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Hydrogen at home

The most important stationary application of fuel cells and hydrogen is the co-generation of electric power and heat in a fuel cell heating and power station. The advantage of making use of both products - electric power and heat - is the very high overall system efficiency thus making the best possible use of the primary energy sources

Such cogenerat[...]
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Hydrogen at home

The most important stationary application of fuel cells and hydrogen is the co-generation of electric power and heat in a fuel cell heating and power station. The advantage of making use of both products - electric power and heat - is the very high overall system efficiency thus making the best possible use of the primary energy sources

Such cogeneration fuel cell power stations can be realised even in very small construction sizes. Most common will be systems having the size of regular residential heating systems or of gas heating boilers. When these systems were produced in large numbers they would be only slightly more expensive than conventional heating boilers but in addition they are "incidentally" generating electric power!

One can imagine how our energy system would change if millions of such plants were installed directly in residential buildings. The generation of electric power would become decentralised and we would use the primary energy sources more efficiently

Hydrogen in your hands

A great variety of possible applications for fuel cells and hydrogen can be found in the energy supply of portable devices: mobile phones, laptops, walkmen, camcorders and many other things could be powered by hydrogen and by fuel cells in the size of batteries.
In this exposition you can have a look at a computer powered by a fuel cell. Its operation time far exceeds the operation time of computers powered by conventional accumulators. And when the hydrogen draws to an end one simply inserts a new cartridge. The empty cartridges can be refilled.

Fuel cells which are even smaller, so called micro fuel cells, could be integrated in mobile phones. Prototypes with an operation time of fifty hours have already been presente

Is hydrogen dangerous?

Hydrogen is highly inflammable, that means it easily reacts with oxygen and when it burns water is produced. Exactly this characteristic makes it suitable as a fuel.

Hydrogen has no greater danger potential than oil, natural gas or uranium. With regard to its physical and chemical specifications hydrogen is not particularly dangerous. Therefore, e.g. in Germany, the safety precautions and regulations for hydrogen do not differ from those for every other burnable gas.

In car accidents or air crashes liquid fuels often lead to fire slicks and in consequence frequently result in fatal injuries. In contrast to this hydrogen escapes upwards into the air very fast as proved by the accident of the airship "Hindenburg" in 1937. On the other hand one has to consider that there is an increased explosion hazard when hydrogen is set free in closed rooms, e.g. in garages or tunnels. In closed rooms good ventilation and perhaps additional safety precautions must be provided.

The chemical industry has been using hydrogen for hundred years. The experiences concerning safety are positive.
Hydrogen and fuel cells - a perfect combination

In this chapter we learn the basic facts of fuel cells. What for we need fuel cells, how they work and what is already reality.
Fuel cells gives us a very efficient way to produce electric power and heat. In the whole circle of renewable energies they are the final element. The sun provides energy, solar cells or wind power catch it for us, hydrogen is the storage and the medium to transport the energy and the fuel cells generate the energy whenever and whereever it is needed.

If we get into our car, if we need heat and electricity at home or if we just listen music on our walkmen. The energy could be provided by a fuel cell.

Basic construction

Fuel cells have a very simple structure. The cell itself consists of three layers, one above the other:

The first layer is the anode, the second an electrolyte and the third layer is the cathode.

Anode and cathode serve as catalyst. The layer in the middle consists of a carrier structure which absorbs the electrolyte. In different types of fuel cells different substances are used as electrolyte. Some electrolytes are liquid and some are solid with a membrane structure.

Because one cell generates only low voltage several cells get stacked according to the requested voltage. This arrangement is called "stack".

What exactly does a fuel cell?

The fuel cell reverses the process of electrolysis which is known from school. In the process of electrolysis by applying electric power water is decomposed into the gaseous components oxygen and hydrogen.

The fuel cell takes exactly these two substances and converts them to water again. In theory the same amount of energy which has been used for the electrolysis is set free by this conversion. In practice insignificant losses are caused by different physical-chemical processes.

So to say electric power is stored in hydrogen. Therefore we have a gas at our disposal in which electric power can be stored and this gas is hydrogen. In fuel cells we get back the electric power stored in the hydrogen. Most fuel cells are operating with air, so there is no need to store oxygen.
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