to the megawatt range by multiplying the available reactor units and by connecting the plant to heliostat fields (fields of sun-tracking mirrors) of a suitable size. Thermochemical production There are more than 352 thermochemical cycles which can be used for water splitting, around a dozen of these cycles such as the iron oxide cycle, cerium(IV) oxide-cerium(III) oxide cycle, zinc zinc-oxide cycle, sulfur-iodine cycle, copper-chlorine cycle and hybrid sulfur cycle, aluminum aluminum-oxide cycle, are under research and in testing phase to produce hydrogen and oxygen from water and heat without using electricity. These processes can be more efficient than high-temperature electrolysis, typical in the range from 35% - 49% LHV efficiency. Thermochemical production of hydrogen using chemical energy from coal or natural gas is generally not considered, because the direct chemical path is more efficient. None of the thermochemical hydrogen production processes have been demonstrated at production levels, although several have been demonstrated in laboratories. Microwaving plastics A 97% recovery of hydrogen has been achieved through microwaving plastics for a few seconds that have been ground and mixed with iron oxide and aluminium oxide. Hydrogen as a byproduct of other chemical processes The industrial production of chlorine and caustic soda by electrolysis generates a sizable amount of Hydrogen as a byproduct. In the port of Antwerp a 1MW demonstration fuel cell power plant is powered by such byproduct. This unit has been operational since late 2011. The excess hydrogen is often managed with a hydrogen pinch analysis. The world's first hydrogen electric plant, in Italy, had a capacity of 12MW, cost about 6 times more than conventional means, and was shut down in less than two years. Gas generated from coke ovens in steel production is similar to Syngas with 60% hydrogen by volume. The hydrogen can be extracted from the coke oven gas economically. Storage Although molecular hydrogen has very high energy density on a mass basis, partly because of its low molecular weight, as a gas at ambient conditions it has very low energy density by volume. If it is to be used as fuel stored on board the vehicle, pure hydrogen gas must be stored in an energy-dense form to provide sufficient driving range. Pressurized hydrogen gas Increasing gas pressure improves the energy density by volume making for smaller container tanks. The standard material for holding pressurised hydrogen in tube trailers is steel (there is no hydrogen embrittlement