It is definitely cheaper to run air in plastic pipe rather than electricity in copper wire. Somewhere around here are the calculations and/or figures to show the pressure loss for (say) 1/2", 3/4", and 1" pipe over distance.

I will be running about 600 feet of air (hopefully) later this year and plan on using 1" black plastic water pipe. It's about 2x the price of 1/2" and 1/3 more than 3/4", but the line loss is much less. And I may be daisy-chaining air through this pipe even further in the (distant) future.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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