Aims and Objectives Aim To be able to describe the operation of a vehicles hybrid system Objectives To recognize the need for alternative fuels To be able to describe the operation of a hybrid system To be able to comment on the use of hybrid systems Hybrid Vehicles

Why do we need alternative fuels? We need alternative fuels as our supply of fossil fuels (that make petrol and diesel) are becoming less and less. To make an effort to reduce our carbon footprint. To reduce the amount of harmful gases produced by vehicles. Hybrid Vehicles

Question In pairs discuss some other reasons why we might benefit from alternative fuels. Hybrid Vehicles

Alternative Fuels Ethanol Reduces the green house gases produced by vehicles, is commonly mixed with petrol to run motor vehicles:- E10 10% Ethanol 90% Petrol E85 85% Ethanol 15% Petrol (no difference in performance to the two) Hybrid Vehicles

Alternative Fuels Ethanol Plus points Lower Emissions More resistance to engine knock Added vehicle cost is minimal Ethanol Negative points Flex fuel vehicle Lower energy content Limited Availability Hybrid Vehicles

Alternative Fuels Bio Diesel Is made up of crops, or even old restaurant oil Can be used on its own or blended with petrol Hybrid Vehicles

Alternative Fuels Bio Diesel Plus points Can be utilised in most diesel engines Less air pollutants Biodegradable Non-toxic Safer to handle Bio Diesel Negative points May not be approved by the manufacture Lower fuel economy More nitrogen oxide Not suitable in lower temperature Concerns over engine durability Hybrid Vehicles

Alternative Fuels Natural Gas Can be used to fuel the car as a gas or a liquid Can be utilised within duel fuel vehicles Stored in high pressure tanks (therefore two fuelling systems are required within the vehicle) Hybrid Vehicles

Alternative Fuels Natural Gas Plus points 60-90% less smoke producing emissions 30-40% less Green House gasses emitted Less expensive Natural Gas Negative points Fewer miles per tank Less available Limited to the type of vehicles it is available on Hybrid Vehicles

Alternative Fuels Propane LPG Clean burning fossil fuel Contains fewer toxins Must have a separate fuelling system for the two fuels (petrol and LPG) Hybrid Vehicles

Alternative Fuels Propane Plus points Fewer toxins and smog emitting pollutants Less expensive Propane Negative points Not currently readily available on newer models Fewer miles available per tank of fuel Hybrid Vehicles

Alternative Fuels Hydrogen Hydrogen is been readily looked at as an alternative for petrol/diesel. Environmentally friendly fuel, however, there are challenges that stop this fuel being currently widely used. Hybrid Vehicles

Alternative Fuels Hydrogen Plus points Produced from several sources No air pollutants produced Produces only NOX Hydrogen Negative points Expensive Fuel cells can be expensive Lower energy density then fuel Hybrid Vehicles

Alternative Fuels Questions Give two advantages and disadvantages of hydrogen fuel? Hybrid Vehicles

Can be split into two sections:- Series and Parallel Series The vehicles Engine will drive the generator which in turn powers the vehicle. Parallel Engine and motor can be used to drive the vehicle, this system employs brake energy regeneration. This is the most favoured amongst manufactures. Hybrid Vehicles

Question What are the two sections that hybrid vehicles can be split into? Hybrid Vehicles

The main components include:- Motor High Voltage Battery Power drive Unit DC converter (direct current) Hybrid Vehicles

Toyota Prius Uses a Power Split system 1)the high voltage battery provides power to the motor to drive the wheels 2)Wheels are driven by engine to power splitting device. The generator is driven by planetary gears to provide the motor with electricity to drive the wheels 3)During de-acceleration energy is recovered at the wheels, the energy in converted to mechanical energy to charge the vehicles high voltage battery Hybrid Vehicles

Toyota Prius Power Splitter Is a epicycle gear box, that transmits energy in main components. Hybrid Vehicles

Toyota Prius 5 Operating Modes Hybrid Vehicles

Question Name one of the five modes that hybrid vehicles use. Hybrid Vehicles

Toyota Prius Start up Under normal conditions the motor will start the engine Under poor start up conditions the 12v starting system will start the vehicle Hybrid Vehicles

Toyota Prius Acceleration DC is converted to AC via the power drive unit This is used as supply to the motor It is also used to supplement engine output Hybrid Vehicles

Toyota Prius Cruise Engine drives the motor (which acts as a generator) The output current drives the motor Converted to 12v DC supplies the vehicles charging system Hybrid Vehicles

Toyota Prius Deceleration Motor is driven by the wheels under deceleration conditions, regeneration takes place Power drive unit converts AC current to DC current to charge the batter module. Some energy is then used to charge the 12v electrical system. If ABS senses wheel lock up, a signal is sent to the ECU and re-generation stops to prevent interference. Hybrid Vehicles

Toyota Prius Idle The flow of energy is similar to that of cruising If the charge of the battery is low, the ECU will raise the vehicles idle speed to compensate for this. Hybrid Vehicles

Summary - have we ? Recognized the need for alternative fuels ? Can we describe the operation of a hybrid system ? Are we able to comment on the use of hybrid system ? Hybrid Vehicles

Any Questions ? Hybrid Vehicles