The large hydrogen station at Grjótháls (see maps and links for the orientation, but GPS is 64°07'26 N;21°48'08 W) stands on the same lot as the Shell branded gasoline station at Vesturlandsvegur. The station produces a maximum of 60Nm3 /h or 60 cubic metres every hour during operation when measured at the standard temperature 0°C.
On the figure you see a drawing of the whole faciltiy from a birds eye view and a picture of visitors at the gate of the station. Visitors are not allowed inside the gates during times of operation. But the electrolyser is in the container to the left, as seen from the gate, the compressor at the far end in a smaller container and the steel storage cylinders to the right behind the yellow warnig sign that states, please leave the gate free for access.
The hydrogen station makes hydrogen from water with electrolysis (see further below and our teaching CD!). The water comes from the city's piping system, it's the same water as the citizens have in their cold water taps. It was scaled to be able to fill 3 hydrogen buses daily so that they could keep up their 150 - 200 km schedule on each filling, leaving also some pressure buffer in the furel tanks. Another way of describing the scale is that it has enough capacity to produce hydrogen to satisfy up to 600 personal cast in general operation. During the bus tests between 20 and 25 kg of hydrogen were filled on the buses before they went to service. The cars that are now driven in Reykjavik take about 2-4kg each time they are refuelled. The figures show two types of vehicles at the station. The cooling unit rises above the station walls, but as can be seen it is rather small if compared to cooling towers in power plants. Notice that there are no emissions visible because the only gas type that escapes the process is oxygen the gas type that we take up through our lungs when breating.
The hydrogen station is composed of several modules that were all deliverd from www.Electrolysers.com (formerly Norsk Hydro and HydroStatoil). The electrolyser looks like a container. Inside is a gadget that resembles a heap of steel-pancakes stacked on its side. The electrolyser is a complex structure built to lead electricity through water and keep the oxygen and hydrogen that form separated. The process water is filtered and deionised before the electrolysis. In simpe terms the electrolytic process is as follows: The electricity passes through the water which is mixed with KOH and splits up the water molecules into two gas types: hydrogen (H2) and oxygen (O2). The Oxygen is not collected but vented to the atmosphere insead. The hydrogen is collected into pipes wich lead to a cooling tower, compressor and from there to storage cylinders. The KOH, is added to the water to speed up the separation by raising the conductivity of the solution but does not enter as raw material in this electro-chemical reaction. Oxygen and hydrogen have opposite affinity and different chemical properties. If they get in contact with each other, water reforms quickly. This means that the material used in the module is carefully selected to withstand corrosion and abraisive chemicals and it needs to be extremely pure and tight. The figures show the electrolyser stacks with lye tanks. The drawing is from the CD ROM and shows the reaction.
When the station is shut down it needs to be flushed with inert gas to get the hydrogen and oxygen out of the electrolytic modules. Nitrogen (N2) is used for this purpose and is kept in a few green pressurized cylinders at the station. The formed hydrogen is dried and cleaned of all water molecuels which gives a grade of hydrogen up to 99.9999% purity. This is essential if it is to be used with PEM fuel cells that are commonly used in hydrogen vehicles.
On the station the compressor lies to the right of the electrolyser. It brings the ydrogen under pressure of about 450 bars ( * 14.5 psi) and leads it into the storage cylinders. At the station the cylinders are made of steel and are connected to faciltate the pressure monitoring. The figures below show a part of cylinder that will form the bottom. Note how thick the walls are. The other figure shows a hydrogen container of the type that is usually in vehicles. These are wrapped with carbon fibres to make them strong and withstanding high pressure, but still keeping them relatively light as well.
The system allows drivers to fill hydrogen onto their cars but they will need a key to unlock the filling and a card to operate the card reader. The dispensing systems works in that way that the hydrogen moves first from the cylinder that has the lowest pressure until the pressure in the vehicle is about 20bars lower 
than the pressure in the storage cylinder. Then the hydrogen dispenser shifts to a cylinder that has higher pressure. If that is not enough the third step is available to top the filling with pressure from the highest pressure storage. To monitor this kind of filling and slow it down so that the pressure does not form to quickly, two pipes are lead from the hydrogen station and fastened to the fuel tank of the car with a click. One of the pipes carries the hydrogen stream but the other is a ventialting tube. They are connected to a sensitive monitor that measures the pressure on both sides and manages the filling to secure safe transfer. The monitor slows down the filling because the nozzle and tank get heated from the changing pressure. Therefore the pressure rises even more. The stream of hydrogen is measured and converted to kilograms. Each kilogram is sold for 1390Ikr. The hydrogen station is unmanned but instructions display how to fill onto the vehicle. If mistakes are made during filling the station shuts down automatically. It is safest to follow the instructions maticulously, but these are written in English and in Icelandic above the nozzle where it is locked to the dispenser.
The card reader asks for the reading at the ODO meter before the refuelling begins. This data is collected to monitor the vehicle use and to find the efficiency. It is therefore very important for Icelandic New Energy that car users fill out this figure concicely. The information on the amount of filling is collected by the system and the fuel bill will be sent to the car owner. On the outer panels of the station the process is explained in Icelandic and English. The spirit of the station was designed by Conran architechts in London.