Car manufacturers are mired in an endless evolutionary maelstrom with the firm intention of giving greater benefits to their vehicles and being more respectful of the environment. The process initiated by Mazda Renesis rotary engine in its RX-8 model – which earned the award "Best International Engine of the Year in the Engine Expo 2003 Trade Fair” in Stuttgart – and the relentless search for an alternative to traditional fuels for restrict pollution by Carbon dioxide (CO2) released during the combustion engines of cars, and witness. Fulfilling the commitment made by industrialized countries in Kyoto (1997) reducing their emissions of greenhouse gases in the period 2008-2012, and the oil price increasing at the alarming decline of oil reserves are the main causes of a phenomenon that is revolutionizing the automobile market.
The rotary engine
With an output of 231 hp at 8200 rpm, weighing 124 kilograms and dimensions of 622×509 mm, the Renesis rotary engine, which Mazda is the only manufacturer worldwide, has its origins in the MSP-RE propellant, which was used in the prototype RX-01, exhibited at the Tokyo Motor Show in 1995.
Unlike a traditional engine, where the pressure of the expansion created by the ignition of the fuel-air mixture pushes the piston up and down within the cylinder – and the connecting rods and crankshaft convert, This linear motion in rotary – in a rotary engine, there is no linear movement to transform. The pressure is contained in chambers created by different areas of the housing and the convex surface of a triangular rotor. During combustion, the rotor turns immediately, an action that reduces vibration and increases the potential regime of engine speed. Thus, while the four-stroke engines the cylinder performs four different tasks – admission, compression, combustion and exhaust – on a rotating, each of these tasks are performed in a different area of the housing.
One of the innovations introduced in Renesis rotary engine is its location, behind the front axle, which is achieved by a balanced weight distribution front / rear and a low center of gravity. The objective is to acquire a dynamic to a stable and adequate capacity to respond to all sorts of circular tracks. The Mazda RX-8 meets the emission standards and provides a more efficient fuel consumption.
Presentation of Japan's Toyota Prius in December 1997 was a milestone in automotive technology, as it was the first time they had a public system of propulsion comprising a gasoline engine (aluminum) and one electric, which acted as a generator during deceleration and braking and recharge the batteries automatically. It was the birth of the hybrid engine.
Two years later, in the model Inshigt launched by Honda, which was the electric motor as an assistant intervened, the gasoline engine moved the car with or auxiliary support in the various phases of its operation (assist in accelerating or stopping the combustion engine, for example). It first entered the IMA (Integrated Motor Assist), which won an award from the International Engine of the Year Award (2000). Its next model, the revolutionary new Civic Hybrid, began in 2003 with a maximum output of 93 hp.
At present, both Honda (Accord, Civic and Insight) and Toyota (Prius, Highlander and Lexus RX400h), maintain a relentless struggle to achieve supremacy in the market for hybrids. However, Toyota will launch two new models in 2006: the Lexus GS 450h, a luxury saloon large, and the Camry, a family vehicle. Also, Ford plans to produce a hybrid version of its Escape SUV in the United States, while General Motors plans to sell hybrid heavy trucks from this year. Sedan, Nissan will market a hybrid, in the United States in 2006.
Among other qualities, hybrid engines emit 90 percent less CO2 and are more efficient than the diesel (for example, the Prius is capable of traveling a thousand kilometers without refueling), then take half of 5 liters per 100 kilometers.
Compressed Air Car
After twelve years of study, the engineer Guy Nègre has developed, through the financial holding company MDI (Moteur Development International), an engine that can become one of the greatest technological advances of this century. Its application to CAT's vehicles provides significant advantages in both its cost and its environmental value. The flexibility of the new system facilitates the adaptability of this range of vehicles to the various transportation needs, allowing the coexistence of mono power engines and motors for air-biscay energy, employing further fuel. Both engines incorporate a special system for refilling when the tank is empty, the driver can choose the type of fuel that will fill up by indications in board computer. The fuel used by bi-energy engine can be gasoline, diesel, biodiesel, gas, liquid gas, ecological fuel and alcohol.
Up to five different models have been designed to meet market requirements. The family version is characterized by its large space, which can fit up to six seats they can focus on different directions. The models are equipped with two seats, is designed exclusively for industrial use, urban or rural, and its key drivers would be small artisans, farmers and transporters, while the Pick-Up – with similar specificities – is aimed at lovers hiking and outdoor sports. Inspired by the London taxi, the other prototype, with six seats offers multiple advantages in ergonomics and comfort for both the passenger and the driver. These last three vehicles belonging to the range CityCAT's. Finally, the Minicat it's the car of the future to move around the cities, where the speed limit is 50 km / h. Their small size – it has three seats and the boot of a saloon – a car makes it easy to scroll through the cities. The five models reach a speed of 110 km / h, with a range of 200 to 300 miles, bearing 500 kilograms – except Minicat's, whose maximum load is 270 kgs. – And can be recharged in 4 hours during power grid or air stations in a record time of 3 minutes.
The air coming out the exhaust these cars are even cleaner than it entered since it is distilled prior to injection with an active carbon filter. In this way, the vehicle produces no pollution as urban air filters completely pure and ejected at a temperature between -15 º C to 0 º C, ie, helping to reduce the greenhouse effect.
The hydrogen propulsion system
Hydrogen is the lightest and most abundant in the universe, so that, as part of the life cycle, it is harmless to environment. Another of its many properties is that it can be easily transported and accumulated in both gaseous and frozen liquid. This gas, colorless and odorless, has a calorific value three times to about the energy contained in gasoline. Given these powers, hydrogen can be used both to supply some heating and as fuel for motor vehicles. Nevertheless, this element is rarely found in nature in pure state, it is mainly found in water (H2O) in the various hydrocarbons and other chemical compositions. This means that hydrogen is produced by exploiting conversion process. Currently there are over 600,000 million cubic meters of hydrogen worldwide. This is the primary hydrogen obtained, for example by reforming natural gas, or hydrogen side, which in turn is a result of, for example, the manufacture of electrolysis cloralcalina.
United States has become the main promoter of this type of energy applied to vehicles. From the Department of Energy under the Government has signed agreements for five years, a $ 88 million with General Motors – with a commitment to build a fleet of 40 vehicles with cells of energy – and another 70 million with DaimlerChysler for encourage the development of this technology and promote their knowledge.
At present, General Motors (HydroGen3 Zafira and Sequel), Ford (Focus C-Max H2), Honda (HondaFCX) and BMW (BMW 750hL is the first automobile mass produced with hydrogen) are working with prototypes very advanced, especially with regard to the safety of deposits – is highly flammable hydrogen – increased power and greater ability – the electric motor, tank and fuel cells take up more space than the mechanics of usual Car -.
However, there are still major drawbacks to market these vehicles. First, we need to invest billions of euros on a network of service stations and production facilities. In addition, current methods for hydrogen are very expensive and the batteries used in some prototypes are still too high, hence its high price.
“Three in one”: cars driven by gasoline, alcohol and gas
In mid-2004, General Motors and president of the Brazil , Luis Inacio Lula da Silva presented the Astra Multipower, a car whose novelty lay in the alternatives offered for supply: natural gas, alcohol, mixing alcohol and gasoline or with traditional gasoline.
New technology – developed by Bosch – is called "Tri Fuel" and is the heir of the former "flex fuel", which combine gasoline and alcohol at the same time and that General Motors continues building five vehicles sold in Brazil. With the new "Tri Fuel", the driver can choose the type of fuel with just pressing a button – even when the car is in motion – because the rear of the vehicle incorporates a conventional tank ready to receive any portion alcohol and gasoline, which adds a cylinder to store the gas, an element which, used alone, provides a range of 300 kilometers.
Mix alcohol and gasoline not only has significant environmental benefits, but poses a respite to the pockets of drivers – as General Motors, a car driven by a gas consumes 60 percent less fuel per kilometer than a powered by gasoline -. In addition, the government of Lula da Silva encouraged the purchase of such vehicles with tax incentives. For that reason, 17 percent of vehicles sold in this country consume alcohol.
Although most projects seem futuristic prototypes submitted by the various car manufacturers have a common denominator: not using gasoline or reducing their consumption to a minimum. While our cities are still moving cars powered by traditional fuels, the first step has already been taken: we can only wait for all these alternatives to mature and consolidate the market.
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