Fuel Cells convert chemically bound energy to electricity, almost like a battery but with the important difference that the electricity production from a fuel cell does not end as long as fuel is fed. Fuel in the form of hydrogen is fed to the anode of the fuel cell and oxygen is fed to the cathode. The hydrogen can be received by reforming, for example natural gas, biogas, methanol, ethanol or by electrolysis of water. The oxygen is received from air. Chemical reactions generate the end products to be electricity, heat and water. The fuel cell itself does not contain any moving parts, it is a very silent technology, without pollutants and with little maintenance.
A fuel cell can be used in different ways depending on where it is installed in the world. In the US, where the activity in this area is large, it is primarily seen as an electricity generator due to the high valuation of the electricity prices that are applied. The electricity prices reach their peak on summer when the cooling demand is largest.
In Sweden the fuel cell will more have the role of a combined power and heat plant, as the electricity in general is most expensive when it is coldest in Sweden. Therefore the fuel cell is, at the moment, a potential opportunity for stand alone houses, that by different reasons can not be connected to a district heating system due to economical reasons, for example small houses, but also office buildings that are located outside of densely populated areas.
History
In 1839 Sir William Robert Grove discovered the ability of hydrogen to transport energy and in connection with this discovery the fuel cell was invented. However, not until in the 1960´s under the space technology development, the technology took off. At that time a large amount of money was spent on the fuel cell, as it in a space capsule can produce both electricity and drinkable water. Today there are a lot of projects whose purpose is to develop and find new application areas for the fuel cell. There are, for example, over 250 fuel cell power plants on 200 kW in continuous operation.
Test series with buses that are powered with fuel cells have been done and are also under investigation. All the major car manufacturers are right now developing fuel cell powered cars. Extensive tests are also made to replace batteries with fuel cells in portable electronics.
Supplier
H Power,Canada, has through NAPS Systems, Finland, delivered a fuel cell system of the model RCU4500 (RCU = Residential Cogeneration Unit) to “GlashusEtt”. On March 25, 2003, Plug Power, USA, and H Power merged to one company.
The fuel cell uses a polymer membrane as a solid electrolyte, which has led to that the technology is abbreviated PEM = Proton Exchange Membrane. The fuel cell system can be fuelled with biogas, which is reformed to hydrogen or with hydrogen produced by the electrolyzer in the building. The biogas is received from the nearby water sewage treatment plant.
The fuel cell can produce about 4 kW electricity and about 6,5 kW heat. The size of the fuel cell system is 160 cm (L) x 114 cm (D) x 142 cm (H) and the weight is 1360 kg