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In 1800, British scientists William Nicholson and Anthony Carlisle had described the process of using electricity to decompose water into hydrogen and oxygen. William Robert Grove, however took this idea one step further or, more accurately, one step in reverse in 1838. Grove discovered that by arranging two platinum electrodes with one end of each immersed in a container of sulfuric acid and the other ends separately sealed in containers of oxygen and hydrogen, a constant current would flow between the electrodes. The sealed containers held water as well as the gases, and he noted that the water level rose in both tubes as the current flowed. By combining several sets of these electrodes in a series curcuit, he created what he called a "gas battery"- the first fuel cell. This experiement was confirmed later by Christian Friedrich Schoenbein who observed that during electrolysis of water, when switching off the power, a reverse current started to flow.

The real development of the fuel cell started in 1960 when NASA was looking for a device to power its Gemini and Apollo spacecrafts providing enough electricity at a lighter weight than standard batteries. The modern fuel cell development started in the General Electric labs. Today, approximately 80 companies and public laboratories around the world are working on improving the fuel cells efficiency; more than 60 of them are located in North America.

Inside the fuel cell, no burning of fuel takes place, the electricity is produced through a chemical reaction. In the hydrogen – oxygen PEM fuel cell (Polymer Electrolyte Membrane) for instance, the transformation of hydrogen into electrical power generates only pure water and small quantity of heat as residual products. The operation of a fuel cell does not require any moving part, it is therefore reliable and efficient. The chemical reaction takes place between two electrodes (platinum) and a membrane (electrolyte) between the two electrodes.

Apart from the hydrogen ( PEM) fuel cell, several additional types of fuel cell have been developed, using various type of fuels. Ethanol, methanol (DFMC), phosphoric acid (PAFC), solide oxyde (SOFC), molten carbonate (MCFC), or the alkaline type (AFC). Actual fuel cells exist in a range of power starting at a few watts to hundreds of kilowatts per unit.

The hydrogen society.

At the present, human society find its source of energy in oil, natural gas, cowl, nuclear and electricity coming from various sources such as hydraulic power, (dams), nuclear, etc. One of these sources, oil, will reach its production peak in the years or decades to come and will then decline. Fossil fuels also have the inconvenient to generate CO2 when they are consumed, generating the “green-house” effect and a subsequent global warming of the earth climate. In a way to reduce the impact of the above problems, humanity is looking fossil fuel savings, and aims at replacing them with renewable energy sources. Electricity is mostly the carrying agent for the renewable energies produced by wind turbines, solar photovoltaïc panels, hydraulic power plants. The main drawback of electricity is that it is impossible to stock in huge quanty. Its transport is also generating important losses of energy. Combining renewable energies with hydrogen appears to be the most promising solution.

Hydro-electric power plant USA

Renewable, inexhaustible energy ? :

The sun brings every day 1.7 x 10 power 17 watts of energy that reach the top of the earth atmosphere. More than half of this huge amount of energy reaches the ground or the seas. This represents approximately 10'000 times le total power comsumed by humankind in 2007 ! Capturing this energy during 10 seconds each day or one hour per year could satisfy the entire supply of energy of human kind. This quantity of energy will be produced approximately 12 hours per day on much smaller surfaces compared to the complete surface of the earth. One can then refer to “inexhaustible energy source”.

Off-shore wind farm (Danemark)

How will this solar energy be captured and stored ? In this field, meaningful steps have been performed towards the working solutions.

Capture of solar energy can be performed at “photovoltaic solar farms” in the deserts, in the mountains on the sea. Very high power units will produce electricity that will then be converted into hydrogen to be stored in huge “reservoirs” of different kinds, or will be channeled via pipelines towards the consumption centers, factories or cities. Other photovoltaic installations will serve private houses of office buildings. A private house, equiped with 60 to 80 square meters of photovoltaic panels, an electrolyzer to produce the hydrogen, a storage tank, and fuelcell(s) will be entirely autonomous in energy, it will not require any connection to the “grid”.

 

D'autres installations de dimension plus modestes équiperont les immeubles et les maisons individuelles. Une maison individuelle équipée d'environ 60 – 80 m2 de panneaux photovoltaïques, d'une capacité de stockage d'hydrogène et d'une pile à combustible serait parfaitement autonome du point de vue énergétique sous nos latitudes. Une telle installation fournirait l'énergie suffisante pour le chauffage, l'eau chaude, l'alimentation électrique de tous les appareils du ménage, surer la climatisation en été. Le propriétaire bénéficierait d'un supplément d'hydrogène pour alimenter sa voiture en carburant renouvelable.

Solar photovoltaic powerplant

  • Other hydrogen plants will pull its energy from the sun with thermal panels or mirrors and steam turbine. Very large plants of this technology will be built in deserts, in mountain areas or on the sea. Such thermal powerplants already exist to produce non-stockable electricity. While switching electricity production to hydrogen will bring the benefit of storage and transport capability. Transformation of cowl, wood, into hydrogen may sound inefficient. However when centralized in large facilities, this solution brings the benefit of better controlling and capturing the resulting CO2.

    Additional sources of energy like geothermal, biomass, tide etc will also allow to produce huge quantity of renewable hydrogen which will then be channeled or transported towards the consumption centers.

Solar thermal power plant

Clean energy :

One of the most important benefits of hydrogen technology is that its consumption does not generate any waste. The only residue of hydrogen transformed into electricity inside a fuel cell is pure water and a little bit of heat.

Tidal power plant (France)

Hydrogen, the promise...

Hydrogen as a fuel allows production and storage clean, renewable, efficient, zero carbon energy; this has now been proven. Nowadays, lots of laboratories, private or public, all around the world work hard to achieve further improvements in the hydrogen technology. Fuel cells keep improving their efficiency, processes to produce hydrogen are being optimized, storage techniques allowing more energy to be kept in smaller volumes are being developed. The “world” is at work to extend the use of hydrogen as a pervasive fuel for the future.

Solar island photovoltaic or thermal

Today already, in the USA and in Germany transport facilities use hydrogen and fuel cells to power buses, cars, boats, trucks . In Hamburg thirty public transport buses carry thousand of people every day on such zero emission hydrogen vehicles. An Horizonfuelcell ltd ™ hydrogen bicycle has just been introduced on the market. Its reserve of hydrogen allows an autonomy of 300 Km. The hydrogen society is on its way, its development accelerates ands it demonstrates a strong potential, it permits us to look forward to the future with confidence...

Hydrogen energy related Links.

www.clean-air.org - www.drivingthefuture.org - hydrogen.dot.gov - www.h2euro.org - www1.eere.energy.gov/hydrogenandfuelcells/education

h2andyou.org/caseStudies/portable.asp - www.annso.freesurf.fr - www.hydrogen.energy.gov - www.afh2.org - www.h2euro.org