The windmill enthusiasts have been talking about America, the Saudi of wind power. Install windmills in the breezy midwest and transmit the juice to the coasts. That's quite a haul. The old rule of thumb was electric power transmission worked for 400 miles, losses become excessive for anything more. From the midwest to the coasts is a helova lot more than 400 miles.
Question, has the state of the art improved enough to ignore the 400 mile rule of thumb?
Losses in wire are equal to current squared times resistance of the line. Power transmitted is volts times amps, and so power is transmitted at the highest possible voltage, to reduce the current. Since the losses are caused by current, the lower current means lower losses.
Wire is aluminum, cause it is much lighter weight and lower cost than copper. Some fiddling with Excel gives the resistance of 400 miles of American Wire Gauge 0000 aluminum wire (0.43 inch diameter), the largest size in the wire table, as 170 ohms.
Consider transmitting 1000 megawatts (output of just ONE nuclear plant) over 400 miles. Use the highest voltage you dare, 750000 volts. That requires a current of 1333 amps.
Not good. Of the 1000 megawatts put into the line, fully 300 megawatts, 30% is lost as heat. That's gonna run up the cost of power. And we have only gone 400 miles.
Use thicker wire you say? Lets try that. Double the wire diameter, which increases the cross section, (and reduces the resistance) by four times. That helps some. At 400 miles the loss drops to 7.5% (tolerable) but it's still 30% at 1600 miles, the distance from Iowa to New England.
So, before signing on to a glorious green future based on mid west windmills, the T. Boone Pickens solution, better get some quotations on transmission lines, and line losses.
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