September 2014 VIAVISION SHAPING THE FUTURE OF MOBILITY. Sustainable Mobility. with Natural Gas. The CO 2 -friendly Alternative

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1 September 2014 VOLKSWAGEN SHAPING THE FUTURE OF MOBILITY Sustainable Mobility with Natural Gas The CO 2 -friendly Alternative

2 NATURAL GAS Index Interview with 2 Dr. Heinz-Jakob Neußer Natural Gas Family 3 Drive 4 Bright Outlook 7 Advantageous 8 Natural Gas as Part of the Drive and Fuel Strategy Dr. Heinz-Jakob Neußer on Volkswagen s Compressed Natural Gas (CNG) technology Imprint Edited by Volkswagen Aktiengesellschaft Konzernkommunikation Brieffach 1972, Wolfsburg Phone: +49 (0) Fax: +49 (0)5361/ V.i.S.d.P. (Person responsible according to the German press law) Stephan Grühsem, Leiter Konzernkommunikation; Pietro Zollino, Leiter Produktkommunikation Marke Volkswagen Editorial staff Susanne van den Bergh, Stefanie Huland, Volkswagen: Michael Franke, Tonio Vakalopoulos Contact: redaktion@viavision.org Published by Verlag Rommerskirchen GmbH & Co. KG Mainzer Straße 16-18, Rolandshof Remagen Phone: +49 (0)2228/ Printed by L.N. Schaffrath GmbH Marktweg 42-50, Geldern All images in this issue are approved for reprint, citing as their source. Dr. Heinz-Jakob Neußer, Board Member of Management for the Volkswagen Brand and Head of Powertrain Development of Volkswagen Group. Why does Volkswagen offer natural gas vehicles? Since natural gas releases about 25 percent less CO 2 during combustion than petrol, natural gas powered vehicles are a good, environmentally friendly alternative. In addition to our highly efficient TSI and TDI engines and our innovative electric drive systems, natural gas drive systems are an essential step towards Volks wagen reaching the statutory CO 2 requirement of 95 grams per kilometre. As an innovative automobile manufacturer, this variety enables us to offer our cus tomers a wide range of drives for the individual configuration of their Volkswagen. What is the advantage of natural gas vehicles for the customer? A customer choosing a natural gas vehicle receives a Volkswagen in which he experiences the comfort and driving pleasure familiar to him from a petrol, diesel or alternatively fuelled vehicle. In addition, he has the advantage of saving about half of his fuel costs. For example, during a trip should he not find any CNG filling station in the immediate vicinity, the car can be fuelled with petrol since each natural gas Volkswagen is also e quipped with a petrol tank. How has the market for natural gas vehicles developed in recent years? Sales of natural gas vehicles have increased in recent years by about 5o per cent at Volkswagen alone in 2o13 compared to the previous year. With almost 1oo,ooo natural gas vehicles on German roads, we are on the right path. The number of natural gas filling stations and in particular the share of biogas has increased significantly in recent years. The search for a natural gas filling station for the customer has become considerably easier. Besides the integration of service stations into navigation systems, the use of relevant apps for finding gas stations has become increasingly easy. 2

3 September 2014 NATURAL GAS FAMILY Natural Gas Family Volkswagens with CNG Natural gas as an alternative fuel is already available today and the technology is mature. This alternative is one of several possible ways to reduce CO 2 emissions. Therefore, Volkswagen constantly extends the range of its vehicles with CNG models and thus continuously reduces the CO 2 emissions of its vehicle fleet. eco up! Golf TGI BlueMotion Engine: 1.0 litre, 50 kilowatt Engine: 1.4 litre, 81 kilowatt CNG* range: 380 kilometres CNG* range: 420 kilometres Petrol range: 220 kilometres Petrol range: 940 kilometres CNG consumption: 2.9 kilograms per 100 kilometres CNG consumption: 3.5 kilograms per 100 kilometres CO 2 emissions: 79 grams per kilometre CO 2 emissions: 94 grams per kilometre Caddy EcoFuel Touran TGI BlueMotion Engine: 2.0 litre, 80 kilowatt Engine: 1.4 litre, 110 kilowatt CNG* range: 450 to 630 kilometres CNG* range: 380 to 510 kilometres Petrol range: 150 kilometres Petrol range: 170 kilometres CNG consumption: 5.7 kilograms per 100 kilometres CNG consumption: 4.7 kilograms per 100 kilometres CO 2 emissions: 156 grams per kilometre CO 2 emissions: 128 grams per kilometre All data according to the New European Driving Cycle * with high calorific gas 3

4 NATURAL GAS DRIVE Drive The requirements for gas drives In order to operate a car with gas, it is advisable to change the construction of the drive train. Compared to petrol, gas has a more favourable ratio of hydrogen to carbon in terms of calorific value so about a quarter less CO 2 is produced. Due to the high octane rating (RON 13o) of natural gas (Compressed Natural Gas or CNG for short), even earlier ignition timings can be selected to increase efficiency, leading to higher pressure and higher component temperatures than that of a conventional combustion engine. Valve Train Camshaft Valve Shaft Seal Spark Plug Valve Seat Ring Valve Guide The materials of the inlet and exhaust valves, their guides and seat rings are adapted to the lower lubricity of CNG compared to liquid fuels. The valve stems are nitrated, that is treated with nitrogen to harden their surface. At the end of this process, their surface is heat resistant up to about 5oo degrees Celsius. The valve disc and the valve seat inserts in the cylinder head are armoured and the guide on the discharge side sintered a process in which the material is heated under high pressure to just below its melting temperature. Gas Specific Components Electronic Gas Pressure Regulator Gas Inlet Valves Gas Line Pressure/Temperature Sensor The high pressure gas stored in the tank must be led to combustion at a lower pressure. The electronic gas pressure regulator reduces the pressure in two stages, first from 2oo bar to 2o-25 bar, then to 5-9 bar. This pressure reduction significantly cools down the gas pressure regulator. To ensure that the temperature does not fall below minus 4o degrees Celsius, the gas pressure regulator is integrated into the coolant circuit. The inlet manifold has special mounting points for the injection valves because gas, in contrast to petrol, is not injected directly into the cylinder but via the inlet manifold. 4

5 September 2014 NATURAL GAS DRIVE Pistons and Crank Drive Pistons and Piston Rings Connecting Rod Bearing Shells The pistons are reinforced. They now weigh 33 grams more, including the bolts. The crank shaft, which transmits power to the vehicle axle, is also designed to handle increased pressure and higher temperatures. Therefore, every first piston ring groove is hard anodized a process in which a layer of aluminium oxide forms on the surface of aluminium components. The first piston ring is coated, the second chromed. Three-component shell bearings are used for the connecting rod bearing shells in order to cope with the higher pressure level. Exhaust Gas Turbocharger and Catalytic Converter Exhaust Gas Turbocharger Catalytic Converter The exhaust gas turbocharger is adapted for CNG oper ation in order to achieve a fast response time despite the lower volume and lower thermal energy of the exhaust gas. For that reason, the compressor wheel which is responsible for compressing air has been scaled down. Thus, in CNG operation it achieves a good response at low engine speeds. The turbocharger is designed for exhaust gas temperatures up to 95o degrees Celsius. Because methane reacts with oxygen at higher temperatures than petrol does, it made sense to change the catalytic converter as well. For this it is laden with a clearly defined composition of precious metals. 5

6 NATURAL GAS DRIVE Fuel Tank The two gas tanks are installed under the boot on the underbody of the Golf TGI, the petrol tank is unchanged in front of the rear axle. The gas tanks are made of steel and store the gas at a pressure of 2oo bar, a maximum of 97 litres or about 15 kilograms of CNG may be refuelled. The tanks are secured by a thermal fuse that triggers at 11o degrees Celsius, and an electrical shutoff valve, a pipe rupture fuse and a mechanical shutoff valve. The natural gas tanks are extensively tested during development. These tests include, among others, burst tests, in which the tanks are exposed to pressure several times higher than occurs during normal operation. Moreover, the controlled venting of the gas in extreme situations is demonstrated in fire exposure and bombardment experiments. In the latter, a projectile measuring nearly eight millimetres is shot at the tank. The test is passed if the tank does not burst and no fragments chip off. The durability of the tank is 2o years, no additional maintenance is required. Engine Control Unit In addition to its regular tasks, the engine control unit in a CNG vehicle must also manage the gas injection valves and electronic gas pressure regulator. It measures the pressure and the temperature of the gas. It then calculates the mass of the gas more precisely than previous methods. In addition, the engine control unit uses the exhaust gas oxygen sensor to monitor the quality of the natural gas and adjusts the injection time accordingly. Natural gas is available in two grades at the service station: H-gas (high calorific gas) has a high methane content of at least 87 percent, L-gas (low calorific gas), however, contains between 8o and 87 percent methane. The higher the methane concentration, the lower the fuel consumption resulting in greater range. Dual operation CNG vehicles can be fuelled by gas or petrol, to ensure the car has a good range. The engine must therefore run cleanly in both modes, so that the driver does not notice the switch from petrol to gas or the other way around. To achieve the same engine response in CNG operation as in petrol mode, the boost pressure is raised slightly in CNG operation and an earlier ignition timer is set. The vehicle starts up with petrol after refuelling gas as well as at very low temperatures (below minus 1o degrees Celsius) because the injection valves for the gas must first be heated to operating temperature. 6

7 September 2014 NATURAL GAS Good Outlook The Market for Natural Gas in Germany Grows Most agree that global greenhouse gas emissions must be lowered. The new car fleet is planned to emit an average of 95 grams of CO 2 per kilometre driven by 2o2o. Natural gas vehicles are a step in this direction: CO 2 emissions are lowered with every newly registered car. Continuous Growth Service Stations Vehicles n Number of service stations n Number of cars , n Number of car models 90, , , , , , , , , The market for natural gas in Germany is growing slowly but steadily: the number of registered cars as well as the number of car models increased by a factor of five in the last ten years, the number of gas service stations in Germany has almost doubled. Biogas in different concentrations is available at almost a quarter of service stations. Biogas is produced from renewable raw and waste materials as well as biodegradable waste and has, net, almost zero carbon emissions. 7

8 NATURAL GAS Advantageous Natural Gas Compared to Other Fuels Natural gas vehicles offer many advantages, however the most important one cannot be seen: the significantly lower CO 2 emissions. Another advantage will only be noticed by the driver after a longer period. Natural gas as fuel receives tax benefits and the consumption of the CNG vehicle lies significantly below that of a car with a conventional diesel or petrol engine. Energy content: (per litre or kilogram CNG) Cost: (per litre petrol or petrol equivalent) LPG* 6.9 kilowatt-hours Euro Petrol Diesel 9.8 CNG 13.7 LPG* Petrol Diesel CNG Natural gas has a higher energy content than other fuels, a kilogram is equivalent to about 1.5 litres of petrol or 1.3 litres of diesel. Converting the price of natural gas (including tax benefits) to one litre, leads to a much cheaper price compared with petrol or diesel. The tax benefits for natural gas will remain until 2018 and the German government plans to extend it as part of the coalition agreement. Faster, further, cheaper Distance in metres after...1 second...2 seconds...3 seconds 1.2 litre 77 kilowatts TSI litre 81 kilowatts TGI litre 90 kilowatts TSI Fuel Costs 7.50/100 kilometres (A / litre) 3.80/100 kilometres (A / kilogram) 8.10/100 kilometres (A / litre) Comparing the natural gas variant of the Golf, the TGI, to its similarly powered, petrol-fuelled brothers, shows that its consumption is significantly cheaper. The driver barely needs to compromise acceleration for efficiency. * LPG= Liquefied Petroleum Gas 8