch?v=LV2W36fPWngHybrid Performance: The key for the hybrid car is its ability to use a smaller engine A conventional engine is sized for peak power requirement whereas Hybrid engines are small. The hybrid engine is sized for running at the average power not the peak. But when it does reach that point that it needs help up a hill or to pass someone, it draws extra power from the batteries and the electric motor to get the job done.Hybrid Efficiency: Smaller Engines are more efficient Recovers energy and stores it into the batter Regenerative braking Sometimes it will shut the engine off
Hybrid Maintenance: Warranties: o The average warranty for a hybrid now is around either 8 yr/ 100,000 mile or even 10 year/ 150,000 mile Brake pads: No maintenance Batteries: o $6800 for new Toyota and Honda hybrid o But batteries tested to go for 180,000 miles and someAdvanced technology: Regenerative braking Electric motor drive/assist Automatic start/shutoffRegenerative braking: Recaptures kinetic energy normally lost as heat during braking. Electric motor acts as a generator when brakes are applied. Converts kinetic energy into electrical energy, stored in batteries.
Electric motor drive/assist: Additional power to assist engine accelerating, passing and up-hill driving. So, allows smaller and more efficient engine to be used. Automatic Start/Shutoff: Automatically shuts off the engine when the vehicle comes to a stop and restarts it when the accelerator is pressed. This prevents the accelerator is pressed.Some EPA (Environmental Protection Agency) facts: • Every gallon of gasoline your vehicle burns puts 20 pounds of CO 2 into the atmosphere. • A 5 mpg difference in fuel economy equates to about 2,800 pounds of CO2 a year.
Recent Advances:Revolution in Battery Technology: Today’s automotive starter batteries: Lead-acid RAV4 EV (and Toyota Prius hybrid battery): Nickel Metal-hydride New batteries based on Lithium, Li-ion or Li-polymer: 5x lighter for same energy! These advances make possible large battery storage for vehicles.BMW’s BRIGHT IDEA: BMW has emerged onto the hybrid gas-electric vehicle scenewith its X3 SUV that features super capacitors instead of batteries tostore energy. The “super caps” are located in the rocker panel area ofthe X3 to give it a low center of gravity.
Advantages: Excellent gas mileage Fewer tailpipe emissions Lighter batteries than electric vehicles Regenerative braking system stores electrical energy in batteries Uses less fuel to recharge batteries 20% -25% better mileage than ICE 30% reduction in emissionsDisadvantages: Reduced, but not emission-free HECs are partial zero-emission vehicles (PZEVs) – they produce zero emissions only when engine is not running More expensive than conventional Vehicles Has a payback period in average use Expensive Batteries are expensive and toxic waste
Current Models of HECs:•Chevrolet Volt•Honda Accord Hybrid•Honda Civic Hybrid•Ford Escape Hybrid•GMC Silverado Hybrid•GMC Sierra Hybrid•Toyota Prius•Toyota Highlander Hybrid•Honda InsightReferences: • www.howstuffworks.com • www.wikipedia.org • www.hybridcars.com • www.greencar.com • www.alternativefuels.about.com • Electric and Hybrid cars: A History by Judy Anderson • All About Electric and Hybrid Cars by Stephanie Bearce
CONCLUSION: • Present day automobiles, not only stress on power, performance & luxury, but also focus on emissions, efficiency & reliability. • The demand for fossil fuels will be at a critical stage in the coming future, resulting in high prices of fuels. • The present emission rates from the vehicles are so high that they add to the global warming. • There is a need for clean & less emission vehicles. • Hence, Hybrids are the vehicles of the future.