新能源汽车英语讲稿

BMW Hydrogen 7
Natural gas and liquefied petroleum gas vehicle
Most of this kind of vehicle use double fuel system, namely a compressed natural gas or liquefied petroleum gas systems, and a gasoline or diesel combustion systems, can easily transition from one system to another system, this car is mainly used for urban public transport vehicles. Advantage: Gas single component, high purity, uniform mixing with air and burned completely, CO and particulate emissions are low, the engine starting at low temperature and better running performance. Disadvantage: Its transport performance is poor than the liquid fuel, low volumetric efficiency of the engine, the ignition delay is longer and dynamic decreased.
Hydrogen-powered Vehicle
Hydrogen-powered vehicle is a truly zeroemission vehicle, emissions of pure water, which has a non-polluting, zero emission, is the best alternative to conventional car. Advantage: source of hydrogen; the emission is water, no pollution. Disadvantage: The high manufacturing cost of hydrogen fuel cells, and hydrogen fuel storage and transport in accordance with the technical conditions is very difficult.
Summary
Today, energy shortages, environmental pollution is getting worse. clean energy vehicles have become the trend of the future development of the automotive industry. But the technology is not very mature. There are some problems in security, fast-charging, decline the cost, increasing the battery capacity.
Problem
1. Battery technology is not mature enough, car traveling a short distance with the battery, if add the battery, the weight of car will increase, the efficiency will decline. 2. Large current discharge easily result the battery heating, causing the battery to burn. 3. Short circuit the battery prone to explosion 4. Battery charging time is too long.
As the name implies the pure electric vehicles are the cars use electric power. Most of them use electric directly, also have some others use four wheels as the four motors’ rotors. Advantage: no exhaust, no pollution, technology is relatively simple and mature. Disadvantage: the energy stored in the battery unit weight too little, and the battery’ manufacturing cost is too high, some even more expensive than the car.
Hybrid Electric Vehicle
Hybrid electric vehicle refers to those using conventional fuels, but with the motor/engine to improve power output and low fuel consumption of the vehicle. Advantage: because of the battery, you can very easily recover braking, downhill, idle energy; when battery driven individually, to achieve "zero" emissions. Disadvantage: Mainly rely on fossil fuels, it’s just the products of the transitional period of new energy automotive.
Methanol-fueled car
Methanol vehicles is methanol as the primary fuel vehicles, but also use gasoline or gasolinealcohol mixed fuel as fuel, can be converted by the average car. Advantage: complete combustion, low volatility, emissions of hydrocarbons, nitrogen oxides and carbon monoxide and other harmful gases little. Disadvantage: Its lower energy with almost the same distance twice than gasoline consumption, which requires a large tank.
Fuel-cell Vehicle
Fuel-cell vehicle is that car use hydrogen or others as fuel, through the chemical reaction create electric current to drive the car. Advantage: Fuel-cell’s energy conversion rate is twice the internal combustion energy, or even higher; the chemical reaction progress of fuel-cell does not produce harmful exhaust; running smoothly, no noise, so the fuel-cell vehicle is a kind of ideal vehicle . Disadvantage: manufacturing cost is too high, current technology is difficult to achieve the industrialized.
The development trend of automobile industry
clean-energy vehicle
Classification
Development Status
Problems Summary
Classification
Pure Electric Vehicle Hybrid Electric Vehicle Fuel-cell Vehicle
clean-energy vehicle
Methanol-fueled car Natural gas and liquefied petroleum gas vehicle Hydrogenpowered Vehicle
Development Status
Pure Electric Vehicle