Unlike fossil fuels such as petrol or diesel, hydrogen is not a source of energy in its own right. It is merely a means for storing electricity generated in a power station and delivering it to the motor driving the wheels of an electric vehicle-in much the same way as a battery works. And as free hydrogen does not occur in useful quantities in nature, it has to be made by using electricity to crack water into its constituent elements.
In California, despite the many solar installations and wind farms, the electricity coming out of the plug is neither green nor clean, being derived predominantly (ie, 62%) from fossil fuel. During cheap-rate periods at night-when electric vehicles tend to be recharged and electrolysis plants are running flat out-most of California's electricity is imported from coal-fired power stations out of state. Thus, like electric vehicles, hydrogen cars contribute their share of greenhouse gases as well.
http://www.economist.com/blogs/babbage/2012/10/nitrogen-cycle
Micro nuclear powered hydrolysis stations, anyone?
A growing body of opinion seems to think liquid air is the answer (or, more specifically, the nitrogen component that makes up 78% of air). It is not exactly a new idea. Air was first liquefied in 1883, using essentially the same process as today-ie, compressing it to 200 atmospheres, cooling it to -190ºC, and then letting it suddenly expand and condense. The process turns 1,000 litres of transparent gas into 1.4 litres of light blue liquid.
As long as its storage container is well insulated, liquid air can be kept at atmospheric pressure for long periods. But on exposure to room temperature, it will instantly boil and revert back to its gaseous state. In the process, it expands 700-fold-providing the wherewithal to operate a piston engine or a turbine.
Liquid nitrogen does an even better job. Being considerably denser than liquid air, it can store more energy per unit volume, allowing cars to travel further on a tankful of the stuff. Weight for weight, liquid nitrogen packs much the same energy as the lithium-ion batteries used in laptops, mobile phones and electric cars. In terms of performance and range, then, a nitrogen vehicle is similar to an electric vehicle rather than a conventional one.
In California, despite the many solar installations and wind farms, the electricity coming out of the plug is neither green nor clean, being derived predominantly (ie, 62%) from fossil fuel. During cheap-rate periods at night-when electric vehicles tend to be recharged and electrolysis plants are running flat out-most of California's electricity is imported from coal-fired power stations out of state. Thus, like electric vehicles, hydrogen cars contribute their share of greenhouse gases as well.
http://www.economist.com/blogs/babbage/2012/10/nitrogen-cycle
Micro nuclear powered hydrolysis stations, anyone?
A growing body of opinion seems to think liquid air is the answer (or, more specifically, the nitrogen component that makes up 78% of air). It is not exactly a new idea. Air was first liquefied in 1883, using essentially the same process as today-ie, compressing it to 200 atmospheres, cooling it to -190ºC, and then letting it suddenly expand and condense. The process turns 1,000 litres of transparent gas into 1.4 litres of light blue liquid.
As long as its storage container is well insulated, liquid air can be kept at atmospheric pressure for long periods. But on exposure to room temperature, it will instantly boil and revert back to its gaseous state. In the process, it expands 700-fold-providing the wherewithal to operate a piston engine or a turbine.
Liquid nitrogen does an even better job. Being considerably denser than liquid air, it can store more energy per unit volume, allowing cars to travel further on a tankful of the stuff. Weight for weight, liquid nitrogen packs much the same energy as the lithium-ion batteries used in laptops, mobile phones and electric cars. In terms of performance and range, then, a nitrogen vehicle is similar to an electric vehicle rather than a conventional one.
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