EVERYTHING YOU NEED TO KNOW ABOUT GREEN CARS

The main alternatives for green cars, based on the fuel type, are:

Gasoline - low CO2 emissions and high fuel economy gasoline engines are usually found in smaller cars.

Diesel - Diesel cars release less carbon dioxide than gas vehicles. They do have other emissions issues like particulate matter and NOx, which are harmful to the environment. Overall, diesels are considered to be more fuel efficient and have fewer emissions than gasoline vehicles.

Plug-in Electric -Technology has improved their power, capacity and range. These vehicles are classed as zero-emission vehicles.

Hybrids - Hybrids combine two power sources, usually an electric motor attached to either a diesel or a gas motor. Usually gas runs the vehicle when it's driving at high speeds and the electric power operates when the vehicle operates at lower speeds making it an ideal choice for city driving.

Biofuels - Biofuel usually means either biodiesel or ethanol. Biodiesel is made from a renewable resource such as canola or sunflowers. Sometimes, they can be used to replace diesel entirely. Ethanol is a grain alcohol that is made from grain plants. Gasoline and ethanol can be blended together for a greener fuel such as the popular E85 fuel.

Compressed Natural Gas- This is a fossil fuel with low CO2 emissions but is still classed as a greenhouse gas. Engine conversion is required to allow the vehicle to switch between this fuel and gasoline.

Propane or liquefied petroleum gas (LPG) -uses less CO2 than gasoline and emits less pollutants than diesel. Vehicles can be modified to run LPG.

Fuel Cells- Hydrogen is the main fuel cell in use. This is a green car alternative fuel source that is still being refined.

2008 Toyota Prius
EPA Combined Mileage: 46



2008 Honda Civic Hybrid
EPA Combined Mileage: 42



2008 Nissan Altima Hybrid
EPA Combined Mileage: 34



2008 Toyota Camry Hybrid
EPA Combined Mileage: 34



2008 MINI Cooper
EPA Combined Mileage:32



2008 MINI Cooper Clubman
EPA Combined Mileage: 32



2008 Toyota Yaris
EPA Combined Mileage: 32



2008 Honda Fit
EPA Combined Mileage: 31



2008 Toyota Corolla
EPA Combined Mileage:31



2008 Kia Rio
EPA Combined Mileage: 29



Top 10 Best Gas Mileage Cars for 2008

State and Federal Emissions Standards dictate how much of each type of pollution a car is allowed to emit into the environment. The amount of pollution allowed does not depend on the mileage your car gets but a car that burns twice as much gas to go a mile will generate approximately twice as much pollution. This pollution must be removed by the vehicles emissions control equipment. Decreasing the fuel consumption of the car is one way to decrease emissions.

There are several different standards that a vehicle can certify with. Where the vehicle is being sold and how clean it is in terms of fuel efficiency and emissions are the key issues.

In 2004, both the Federal and California Standards were updated. The Federal Standards now have Tier 2 standards which are tougher than the older Tier 1 standard. California has also introduced Phase II Low-emission vehicle standards as an update on their Phase I's.

The California standards are no longer just for vehicles being sold in California. Several other states have adopted the California standards as their own, including Maine, New York, Vermont and Massachusetts. Even more of the states are in the process of adopting these stricter standards for their own such as Connecticut, New Jersey, Pennsylvania, Washington, Oregon and even Rhodes Island

In all the other states, the vehicles are normally certified to the new Federal Tier 2 standards.

There are several methods available to identify which emission standard a specific vehicle is certified with. Some of these methods are:

• Check the manufacturer's web site for the vehicle specifications.


• Check the window sticker on the vehicle as it should identify the certification level.


• There is a mandatory label found just under the hood of every vehicle that identifies the emission standard.

There could be two certifications found as some vehicles will have both a Federal and a California certification. This allows the vehicle to be sold throughout the country. The process to identify certification isn't hard so do take the time to check it out.

You may also find a certification called 'clean fuel fleet' that is usually found on the under the hood label. This status is for regulatory purposes and shouldn't be used to identify the standards certificate. This regulatory certificate will not be as good as either of the California or Federal certificates.

Another incentive for auto makers to improve mileage are the legal requirements to meet Corporate Average Fuel Economy (CAFE) standards. Current standards require the average mileage of all new cars sold to be 27.5 mpg. This means that if an auto maker sells one hybrid car that gets 60 mpg, it can then sell four big, expensive, fuel inefficient, luxury cars that only get 20 mpg.

For more info see Autotropolis "What Green Buyers Should Know"

Everybody loves hybrids these days, and the poster-child of the hybrid generation is the Toyota Prius. But what is it about hybrids that is so great? Hybrids aim to reduce emissions whilst vastly improving fuel efficiency and this usually achieved by combining a regular gas tank and electric motor. A set of batteries provides electricity to the electric motor which powers the transmission and the wheels. These batteries usually get their power when the car is going at low speeds and a thing called regenerative braking ie. power is produced in normal lower speed braking situations.

The real genius of the hybrids is the power split device that connects the gasoline engine, generator and electric motor. It means:

• The electric motor can power the car by itself at low speeds, the gas engine can power the car by itself or they can power the car together.


• The power split device also allows the car to operate like a series hybrid.


• The gasoline engine can operate independently of the vehicle speed, charging the batteries or providing power to the wheels as needed.


• It also acts as a continuously variable transmission (CVT), eliminating the need for a manual or automatic transmission.


• Because the power split device allows the generator to start the engine, the car does not need a starter.


• The power split device is a planetary gear set. The electric motor is connected to the ring gear of the gear set. It is also directly connected to the differential, which drives the wheels. Whatever speed the electric motor and ring gear spin at determines the speed of the car.

For more info about Hybrids check out these articles:

What's New for 2009 - Hybrids by Autotropolis

Hybrid Cars by Autotropolis

Hybrid Cars.com - cool site with lots of info

Howstuffworks.com on Hybrid cars

Wikipedia's info about Hybrids

Hybridcarblog.com

There has been a resurgence in interest in diesel engines recently in the US, after the introduction of clean diesel technology by a number European manufacturers. The Europeans have long appreciated the efficiency and power of diesel vehicles, however the higher level of emissions have meant that they could not be introduced throughout the US.

In the last couple of years however the technology has been developed to reduce emissions to levels even lower than gasoline cars, and widespread introduction has been possible - even in California where emissions controls are amongst the toughest in the world.

Mercedes Benz has introduced its turbodiesel BLUE TEC engines in a number of its vehicles (including GL320, M320 and R320) and they are growing in popularity thanks to their brilliant fuel economy (up to 25mpg for the heavy M320) and vast torque available at low rpm (398lb-ft at just 1600rpm in the M320). Diesel engines are also renowned for their reliability and longevity and it is just another factor in their growing popularity.

The Volkswagen Jetta TDI has gained a clean diesel engine, and this year BMW also launches their Advanced Diesel with BluePerformance technology for the 335d sedan and xDrive35d. BMW claims that these new diesels perform with the power of a V8 with the efficiency of a four-cylinder thanks to the impressive 425lb-ft of torque at 1,750rpm. The 335d sedan is offering 36mpg on the highway which is as good as if not better than hybrid mileage, and it is expected that they will be eligible for the IRS Alternative Motor Vehicle Credit as Advanced Lean Burn Technology Vehicles.

Then there is BIO DIESEL.
Biodiesel is produced from natural oils like vegetable oils which removes the glycerine from the oil and leave behind biodiesel or methyl esters. It can be used in modified diesel engines or blended with regular diesel fuel up to 20%. B100 is pure biodiesel and B20 is the blended version. Overall it is less expensive than regular diesel and produces less sulphates, hydrocarbons and carbon monoxide. However it does produce more nitrogen oxide which requires aftertreatment (the same as what is used in the clean diesels).

Performance is comparable to regular clean diesel, with similar fuel economy and even better engine longevity thanks to increased lubrication. It is a simple process to convert diesel engines to biodiesel, and recent models may not need converting at all as many of the changes in the gaskets and rubber parts have already been made since the sulphur content of US diesel.

The issues of biodiesel have not yet been fully countered, and there is still problems with cold-weather starts, and the cost of adding catalytic converters for aftertreatment. In these cases B20 may be a better alternative where these issues are minimized.

There is a lot of talk about E85 engines that are equipped to use flex fuel. But what is it?

Flex fuel is an alcohol-fuel mix that can contain up to 85% ethanol (hence E85). Now many vehicles are being equipped with the ability to use E85 fuels, and the availability is increasing throughout the US. Flex fuel is usually a few cents cheaper at the pump, it burns with cleaner emissions and the ethanol comes from organic material like corn and sugarcane. However, many question the overall benefits of using E85 fuel for a few reasons:

• It is not as efficient, generates less power and gives less mileage.


• Although it is made from a renewable resource, the US is still having to import much of its ethanol from Brazil because of price competitiveness.


• Increasing production in the US means turning land that is producing a food resource over to biofuel production. In most cases this is in the form of corn, and so there is less corn available to food producers and the cost subsequently rises. Many argue that the cost benefit of the E85 fuel will be offset by the increased cost of food.


• There is evidence that the emissions produced by burning ethanol fuels which include formaldehyde and acetaldehyde are actually carcinogenic.


• Ethanol also contributes to ozone emissions.


• The actual production of ethanol consumes enormous quantities of energy and raw materials. Hundreds of gallons of water are needed for one gallon of fuel, and this also takes water out of the irrigation cycle and even from domestic use. Vast quantities of electricity, fuel and labour are required to get the ethanol to the stage of being useful, and transport costs are significant as it cannot be piped and must rely on rail and truck.


• Use of E85 fuel should be restricted to vehicles that are designed for flex fuel, otherwise damage to seals, fuel systems and exhaust systems is likely to occur and the cost of repair would far outweigh the savings in fuel costs.