The hydrogen era has begun

On the 11th of May in Berlin BMW presented the world's first series
production hydrogen car, the BMW 750hL. The luxurious saloons will be
used as shuttles for the entire duration of the EXPO 2000 and will
convince their passengers that they meet the very highest requirements
regarding comfort, dynamics and utility value at market-appropriate
costs. "And we will be the first automobile manufacturer in the
world to offer series production hydrogen cars," says Dr. Burkhard
Göschel, Development Director of the BMW Group. Thousands of
hydrogen cars, adequate infrastructure in 2010 Dr. Burkhard
Göschel: "Our vision is to have a hydrogen fuel station
available in the vicinity of the branches of the BMW Group in Germany
by the 11th of May 2005." BMW offers international energy
companies close cooperation for the development of a hydrogen fuel
station network: "our aim is to have a sufficient network of
hydrogen fuel stations all over Europe by the year 2010," says the
development chief. By then BMW has planned to have sold several
thousand hydrogen cars. The prices for the cars and for the fuel are to
be similar to those of conventional cars and fuels. 750hL: a hydrogen
saloon for everyday use The hydrogen technology used in the 12-cylinder
saloons has already been advanced so far as to permit realistic
planning for large series production. In this way BMW has extended its
leading position in the development of the CleanEnergy car. CleanEnergy
is the generic term for the ecologically ideal, closed energy cycle
based on water. Running on hydrogen, the 12-cylinder engine delivers
150 kW/204 bhp, it accelerates from standstill to 100 km/h in 9.6
seconds and achieves a top speed of 226 km/h. Fitted with the 140 litre
Cryo fuel tank, the fully equipped 7 Series has an additional range of
350 kilometres. The car features conventional fuel supply, too, since
hydrogen supply is not safeguarded yet. After the EXPO in Hanover is
over, the saloons will drive back to Munich on their own power using
conventional fuel. The engine itself differs mainly only with regard to
the intake duct with additional injection valves for the hydrogen. The
production of the 7 Series BMW was incorporated as far as possible into
the normal production process. The 12-cylinder engines were integrated
into production in the Dingolfing plant and assembled together with the
conventional spark-ignition and diesel engines. The hydrogen is stored
cryogenically - i.e. in supperchilled and liquid form - at a
temperature of around minus 250 degrees Celsius in a double-walled steel
tank behind the rear seat-backs. Two safety valves ensure controlled
ventilation in the case of excess pressure. They are also part of the
comprehensive safety concept which proved its reliability in numerous
crash tests. Even in the case of a massive rear-end collision in which
the tank would be affected in its protected area, the steel cylinder
with its two times two millimetre thick walls did not leak. Even
greater deformations which would leave only little room for occupant
survival might cause a leak in the tank which, however, cannot explode.
For an explosion to occur, hydrogen and air would have to mix but due
to the higher inner pressure of the hydrogen, air cannot enter the
tank. The first series-produced cars with fuel cell A number of the
BMW hydrogen saloons are the first series-produced cars to feature a
fuel cell for supplying on-board electricity. This
"electrochemical" battery takes on the function it does best:
the production of electricity with a very high degree of efficiency of
up to 50 percent. The compact fuel cell battery in the 7 Series with
hydrogen drive is only as big as a conventional lead storage battery.
However the five kilowatt unit outperforms the lead version by far. In
this way the so-called fuel cell APU (Auxiliary Power Unit) not only
takes on the supply of all conventional electric consumers, but also
allows for new functions. The trailblazing 7 Series model features
stationary air conditioning which cools the interior even if the engine
is turned off. Pioneering service concept: permanent checking function
via radiotelematics Like the Formula 1 racing cars, all 750hL cars are
radio-linked to the service computer in the development workshop in
Munich - 24 hours around the clock. This way it is possible to monitor
all systems permanently and to react instantly to the slightest
deviation. Not only are all hydrogen data transmitted and checked, but
all data processed by the standard bus system in the 7 Series, too.
"The workshop knows that something is wrong before the driver
does", explains Klaus Pehr, the BMW engineer responsible for
hydrogen cars. The insights gained in this way are incorporated into
the on-going improvement of the hydrogen fleet. By means of a rotating
deployment plan for the environment-friendly 7 Series, it is
safeguarded that all cars are brought up-to-date as quickly as
possible. After the world exhibition is over on October 31st the level
which has been achieved will be presented. The telematic checking
system has already proved its usefulness in the development stage.
Thanks to this system, the car check conducted every evening in Hanover
is reduced to a short operation in the branch where mainly only the
sensors have to be calibrated. There the 750hLs are also refuelled with
hydrogen using a so-called mobile "Cryo-Can". Hydrogen
engines: lean-burning mixtures prevent emissions Since the end of the
seventies, BMW has been dealing with the topic of hydrogen drive. In
the meantime the fifth generation of hydrogen cars is on the road,
advanced on the basis of the BMW 7 Series of the period. Today, too,
the basic engine is a series-production engine but the hydrogen drive
calls for some changes ranging from the fuel system to the mixture
formation process. An electronic mixture formation system has been
developed which precisely matches hydrogen injection and charge
changes. Combustion generally takes place with an excess of air. The
additional air in the combustion chamber absorbs heat and reduces the
flame temperature to below the critical level above which the mixture
could ignite by itself. At the same time the low combustion temperature
also prevents the production of nitric oxides (NOx), which have to be
detoxified by catalytic converters in petrol-engine cars. So even
without additional exhaust emissions treatment, the BMW hydrogen
engines operate almost entirely without emissions. This
environment-friendly engine layout leads to a reduction in specific
output. However, this can be compensated for by e.g. adapting the cubic
capacity. Engines designed only for hydrogen operation do not have to
make this compromise and are at least on a level with spark-ignition or
diesel engines as far as specific output is concerned. Refuelling in
only three minutes A further prerequisite for the introduction of
hydrogen as fuel is a filling system which must be no more complicated
than filling a car today. The low temperature of minus 250 degrees
Celsius requires a special type of technology. In cooperation with its
project partners, BMW has developed a fuelling system which can be used
to fill vehicles with hydrogen as quickly, loss-free and safely as with
conventional fuels. The latest version of this technology is currently
being used by the world's first public robot fuel station for liquid
hydrogen at the Munich airport. The fully automatic hydrogen fuelling
operation takes less than three minutes and is a simple process for the
layman. BMW promotes solar electricity for generating hydrogen
Hydrogen can only be a sensible alternative to conventional fuels if the
electricity needed for generating it from water can be produced with
renewable energy sources. This can for example be achieved by means of
solar cells which produce electricity directly. Or solar powerplants
with groove-shaped parabolic mirrors, which operate on the principle of
the steam turbine, are a promising alternative. Such a system is
already in operation in the Californian Mojave desert. In order to test
such scenarios BMW already joined the solar hydrogen project in
Neunburg vorm Wald at an early stage, where the photovoltaic generation
of hydrogen and its use for different purposes was studied. The aim is
to produce sufficient amounts of hydrogen economically using solar
energy. BMW supports practice-oriented hydrogen initiatives BMW
supports initiatives at all levels that help to create the necessary
conditions for the introduction of hydrogen powered cars. The
"European Integrated Hydrogen Project" for example aims at
harmonising hydrogen relevant regulations internationally. The goal is
to provide lawmakers with a sound basis for making decisions. Concepts
for standardising infrastructure and vehicle components are being
developed. BMW has joined together with nine partners from the world of
business and research for this purpose. Work is running on two tracks:
a top-down process will analyse already existing hydrogen relevant laws
in Europe. On this basis suggestions for Europe-wide standardisation
are to be worked out. The bottom-up analysis examines existing vehicles
and infrastructures to identify safety relevant aspects. They will then
be used as a basis for discussions with the authorities. With this
project BMW aims to bring about general licensing for hydrogen powered
vehicles. HYROFORUM 2000 to strengthen international alliance for
hydrogen In addition BMW has been very active in bringing about the
international hydrogen conference HYFORUM 2000 which will take place in
Munich in September 2000. It is purposefully aimed at high-ranking
decision-makers from industry, finance, insurance and politics. Its
goal is to bring together important partners and to direct their
attention to the topic of hydrogen as an energy source. Wide-ranging
cooperation is now called for in order to pave the way for hydrogen to
move from research to application. To achieve this we do not only need
technical decisions, but also political decisions. From the HYFORUM 2000
we expect answers to the energy question in the 21st century. As an
international forum HYFORUM 2000 will send out signals to the entire world.