Week of February 15, 2009

Of late I have been researching new energy technologies other than alternative fuel production processes, and in particular mass electrical storage. Recently, I came upon a most interesting concept relating to the latter, though one whose feasibility may be doubtful.

Mass electrical storage is the most problematic aspect of commercial electrical generation and distribution. It is a truism to say that you can't store electricity—a truism that isn't precisely accurate, by the way—but it is certainly difficult to store electricity in bulk, and the means for doing so generally involve transducing electrical energy into some other form of energy, whether it be electro-chemical, hydraulic, or electromagnetic. Only two devices may be said to store electricity in the strictest sense—superconducting rings, which aren't very practical, and ultra-capacitors, which aren't very practical either.

The concept I'm going to describe involves a greatly improved sort of capacitor, one that doesn't exist at present but which may be perfected soon, but I'll leave the discussion of the underlying technology to another entry. I'm more interested in the way the technology might be deployed.

The scheme I discovered is specifically intended to serve wind farms, which are currently proliferating on the Great Plains. Now anyone who follows the wind energy industry understands that one of its biggest problems, particularly in the excellent wind regimes of West Texas and Oklahoma, is that existing transmission capacity is inadequate and the inadequacies would cost billions to redress.

So here's the proposed fix:

Most wind farms our located in areas served by railheads or at least by public roads. If one had a sufficiently energy dense storage medium, one could simply tap the output of the wind farm or other renewable source and then move the storage medium to where grid access were available.

I haven't really examined the economics for doing this, though I do know that transport by rail is far cheaper and more energy efficient than transport by over-the-road trucks. Provided the distance were not excessive, say a few score miles or so, the operational cost shouldn't be that high. And, if one were to use some of the stored electrical energy to run an electrical motor, the cost savings would be far greater. Modern electrical motors are over 90% efficient, as are capacitor based storage systems. Using internal combustion in this instance would make no sense.

If the electrical storage vehicle were stream-lined, the efficiency would be far greater. And the bigger the vehicle the higher the efficiency because internal volume increases much more rapidly than surface area, and surface areas create aerodynamic drag.

Anyway, it's an interesting notion.