Green vehicles are becoming increasingly popular. Since the early development of the market, Toyota has been an early adopter with its Prius model, but now there are many other companies producing fuel efficient cars. In the last few years there have been good improvements in both CO2 emission reduction and improved fuel economy. The majority of the improved CO2 results and gasoline savings from current vehicles is largely down to new technologies applied to vehicles.
One of the most recent developments is in the application of start-stop cars, which is an upcoming fuel saving technology. Actually the technology has been proven on larger commercial vehicles such as for public transport buses, where it was used in hybrid vehicles. These start-stop systems turn the engine off when the car comes to a stop, at lights or in a traffic queue, and then re-starts the engine when the car moves off again when the driver steps on the gas. This saves fuel, as a considerable amount of fuel is wasted while vehicles are sitting idling. A newer version of the start-stop engine control can now be used when the car is moving, for example when the car is coasting down a hill, again saving fuel which would normally be wasted. Start-stop system manufacturers estimate a saving of 10% when the system is used, which is a good saving for no impact on vehicle driving performance.
As technology keeps improving, other alternatives are open to manufacturers to make cars more environmentally-friendly. For example drive belts have been around for over a hundred years, but they are not very efficient as they are constantly turning accessories (such as alternators, air conditioners), whether they are being used or not. Now these accessories can be driven by electric motors which are only switched on when the accessory is actually needed. This is now an approved method, in fact the new Toyota Prius and the Ford Fusion have no drive belts installed at all.
Another recent trend is to get more power out of a smaller engine by using a turbocharger. Using a turbo booster can increase the output of an engine to boost fuel economy. The Ford Fiesta SFE uses a three cylinder Ecoboost engine to get 45 miles per gallon on the highway and 32 miles per gallon in urban driving. Ford now has over two million cars fitted with its Ecoboost gasoline direct injection engine. This shows a conventional engine can be greener without needing to be a hybrid vehicle. This has been recognized by manufacturers and in fact the use of turbochargers has increased by a factor of five times over the last five years.