The BMW Clean Energy system involves liquid hydrogen produced from water using solar power. Hydrogen as a motor fuel is the answer to many environmental problems since there are no harmful emissions, no depleting of resources, and no danger to the atmosphere.

Since the 70's, BMW has been researching the future of mobility. The fruit of the research is the new BMW 750hL hydrogen powered vehicle. 

The heart of the 750hL is a hybrid, 12-cylinder combustion engine with two independent electronically controlled fuel induction systems. These systems allow the 750hL to run on either gasoline (petrol) or hydrogen. 

The 750hL has a hybrid 12-cylinder combustion engine capable of running on either gasoline or hydrogen. The 5.4-liter engine has two independent, electronically controlled fuel induction systems. The hydrogen engine offers excellent torque and acceleration, while the specially insulated 140-liter tank for the liquid hydrogen provides a range of 400 kilometers. 

The Process:

Electricity generated from solar power is used to split water into hydrogen and oxygen. Oxygen is released into the atmosphere, while hydrogen is liquefied and stored at a very low temperature (-253 °C). 

During internal combustion, the hydrogen combines with oxygen. The resulting energy powers the vehicle, while the hydrogen is returned to the environment as water. Harmful emissions are virtually eliminated.

By cooling hydrogen to -253 degrees Celsius, hydrogen is shrunk to a thousandth of its original volume. 70 layers of aluminum and fiberglass sheets between the exterior and interior vehicle walls insure that the liquid hydrogen remains at extremely low temperatures.

The car gets electricity from a newly developed fuel cell battery that converts hydrogen into electric current, and because it has several cells in series, it supplies enough power to keep the climate control running even when stationary.

Working with Shell Oil Company, BMW has developed a technology for dispensing hydrogen from a filling station's pumps into a car's fuel tanks. The world's first fully automatic hydrogen filling station was opened in May 1999 at the Munich Airport.

Other BMW Partners:

• Parabolic-trough and solar-chimney installations transform heat from the sun's rays into electricity; their simplicity, longevity and ease of maintenance make them particularly cost-effective. Solar Millennium AG and its partners set up such power stations at appropriate locations in the Earth's sunniest places.

• Hydrogen is normally a gas and takes up a great deal of space if it's stored as such. By cooling it to -253 degrees Celsius, Linde is able shrink hydrogen to a thousandth of its original volume, thus raising the energy content. Linde has also developed a special fuel tank which keeps the hydrogen at this temperature through high-tech insulation.

• Together with Messer AG, a contact-free method of fixing the inner tank in place was developed using high-temperature superconductor technology. This highly innovative technology helps keep the hydrogen supercooled for longer.

• In collaboration with IFC, a fuel cell was developed that supplies enough power for all the 750hL's electrical needs. Its high efficiency even leaves it with sufficient surplus power to keep the air- conditioning running when stationary.