Press Release
Development in record time: BMW H2R
The power, performance and the liability of the engine concept were all impressively proven during the development phase, with the BMW H2R World Speed Record Hydrogen Car clearly proving the exceptional potential of this technology on a race track as early as in September 2004: Raced on the high speed track in the French town of Miramas, H2R broke no less than nine international records for hydrogen drive cars with a combustion engine, the test car powered by a 6.0-litre V12 hydrogen combustion engine achieving a top speed of more than 300 km/h and setting up new records for the distance of one kilometre with a flying start and the quarter-mile with a standing start. Acceleration from 0–100 km/, in turn, came in just 6 seconds.
Hydrogen tank: compact instead of all-round insulation
The dual-mode drive concept of BMW Hydrogen 7 requires not only suitable engine management and fuel supply, but also proper integration of two separate fuel tanks: To offer the longest conceivable cruising range, BMW Hydrogen 7 comes with both a conventional 74-litre gasoline tank and an additional fuel tank taking up approximately 8 kilos of liquid hydrogen.
This hydrogen tank is a key component of the hydrogen car, with the BMW Group being supported in the implementation of hydrogen technology in the automobile by Magna Steyr as an important partner in development. The hydrogen tank is made up of a double-wall tank structure consisting of two-millimetre-thick stainless steel plates and featuring a 30-millimetre-thick vacuum super-insulation layer between the inner and outer tank.
This configuration reduces heat transfer to a minimum, the interim layer offering the same insulating effect as approximately 17 metres or 56 feet of styropor. The connection pieces between the inner and outer tanks, in turn, are made of carbon-fibre bands reducing the conduction of heat to a minimum.
The insulation technology developed for the hydrogen tank in BMW Hydrogen 7 ensures a standard of temperature consistency never seen before in practice. A simple example is that if a tank of this kind were filled, say, with boiling coffee, the coffee would remain hot for more than 80 days before cooling down to a temperature suitable for drinking.
A consistently cold temperature is maintained in exactly the same way with the same supreme effect: Highly effective insulation serves to keep liquid hydrogen at a pressure of 3–5 bar and at a consistent temperature of approximately – 250 °C over a long period. The infusion of heat causing hydrogen to evaporate is very small indeed, and any loss of hydrogen resulting from the increase in pressure caused by higher temperatures is controlled with maximum efficiency by boil-off management limiting the inner pressure within the tank and ensuring controlled purge of hydrogen already evaporated.
Gaseous hydrogen able to escape in this way is diluted in a venturi pipe and oxidated in a catalyst to form vapour. The period in which a half-full hydrogen tank will be emptied completely in a controlled process is about 9 days, and even then the car is still able to cover approximately 20 kilometres or 12 miles in the hydrogen mode with the fuel remaining in the tank.
While driving, defined conversion of liquid into gaseous hydrogen forms a permanent, ongoing process, with hydrogen being removed from the tank in gaseous condition and fed to the fuel mixing and supply system. Precisely for this reason liquid hydrogen is evaporated in a specific, controlled process within the tan, building up a gas “cushion” under defined pressure.
Gaseous hydrogen extracted from the tank has to be warmed up for the subsequent fuel mixing process, using heat from the engine’s coolant circuit for this purpose. This heat is generated by a system of two interacting heat exchangers, the heat exchanger in the so-called secondary system capsule (SSC) receiving its heat from the engine’s cooling circuit and delivering this heat, first, via the second heat exchanger to the hydrogen tank and, second, to the hydrogen itself warmed up for the subsequent fuel mixing process.
Filling the tank in a process standardised worldwide
After manually connecting the tank pump coupling, the hydrogen tank is filled up automatically without any intervention on the part of the driver. So all the driver has to do is open the tank filler flap by pressing a button in the cockpit. Then he connects the tank filling coupling to the fuel tank cap simply by interlinking the two components with one another, the subsequent process of filling up the tank being completed automatically in about eight minutes.
BMW’s engineers have developed a standardised tank coupling for all liquid hydrogen filling stations the world over. This tank filler has been engineered in close cooperation between car makers, fuel supply companies, and the German company Linde with the technical know-how required for the generation, distribution and use of hydrogen.
The European automotive industry was represented in this joint development by the BMW Group, ensuring a worldwide technical standard for liquid hydrogen filling systems. Gasoline is filled into BMW Hydrogen 7 in the same way as on a conventional car, and the twelve-cylinder power unit is configured for premium plus fuel.
The driver can check the fuel level and the remaining range on both fuel systems simply by pressing a button in the direction indicator lever, the levels measured then being shown in the cockpit display beneath the speedometer.
The driver is able to switch from hydrogen to gasoline manually by way of a separate button in the multifunction steering wheel – and with both engine power and torque remaining exactly the same regardless of the mode of operation, switching over from one mode to another has no effect on the driving behaviour and performance of BMW Hydrogen 7.
While driving in the hydrogen mode, the display presents not the outside temperature and the time of day, but rather the chemical symbol for molecular hydrogen: H2, thus showing the driver quite clearly that the car is currently running on hydrogen fuel.
The operation control system in BMW Hydrogen 7 gives priority to the use of hydrogen, with the engine always starting in the hydrogen mode in order to minimise CO and HC emissions during the warm-up phase until the catalyst has reached its normal operating temperature.
This configuration serves to further improve exhaust emissions to an even higher standard. And should one of the two types of fuel be fully consumed, the system will automatically switch over to the other type of fuel in the interest of secure, ongoing supply.
Modified where necessary: chassis, suspension, and body
BMW Hydrogen 7 comes as standard on 8J x 18 light-alloy wheels and is available as an option with 19-inch light-alloy wheels including a BMW Mobility Set. All 18-inch tyres, whether summer or winter, are failsafe tyres. This means that the driver can go on even under complete loss of tyres pressure, driving to the nearest workshop without any hassle.
Yet a further feature is that a new generation of the TPC Tyre Pressure Control system permanently monitors the car’s wheels. Integrated in the valves of all four wheels, the TPC sensors register even minor deviations from the ideal tyre pressure, thus recognising the risk of a flat in good time even with only a gradual loss of pressure.
Accommodation of additional components in the rear end of the car called for re-alignment of the suspension and damping systems in BMW Hydrogen 7. So despite the higher load on the rear axle, both driving stability and motoring comfort remain at an optimum standard. And yet a further feature is BMW’s electronic AdaptiveDrive anti-roll stability system with continuously adjustable dampers featured as standard in BMW Hydrogen 7 and naturally specially tailored to the car.
The bodyshell of BMW Hydrogen 7 has likewise been modified exactly where required in order to set off the increase in weight resulting from this new drive technology and at the same time fulfil all demands in terms of passive safety. Use of carbon-fibre-reinforced plastic (CFP), for example, ensures an even higher level of crash strength and safety with only a minimum increase in weight.
Focusing especially on BMW Hydrogen 7, BMW’s engineers have furthermore developed an innovative combined CFP/steel body structure, with the sideframes right and left being reinforced all round by CFP in order to give the bodyshell additional strength and stiffness.
A particular feature of the car truly catching the eye from the very beginning is the engine compartment lid characterised in its contours by a distinctive powerdome. This change in design is indeed essential due to the greater height of the engine compared with a conventional twelve-cylinder – and at the same time it is a clear indication of the unique power unit beneath the engine lid.
Luxury class comfort for four
Given the position of the hydrogen tank beneath the parcel shelf and behind the rear seats, BMW Hydrogen 7 had to be modified at the rear, with luggage compartment capacity being reduced in the process to 225 litres. And on account of the car’s overall package, the centre armrest is fitted firmly at the rear.
Precisely this is why BMW Hydrogen 7 is conceived as a four-seater, the two passengers at the rear enjoying the same high standard of grand touring comfort in the world’s first hydrogen car developed for everyday use as in one of BMW’s “regular” luxury performance saloons.
The rear seat bench, for example, is positioned approximately 115 millimetres further to the front than in the long-wheelbase version of the BMW 7 Series running exclusively on gasoline, but is still about 25 millimetres further to the rear than in the standard-wheelbase saloon. As a result, legroom is as generous as one would expect in a car of this class also in BMW Hydrogen 7.
This particular touch of comfort, class and style is also underlined by the car’s unusually wide range of standard features: Over and above the high level of equipment featured from the start in the BMW 760i, BMW Hydrogen 7 comes with climate comfort composite glazing, BMW’s high-end automatic air conditioning, auxiliary heating, electric seat heating for the driver, front passenger and rear seats, lumbar supports, electric seat adjustment with memory function on the front seats, ISOFIX child seat fastenings, Park Distance Control, a rain sensor, exterior and interior mirrors with automatic anti-dazzle, Soft Close Automatic for the doors, and a headlight assistant.
A particular sign of distinction is the imprint “BMW Hydrogen Power” on the sunblinds on the rear side windows, with the same message being proudly presented in the illuminated door entry strips.
BMW’s navigation system Professional, the HiFi system Professional complete with a CD changer, as well as a rear monitor with a DVD changer and TV function with DVB-T reception and a separate telephone at the rear all ensure maximum grand touring comfort.
Yet a further highlight of BMW Hydrogen 7 is the BMW Assist telematics service and the Teleservice preparation kit. Then of course there are further highly convenient features such as Comfort Access, a heated steering wheel, Active Seats at the front, Comfort Seats at the front, active seat ventilation at the front, BMW Night Vision, Adaptive Headlights as well as voice recognition for controlling the navigation system, telephone and audio system also in BMW Hydrogen 7. And last but certainly not least, BMW Online also provides access to special BMW Hydrogen information pages.
Progress without compromises
BMW Hydrogen 7 clearly contradicts the assumption that changing over to an alternative form of energy means missing out on superior driving dynamics and motoring comfort.
On the contrary: Neither in its exterior looks nor in its driving behaviour does BMW Hydrogen 7 resemble any of the cars presented so far in the general context of innovative drive technologies. Accordingly, this departure from fossil fuel does not in any way mean giving up the dynamics and performance so typical of a BMW. Rather, mobility of tomorrow and driving pleasure of today are by all means compatible, with the drive concept of BMW Hydrogen 7 being directly transferable also to future models. So driving a car of this calibre will be just as thrilling in future as it is today, but at the same time cleaner than ever before.
Experiencing the future in BMW Hydrogen 7
Driving a BMW Hydrogen 7 means more than “just” experiencing the dynamic performance and supreme comfort of an exceptional luxury performance saloon. For the discerning individual driving the first hydrogen car in the world developed for everyday use will at the same time be enjoying a truly exceptional pioneering experience. Indeed, such a first-hand experience of a breakthrough into a new age of individual mobility also means contributing to this development through one’s own expertise and probing mind. Precisely this is why every user of a BMW Hydrogen 7 is in exceptionally close touch with the engineers of the BMW Group involved in developing the car and its technology, allowing direct answers to all questions possibly arising in the everyday use of such a brand-new technology. And of course this also means that BMW Group specialists receive ongoing and direct feedback on the everyday experience of “regular” motorists with the world’s first hydrogen car driven under regular conditions on the road.
There can be no doubt that the launch of BMW Hydrogen 7 also marks the beginning of an important test period. For despite the most intense testing, certain knowledge and findings can still only be obtained under practical driving conditions, particularly the “usability” of specific components in everyday motoring. After all, BMW Hydrogen 7 differs in numerous details and functions from a BMW 7 Series with a conventional gasoline engine.
Launching BMW Hydrogen 7, the BMW Group seeks not only a close dialogue, but also close cooperation with its customers: To establish hydrogen as a sustained alternative to fossil energy for individual mobility, ongoing development of technological potentials must be conducted in parallel to a close, direct and intense focus on the demands and interests of the car’s users.
Ultimately, therefore, this breakthrough into a new era of mobility is a challenge to all groups involved in this process. And the signal the BMW Group is sending out through the introduction of BMW Hydrogen 7 is directed not only to the network partners involved in politics, science and the energy industry, but also to an open-minded clientele highly sensitive to trendsetting innovations in the world of mobility.
